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if (pos > 0) { while (pos > 0) { var t = e.childNodes(0); var n = document.createElement("PRE"); var s = t.splitText(pos); e.insertAdjacentElement("afterEnd", n); n.appendChild(s); e = n; pos = e.innerText.indexOf("\n"); } var count = (par.children.length); for (var i = 0; i < count; i++) { e = par.children(i); if (e.tagName == "PRE") { pos = e.innerText.indexOf(">"); if (pos != 0) { n = document.createElement("DIV"); e.insertAdjacentElement("afterEnd", n); n.innerText = e.innerText; e.removeNode(true); } } } if (par.children.tags("PRE").length > 0) { count = (par.childNodes.length); for (i = 0; i < count; i++) { e = par.children(i); if (e.tagName == "PRE") { e.id = ""; if (i < (count-1)) { var e2 = par.children(i + 1); if (e2.tagName == "PRE") { e.insertAdjacentText("beforeEnd", e2.innerText+"\n"); e2.removeNode(true); count = count-1; i = i-1; } } } } } } else { n = document.createElement("DIV"); par.appendChild(n); n.innerText = e.innerText; e.removeNode(true); } } --></SCRIPT> </HEAD> <BODY onload="position();" onresize="position();" oncontextmenu="return true"> <H1>rocks_east</H1> <H2>File Geodatabase Feature Class </H2> <TABLE cols="3" frame="void" rules="cols" width="315" height="28"> <COL WIDTH="105" /><COL WIDTH="105" /><COL WIDTH="105" /> <TR height="28" onmouseover="doHilite()" onmouseout="doHilite()" onclick="changeTab(this)"> <TD ID="DescTab" CLASS="tsel" TITLE="Click to see a description of the data">Description</TD> <TD ID="SpatialTab" CLASS="tun" TITLE="Click for details about the spatial data">Spatial</TD> <TD ID="AttribTab" CLASS="tun" TITLE="Click for details about the attribute data">Attributes</TD> </TR> </TABLE> <DIV ID="Group" CLASS="f"> <DIV ID="Description" CLASS="pv" STYLE="display:block"><BR /> <DIV CLASS="pn">Keywords</DIV> <DIV STYLE="margin-left:0.2in" CLASS="lt2"><SPAN CLASS="pn">Theme: </SPAN> geology</DIV> <BR /> <DIV CLASS="pn">Description</DIV> <DIV CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Abstract <DIV CLASS="pe2" STYLE="display:"> <SPAN CLASS="lt"><PRE ID="original">Clearwater National Forest Geology 2000 derived from Thematic Mapping Database Idaho Geological Survey University of Idaho Moscow, Idaho 83844-3014 This spatial data set covers the Nez Perce and Clearwater National Forests, Idaho, including the following 30 x 60 minute quadrangles: Kooskia Hamilton Missoula West Headquarters Geologic Mapping This database represents years of work by many individuals. Field geology involves many tasks including photo interpretation, field checking, field data collection, drill hole interpretation, and geologic interpretation. Geologic mapping is a highly subjective science. The geologic data presented here was compiled from existing, published and unpublished, geology to give continuous coverage over a large area. A compilation geologic map is pieced together from separate geologic maps of varying scales, emphasis, and quality. Most locations in Idaho have original geologic mapping available but the scales vary greatly. A compilation map is considered a "work in progress" because it can always be improved with the addition of better mapping. To determine the quality of data within a digital compilation it is critical to be able to track the individual geologic maps. To meet this requirement all entities within our geologic map coverages can be linked to metadata via a reference identifier. (For complete information about the data set, see the metadata database files) The geologic data presented here are intended for use at a maximum scale of 1:24000-1:125,000 (depending on the mapping source). The data should not be used for site-specific purposes. INTRODUCTION The first reconnaissance geologic map of much of the area in the Clearwater National Forest (Figure 1) was published by Anderson (1930), who also summarized previous work. For many years, Heitanen (1962, 1963a, 1963b, 1968, 1969, 1984) studied the rocks near the northwestern margin of the forest. Rocks along the southern boundary of the forest are covered by maps of the Selway-Bitterroot Wilderness area (Greenwood and Morrison, 1973; Toth, 1983a, and related reports). Recent work by the Idaho Geological Survey (Lewis and others, 1992a, 1992b) covers much of the forest at a scale of 1:100,000. The following discussion accompanies the geologic map compilation of the Clearwater National Forest (Headquarters, Missoula West, Kooskia, and Hamilton 1:100,000 quadrangles) generated under U.S. Forest Service Contract No. FS-01-05-95-5. STRATIGRAPHY SEDIMENTARY AND METASEDIMENTARY ROCKS INTRODUCTION Much of northern Idaho is underlain by the Middle Proterozoic Belt Supergroup (Figures 2 and 3). Units of the Belt Supergroup in the Clearwater National Forest include the Prichard Formation, the Ravalli Group, and the Wallace Formation (Winston, 1986a). The Prichard is over 12,000 feet thick (Hobbs and others, 1965) and is composed of fine-grained quartzite, siltite, and argillite (Cressman, 1985, 1989). The Ravalli Group includes the quartzite and argillite of the Burke Formation (Boyce, 1973; Winston, 1986b), the cross-bedded quartzite of the Revett Formation (Mauk, 1985; Boyce, 1973), and the purple and green argillite of the St. RegisFormation (Boyce, 1973; Winston, 1986b). The thicknesses of these units are: Burke Formation, 2,200-3,000 feet; Revett Formation, 1,200-3,400 feet; and St. Regis Formation, 1,400-2,000 feet (Hobbs and others, 1965). The Wallace Formation consists of a mixed sequence of siliciclastic and carbonate rocks (Grotzinger, 1981, 1986; Winston, 1986b). The upper member of the Wallace Formation, as mapped in Idaho, correlates with the lower two units in the overlying Missoula Group (Lemoine and Winston, 1986; Lewis and others, 1992a, 1992b). Metamorphosed equivalents of the Belt Supergroup have been mapped southward from the Coeur d'Alene area to the Elk City region by Hietanen (1963, 1968, 1984), Harrison (1984; Harrison and others, 1986), Reid and others (1981), and others. Recent mapping by the Idaho Geological Survey (Lewis and others, 1990; Lewis and others, 1992a; 1992b) in the Hamilton and Elk City 1°x2° quadrangles has shown that most of the Belt Supergroup is represented in the Clearwater National Forest (Lewis and others, 1992b). The pre-Belt Boehls Butte Formation, consisting of at least 3,600 feet of interlayered quartzite, schist, and anorthosite, is present below metamorphosed equivalents of the Prichard Formation in the Boehls Butte area (Hietanen, 1969, 1984). The Precambrian metasedimentary rocks in the Nezperce National Forest were subdivided into four lithologic sequences. These are: 1) Syringa metamorphic sequence, 2) the Elk City metamorphic sequence, 3) the Meadow Creek metamorphic sequence, and 4) the Wallace Formation of the Belt Supergroup. Each lithologic sequence consists of as many as three map units, which are based on the predominant rock type in a given area (Lewis and others, 1996). The Syringa sequence extends northward into the Clearwater National Forest. BOEHLS BUTTE FORMATION The oldest rocks in the Clearwater National Forest are in the Boehls Butte Formation, which consists of interlayered quartzite, schist, and anorthosite (Heitanen, 1969, 1984). (Most of this unit is adjacent to, but outside, the forest boundary.) The high aluminum content of the rocks, the locally abundant plagioclase, and the high carbonate content of the original rocks distinguish these rocks from the Lower Prichard Formation (Hietanen, 1969). The Boehls Butte Formation probably originated as an interbedded sequence of limestone, dolomite, aluminum-rich shale, and quartzite (Hietanen, 1963a). The rocks were metamorphosed at temperatures around 580°C. and pressures of about 5 kilobars (equivalent to 18 kilometers of overburden) (Heitanen, 1984). The origin of the labradorite-anorthiteanorthosite is a subject of debate. Nord (1973) believed that it originated by partial melting of an anorthite-rich metamorphic rock or as a crystal-rich labradorite intrusion low in mafic minerals. Juras (1974) also suggested an igneous origin, followed by intense shearing. On the other hand, Heitanen (1963a, 1984) proposed that the anorthosite was formed by metasomatism of limestone layers interbedded with aluminum-rich shale. Sodium-rich solutions introduced during the later stages of metamorphism altered the rocks to their present composition (Hietanen, 1969, 1984). SYRINGA METAMORPHIC SEQUENCE The Syringa metamorphic sequence consists of coarse-grained quartz-mica schist, quartzite, and calc-silicate rocks that are interbedded on a scale of decimeters. Locally the schist contains abundant sillimanite (in the northeast nearest to the Bitterroot lobe) or kyanite (west of Lowell; Van Noy and others, 1970). Extreme recrystallization has obliterated all sedimentary structures in these rocks. Rocks of the Syringa sequence near Lowell have been interpreted as an east-facing stratigraphic sequence that included the Prichard Formation, the Ravalli Group, and the Wallace Formation (Morrison, 1968; Reid and others, 1973). Thin beds of calc-silicate rock throughout the Syringa sequence distinguishes these rocks from either the Ravalli Group or the Prichard Formation. Quartzite is only abundant in the western