GENERALIZED SURFICIAL GEOLOGIC MAP OF THE PUEBLO 1˚ x 2˚ QUADRANGLE, COLORADO Compiled by David W. Moore, Arthur W. Straub, Margaret E. Berry, Michael L. Baker, and Theodore R. Brandt 2002 MISCELLANEOUS FIELD STUDIES MAP MF-2388 Version 1.0 Pamphlet accompanies map Base from U.S. Geological Survey, 1989 Transverse Mercator Projection 100 000-foot grid ticks based on Colorado coordinate system, central and south zones Gray numbered lines indicate the 100,000-meter Universal Transverse Mercator grid, zone 13 Compiled during 1997-1999 D.W. Moore, Coordinator Digital Cartography by T.R. Brandt and M.L. Baker Manuscript approved for publication April 30, 2002 U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY f s pga afk afa es ed elb cac cbv ccd ccm clo csk cgg cgh cgc cbh cbm cbs cbu cbw cra xch xci xlh xlj xlu xsg R Holocene late Pleistocene middle Pleistocene early Pleistocene MAN-MADE DEPOSITS ALLUVIAL DEPOSITS EOLIAN DEPOSITS COLLUVIAL DEPOSITS DISINTEGRATION RESIDUUM BEDROCK jbg ? ? dbd dbc dba CORRELATION OF MAP UNITS tbg tbj tbk tbi wla esa oc LAKE DEPOSIT clx csm jea jba jbc LANDSLIDE DEPOSITS COLLUVIUM, ALLUVIUM, AND ROCK OUTCROP cck cby ags ? agm asa afb QUATERNARY PRE-QUATERNARY GLACIAL AND PERIGLACIAL DISINTEGRATED DEPOSITS AND ROCK OUTCROP gge ggq f Artificial landfill Slag s afa Alluvial-fan deposit cac Arkosic loamy colluvium and sheetwash alluvium cbv Metamorphic and metavolcanic blocky colluvium xch Clayey, calcareous disintegration residuum HOLOCENE HOLOCENE AND LATE PLEISTOCENE dba Disintegrated deposits, periglacial deposits, bouldery till, and rock outcrop Crystalline-clast deposits Sedimentary-clast deposits dbc dbd Mixed-lithology-clast deposits asa Alluvial sand, silt, clay, and gravel (post-Piney Creek alluvium, Piney Creek Alluvium, and pre-Piney Creek alluvium of Hunt, 1954, and Scott, 1960; Broadway Alluvium) es Eolian sand ed Stabilized dune sand jea Slump-block landslide deposits, earthflow and mudflow deposits ccd Calcareous clayey colluvium cck Tuff-clast loam and clay loam colluvium csm Tuffaceous colluvium csk Grus, crystalline-clast colluvium, alluvium, and rock outcrop cgg Sandstone-clast sandy loam to clay loam colluvium cgh Arkosic-clast loamy colluvium cgc Gneiss- and granite-clast gravelly colluvium cbh Blocky sedimentary-rock colluvium cbm Carbonate-clast loamy colluvium cbs Rhyolite- and andesite-clast colluvium cbu Mixed-lithology blocky colluvium cbw Blocky basalt- and andesite-clast colluvium Sandy clay disintegration residuum xci Limestone-chip loamy disintegration residuum xlh xlu Feldspathic loamy disintegration residuum HOLOCENE TO MIDDLE PLEISTOCENE Bouldery volcanic-rock landslide deposit jba Bouldery crystalline-rock landslide deposit jbc Feldspathic quartz-sand disintegration residuum xsg elb LATE PLEISTOCENE Loess (Peoria Formation) LATE AND MIDDLE PLEISTOCENE tbg Crystalline-clast bouldery till tbi Sedimentary-clast bouldery till tbj Mixed-lithology-clast bouldery till ggq Outwash sand and gravel (of Bull Lake, Pinedale, and post-Pinedale ages) ags Alluvial sand, silt, clay, and gravel (Louviers and Slocum Alluviums, undivided; late middle Pleistocene) afb Alluvial-fan gravelly loam tbk MIDDLE AND EARLY PLEISTOCENE Bouldery till (of pre-Bull Lake glaciations) gge Outwash sand and gravel (of pre-Bull Lake glaciations) agm Alluvial gravel and sand (Verdos and Rocky Flats Alluviums, undivided; early middle Pleistocene and early Pleistocene) afk Alluvial-fan gravelly loam Loamy or clayey sheetwash alluvium wla Playa clay Eolian sheet sand and loess (included in the "cover sand" of Frye and Leonard, 1957, and Blackwater Draw Formation of Reeves, 1976, described by Holiday, 1989) oc esa Andesitic clayey colluvium Clay loam colluvium clx ccm [For map unit descriptions and references see "Description of Map Units" in