Identification_Information: Citation: Citation_Information: Originator: Ren A. Thompson Originator: Ralph R. Shroba Originator: Michael N. Machette Originator: Christopher J. Fridrich Originator: Theodore R. Brandt Originator: Michael A. Cosca Publication_Date: 2015 Title: Geologic map of the Alamosa 30’ x 60’ quadrangle, South-Central Colorado Edition: 1.0 Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: USGS Scientific Investigations Map Issue_Identification: SIM 3342 Publication_Information: Publication_Place: Denver, Colorado Publisher: U.S. Geological Survey Online_Linkage: http://dx.doi.org/10.3133/sim3342 Description: Abstract: The Alamosa 30’ x 60’quadrangle is located in the central San Luis Basin of southern Colorado and is bisected by the Rio Grande having headwaters in the San Juan Mountains of Colorado and ultimately discharging into the Gulf of Mexico > 3000 km downstream. Alluvial floodplains and associated deposits of the Rio Grande and east-draining tributaries, La Jara Creek and Conejos River, occupy the north central and northwestern part of the map area. Alluvial deposits of west- draining Rio Grande tributaries, Culebra and Costilla creeks, bound the Costilla Plain in the south central part of the map area. The San Luis Hills, a northeast trending series of flat-topped mesas and hills, dominate the landscape in the central and southwestern part of the map and preserve fault-bound Neogene basin surfaces and deposits. The Precambrian-cored Sangre de Cristo Mountains rise to an elevation of nearly 4300 meters, almost 2000 meters above the valley floor, in the eastern part of the map area. In total, the map area contains deposits that record surficial, tectonic, sedimentary, volcanic, magmatic and metamorphic processes over the past 1.7 billion years. The mapped distribution of units is based primarily on interpretation of U.S. Geological Survey (USGS) 1:40,000-scale, black-and-white, aerial photographs; U.S. Department of Agriculture (http://www.fsa.usda.gov/FSA/apfoapp?area=home&subject=prog&topic=nai), color orthoimagery; 2012 GeoEye (http://www.digitalglobe.com/resources/satellite-information) satellite imagery; 1:24,000-scale topographic maps and associated shaded-relief imagery; and, limited use of lidar imagery. This geologic map compilation is based, in part, on previous mapping and reflects varying degrees of new synthesis and reinterpretation. Mapped surficial deposits and descriptions reflect reinterpretation and reclassification of units and revisions to geographic extent, lithologic character and map unit representation, particularly with respect to mapping of tills in glaciated valleys on the east flanks of the Sangre de Cristo Mountains and Culebra Range. Bedrock mapping represents a regional synthesis of geologic data compiled and published over the past quarter century and necessarily includes both simplification and expansion of previously published data with respect to the adopted stratigraphic nomenclature and aerial depiction of map units and faults. Regional and local unit nomenclature is constrained by reference to recently published and previously unpublished 40Ar/39Ar age determinations on Neogene volcanic deposits, the primary Cenozoic stratigraphic markers in the map area. Map unit descriptions rely heavily on previously published data and are simplified to embody the dominant characteristics of map units, particularly where units depicted on large-scale maps were combined for inclusion in this 1:100,000-scale map. Fault depictions are largely simplified and reflect our interpretation of the most regionally significant and better-exposed structures. Previously mapped inferred faults, particularly those buried beneath younger surficial deposits in the San Luis Valley, typically have large locational uncertainties and are poorly dated. Consequently, depiction of these buried faults on this map compilation is minimized. This map provides geologic information suitable for regional lithologic, structure, tectonic, volcanic and surficial geologic interpretation and modeling in support of land-use decision making, subsurface water resource evaluation and determination of regional geologic history. Purpose: This map provides geologic information for making land-use decisions and evaluating subsurface water resources. The map was funded by the National Cooperative Geologic Mapping Program of the U.S. Geological Survey. Supplemental_Information: Map political location: Alamosa, Conejos, Costilla, Huerfano, and