part of the Syringa section, well below where it would occur if the Ravalli Group was represented, and is not thick enough to be part of the Ravalli Group. Also missing from the Syringa sequence are the thick mafic sills (Wishard and Purcell sills) that characterize the lower and middle Prichard to the north (Finch and Baldwin, 1984; Cressman, 1989). Correlation of the Syringa sequence with the Missoula Group (which contains units above the Wallace Formation) is also unlikely; high-grade metamorphic equivalents of the Missoula Group should consist of muscovitic schist and thick intervals of clean quartzite, both of which are lacking in the Syringa sequence. If the Syringa sequence extends to the northwest beneath the Columbia River Basalt Group, it might correlate with the northeastern part of the Orofino Series (Anderson, 1930; Davidson, 1990). The Syringa sequence may also correlate with the Boehls Butte Formation (Earl Bennett, 1996, personal communication). Clearly, stratigraphic relations between the Syringa sequence and other units in the area, as well as relations within the sequence itself, remain uncertain (Lewis and others, 1996). Preliminary geochemical results from schists in the Syringa sequence indicate that it may be composed of two groups of rocks, a high strontium(greater than 300 ppm) subgroup east of Lowell and a low strontium (less than 120 ppm) subgroup west of Lowell. The strontium concentration in the eastern rocks is distinctly different from that of the argillites of the upper Wallace Formation and the schists of the Prichard Formation (Harrison and Hamilton, 1971). Small bodies of pyroxenite and dunite are distributed in a northwest-southeast zone within the Syringa rocks from northwest to southeast of Lowell, roughly between the eastern and western divisions of the Syringa sequence. These ultramafic bodies may lie in an unmapped, possibly deep fault zone (or zones) between distinct parts of the Syringa sequence (Lewis and others, 1996). These rocks are younger than the Syringa sequence because similar ultramafic bodies also occur in the Riggins Group (Earl Bennett, 1996, personal communication). BELT SUPERGROUP Rocks of the Middle Proterozoic Belt Supergroup underlie much of the Clearwater National Forest. In most areas, the rocks have been metamorphosed to greenschist facies, but in some places, the metamorphic grade is much higher, making correlation with less metamorphosed sections speculative. However, metamorphosed equivalents of the Belt Supergroup have been mapped southward from the Coeur d'Alene area to the Elk City region by Hietanen (1963a, 1963b, 1968, 1984), Harrison (1984; Harrison and others, 1986), Reid and others (1981), and other workers. Recent mapping by the Idaho Geological Survey (Lewis and others, 1990; Lewis and others, 1992a, 1992b) in the Hamilton and Elk City 1°x2° quadrangles has shown that most of the Belt Supergroup is represented in the area. The southernmost exposures of these rocks have been metamorphosed to the amphibolite facies (Lewis and others, 1993). An overview of Belt stratigraphy and correlation is given in Winston (1986a). Although no significant mineral deposits have been discovered within the forest boundaries, major ore deposits do occur in rocks of the Belt Supergroup, most notably the lead-zinc-silver deposits of the Coeur d'Alene district. In spite of their economic importance and despite the detail in which some of the formations have been studied, major questions remain unanswered about the genesis of these deposits. Several models have been proposed for the depositional and tectonic setting of the Belt Supergroup rocks in Idaho and adjacent areas. These models describe the Belt basin as: 1) an epicratonic reentrant along an open-marine passive margin (Harrison, 1972); 2) an aulacogen formed as thefailed arm of a triple junction (Stewart, 1976; Harrison and others, 1974); 3) an inland sea or intracontinental rift basin (Winston and others, 1984; Winston, 1986b; Winston, 1986c; Winston and Link, 1993); 4) an incompletely closed suture or back-arc basin (Hoffman, 1988, 1989); or 5) a meteorite impact crater (Sears and Alt, 1989). Each of these models explains certain aspects of the Belt basin, but none is completely satisfactory. Separation of a continental-size landmass, which was one of the source areas for units in the Belt Supergroup, from the North American craton may have begun around 1.8 Ga (Hughes, 1983) or around 1.5 Ga (Sears and Price, 1978). Plate reconstructions which match the Siberian and North American cratons show a good correlation between coeval structures across the rifted margins (Sears and Price, 1978). More recent work matches major structural zones in western North American with similar structures across the continental margins of Antarctica and Australia (Moores, 1991; Dalziel, 1991; Ross and others, 1992; Brookfield, 1993). The western landmass, like the North American craton, was probably composed of plutonic and metamorphic rocks of both Archean and Proterozoic age (Lopez, 1981). The average age of the source material for the Belt Supergroup is 2.0 0.3 Ga (Frost and Winston, 1987), significantly younger than the greater than 2.5 Ga age of the adjacent Wyoming province (Hoffman, 1989). Prichard Formation The Prichard Formation is the oldest unit in the Belt Supergroup. In many areas, it has been regionally metamorphosed to greenschist through amphibolite facies. The rocks were originally graywacke composed of up to one-third feldspar with an unknown percentage of lithic fragments (now unrecognizable due to recrystallization), making the original rocks lithic wackes or feldspathic wackes (Cressman, 1989). The Prichard is interpreted as a deep-water turbidite deposit that accumulated in a northwest-trending basin and was derived from southern and western sources. The rocks show evidence of two cycles of deep- to shallow-water deposition, indicating the basin filled twice during Prichard time (Cressman, 1985, 1989). Winston and others (1984) suggested the Prichard Formation was deposited in an enclosed, stratified lake or inland sea, noting that turbidites are not confined to marine environments. The age of the Prichard Formation is not well constrained. Rocks beneath the Prichard have been dated at 1,576 13 Ma (Hauser LakeGneiss; Evans and Fischer, 1986) and xenocrystic zircons from the plutonic rocks have yielded U-Pb upper-intercept ages between 1,625 (Toth and Stacey, 1992) and 2,349 Ma (Bickford and others, 1981). This places the maximum age of the Prichard at less than 1,576 Ma. The Crossport C sill (one of the Purcell sills) intruded the middle of the Prichard at 1,433 10 Ma (Zartman and others, 1982). A date of 1,330 45 Ma on metamorphic biotite in the upper Prichard (Obradovich and Peterman, 1968) gives a minimum age for the formation. The base of the Prichard is not exposed. Although no major ore deposits occur in this formation in the Clearwater National Forest, the Prichard is of considerable economic interest. In British Columbia, it is correlated with the Aldridge Formation, which hosts the Sullivan lead-zinc-silver deposit (Cressman, 1989). The Middle Prichard quartzite in the Pine Creek area of the Coeur d'Alene district may contain vestiges of stratabound zinc-lead-silver deposits. Syngenetic stratiform zinc-lead-silver mineralization from the Prichard may have been mobilized to form the Bluebird veins of the Bunker Hill mine and other mines around Burke (Bennett, 1984). Rocks mapped as Prichard Formation in the Headquarters area are coarse-grained mica schist, biotite gneiss, and biotite-muscovite schist containing garnet and sillimanite (Heitanen, 1963b). Light-colored, coarse- to medium-grained quartzite is also present in the area east of Boehls Butte (Heitanen, 1963a). Muscovite-biotite gneiss, coarsely recrystallized quartzite and micaceous quartzite, and quartz-mica schist with varying proportions of biotite and muscovite have been tentatively correlated with the Prichard Formation in the area around the Upper North Fork of the Clearwater River (Heitanen, 1968; Lewis and others, 1992a). Ravalli Group The Ravalli Group is composed of the Burke, Revett, and St. Regis formations. These rocks were deposited in relatively shallow water above the Prichard Formation (Winston, 1986b; Mauk, 1985; Bowden, 1977; Greene, 1984; Alleman, 1983). The Gulf of California (Boyce, 1973) or the Colorado River delta (Bowden, 1977) may be appropriate modern analogues for the Ravalli Group. In the Colorado River delta, the finer-grained sediments form a buffer between the flood-plain environment and the intertidal zone (Bowden, 1977). A combination of the braided stream/tidal flat and beach/barrier island models may explain the features of the Ravalli Group in some areas (Clough, 1981). The quartzite and argillite of the Burke Formation may have been deposited below wave base on the distal portion of a prograding delta front(Boyce, 1973) or on an alluvial apron which contained both braided-stream and sheetflood deposits (Conner and others, 1984). Water depths were shallower to the west (in Idaho) than to the east (Mumma and others, 1982), and sediment was derived from source areas to the south and west (Winston, 1986b). The white, cross-bedded