accompanying pamphlet] LIST OF MAP UNITS Bouldery till (of Pinedale and Bull Lake glaciations) Blocky feldspathic-sandstone colluvium Silty loam disintegration residuum Shale-, chalk-, and chalky-limestone-clast loamy colluvium cby xlj clo Any use of trade names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government For sale by U.S. Geological Survey Information Services, Box 25286, Federal Center, Denver, CO 80225 This map was produced on request, directly from digital files, on an electronic plotter. It is also available as a PDF file at http://geology.cr.usgs.gov QUATERNARY cra Hogback and rangefront colluvium, alluvium, and rock outcrop pga Pediment gravel PLEISTOCENE jbg Granodiorite-block debris-avalanche deposit PRE-QUATERNARY R Bedrock Open Water Fault, Quaternary age—Bar and ball on downthrown side w High-angle reverse fault—Inferred, R on upthrown block R Contact cbh asa cbh cgc ags cck cbh agm ags cck csk csk cbh cck cbu cbm csk cbh csm cbv agm tbg tbj csm ggq cbh afk afk cbh dbd tbj afb csk csk ed csk dbc cbh afb dbc tbi tbi cgc cbm pga ggq csk afb pga ggq w cgc tbi tbk dbc tbi agm cgc cgc cbs afb afb jba jba asa cgc ags agm jea jea cgg xsg ags agm ags agm cby agm ags asa jbc agm cbs ags jea ags asa ags cgh afa ags asa jea xsg tbg cgh agm cgc jbc ags xlu xlu cac xch agm elb xch agm elb agm ags xch agm xch xci asa xci esa xlj ags agm ccd agm ags cac asa cac xch agm asa ags agm cbu xci cbh csk csk cgc agm asa asa cgh asa asa asa cac jba cbw cbh cbm csm cgc afb afb ggq ggq csk csk asa asa xci clo xlh asa asa xch ags xch asa xci xci xci asa ags xsg xsg csk csk agm cbm agm agm ags ags ags ags asa xch ags ags ags jbg afa agm agm ags asa agm agm asa xsg xsg agm asa ags ags asa asa afa csk jba ags w xch asa jea afa jbc agm asa f s cra cgg cbm ggq csk dbd tbj dbc dbc dbc cbh cbh asa cbw ags csk jea asa jea jea cbh cra cgh cbm cgg ags cbm jbc jbc xci ccd xlh cgg cbm ags cck afk afk dbc tbj ggq cbv cgc cgc cgc cbs cbs cbs cgc cck dba agm cck ags jba cbh gge cgg cgh xch xch xci agm xlu jea w asa asa asa jea ggq ggq cac cgg xch cgg cgg cbs cbs ags asa cra w cbu ags ags csm cbm cbs cgc cck cbs cbm cbm cck jba f w f w csk csk cbh ags ags cbu cbs cbs cbh cbu cbu jbc cgg cgg xch cbu csk cbs jba ggq ags gge ggq jbc tbg cbs csm cbm cbu cbm cbm xsg csk csk csk afa jba tbg agm wla xch xch xlh ags xlj clo xci xlh xlj xlh xlh xlh clo xlh w es es es es es es es es es es es es es es es es es es es es w w oc oc oc oc oc xch w oc afa ccd xch oc asa xch cac clx ccm cac clx agm agm ccd es xch cgg ccd ccd ccd ccd ccd xch xch ggq R R R R R dbd R R tbj cra R R R ags cbu ccd agm jea R R R R R R R R R R R R R R R jea jea R ags tbj w agm ags cgc cbs ags agm R R 5 5 0 10 15 20 25 KILOMETERS 10 5 0 5 15 20 MILES CONTOUR INTERVAL 100 METERS SUPPLEMENTARY CONTOUR INTERVAL 50 METERS 1989 MAGNETIC DECLINATION FROM THE NORTH VARIES FROM 11.5ß (204 MILS) EASTERLY FOR THE CENTER OF THE WEST EDGE TO 10.5ß (187 MILS) EASTERLY FOR THE CENTER OF THE EAST EDGE. MEAN ANNUAL CHANGE IS 4.9’ WESTERLY SCALE 1:250 000 ARIZONA NEW MEXICO UTAH STERLING I-1092 LAMAR I-944 LA JUNTA I-560 TRINIDAD I-558 SALINA I-591 SHIPROCK I-345 GALLUP I-981 ESCALANTE I-744 CORTEZ I-629 MOAB I-360 GRAND JUNCTION I-736 MONTROSE MF-761 DURANGO I-764 LEADVILLE I-999 COLORADO RIVER PHOENIX SALT LAKE CITY SANTA FE PUEBLO I-1022 ARKANSAS RIVER RIO GRANDE GREEN RIVER CRAIG I-972 LIMON I-1250 MF-2347 I-1163 DENVER COLORADO AZTEC I-1730 MARBLE CANYON I-1003 FLAGSTAFF I-1446 GREELEY OF 78-532 VERNAL I-1526 RICHFIELD I-1901 PRICE I-2462 SALT LAKE CITY I-1997 116˚ 114˚ 112˚ 110 ˚ 108˚ 106˚ 104˚ 102˚ 42˚ 40˚ 38˚ 36˚ 34˚ 32˚ 0 100 200 MILES 0 100 200 KILOMETERS INDEX MAP SHOWING AREA OF PUEBLO QUADRANGLE, COMPANION GENERALIZED SURFICIAL GEOLOGIC MAP OF THE DENVER QUADRANGLE (shown in gray), AND OTHER PUBLISHED 1˚ x 2˚ GEOLOGIC MAPS