Las Animas Counties, Colorado Compilation scale: 1:100,000 Base map used is the U.S. Geological Survey 30’ x 60’ topographic quadrangle for Alamosa, Colorado Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2015 Currentness_Reference: publication date Status: Progress: Complete Maintenance_and_Update_Frequency: none currently planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -106.00000 East_Bounding_Coordinate: -105.00000 North_Bounding_Coordinate: 37.50000 South_Bounding_Coordinate: 37.00000 Keywords: Theme: Theme_Keyword_Thesaurus: AGI Glossary of Geology Theme_Keyword: 40Ar/39Ar age Theme_Keyword: aggregate Theme_Keyword: alluvium Theme_Keyword: amphibolite Theme_Keyword: andesite Theme_Keyword: artificial-fill deposits Theme_Keyword: basalt Theme_Keyword: biotite Theme_Keyword: Cenozoic Theme_Keyword: colluvium Theme_Keyword: dacite Theme_Keyword: debris flows Theme_Keyword: debris-flow deposits Theme_Keyword: fan deposits Theme_Keyword: faulting Theme_Keyword: faults Theme_Keyword: fluvial deposits Theme_Keyword: gabbro Theme_Keyword: glacial deposits Theme_Keyword: glaciofluvial deposits Theme_Keyword: gneiss Theme_Keyword: granite Theme_Keyword: granitic gneiss Theme_Keyword: granodiorite Theme_Keyword: graben Theme_Keyword: gravel Theme_Keyword: hornblende gneiss Theme_Keyword: hyper-concentrated flow deposits Theme_Keyword: lacustrine deposits Theme_Keyword: lake beds Theme_Keyword: landslide deposits Theme_Keyword: Lava Creek B ash Theme_Keyword: leucogranite gneiss Theme_Keyword: loess Theme_Keyword: manmade deposits Theme_Keyword: mass-movement deposits Theme_Keyword: outwash Theme_Keyword: paleosol Theme_Keyword: paleovalley Theme_Keyword: pegmatite Theme_Keyword: periglacial Theme_Keyword: Pleistocene Theme_Keyword: Proterozoic Theme_Keyword: quartz monzonite Theme_Keyword: radiocarbon age Theme_Keyword: radiometric age Theme_Keyword: rhyolite Theme_Keyword: rift Theme_Keyword: Rio Grande rift Theme_Keyword: rock-glacier deposits Theme_Keyword: San Luis basin Theme_Keyword: scarp Theme_Keyword: Servilleta Theme_Keyword: sheetflood alluvium Theme_Keyword: sheetwash alluvium Theme_Keyword: siltstone Theme_Keyword: soil Theme_Keyword: surface-exposure ages Theme_Keyword: surficial deposits Theme_Keyword: talus deposits Theme_Keyword: tephra Theme_Keyword: till Theme_Keyword: U-Pb zircon age Theme_Keyword: volcanic ash Theme_Keyword: volcanic rocks Theme_Keyword: weathering Place: Place_Keyword_Thesaurus: U.S. Board of Geographic Names (BGN) Geographic Names Information System (GNIS) Place_Keyword: USA Place_Keyword: United States Place_Keyword: Colorado Place_Keyword: Alamosa County Place_Keyword: Conejos County Place_Keyword: Costilla County Place_Keyword: Huerfano County Place_Keyword: Las Animas County Place_Keyword: Alamosa Place_Keyword: Alamosa National Wildlife Refuge Place_Keyword: Blanca Place_Keyword: Fort Garland Place_Keyword: Manassa Place_Keyword: La Jara Place_Keyword: Romeo Place_Keyword: San Acacio Place_Keyword: Sanford Place_Keyword: San Luis Place_Keyword: Cove Lake Reservoir Place_Keyword: Sanchez Reservoir Place_Keyword: Smith Reservoir Place_Keyword: Alamosito Creek Place_Keyword: Cat Creek Place_Keyword: Costilla Creek Place_Keyword: Culebra Creek Place_Keyword: La Jara Creek Place_Keyword: Ojito Peak Place_Keyword: Rio Grande Place_Keyword: Rio San Antonio Place_Keyword: Sangre de Cristo Creek Place_Keyword: Vallejos Creek Place_Keyword: South Fork Purgatoire River Place_Keyword: Trinchera Creek Place_Keyword: San Pedro Mesa Place_Keyword: Sangre de Cristo Mountains Place_Keyword: Culebra Range Place_Keyword: Mesita Hill Place_Keyword: Piñon Hills Place_Keyword: South Piñon Hills Place_Keyword: Flat Top Place_Keyword: Mountain Home Reservoir Place_Keyword: Culebra Range Place_Keyword: Conejos River Place_Keyword: San Luis Hills Place_Keyword: Brownie Hills Place_Keyword: Sego Springs State Wildlife Area Place_Keyword: San Pedro Mesa Place_Keyword: Costilla Crossing Bridge Place_Keyword: Fairy Hills Place_Keyword: Cucharas Pass Place_Keyword: Culebra Peak Place_Keyword: Vermejo Peak Place_Keyword: Miranda Peak Place_Keyword: Purgatoire Peak Temporal: Temporal_Keyword_Thesaurus: Geologic Names Committee Lexicon (Geolex) Temporal_Keyword: allostratigraphic Temporal_Keyword: Holocene Temporal_Keyword: Pleistocene Temporal_Keyword: Pinedale Temporal_Keyword: Bull Lake Temporal_Keyword: Pliocene Temporal_Keyword: Oligocene Temporal_Keyword: Miocene Temporal_Keyword: Paleoproterozoic Temporal_Keyword: Eocene Temporal_Keyword: Paleocene Temporal_Keyword: Cretaceous Temporal_Keyword: Jurassic Temporal_Keyword: Triassic Temporal_Keyword: Permian Temporal_Keyword: Pennsylvanian Temporal_Keyword: Paleozoic Temporal_Keyword: Neoproterozoic Temporal_Keyword: Mesoproterozoic Temporal_Keyword: Paleoproterozoic 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 of the data. Although software enables a user to display images at various scales, map data in this report should not be used at scales larger than 1:100,000. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Ren A. Thompson Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing Address: P.O. Box 25046, MS 980 Address: Denver Federal Center City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: 303-236-0929 Contact_Electronic_Mail_Address: rathomps@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: http://pubs.usgs.gov/sim/3342/http://dx.doi.org/10.3133/sim3342map/ Browse_Graphic_File_Description: graphic representation of map layout Browse_Graphic_File_Type: PDF Data_Set_Credit: Theodore Brandt, U.S. Geological Survey, served as primary author of the GIS database. D. Miggins and M. Cosca, U.S. Geological Survey, dated Paleogene igneous rocks using the 40Ar/39Ar method but on different analytical instrumentation using differing methodologies. W. Premo, U.S. Geological Survey, dated Proterozoic igneous rocks using the 207Pb/206Pb zircon (SHRIMP) method. Native_Data_Set_Environment: Windows_XP, Intel ArcInfo version 10.2.2 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Data were entered and checked by the geologist that made the field observations. 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 attribute accuracy, a color check plot was visually compared to the geologist's original compilation. Discrepancies between the digital geospatial dataset and the original analog or digital 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. Logical_Consistency_Report: Map elements were visually checked for overshoots, undershoots, duplicate features, polygon closure, and other errors by the lead author and by the GIS technician(s) that 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 at least one other geologist for consistency with basic geologic principles and general conformity to USGS mapping standards. Completeness_Report: Data are complete: no features that could be accurately represented at the compilation scale of 1:100,000 were eliminated or generalized. The smallest area represented is approximately 50 square meters. All geospatial database elements are attributed. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Most digitized positions on the map that depict distinct contacts between rock formations in the field are estimated to be within 20 m of the actual contact on the land in most instances. Boundaries (lines) between Quaternary units (for example, terrace gravels) that correspond closely to distinct edges of landforms (for example, river terraces) are of comparable accuracy. Boundaries (lines) between some Quaternary units, such as eolian deposits and broad alluvial aprons, are approximately located within an indefinite gradational zone between them. Horizontal positional accuracy is tested by visual comparison of hard copy test plots to source maps or comparing locations of data on a computer monitor to other data layers in the same geographic area. The database contains no elevation data. Accuracy of these digital data indirectly depends on accuracy of the base maps on which the original source geologic maps were compiled. These base maps were made by the U.S. Geological Survey, which routinely checks them for compliance with the National Map Accuracy Standards. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Lewis, R. S. Originator: Derkey, P. D. Title: Digital geologic map of part of the Thompson Falls 1:100,000 quadrangle, Idaho Publication_Date: 1999 Series_Information: Series_Name: U.S. Geological Survey Open File Report Issue_Identification: OFR 99-438 Source_Scale_Denominator: 100000 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1999 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Lewis and Derkey (1999) Source_Contribution: GIS database structure source Process_Step: Process_Description: Geology was mapped during the period 2010 to 2015. Process_Date: 2015 Process_Step: Process_Description: Geologic polygon, line, and point features were attributed and revised in ArcGIS utilizing NAIP imagery, lidar-derived imagery, satellite