quartzite of the Revett Formation formed in a fluviodeltaic environment (Mauk, 1985). Sandy tidal flat and channel-mouth bar facies (Boyce, 1973) and sizable barrier bars are present locally (Mumma and others, 1982). The coarser-grained rocks were transported by a braided stream system characterized by periodic sedimentation and rapid changes in stream flow (Bowden, 1977; Greene, 1984). The finer-grained rocks are overbank deposits. Some exposures of the Revett show compound cross-bedding typical of eolian deposits (Garlick, 1988). The Revett fluviodeltaic complex has several major lobes (White and others, 1984). The Revett fluvial system had high flood peaks and nearly instantaneous runoff following major storms (Greene, 1984). The source area was to the south and southwest (Alleman, 1983; Greene, 1984). Local bimodal current patterns probably reflect tidal action (Mauk, 1985). Copper-silver deposits in the Revett Formation, which occur in the Coeur d'Alene district to the north of the Clearwater National Forest and at the Troy Mine (Spar Lake deposit) in northwestern Montana, formed when metals were carried into the basin by the rivers. The metals precipitated as sulfides when the fresh water mixed with the anoxic waters of the Belt sea (Garlick, 1988). The deposits were concentrated in part during diagenesis (Harrison, 1972; Bennett, 1984). Other workers suggest the deposits are replacement veins (Fryklund and Fletcher, 1956; Fryklund, 1963), Precambrian vein deposits remobilized in the Late Cretaceous (Long and others, 1960), or veins formed by metamorphism in the late Precambrian (Leach and others, 1988; Landis and others, 1984). The purple and green argillites of the St. Regis Formation were probably deposited on a delta plain with tidal mud flats (Boyce, 1973; Winston, 1986b), but they have also been described as a deep-water turbidite sequence (Hrabar, 1971). Diverse sedimentary structures, including mudcracks and algal laminations, support shallow-water deposition. Vegetation had not evolved during the Precambrian. Without plants to stabilize the sediments on the delta plain, it would become a broad mud flat or a strand plain (Boyce, 1973). Units in the Elk City region mapped as the Ravalli Group contain a greater proportion of quartzite than equivalent units farther north. These rocks were possibly deposited near the southwestern margin of the basin (Burmester and others, 1993). In the Headquarters quadrangle, the Revetthas been metamorphosed to coarse-grained quartzite which contains minor amounts of feldspar, biotite, and sillimanite; and rocks equivalent to the St. Regis are laminated biotite-muscovite schist, thin-bedded biotite quartzite, and biotite gneiss (Heitanen, 1963b). In the areas around the Upper North Fork of the Clearwater River and near the headwaters of the Lochsa River, quartzite with interbedded phyllite or schist has been tentatively correlated with the Ravalli Group (Heitanen, 1968; Lewis and others, 1992a, 1992b). Wallace Formation Correlation between the Wallace Formation in Idaho and equivalent rocks to the east in Montana has long been a problem. The Wallace Formation in Montana corresponds approximately to the lower and middle members of the Wallace, as it has been mapped in Idaho. The upper member of the Wallace Formation, as mapped in Idaho, correlates with the Shepard and Mt. Shields formations, the lower two units in the Missoula Group (Lemoine and Winston, 1986; Lewis and others, 1992a, 1992b). The Wallace Formation is a mixed carbonate-siliciclastic sequence that formed in a shallow-water, restricted environment that was, at times, euxinic. The source of the clastic material was to the south (Harrison, 1984) and west (Winston, 1986b). The Wallace may have formed in a lacustrine environment (Grotzinger, 1981) or a microtidal, restricted marine basin (Grotzinger, 1986). Winston (1986b) made detailed comparisons of the sedimentary facies in the Wallace and the Green River Formations. The lower member of the Wallace was deposited in a nearshore, shallow-water, euxinic environment (Grotzinger, 1981) or on a peritidal slope or a subtidal basin (Wallace and others, 1993). The black argillite and dolomitic siltite couplets of the middle member were deposited in shallower water (Grotzinger, 1986), possibly by traction currents moving across the shelf (Wallace and others, 1993). A zone of carbonate/siliciclastic slumps and breccias at the top of the middle member may reflect a widespread tectonic event (Grotzinger, 1986). Diamictites are also present at this horizon in rocks correlated with the Wallace Formation in the Elk City area (Burmester and others, 1993) and in similar rocks in the upper Lochsa and North Fork of the Clearwater drainages (Lewis and others, 1992a, 1992b). In the Headquarters quadrangle, rocks of the Wallace Formation have been altered to biotite-garnet-sillimanite schist, biotite gneiss, diopside-plagioclase gneiss, and quartzite (Heitanen, 1963b). In the Upper North Fork of the Clearwater River, these rocks have been mapped as the lower and middle members of the Wallace Formation and the Missoula Group(undivided). In the Pole Mountain-Five Lakes Butte and Chamberlain Mountain-Gospel Hill areas, the metamorphic grade in the Missoula Group rocks increases to the south and southwest (Lewis and others, 1992a). Mount Shields Formation Units 1-3 of the Mount Shields Formation are episodic flood deposits that accumulated in alluvial fan, sand flat, and playa margin environments (Slover and Winston, 1986). Carbonates formed during periods of highstand, when most of the basin was submerged (Winston, 1986b). The Mount Shields Formation has been mapped in Idaho near the headwaters of the Lochsa and North Fork of the Clearwater Rivers (Lewis and others, 1992a, 1992b). RIGGINS GROUP South of the Clearwater National Forest, the Riggins Group (as defined by Hamilton (1963)) is composed of the Fiddle Creek Schist, the Lightning Creek Schist, the Squaw Creek Schist, and associated rocks. The green and white schist that makes up the Fiddle Creek Schist was formed by the metamorphism of massive flows and tuffs of intermediate and silicic composition. The greenschists of the Lightning Creek Schist were originally lava, tuff, and agglomerate (Hamilton, 1963). In some places, metaperidotite or the Berg Creek Amphibolite is found between the Lightning Creek Schist and the Squaw Creek Schist (Onash, 1977; Hamilton, 1963). The gray phyllite and schist of the Squaw Creek Schist were probably derived from volcaniclastic rocks (Hamilton, 1963). The age of the Riggins Group is unknown. However, these rocks appear to be part of the accreted Blue Mountains island-arc terrane and may be higher-grade metamorphic equivalents of the Seven Devils Group (Lund and Snee, 1988; Lund and others, 1993). This conclusion is supported by trace element analyses of Riggins Group and equivalent rocks reported by Davidson (1990), Hoover (1986), and Lewis and others (1996). West of the Woodrat Mountain fault, rocks correlated with the Riggins Group are medium- to fine-grained garnet-biotite-hornblende gneiss, hornblende-biotite schist, and calc-silicate quartzite. The calc-silicate quartzite contains variable amounts of plagioclase, hornblende, diopside, epidote, and garnet. To the southwest, at 46°00N, exposures of the Riggins Group consist of fine-grained, garnetiferous hornblende-biotite schistand gneiss, and garnet-diopside-hornblende quartzite (Lewis and others, 1996). Reid and others (1973) noted that the rocks west of the Woodrat Mountain fault are similar to rocks near Orofino that have been termed the Orofino Series (Anderson, 1930; Hietanen, 1962). The rocks in the Orofino area were thrust against the edge of the continent during the accretion of the Blue Mountains arc (Davidson, 1990). QUATERNARY DEPOSITS Alluvial deposits are present in modern drainages, and landslide deposits have been mapped in some areas. Glacial deposits include lateral and ground moraines, till, and outwash gravels (Lewis and others, 1992a, 1992b). IGNEOUS ROCKS Basic sills (known as the Purcell or Wishard sills) intruded the Belt Supergroup rocks at 1,073-1,200 Ma and at about 750-830 Ma (Reynolds, 1984). In the Boehls Butte area, gabbroic sills and dikes (now recrystallized to amphibolite and garnet amphibolite) may have been emplaced during one of these events (Heitanen, 1984). Other metamorphosed mafic dikes were mapped in the areas of the North Fork of the Clearwater River and in the Lochsa river area (Lewis and others, 1992a, 1992b). Some of these dikes may be Precambrian in age, but most are likely Permo-Triassic (Earl Bennett, 1996, personal communication). IDAHO BATHOLITH Overview Most of the intrusive rocks in central Idaho are related to the Idaho batholith, a large granitoid body that is exposed through most of central Idaho. The Idaho batholith is divided into two lobes, the Atlanta lobe (southern) and the Bitterroot lobe (northern), by a northwest-trending belt of Precambrian metasedimentary rocks (Figure 4). These metasediments have been variously labeled the Lemhi arch (Sloss, 1954; Ruppel, 1986) and the Salmon River arch (Armstrong, 1975b), and have been cited as the source area for many of the Precambrian and Paleozoic units in south-central