Identification_Information: Citation: Citation_Information: Originator: Karl S. Kellogg Originator: Chester A. Ruleman Originator: Ralph R. Shroba Publication_Date: 2010 Title: Geologic Map of the Clark Peak Quadrangle, Jackson and Larimer Counties, Colorado Edition: Version 2.0 Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Scientific Investigations Map (SIM) Issue_Identification: 3010 Publication_Information: Publication_Place: Denver, Colorado Publisher: U.S. Geological Survey Online_Linkage: http://pubs.usgs.gov/sim/3010 Description: Abstract: The Clark Peak quadrangle encompasses the southern end of the Medicine Bow Mountains and the northernmost end of the Mummy Range. The Continental Divide traverses the map area and Highway 14 cross the Divide at Cameron Pass, in the southeastern corner of the map. Approximately the eastern half of the map, and a few areas to the west, are underlain by Early Proterozoic plutonic and metamorphic rocks. Most of these basement rocks are part of the ~1,715 Ma Rawah batholith, composed mostly of pinkish, massive to moderately foliated monzogranite and granodiorite intruded by numerous, large pegmatite- aplite bodies. The metamorphic rocks, many of which form large inclusions in the granitic rocks of the Rawah batholith, include biotite-hornblende gneiss, hornblende gneiss, amphibolite, and biotite schist. The crystalline basement rocks are thrust westward along the Medicine Bow thrust over a sequence of sedimentary rocks as old as the Upper Permian Satanka Shale. The Satanka Shale, Middle and Lower Triassic Chugwater Group, and a thin sandstone tentatively correlated with the Lower Jurassic and Upper Triassic Jelm Formation are combined as one map unit. This undivided unit is overlain sequentially upward by the Upper Jurassic Sundance Formation, Upper Jurassic Morrison Formation, Lower Cretaceous Dakota Group, Upper and Lower Cretaceous Benton Group, Upper Cretaceous Niobrara Formation, and the Eocene and Paleocene Coalmont Formation. The Late Cretaceous to early Eocene Medicine Bow thrust is folded in places, and along with several back thrusts produced a complicated thrust pattern in the south part of the map. In addition, several late Eocene and younger, north-striking normal faults are contemporaneous with a widespread period of crustal extension. Early Oligocene magmatism produced rhyolite tuff, dacite and basalt flows, and intermediate dikes and small stocks. A 40Ar/39Ar date on sanidine from one rhyolite tuff is ~28.5 Ma; a similar whole-rock date on a trachybasalt is ~29.6 Ma. A very coarse, unsorted probably pre-Quaternary ridge-top diamicton crops out in the southern part of the quadrangle. Numerous glacial deposits (mostly of Pinedale age), rock glaciers, block-slope deposits, landslide deposits, talus deposits, fan deposits, colluvium, and alluvium comprise the surficial deposits of the map area. Purpose: To provide geologic information (including rock descriptions, geologic structures, surficial deposits, and geologic hazards) for and important area studied during completion of the USGS Central Colorado Assessment Project Supplemental_Information: Datasets included in the publication: CLARKPEAK.GDB (geodatabase) CLARKPEAK.SHP (shapefile) features: clarkpeak_geo_poly: polygon area features of geologic rock units clarkpeak_geo_label: point labels containing polygon attributes clarkpeak_geo_line: linear features(contacts, faults etc.) clarkpeak_geo_fld: linear features showing folds clarkpeak_geo_pnt: point features(bedding, foliation etc.) Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2010 Currentness_Reference: publication date Status: Progress: complete Maintenance_and_Update_Frequency: none planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -106.00 East_Bounding_Coordinate: -105.875 North_Bounding_Coordinate: 40.625 South_Bounding_Coordinate: 40.50 Keywords: Theme: Theme_Keyword_Thesaurus: American Geological Institute Glossary of Geology Theme_Keyword: Geology Theme_Keyword: geologic map Theme_Keyword: surficial geology Theme_Keyword: glacial geology Theme_Keyword: bedrock geology Theme_Keyword: Proterozoic rocks Theme_Keyword: Mesozoic rocks Place: Place_Keyword_Thesaurus: U.S. Board of Geographic Names Place_Keyword: Cameron Pass Place_Keyword: Cameron Peak Place_Keyword: Clark Peak Place_Keyword: Medicine Bow Mountains Place_Keyword: Michigan River Place_Keyword: North Fork Michigan River Place_Keyword: Never Summer Mountains Access_Constraints: none Use_Constraints: Users of this geospatial database and geologic information derived there from should acknowledge the U.S. Geological Survey as the source data. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Karl Kellogg Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing address Address: MS 980, Box 25046 Denver Federal Center City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: 303-236-1305 Contact_Facsimile_Telephone: 303-236-5349 Contact_Electronic_Mail_Address: kkellogg@usgs.gov Data_Set_Credit: Thanks to Chris Fridrich and Jeremy Workman (reviewers) and Darren(Paco) VanSistine (GIS specialist). Native_Data_Set_Environment: Windows_NT, 5.1, Intel ArcInfo version 9.2 Browse_Graphic: Browse_Graphic_File_Name: http://pubs.usgs.gov/sim/3010 Browse_Graphic_File_Description: graphic representation of map Browse_Graphic_File_Type: PDF Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Data were entered and checked by the geologists who made the field observations and compilation. The attributes of this geospatial data set consist of text identifiers and numeric codes that indicate the identity of the geologic unit or type of geologic feature, and determine how each feature is colored or symbolized. To check the attribute accuracy, a color check plot was visually compared to the geologists' original compilation. Discrepancies between the digital geospatial data set and the original analog compilation were corrected as needed. Machine-created listings of unique attribute values were used to identify spelling errors or other inconsistencies, and corrections were made as needed. This map has been thoroughly reviewed for conformity with U.S. Geological Survey editorial standards and stratigraphic nomenclature. Logical_Consistency_Report: Map elements were visually checked for overshoots, undershoots, duplicate features, polygon closure, and other errors by the authors and by the GIS technician(s) who created the digital database. Automated (ArcInfo) routines were also used to check the databases for polygon label errors, line or point attribution errors, sliver polygons, dangling arcs, intersection errors, and projection information. Check plots of the map were reviewed by another geologist and cartographer for consistency with basic geologic principles and general conformity to USGS mapping standards. Completeness_Report: No features that could be accurately represented at a scale of 1:24,000 were eliminated or generalized. All geospatial database elements are attributed. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Horizontal accuracy on the ground is believed to be within 20 meters. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Braddock, W.A. Originator: Cole, J.C. Title: Geologic map of Rocky Mountain National Park and vicinity, Colorado Publication_Date: 1990 Series_Information: Series_Name: U.S. Geological Survey Map Issue_Identification: I-1973 Source_Scale_Denominator: 50000 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1990 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Braddock and Cole (1990) Source_Contribution: map feature information Source_Information: Source_Citation: Citation_Information: Originator: Corbett, M.K. Title: Tertiary volcanism of the Specimen-Lulu-Iron Mountain area, north-central Colorado Publication_Date: 1968 Series_Information: Series_Name: Colorado School of Mines Quarterly Issue_Identification: v. 63 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1968 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Corbett (1968) Source_Contribution: map feature information Source_Information: Source_Citation: Citation_Information: Originator: Gorton, K.A. Title: Geology of the Cameron Pass area, Grand, Jackson, and Larimer Counties, Colorado Publication_Date: 1953 Series_Information: Series_Name: Wyoming Geological Association Guidebook Issue_Identification: 8th Annual Field Conference Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1953 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Gorton (1953) Source_Contribution: map feature information Source_Information: Source_Citation: Citation_Information: Originator: Griswold, M.L. Title: Petrology and structure of the southwestern portion of the