imagery, and aerial photographs. Process_Date: 2015 Process_Step: Process_Description: Metadata created by Ted Brandt. Process_Date: 2015 Process_Step: Process_Description: Metadata reviewed and revised by Ted Brandt. Process_Date: 2015 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: 5 Ordinate_Resolution: 5 Planar_Distance_Units: METERS Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 13 Transverse_Mercator: Scale_Factor_at_Central_Meridian: .9996 Longitude_of_Central_Meridian: -105.0000 Latitude_of_Projection_Origin: 0.00 False_Easting: 500000.0000 False_Northing: 0.0000 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: The data are supplied in ArcInfo export format, ArcView shapefile format, and ArcGIS geodatabase format. DATABASE STRUCTURE - ArcInfo ==================================== This GIS database includes related look-up tables, which store detailed attribute information. This database structure is more fully described in USGS OFR 99-438 (Lewis and Derkey, 1999). The GIS database structure used in the database includes symbol and pattern items in coverage point, polygon (PAT), and arc (AAT) attribute tables for user convenience. ArcInfo relates for each coverage are saved in a file named .rel. Use the RELATE command with the restore argument at the arc prompt to make the relates active. Alternatively, in ArcTools, use the Relate environment: open dialog in the Manage Relates flyout menu under the ArcTools menu to make the relates active. amgeo coverage: Contains all contact lines and label points for each geologic polygon. In the .pat INFO file the SOURCE item provides a numeric code used to identify the data source for the rock unit. Complete references for the sources listed are listed in the amgeo.ref file. The LABEL item indicates the rock unit label (abbreviation) used to label unit on map. The MLABEL item indicates the rock unit label from the FGDCGeoAgeSubNum font, using geologic age letter symbols associated with the age of the lithologic units (for example: Triassic, Pennsylvanian, Cambrian). The DESC item defines formal or informal unit name. The SYMBOL item contains the shadeset symbol number used by ArcInfo to plot a filled/shaded polygon. The symbol numbers in this item refer to the wpgcmykg.shd shadeset included with the dataset. The PATTERN item contains the pattern number used in the published version of the map. Patterns that correspond with the pattern numbers are displayed in Federal Geographic Data Committee document no. FGDC- STD-013-2006, rev. 2010. There is no ArcInfo shadeset that corresponds to these patterns. In the amgeo.aat INFO file, the LINECODE item provides a numeric Code used to identify type of linear feature. Linecodes less than 100 are used for contacts and boundaries that are described in the amgeo.con file. Linecodes greater than 100 are used for structures that are described in the amgeo.str file. The NAME item lists the name given to the structural feature. The SOURCE item lists the numeric code used to identify the data source for the linear feature. The SYMBOL item lists the line symbol number used by ArcInfo to plot the line (symbol numbers refer to the geol_sfo.lin lineset). Complete references for the sources are listed in the amgeo.ref file. Related look-up table files are amgeo.con, amgeo.str, and amgeo.ref. In the amgeo.con INFO file, the LINECODE item indicates the numeric code (a value less than 100) used to identify type of contact or boundary. The SYMBOL item lists the line symbol number used by ArcInfo to plot the line (symbol numbers refer to the geol_sfo.lin lineset included with the dataset). The TYPE item lists the major type of line (for example, contact, State boundaries, lines of latitude and longitude used for neatlines). The MODIFIER item lists the line type modifier (that is, approximate, concealed, or gradational). No entry implies 'known.' The CERTAINTY item lists the degree of certainty of contact or boundary (that is, inferred or uncertain). No entry implies 'certain.' The DESC item lists the written description or explanation of the contact or boundary. In the amgeo.str INFO file, the LINECODE item indicates the numeric code (a value greater than 100) used to identify type of structure. The SYMBOL item lists the line symbol number used by ArcInfo to plot the line (symbol numbers refer to the geol_sfo.lin lineset included with the dataset). The TYPE item lists the major type of line (for example, fault or fold-axis). The HORIZONTAL item refers to the type of