Idaho. Skipp (1985) showed that the Salmon River arch was an effect of the stacking of thrust plates during Late Cretaceous thrusting. Rocks exposed along the southern margin of the Bitterroot lobe are below the intrusive rocks (Wiswall and Hyndman, 1987) and may be similar to the Belt and pre-Belt rocks that were melted to form the batholith. The bulk of the rocks in the Atlanta Lobe are older than the majority of the rocks in the Bitterroot Lobe (Toth, 1987; Toth and Stacey, 1992). Intrusion of the batholith was caused by subduction related to accretion of the Wallowa/Seven Devils terrane starting about 120 Ma (Vallier and Brooks, 1987; Hyndman and Foster, 1988). Idaho batholith (Bitterroot lobe) The Bitterroot lobe of the Idaho batholith consists of migmatite zones, Cretaceous to Paleocene plutons of varying compositions, and crosscutting Tertiary intrusive rocks (Vallier and Brooks, 1987). Small intrusions of hornblende-diorite tonalite and quartz diorite are the oldest rocks in the Bitterroot lobe (Toth, 1987). Migmatite zones are located along the northern, western, and southern borders of the Bitterroot lobe and scattered within the main body of the batholith (Bittner-Gaber, 1983). The bulk of the Bitterroot lobe is made up of large granodiorite and monzogranodiorite plutons (Toth, 1987). Part of the Bitterroot lobe has been interpreted as a metamorphic core complex (Hyndman, 1980). Reid (1984, 1987) summarizes the relevant studies on the structure of the batholith and its border zone. A detailed petrographic and structural study of a strip across the north-central Bitterroot lobe is contained in Reid (1984). On the southwestern margin, a tonalite body shows a strong flow foliation near the edge of the intrusion. In the same area, concordant sheets of tonalite gneiss intruded the country rock. Both the tonalite and the tonalite gneiss are close to the same age (Reid, 1987). However, the ages of these rocks is variously given as 94 Ma (Toth and Stacey, 1992), between 74 and 55 Ma (Bickford and others, 1981), between 85 and 70 Ma (Wiswall and Hyndman, 1987), or between 100 and 80 Ma (Toth, 1987). Criss and Fleck (1987) discuss the factors which complicate dating of the Bitterroot lobe. They show that plutons which intruded the suture zone between the Blue Mountains terrane and the Precambrian craton range from 87 to 75 Ma; however, more recent work dates the intrusion of these tonalitic plutons at 93 Ma (Snee and others, 1995). The plutons of the Bitterroot lobe were intruded after that time (Criss and Fleck, 1987). The tonalite probably formed by partial melting of material in the upper mantle,followed by assimilation of Precambrian basement rocks as the magma moved through the crust (Toth, 1987). The magmas for the tonalites were probably generated at depths between 20 and 25 km (Hyndman and others, 1988). Large migmatite screens separate the tonalite from the main body of the Bitterroot lobe (Toth, 1987). Tonalitic and dioritic intrusives that have been mapped and described include the tonalite of Coolwater Ridge (Lewis and others, 1992b; includes the Coolwater orthogneiss of Morrison, 1968) and the quartz diorite of Junction Mountain (Childs, 1982). Megacrystic tonalite forms part of the Paradise pluton (Wiswall, 1979; Callahan, 1983; Toth, 1983b). Migmatite zones are concentrated along the border of the Bitterroot lobe, particularly along the northern, western, and southern margins. Migmatite screens are also scattered within the main body of the batholith (Bittner-Gaber, 1983). These rocks show that, prior to intrusion of the batholith, the country rocks were metamorphosed to amphibolite facies (kyanite zone; about 500°C and 10-30 kilometers depth). Intrusion of the early tonalite formed the migmatites by lit-par-lit intrusion, metasomatism, and partial melting of the older rocks. Intrusion of the main-phase granites and granodiorites aligned the migmatite screens parallel to the upward and eastward flow of the magma (Bittner, 1987). Along the northern margin of the Bitterroot lobe, the border zone can be divided into two parts based on the degree of metamorphism of the Belt Supergroup. In the outer zone (metamorphosed to greenschist facies), quartz and calcite veins formed from material mobilized during metamorphism. In the inner zone (metamorphosed to amphibolite facies), most of the granitic rocks were injected into the migmatite zones (Johnson, 1975). In the western and southern parts of the Bitterroot lobe, the migmatite zones may be close to the basal contact of the batholith (Wiswall, 1979; Bittner, 1987). Wiswall and Hyndman (1987) noted the rocks along the Selway River showed a more ductile style of deformation and the presence of anatectic migmatites, from which they inferred that the base of the Bitterroot lobe is exposed along the southwestern border. The large granodiorite and monzogranodiorite plutons that make up the bulk of the Bitterroot lobe were intruded in the latest Cretaceous or Paleocene (Toth, 1987; Toth and Stacey, 1992). A northwest-treading transform, the trans-Idaho discontinuity (Yates, 1968; Taubeneck and Armstrong, 1974), may have controlled where the Bitterroot lobe was emplaced (Bittner, 1987). 40Ar/39Ar dates between 66 and 60 Ma (Criss and Fleck, 1987) may reflect intrusion of the main body of the Bitterroot lobe, although biotite granodiorite along the Lochsa River has produced zircon dates of 71 Ma and 75 Ma (Toth and Stacey, 1992). The large areal extentand general lack of textural and mineralogical variation suggests that the Bitterroot lobe formed from a few extremely large plutons (Wiswall and Hyndman, 1987); however, Toth (1987) notes that detailed mapping may eventually show that the Bitterroot lobe is composed of 20 or more different plutons, each distinguishable by slight differences of mineralogy, texture, or chemistry. The granitic rocks of the batholith are vertically zoned from calcic granodiorite near the base to granite at the top (Reid, 1987). Plutons which contain primary muscovite probably formed by partial melting of metamorphosed Belt or pre-Belt metasedimentary rocks. Other plutons appear to have originated deeper in the crust or to have formed by melting metamorphosed volcanic rocks (Toth, 1987). The magmas for these rocks may have been generated at depths of around 45 kilometers (Hyndman and others, 1988), and the magmas were formed from mixtures of melted lower crust material and Precambrian wall rocks (Fleck and Criss, 1985). The main phases of the Bitterroot lobe were emplaced as diapirs which were emplaced close to their source areas in the lower crust (Wiswall and Hyndman, 1987). A minimum depth of emplacement for these rocks was probably 15 to 20 kilometers (Hyndman, 1983). When the upper parts of the diapirs quit rising before the lower parts, the tops of the plutons spread laterally to form mushroom-shaped bodies (Wiswall, 1979; Wiswall and Hyndman, 1987). The eastward spread of the sheet-like mass of granitic magma may have been controlled by a low-angle thrust fault near its base (Reid, 1987). Xenoliths and migmatite screens were rotated into alignment along an east-west trend during the upward and eastward flow of the partially crystallized granite (Bittner, 1987). Upward arching of the secondary flow lineation in the granitic rocks shows that the batholith must have been 30 kilometers or more thick before the folding occurred (Reid, 1987). Granodioritic plutons that have been mapped in the Bitterroot lobe include the Brushy Fork (Nold, 1968; Lewis and others, 1992b), White Sand Creek (Nold, 1968; Lewis and others, 1992b), and Skookum Butte (Nold, 1968, 1974; Lewis and others, 1992b) plutons, the Tom Beal Park granite (Williams, 1977), and part of the Grave Peak pluton (Toth, 1987). Muscovite-biotite granite plutons include the Boulder Creek pluton (Williams, 1977) and part of the Grave Peak pluton (Toth, 1987). In the Bitterroot lobe, most mineral deposits or occurrences are near the border of the Bitterroot lobe or are close to roof pendants. Mineralization is related to deep-level hydrothermal activity associated with the emplacement of the main-phase plutons. Unlike the Atlanta lobe, most of the Eocene hydrothermal systems in the Bitterroot lobe were relatively weak and had only minor mineralization associated with them (Criss and Fleck, 1987). Intrusion of the younger plutons in the Bitterroot lobe continued into the Paleocene (Criss and Fleck, 1987). Rocks in the northern part of the Bitterroot lobe were metamorphosed after intrusion at a pressure of two to three kilobars and at a temperature near the greenschist-amphibolite facies boundary (approximately 550°-600°C). This metamorphic event did not affect the Tertiary granites (Williams, 1977). The Paradise pluton was intruded at the start of a period of regional extension (Toth, 1987). TERTIARY INTRUSIVE ROCKS In Idaho, the plutonic rocks of Eocene age belong to two suites, one of biotite granite and the other of quartz monzodiorite (Bennett and Knowles, 1985; Lewis and Kiilsgaard, 1991). These rocks are part of the Challis magmatic episode, which affected a broad area from British Columbia to Wyoming (Armstrong, 1974; Hyndman and Williams, 1977; Bennett, 1980; Moye and others, 1988). The Eocene plutons are