Precambrian Rawah batholith, Medicine Bow Mountains, north-central Colorado Publication_Date: 1980 Series_Information: Series_Name: M.S. thesis, Colorado State University Issue_Identification: unknown Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1980 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Griswold (1980) Source_Contribution: map feature information Source_Information: Source_Citation: Citation_Information: Originator: Knox, Katherine Title: A petrographic and geochronologic study of volcanic rocks of the northern Never Summer Range, Colorado Publication_Date: 2006 Series_Information: Series_Name: University of Colorado M.S. Thesis Issue_Identification: unknown Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2006 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Knox (2006) Source_Contribution: map feature information Source_Information: Source_Citation: Citation_Information: Originator: O’Neill, J.M. Title: Geologic map of the Mount Richthofen quadrangle and the western part of the Fall River Pass quadrangle, Grand and Jackson Counties, Colorado Publication_Date: 1981 Series_Information: Series_Name: U.S. Geological Survey Miscellaneous Investigations Series Map Issue_Identification: I-1291 Source_Scale_Denominator: 24000 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1981 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: O’Neill (1981) Source_Contribution: map feature information Source_Information: Source_Citation: Citation_Information: Originator: Pearson, R.C. Originator: McCallum, M.E. Originator: Griswold, M.L. Originator: Patten, L.L. Title: Mineral resources of the Rawah Wilderness, Larimer, County, Colorado Publication_Date: 1982 Series_Information: Series_Name: U.S. Geological Survey Open-File Report Issue_Identification: 82-376 Source_Scale_Denominator: 24000 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1982 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Pearson and others (1982) Source_Contribution: map feature information Process_Step: Process_Description: Original GIS information captured using Adobe Illustrator CS2, with MapPublisher 7 as an add-on. Data then transferred to ArcInfo for final compilation. Process_Date: 2007 Process_Step: Process_Description: Checkplots of the data were printed and checked against source materials for accuracy and completeness. The database information was checked visually, as well as by using various routines in ArcInfo, for accuracy and consistency. Process_Date: 2007 Process_Step: Process_Description: First draft of metadata created by Paco VanSistine Process_Date: 2007 Process_Step: Process_Description: Version 2.0 updates to geologic map and dataset made in ArcGIS. Process_Date: 2010 Process_Step: Process_Description: Second draft of metadata created by Paco VanSistine Process_Date: 2010 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 13 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.9996 Longitude_of_Central_Meridian: -105.0 Latitude_of_Projection_Origin: 0.0 False_Easting: 500000 False_Northing: 0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: 0.0001 Ordinate_Resolution: 0.0001 Planar_Distance_Units: Meters Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1927 Ellipsoid_Name: Clarke 1866 Semi-major_Axis: 6378206.4 Denominator_of_Flattening_Ratio: 294.98 Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: CLARKPEAK.GDB Feature Classes in the GEOLOGY Feature Dataset: CLARKPEAK_GEO_POLY: UNIT - GEOLOGIC UNIT LABEL DESCRIPTION - BRIEF GEOLOGIC UNIT DESCRIPTION AGE - GEOLOGIC AGE OF ROCK UNIT UNIT DESCRIPTION Breccia Breccia zone Tertiary? Jm Morrison Formation Upper Jurassic Jms Morrison Formation and Sundance Formation, undivided Upper Jurassic Js Sundance Formation Upper Jurassic Kb Benton Shale Upper and Lower Cretaceous Kd Dakota Sandstone Lower Cretaceous Kn Niobrara Formation Upper Cretaceous QTd Diamicton lower? Pleistocene to Miocene? Qa Alluvium Holocene and late Pleistocene Qac Alluvium and colluvium, undivided Holocene to middle? Pleistocene Qbs Block-slope deposit Holocene to late Pleistocene Qc Colluvium Holocene to middle? Pleistocene Qf Fan deposit Holocene and late Pleistocene Qgb Outwash gravel of Bull Lake glaciation late and middle Pleistocene Qgp Outwash gravel of Pinedale glaciation late Pleistocene Qls Landslide deposit Holocene to middle? Pleistocene