epizonal and are associated with numerous andesitic to rhyolitic dike swarms (Lewis and others, in preparation). K-Ar age determinations for these plutons in the Clearwater National Forest range from 44 to 48 Ma (Greenwood and Morrison, 1973; Armstrong, 1975a; Criss and Fleck, 1987). Granitic plutons of Eocene age surround the Bitterroot lobe on the south, southwest, and north sides (Toth, 1987). These plutons were intruded to very shallow levels (as little as 1.5 km) and locally they intrude their own volcanic ejecta. The Eocene granites formed by partial melting of lower crust rocks that had previously been melted to produce granite (Toth, 1987), and they were emplaced during a period of east-west extension (Motzer, 1985; Rehn and Lund, 1981). Among these granitic intrusives are the Bungalow (Hietanen, 1984; Reynolds, 1991) and Whistling Pig (Lund, 1980; Toth, 1983a; Motzer, 1985) plutons, the Horseshoe Lake (Lewis and others, 1992a) stock, and the Lolo Hot Springs batholith (Nold, 1968, 1974; Simpson, 1985). Reynolds (1991) concluded that the Bungalow pluton was emplaced along an existing fault system. Shallow hydrothermal systems associated with the emplacement of the Eocene granites affected large areas surrounding the plutons, but did not produce many significant ore deposits (Criss and Fleck, 1987); many of these systems in the Clearwater National Forest are too deeply eroded to show any mineralization (Earl Bennett, 1996, personal communication). Both Tertiary (Bennett and Knowles, 1985) and Cretaceous (Toth, 1983a) ages have been suggested for tonalitic bodies adjacent to the Tertiary granites in the southern part of the Selway-Bitterroot Wilderness area. Northeast-trending fault systems controlled the emplacement of dacitic to rhyolitic Eocene dike swarms, which typically have northeast trends (Lewis and others, in preparation). Dike swarms are associated with many of the large Tertiary intrusive bodies in the forest. EOCENE VOLCANIC ROCKS A varied section of volcanic rocks of probable Eocene age are preserved in a graben on the west side of the Lolo Hot Springs batholith, (Simpson, 1985; Lewis and others, 1992a). These rocks include rhyolitic tuffs erupted from the Rhodes Peak cauldron, associated volcaniclastic rocks, and andesite dikes and lava flows (Simpson, 1985). Gold occurrences are known to occur in these rocks (Earl Bennett, 1996, personal communication). COLUMBIA RIVER BASALT GROUP In the middle and late Miocene, an immense volume of quartz-tholeiite basalt was erupted to form the Columbia River Basalt Group. Eruptions began in the southeast, and the lava filled the valleys and covered the original topographic surface to a depth of nearly 700 meters (Hooper and Swanson, 1987). The lowest unit in the Columbia River Group is the Imnaha Basalt (exposed to the south of the Clearwater National Forest), which is between 17.0 and 16.5 Ma. The lava erupted from north-northwest trending fissures and covered a deeply dissected topographic surface (Swanson and Wright, 1978, 1981; Hooper and others, 1984; Hooper and Swanson, 1987). In the Clearwater embayment (the remnant of a prism of basalt that extended eastward into west-central Idaho (Bond, 1963)), basalt eruptions repeatedly dammed the ancestral Clearwater River drainages, resulting in alternating lava flows and interbedded sediments (Camp, 1981). The Yakima Basalt Subgroup is composed of the Grande Ronde, the Wanapum, and the Saddle Mountains basalts (Swanson and others, 1979b). The Grande Ronde Basalt makes up more than 85 percent of the Columbia River Group and was erupted between about 16.5 and 14.5 Ma (Hooper and Swanson, 1987). It is equivalent to most of Bond's (1963) "upper basalt" in the Clearwater embayment. The flows range in thickness from less than 1 meter to more than 100 meters, and few are distinctive enough in the field to serve as marker units (Swanson and others, 1979b). Many of the flowsnear margin of the basin are interbedded with subarkosic sediments; these flows may be up to 120 meters thick. In the areas where the Grande Ronde Basalt laps onto the older, rugged topography, the flows at the contact may be pillowed (Swanson and others, 1979a). The only reliable means for subdividing the stratigraphy of the Grande Ronde Basalt is by magnetic polarity (Swanson and others, 1979b; Hooper and others, 1979). The Wanapum Basalt consists of a series of generally medium-grained, olivine-bearing flows, most of which have high amounts of iron and titanium. This formation is divided into four members (Swanson and others, 1979b), not all of which are present in the Clearwater National Forest. Camp (1981) proposed the basalt of Feary Creek as an informal member of the Wanapum Basalt in the Frenchman Springs member. The basalt of Feary Creek consists of two or more flows of fine- to medium-grained basalt that has scattered large phenocrysts of plagioclase and olivine as a common mineral in the groundmass. The basalt intrudes subarkosic sandstone and siltstone, and the unit is found only west of Headquarters in the North Fork of the Clearwater River (Swanson and others, 1979a; Camp, 1981). The Priest Rapids Member of the Wanapum Basalt is one of the most extensive stratigraphic units in the Columbia River Basalt Group (Camp, 1981). At least one of the flows mapped by Bond (1963) as the Lolo Creek flow belongs to this member (Swanson and others, 1979b). The basalt is fine- to coarse-grained, and flows of two distinct chemical compositions are included in the unit. Rocks of the Priest Rapids Member commonly overlie and intrude weakly lithified subarkosic sandstone, siltstone, and claystone near edge of plateau (Swanson and others, 1979a). Feeder dikes for the unit occur in a northwest-trending zone that extends from Slate Creek (in the Nez Perce National Forest) through Orofino and that may be as much as 160 kilometers long (Camp, 1981). The Saddle Mountain Basalt erupted between 13.5 0.5 Ma and 6 Ma (McKee and others, 1977), and the unit contains flows of diverse chemistry, petrography, and paleomagnetic polarity (Swanson and others, 1979b). Members of the Saddle Mountain Basalt present in and near the Clearwater National Forest include the Wilbur Creek Member, the basalt of Lapwai, the Asotin Member, the basalt of Weippe, and the basalt of Grangeville. The Wilbur Creek Member is composed of fine-grained basalt with sparse, small plagioclase phenocrysts (Swanson and others, 1979a, 1979b). The unit is exposed in the Lewiston Basin and along the North Fork of the Clearwater River (Camp, 1981). The basalt of Lapwai is the uppermost flow of Wilbur Creek Member (Swanson and others, 1979a). This flow is distinguished by higher MgO and lower SiO2 than the rest of the member (Swanson and others, 1981). The Asotin Member contains sparse phenocrysts ofplagioclase and olivine and is extensively exposed east of Lewiston (Swanson and others, 1979a, 1979b; Camp, 1981). The basalt of Lapwai may have originated by mixing of the magmas that produced the Wilbur Creek and Asotin members (Hooper, 1985). The basalt of Weippe is medium- to coarse-grained and is similar petrographically and chemically to rocks in the Pomona Member; however, the two units are separated by 35 kilometers and the correlation has not been proven (Swanson and others, 1979a; Camp, 1981). Feeder dikes for the basalt of Weippe occur in the upper North Fork of the Clearwater River, and the flow fills an ancestral canyon of the North Fork to a depth of 400 meters (Camp, 1981). The basalt of Grangeville is medium- to coarse-grained and has sparse plagioclase and abundant olivine phenocrysts. It occurs only in the southeast Clearwater embayment southwest of the Clearwater National Forest boundary (Swanson and others, 1979a). Many of the units in the Saddle Mountain Basalt, at least on a local scale, fill canyons cut in early flows and are interbedded with fluvial and lacustrine sediments (Camp, 1981). STRUCTURAL GEOLOGY METAMORPHISM AND DEFORMATION The metasedimentary rocks on the western border of the Selway-Bitterroot Wilderness Area have been deformed at least four times. The first period of deformation was probably in the Precambrian, and the three later periods of deformation were related to different stages of batholith emplacement (Toth, 1983a; Hyndman and others, 1988). Most of the rocks in the Belt Supergroup were subjected to greenschist-facies burial metamorphism in the Precambrian (Hyndman and Foster, 1988). The oldest recognizable structures in the Elk City and Lowell areas are tight, recumbent isoclinal folds with knife-sharp crests and well-developed axial plane schistosity. Recrystallization at amphibolite grade probably accompanied this deformation. These folds were deformed by second-generation isoclinal folds that have a general northwesterly trend and an incipient axial plane schistosity. Partial recrystallization, with kyanite and sillimanite as the stable phases, accompanied the formation of the second-generation folds. Relatively open folds deformed all previous structures, accompanied by poorly-developed, retrograde reactions in the greenschist facies. A fourth event was characterized by the formation of kink folds and by the growth of epidote and chlorite (Reid, 1959; Greenwood, 1967; Morrison, 1968; Reid and others, 1973). Recent work in the Elk City area by Dragovich and Burmester (in preparation) recognizes three major fold events, which are similar in style to those described in earlier work. The first two events account for the schistosity in the rocks and for most of the observed folds (Lewis and others, in preparation). Both events were originally thought to be Precambrian in age (Reid and others, 1973), but the second, more easily recognized event involved synkinematic intrusion of the early phases of the Idaho batholith (Dragovich and Burmester, in preparation). In the country rocks adjacent to the north-central part of the Bitterroot lobe, Reid (1984, 1987) identified three superimposed sets of folds. First were small isoclinal folds, followed by conical folds that deform the axial-plane schistocity of the earlier folds. Third-generation folds appear to be a major drag-fold set formed late in the rise of the batholith. All three fold sets apparently developed during a single metamorphic event in the hornblende hornfels facies. The accompanying injection and metamorphism of igneous material suggests the thermal and mechanical energy came from the emplacement of the batholith. Five deformational events are recorded in the migmatite zones in the Bitterroot lobe (Bittner-Gaber, 1983). The first folding event was accompanied by kyanite-zone metamorphism. The second event, characterized by flow foliations and lineations and by hornblende hornfels contact metamorphism, marked the emplacement of the Bitterroot lobe. Sillimanite-muscovite facies metamorphism and open northwest-trending folds accompanied the third event, and the development of post-crystallization shear zones and intense mylonitization characterized the fourth event. Finally, the eastern batholith was faulted and arched, and earlier structures were refolded. In the northeastern part of the Selway-Bitterroot Wilderness Area, the country rocks recrystallized in the sillimanite zone of the amphibolite facies, probably at the same time that the tonalites were intruded, and the schistocity was folded into close to tight folds. The foliation and folding in the tonalitic gneiss in this area are not developed in the surrounding country rock, but appear to be related to the emplacement of the tonalite. The granodiorite of the Bitterroot lobe shows a blastomylonitic foliation (Bradley, 1981). Nold (1968) recorded at least four periods of deformation along the northeastern border of the Idaho batholith in the vicinity of Lolo Pass. Isoclinal folds are present in the metasedimentary rocks in the Bungalow area. Lineations in the rocks mark a second period of folding. Axes of the first fold set were mainly easterly or southeasterly, and the axes of the later folds trended northeast (Heitanen, 1963b). Juras (1974) reported ten deformational events in the Boehls Butte area. In theHeadquarters area, the Belt Supergroup has been metamorphosed to the sillimanite or the sillimanite-muscovite subfacies of the amphibolite facies contemporaneous with folding (Heitanen, 1962; Heitanen, 1963b). This zone of highly metamorphosed rocks around the batholith extends more than 20 miles north and northwest from the Headquarters quadrangle. Quartz diorite was emplaced after the main phase of metamorphism. Metasomatic development of hornblende and plagioclase occurred after folding and was genetically related to the quartz diorite (Heitanen, 1962). Rocks in the Mallard Peak area that are closer to the contact with the Idaho batholith are metamorphosed to higher grades than the rocks farther from the contact. Two periods of recrystallization are recorded in the rocks: one synkinematic with the early stages of emplacement of the batholith and one postkinematic (Heitanen, 1968, 1984). FAULTS Low-Angle Faults Several low- to moderate-angle faults are present in the northern part of the Clearwater National Forest. All were mapped as thrust faults, and some show the older-over-younger relationships that are characteristic of thrust faults. Notable exceptions are the fault at the base of the lower member of the Wallace Formation in the north-central part of the forest and the fault at the base of the Missoula Group in the eastern part of the forest along the Idaho-Montana border (Lewis and others, 1992a). The fault at the base of the Wallace Formation is best exposed along the upper part of the North Fork of the Clearwater River, 3 miles west of Hoodoo Pass. At this location, the bedding of both plates is truncated, and topographic expression indicates that the Wallace Formation is in the upper plate. If the quartzite in the lower plate is part of the Ravalli Group (a tentative correlation), then this fault places younger rocks over older. To the south near Trap Point, the relationships are less certain, but the contact is interpreted to be the same younger-over-older fault. Southward near Moose Mountain, this fault becomes tightly folded and overturned to the west (Lewis and others, 1992a). R.E. Kell (in Lewis and others, 1992a) interpreted this fault to be part of a nappe structure. The section of Missoula Group along the Idaho-Montana border is truncated at its base by a nearly horizontal fault that cuts the bedding. Bleached and cleaved rocks of the upper plate overlie sedimentary breccia of the middle Wallace Formation in the lower plate (Lewis and others, 1992a). Although mapped as a thrust, an alternate explanation is that this is a low-angle normal fault (D. Winston in Lewis and others, 1992a). High-Angle Faults A significant structure just southwest of the Clearwater National Forest boundary is the boundary (suture zone) between Precambrian and other continental rocks and the accreted Blue Mountains volcanic arc complex of Permo-Triassic age (Figure 4). Accretion by right-lateral transpressional movement along the suture zone started at about 130 Ma and concluded by 93 Ma (Lund, 1984; Snee and others, 1995). The exact location of this structure in the vicinity of the forest boundary is uncertain because key exposures are covered by younger volcanic rocks (Columbia River Basalt), there are correlation difficulties within the metasedimentary units, and the suture zone is intruded by Cretaceous granodiorite in many places (Lewis and others, 1992b). Numerous north-trending faults are present near the continent-island arc boundary. Although these faults are probably related to the formation of the suture zone, movement has been recurrent, as shown by dip-slip offset of the Miocene Columbia River Basalt along many of these structures. This latest movement is interpreted as incipient Basin and Range-style faulting, which is not as pronounced in the northern part of Idaho as it is further south (Lewis and others, in preparation). The Collins Creek fault is one of several high-angle faults in the northwestern part of the forest that have north-south trends. The grain size of the metamorphic rocks increases west of the fault, suggesting that motion was down to the east (Lewis and others, 1992a). Faults with similar orientations include the Cedar Creek and Elk Summit faults in the southeastern part of the forest (Lewis and others, 1992b). A second set of steep faults trends northeast. These fault systems were activated by northwest-southeast extension during Eocene time. These structures were important in controlling the emplacement of Eocene dike swarms and some of the Eocene granite plutons (Lewis and others, in preparation). They also formed grabens in which Eocene volcanic rocks are preserved (Lewis and others, 1992a). This northeast-trending fault set parallels the trans-Challis fault system, which is located 80 kilometers to the southeast (Kiilsgaard and Lewis, 1985; Bennett, 1986; Kiilsgaard and others, 1986). Examples of these faults include the Shale Mountain and the Papoose Saddle faults, near the east-central boundary of the forest, and the Holly Creek and Colgate Warm Springs faults, in the south-central part of the forests (Lewis and others, 1992b). The Kelly Forks fault is a high-angle structure that trends northwest-southeast across central part of the Clearwater National Forest. Its strike is parallel to that of the Lewis and Clark line, which is mapped to the north (Harrison and others, 1986). Childs (1982) and R.E. Kell (in Lewis and others, 1992a) have postulated that left-lateral movement along this structure was followed by minor right-lateral motion. Complex dip-slip motion may also have occurred. The presence of metasedimentary rocks equivalent to the Wallace Formation south of the fault compared with the predominance of rocks correlated with the Prichard Formation immediately north of the fault suggests the south side moved downward relative to the north side. However, the abundance of batholithic rocks on the south side of the fault suggests the opposite sense of motion (Lewis and others, 1992a). In addition, metamorphosed equivalents of the Wallace Formation are the only rocks of the Belt Supergroup that are located south of the Kelly Forks fault (Earl Bennett, 1996, personal communication). An important structure in the southwestern part of the forest is the northwest-trending Glade Creek fault, which marks the southwestern limit of known Belt Supergroup units. This fault is within the trans-Idaho