Qr Rock-glacier deposit Holocene and late Pleistocene Qt Talus deposit Holocene to middle? Pleistocene Qtp Till of Pinedale age late Pleistocene Ta Andesite flow lower Oligocene Tab Aphanitic alkalic basalt lower Oligocene Tc Coalmont Formation Eocene and Paleocene Tdc Dacite Oligocene Ti Intrusive porphyry Oligocene? Tr Rhyolite Oligocene TrPc Jelm? Formation, Chugwater Formation, Forelle Limestone, and Satanka Shale, undivided Upper Triassic to Lower Permian Tv Volcanic rocks, undivided Oligocene Xbh Biotite-hornblende gneiss Early Proterozoic Xgg Granitic gneiss Early Proterozoic Xgr Granitic rocks of the Rawah batholith Early Proterozoic Xhg Hornblende-plagioclase gneiss and amphibolite Early Proterozoic Xs Biotite-muscovite schist and gneiss Early Proterozoic Xsbc Sillimanite-biotite-cordierite gneiss Early Proterozoic YXp Pegmatite and aplite Middle Proterozoic and Early Proterozoic YXum Metapyroxenite MIddle Proterozoic or Early Proterozoic af Artificial fill latest Holocene water Water body CLARKPEAK_GEO_LINE: DESCRIPTION - LINE FEATURE EXPLANATION USING DIGITAL CARTOGRAPHIC STANDARDS DESCRIPTION Contact-Certain Contact-Concealed Diabase dike Fault-Certain Fault-Concealed Intrusive porphyry Normal fault-Certain Normal fault-Concealed Shorline Thrust fault-Certain Thrust fault-Concealed CLARKPEAK_GEO_FLD: DESCRIPTION - FOLD LINE FEATURE EXPLANATION USING DIGITAL CARTOGRAPHIC STANDARDS DESCRIPTION Anticline-Certain Anticline-Concealed Overturned syncline-Concealed Syncline-Certain Syncline-Concealed CLARKPEAK_GEO_PNT: AZIMUTH - DIRECTION ANGLE OF PLANER FEATURE(0 - 359 degrees) DIP - ANGLE FROM WHICH PLANER FEATURE DEVIATES FROM HORIZONTAL - MEASURED PERPENDICULAR TO STRIKE/AZIMUTH(0 - 90 degrees) DESCRIPTION - POINT FEATURE EXPLANATION USING DIGITAL CARTOGRAPHIC STANDARDS DESCRIPTION cleavage in shale-showing strike and dip, may be parallel to bedding fault dip inclined bedding-showing strike and dip inclined foliation-showing strike and dip overturned bedding-showing strike and dip vertical bedding-showing strike vertical or near-vertical foliation-showing strike Entity_and_Attribute_Detail_Citation: none Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing address Address: Publishing Service Center City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: 1-888-ASK-USGS Contact_Instructions: Contact via email Contact_Electronic_Mail_Address: webmaster@geology.cr.usgs.gov Distribution_Liability: none. This database, identified as SIM-3010, has been approved for release and publication by the Director of the USGS. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: ARCE, SHP Format_Version_Number: 9.2 File_Decompression_Technique: GZIP compressed TAR file ZIP archive Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://pubs.usgs.gov/sim/3010 Fees: none Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Voice_Telephone: 1-888-ASK-USGS Contact_Address: Address_Type: mailing address Address: USGS Information Services Box 25286 City: Denver State_or_Province: CO Postal_Code: 80225 Country: United States Resource_Description: USGS Scientific Investigations Map (SIM) Distribution_Liability: Any use of trade, product or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Geological Survey. Although this information product, for the most part, is in the public domain, it also contains copyrighted materials as noted in the text. Permission to reproduce copyrighted items for other than personal use must be secured from the copyright owner. Standard_Order_Process: Non-digital_Form: Available as one printed sheet plus one pamphlet. Order from USGS at the address listed above or see http://rmmcweb.cr.usgs.gov/public/mod/order.html for more ordering information. Fees: for current charges please see http://rmmcweb.cr.usgs.gov/public/mod/order.html Metadata_Reference_Information: Metadata_Date: 2010 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Paco VanSistine Contact_Address: Address_Type: mailing address Address: U.S. Geological Survey MS 980, Box 25046 Denver Federal Center City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: 303-236-5452 Contact_Electronic_Mail_Address: dvansistine@usgs.gov Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata ("CSDGM version 2") Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Access_Constraints: none Metadata_Use_Constraints: none