discontinuity (Yates, 1968; Pitz, 1985), a 10-kilometer-wide deformational zone that extends from Glade Creek southwest to Lowell. Extreme flattening across this zone precludes determination of original attitude or motion of the Glade Creek fault. Rocks southwest of the Glade Creek fault were assigned to three metamorphic sequences (Meadow Creek, Syringa, and Elk City), of which only the Syringa sequence is exposed in the Clearwater National Forest. These sequences are of uncertain age and correlation, and their contact relations are poorly understood (Lewis and others, 1992b). Faults that trend east-west include the Cayuse Creek fault in the east-central part of the forest and an unnamed fault north of Cook Mountain in the west-central area. The Cayuse Creek fault separates the Missoula Group from the Wallace Formation, much like the low-angle structure near the Idaho-Montana line. However, its relatively straight trace suggests a steeper dip, so it was mapped as a normal fault. The bedding is truncated at a low angle. The western end of the Cayuse Creek fault is obscured by the intrusion of Eocene quartz syenite. The fault may connect to the Kelly Forks fault or extend (unmapped) to the west toward the fault north of Cook Mountain. A third east-west fault is now occupied by quartz syenite from Hanson Ridge eastward to the Lolo Hot Springs batholith (Lewis and others, 1992a). The Spruce Creek mylonite zone, which is located near the eastern boundary of the Clearwater National Forest, strikes north-south and dipswest. Orientation of s-c surfaces indicates top to the east motion. This zone appears to be the western flank of the Bitterroot dome described by Hyndman (1980) (Lewis and others, 1992b). A zone of mylonite 600 to 1,500 feet thick is exposed to the east of the Clearwater National Forest boundary along the eastern edge of the Bitterroot Mountains in Montana (Toth, 1983a). More than 30 kilometers of relative vertical movement occurred along Bitterroot front mylonite zone as a result of uplift and arching of the batholith (Reid, 1987). The part of the Bitterroot lobe between these mylonite zones was uplifted rapidly in the Eocene and is interpreted as a metamorphic core complex (Hyndman, 1980).</PRE></SPAN><BR /> <SCRIPT>fix(original)</SCRIPT> </DIV> </DIV> <DIV CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Purpose <DIV ID="Purpose" CLASS="pe2" STYLE="display:"> <SPAN CLASS="lt"><PRE ID="original">To allow for display and analysis of resource information</PRE></SPAN><BR /> <SCRIPT>fix(original)</SCRIPT> </DIV> </DIV> <DIV STYLE="text-align:center; color:#6495ED">_________________</DIV><BR /> <DIV CLASS="ph1" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Status of the data <DIV CLASS="pe2" STYLE="display:none"> In work<BR /><I>Data update frequency: </I> As needed<BR /></DIV> </DIV> <BR /> <DIV CLASS="ph1" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Time period for which the data is relevant <DIV CLASS="pe2" STYLE="display:none"> <DIV> <I>Description: </I> <SPAN CLASS="lt"><PRE ID="original">publication date</PRE></SPAN><BR /> <SCRIPT>fix(original)</SCRIPT> </DIV> </DIV> </DIV> <BR /> <DIV CLASS="ph1" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Publication Information <DIV CLASS="pe2" STYLE="display:none"><SPAN CLASS="lt2"> <I>Who created the data: </I>Clearwater National Forest<BR /></SPAN> <DIV><I>Date and time: </I> 2000</DIV> </DIV> </DIV> <DIV STYLE="text-align:center; color:#6495ED">_________________</DIV><BR /> <DIV CLASS="ph1" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Data storage and access information <DIV CLASS="pe2" STYLE="display:none"> <I>File name: </I>rocks_east<BR /> <I>Type of data: </I>vector digital data<BR /> <DIV><I>Location of the data: </I></DIV><DIV><LI STYLE="margin-left:0.2in">\\LTDEGRCVL51\C$\fsfiles\ref\library\gis83\clearwater\geodatabase\soils.gdb</LI></DIV> <I>Data processing environment: </I><SPAN CLASS="lt">Microsoft Windows 2000 Version 5.0 (Build 2195) Service Pack 4; ESRI ArcCatalog 9.2.4.1420</SPAN><BR /> <DIV CLASS="ph1" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Accessing the data <DIV CLASS="pe2" STYLE="display:none"> <I>Data transfer size: </I>0.121 MB<BR /> <BR /> </DIV> </DIV> <DIV CLASS="ph1" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Constraints on accessing and using the data <DIV CLASS="pe2" STYLE="display:none"> <I>Access constraints: </I> <SPAN CLASS="lt">none<BR /></SPAN><DIV> <I>Use constraints: </I> <SPAN CLASS="lt"><PRE ID="original">The Forest Service uses the most current and complete data available. GIS data and product accuracy may vary. They may be: developed from sources of differing accuracy, accurate only at certain scales, based on modeling or interpretation, incomplete while being created or revised, etc. Using GIS products for purposes other than those for which they were created, may yield inaccurate or misleading results. It is highly recommended that before any conclusions or analysis is processed using this data that the data be discussed with a resource specialist in the particular field. The Forest Service reserves the right to correct, update, modify, or replace, GIS products without notification. For more information, contact the Clearwater National Forest Supervisor's Office, Orofino, Idaho, 1-208-476-4541</PRE></SPAN><BR /> <SCRIPT>fix(original)</SCRIPT> </DIV> </DIV> </DIV> </DIV> </DIV> <BR /> <DIV CLASS="ph1" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Details about this document <DIV CLASS="pe2" STYLE="display:none"> Contents last updated: 20080110 at time 13054800 <DIV CLASS="ph1" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Who completed this document <DIV CLASS="pe2" STYLE="display:none"> USDA Forest Service - Clearwater National Forest<BR /><I>mailing address:</I><BR /><DIV STYLE="margin-left:0.3in"> <DIV CLASS="lt"> <PRE ID="original">12730 Hwy 12</PRE> <SCRIPT>fix(original)</SCRIPT> </DIV> <DIV> Orofino, ID 83544</DIV> <DIV>USA</DIV></DIV> <BR /> 208-476-4541 (voice)<BR /><BR /> </DIV> </DIV> <DIV CLASS="ph1" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Standards used to create this document <DIV CLASS="pe2" STYLE="display:none"> <I>Standard name: </I>FGDC Content Standards for Digital Geospatial Metadata<BR /> <I>Standard version: </I>FGDC-STD-001-1998<BR /> <I>Time convention used in this document: </I>local time<BR /> Metadata profiles defining additonal information<LI STYLE="margin-left:0.2in"> ESRI Metadata Profile: <A TARGET="viewer" HREF="http://www.esri.com/metadata/esriprof80.html">http://www.esri.com/metadata/esriprof80.html </A> </LI> <LI STYLE="margin-left:0.2in"> ESRI Metadata Profile: <A TARGET="viewer" HREF="http://www.esri.com/metadata/esriprof80.html">http://www.esri.com/metadata/esriprof80.html </A> </LI> <LI STYLE="margin-left:0.2in"> ESRI Metadata Profile: <A TARGET="viewer" HREF="http://www.esri.com/metadata/esriprof80.html">http://www.esri.com/metadata/esriprof80.html </A> </LI> </DIV> </DIV> </DIV> </DIV> <BR /> </DIV> <DIV ID="Spatial" class="pv" STYLE="display:none"><BR /> <DIV CLASS="pn">Horizontal coordinate system</DIV> <DIV STYLE="margin-left:0.2in"><I>Projected coordinate system name: </I>NAD_1983_UTM_Zone_11N</DIV> <DIV STYLE="margin-left:0.2in"><I>Geographic coordinate system name: </I>GCS_North_American_1983</DIV> <DIV CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Details <DIV CLASS="pe2" STYLE="display:none"> <DIV CLASS="sr1"><SPAN CLASS="pn">Grid Coordinate System Name: </SPAN>Universal Transverse Mercator</DIV> <DIV CLASS="sr2"><I>UTM Zone Number: </I>11</DIV> <DIV CLASS="srh2">Transverse Mercator Projection</DIV> <DIV CLASS="sr3"><I>Scale Factor at Central Meridian: </I>0.999600<BR /> <I>Longitude of Central Meridian: </I>-117.000000<BR /> <I>Latitude of Projection Origin: </I>0.000000<BR /> <I>False Easting: </I>500000.000000<BR /> <I>False Northing: </I>0.000000<BR /> </DIV> <BR /> <DIV CLASS="sr1"><SPAN CLASS="pn">Planar Coordinate Information</SPAN></DIV> <DIV CLASS="sr2"><I>Planar Distance Units: </I>meters</DIV> <DIV CLASS="sr2"><I>Coordinate Encoding Method: </I>coordinate pair</DIV> <DIV CLASS="srh2">Coordinate Representation</DIV> <DIV CLASS="sr3"><I>Abscissa Resolution: </I>0.000064</DIV> <DIV CLASS="sr3"><I>Ordinate Resolution: </I>0.000064</DIV> <BR /> <DIV CLASS="srh1">Geodetic Model</DIV> <DIV CLASS="sr2"><I>Horizontal Datum Name: </I>North American Datum of 1983</DIV> <DIV CLASS="sr2"><I>Ellipsoid Name: </I>Geodetic Reference System 80</DIV> <DIV CLASS="sr2"><I>Semi-major Axis: </I>6378137.000000</DIV> <DIV CLASS="sr2"><I>Denominator of Flattening Ratio: </I>298.257222</DIV> </DIV> </DIV> <BR /> <DIV CLASS="srh1">Altitude System Definition</DIV> <DIV CLASS="sr2"><I>Resolution: </I>1.000000</DIV> <DIV CLASS="sr2"><I>Encoding Method: </I>Explicit elevation coordinate included with horizontal coordinates</DIV> <DIV STYLE="text-align:center; color:#6495ED">_________________</DIV><BR /> <DIV CLASS="pn">Bounding coordinates</DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn">Horizontal</DIV> <DIV STYLE="margin-left:0.4in" CLASS="pn">In decimal degrees</DIV> <DIV STYLE="margin-left:0.6in"><I>West: </I> -115.801412</DIV> <DIV STYLE="margin-left:0.6in"><I>East: </I> -114.302321</DIV> <DIV STYLE="margin-left:0.6in"><I>North: </I> 47.024262</DIV> <DIV STYLE="margin-left:0.6in"><I>South: </I> 46.099707</DIV> <DIV STYLE="margin-left:0.4in" CLASS="pn">In projected or local coordinates</DIV> <DIV STYLE="margin-left:0.6in"><I>Left: </I>592601.248866</DIV> <DIV STYLE="margin-left:0.6in"><I>Right: </I>705091.412938</DIV> <DIV STYLE="margin-left:0.6in"><I>Top: </I>5208580.826875</DIV> <DIV STYLE="margin-left:0.6in"><I>Bottom: </I>5108548.852126</DIV> <DIV STYLE="text-align:center; color:#6495ED">_________________</DIV><BR /> <DIV CLASS="pn">Lineage</DIV> <DIV CLASS="pn" STYLE="margin-left:0.2in">FGDC lineage</DIV> <DIV CLASS="ph2" STYLE="margin-left:0.4in" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">Process step 1 <DIV CLASS="pe2" STYLE="margin-left:0.2in; display:none"> <I>Process description: </I>combination of rock polygons from the Idaho Geological Survey, University of Idaho the following 30 x 60 minute quadrangles: Kooskia Hamilton Missoula West Headquarters data tables for the 4 coverages are combined in this feature class.<BR /> <I>Process date: </I>1/10/2008 <BR /> </DIV> </DIV> <DIV STYLE="text-align:center; color:#6495ED">_________________</DIV><BR /> <DIV CLASS="pn">Spatial data description</DIV> <DIV CLASS="pn" STYLE="margin-left:0.2in">Vector data information</DIV> <DIV STYLE="margin-left:0.4in" CLASS="pn">ESRI description</DIV> <DIV CLASS="ph2" STYLE="margin-left:0.6in" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> rocks_east <DIV CLASS="pe2" STYLE="display:none"> <I>ESRI feature type: </I>Simple<BR /> <I>Geometry type: </I>Polygon<BR /> <I>Topology: </I>FALSE<BR /> <I>Feature count: </I>70<BR /> <I>Spatial Index: </I>TRUE<BR /> <I>Linear referencing: </I>FALSE<BR /> </DIV> </DIV> <BR /> <DIV CLASS="ph2" STYLE="margin-left:0.4in" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)">SDTS description <DIV CLASS="pe2" STYLE="display:none"> <DIV>Feature class: SDTS feature type, feature count</DIV> <DIV STYLE="margin-left:0.2in"> <LI> rocks_east: G-polygon, 70 </LI> </DIV> <DIV STYLE="margin-left:0.2in"> <LI> Feature class: Label point, 22 </LI> </DIV> <DIV STYLE="margin-left:0.2in"> <LI> Feature class: GT-polygon composed of chains, 22 </LI> </DIV> <DIV STYLE="margin-left:0.2in"> <LI> Feature class: Point, 947 </LI> </DIV> </DIV> </DIV> <BR /> </DIV> <DIV ID="Attributes" class="pv" STYLE="display:none"><BR /> <DIV CLASS="pn">Details for rocks_east</DIV> <DIV STYLE="margin-left:0.2in"><I>Type of object: </I>Feature Class</DIV> <DIV STYLE="margin-left:0.2in"><I>Number of records: </I>70</DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> Attributes<DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> OBJECTID <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>OBJECTID<BR /> <I>Data type: </I>OID<BR /> <I>Width: </I>4<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <SPAN CLASS="lt"><I>Definition: </I><PRE ID="original">Internal feature number.</PRE></SPAN> <SCRIPT>fix(original)</SCRIPT> <SPAN CLASS="lt"><I>Definition Source: </I><PRE ID="original">ESRI</PRE></SPAN> <SCRIPT>fix(original)</SCRIPT> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> Shape <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>Shape<BR /> <I>Data type: </I>Geometry<BR /> <I>Width: </I>0<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <SPAN CLASS="lt"><I>Definition: </I><PRE ID="original">Feature geometry.</PRE></SPAN> <SCRIPT>fix(original)</SCRIPT> <SPAN CLASS="lt"><I>Definition Source: </I><PRE ID="original">ESRI</PRE></SPAN> <SCRIPT>fix(original)</SCRIPT> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> VALUE <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>VALUE<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>10<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> VALUE_GROUP <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>VALUE_GROUP<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>12<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> ROCKNAME <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>ROCKNAME<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>100<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> MAP_ID1 <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>MAP_ID1<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>14<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> STRATORDER <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>STRATORDER<BR /> <I>Data type: </I>Integer<BR /> <I>Width: </I>4<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> DESCRIBE <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>DESCRIBE<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>254<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> DESCRIBE_2 <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>DESCRIBE_2<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>254<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> DESCRIBE_3 <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>DESCRIBE_3<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>254<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> TEXTURE <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>TEXTURE<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>100<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> MINERALS <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>MINERALS<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>150<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> GROUP <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>GROUP<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>50<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> FORMATION <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>FORMATION<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>50<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> MEMBER <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>MEMBER<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>50<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> TIMEUNIT <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>TIMEUNIT<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>40<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> AGE <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>AGE<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>12<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> DATING <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>DATING<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>100<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> THICKNESS <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>THICKNESS<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>15<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> SOURCE <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>SOURCE<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>150<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> CONFORM_ON <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>CONFORM_ON<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>15<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> UNCONFM_ON <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>UNCONFM_ON<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>15<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> POLARITY <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>POLARITY<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>4<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> REL_DATING <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>REL_DATING<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>60<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> FOSSILS <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>FOSSILS<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>100<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> PED_CLAY <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>PED_CLAY<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>25<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> DURIPANS <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>DURIPANS<BR /> <I>Data type: </I>String<BR /> <I>Width: </I>25<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> Shape_Length <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>Shape_Length<BR /> <I>Data type: </I>Double<BR /> <I>Width: </I>8<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <SPAN CLASS="lt"><I>Definition: </I><PRE ID="original">Length of feature in internal units.</PRE></SPAN> <SCRIPT>fix(original)</SCRIPT> <SPAN CLASS="lt"><I>Definition Source: </I><PRE ID="original">ESRI</PRE></SPAN> <SCRIPT>fix(original)</SCRIPT> <BR /> </DIV> </DIV> </DIV> <DIV STYLE="margin-left:0.2in" CLASS="pn"> <DIV STYLE="margin-left:0.25in" CLASS="ph2" onmouseover="doHilite()" onmouseout="doHilite()" onclick="hideShowGroup(this)"> Shape_Area <DIV CLASS="pe2" STYLE="display:none"> <I>Alias: </I>Shape_Area<BR /> <I>Data type: </I>Double<BR /> <I>Width: </I>8<BR /> <I>Precision: </I>0<BR /> <I>Scale: </I>0<BR /> <SPAN CLASS="lt"><I>Definition: </I><PRE ID="original">Area of feature in internal units squared.</PRE></SPAN> <SCRIPT>fix(original)</SCRIPT> <SPAN CLASS="lt"><I>Definition Source: </I><PRE ID="original">ESRI</PRE></SPAN> <SCRIPT>fix(original)</SCRIPT> <BR /> </DIV> </DIV> </DIV> <BR /> </DIV> </DIV> </BODY> </HTML>