horizontal fault movement (for example, left-lateral or right-lateral). No entry implies 'unknown' or no strike-slip movement. The VERTICAL item refers to the type of vertical fault movement (for example, normal). No entry implies 'unknown' or no dip-slip movement. The FOLD item refers to the type of fold (for example, anticline or syncline). The PLUNGE item refers to the type of plunge on fold (that is, horizontal, plunging, plunging in, or plunging out). The ACCURACY item refers to the line type modifier indicating degree of accuracy (that is, approximately located, concealed, gradational). No entry implies 'certain.' The CERTAINTY item lists the degree of certainty of structure (that is, inferred, uncertain). No entry implies 'certain.' The DESC item lists the written description or explanation of the structure. The INFO structure of these files is listed below: >AMGEO.PAT: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 AREA 8 18 F 5 > 9 PERIMETER 8 18 F 5 > 17 AMGEO# 4 5 B - > 21 AMGEO-ID 4 5 B - > 25 SOURCE 2 5 B - > 27 LABEL 10 10 C - > 37 MLABEL 10 10 C - > 47 DESC 150 150 C - > 197 SYMBOL 2 5 B - > 199 PATTERN 2 5 B - >AMGEO.AAT: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 FNODE# 4 5 B - > 5 TNODE# 4 5 B - > 9 LPOLY# 4 5 B - > 13 RPOLY# 4 5 B - > 17 LENGTH 8 18 F 5 > 25 AMGEO# 4 5 B - > 29 AMGEO-ID 4 5 B - > 33 LINECODE 2 5 B - > 35 NAME 100 100 C - > 135 SOURCE 2 5 B - > 137 SYMBOL 2 5 B - >AMGEO.CON: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 LINECODE 3 3 I - > 4 SYMBOL 3 3 I - > 7 TYPE 10 10 C - > 17 MODIFIER 20 20 C - > 37 CERTAINTY 15 15 C - > 52 DESC 100 100 C - >AMGEO.STR: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 LINECODE 3 3 I - > 4 SYMBOL 3 3 I - > 7 TYPE 10 10 C - > 17 HORIZONTAL 20 20 C - > 37 VERTICAL 20 20 C - > 57 FOLD 15 15 C - > 72 PLUNGE 15 15 C - > 87 ACCURACY 15 15 C - > 102 CERTAINTY 15 15 C - > 117 DESC 100 100 C - > AMGEO.REF: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 SOURCE 4 4 I - > 5 SCALE 8 8 I - > 13 AUTHORS 200 200 C - > 213 YEAR 4 4 I - > 217 REFERENCE 250 250 C - amdikes coverage: Contains lines of dikes In the amdikes.aat INFO file, the LINECODE item provides a numeric code used to identify the type of linear feature. Linecodes are used for structures that are described in the amdikes.str file. The NAME item lists the name given to the structural feature. The SOURCE item lists the numeric code used to identify the data source for the linear feature. The SYMBOL item lists the line symbol number used by ArcInfo to plot the line (symbol numbers refer to the geol_sfo.lin lineset). Complete references for the sources are listed in the amdikes.ref file. Related look-up table files are amdikes.str, and amdikes.ref. In the amdikes.str INFO file, the LINECODE item indicates the numeric code (a value greater than 100) used to identify type of structure. The SYMBOL item lists the line symbol number used by ArcInfo to plot the line(symbol numbers refer to the geol_sfo.lin lineset included with the dataset). The TYPE item lists the major type of line (for example, fault or fold- axis). The HORIZONTAL item refers to the type of horizontal fault movement (for example, left-lateral or right-lateral). No entry implies 'unknown' or no strike-slip movement. The VERTICAL item refers to the type of vertical fault movement (for example, normal). No entry implies 'unknown' or no dip-slip movement. The FOLD item refers to the type of fold (for example, anticline or syncline). The PLUNGE item refers to the type of plunge on fold (that is, horizontal, plunging, plunging in, or plunging out). The ACCURACY item refers to the line type modifier indicating degree of accuracy (that is, approximately located, concealed, gradational). No entry implies 'certain.' The CERTAINTY item lists the degree of certainty of structure (that is, inferred, uncertain). No entry implies 'certain.' The DESC item lists the written description or explanation of the structure. >AMDIKES.AAT: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 FNODE# 4 5 B - > 5 TNODE# 4 5 B - > 9 LPOLY# 4 5 B - > 13 RPOLY# 4 5 B - > 17 LENGTH 8 18 F 5 > 25 AMDIKES# 4 5 B - > 29 AMDIKES-ID 4 5 B - > 31 LINECODE 2 5 B - > 36 NAME 150 150 C - > 181 SOURCE 2 5 B - > 183 SYMBOL 2 5 B - > >AMDIKES.STR: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 LINECODE 3 3 I - > 4 SYMBOL 3 3 I - > 7 TYPE 10 10 C - > 17 HORIZONTAL 20 20 C - > 37 VERTICAL 20 20 C - > >AMDIKES.REF: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 SOURCE 4 4 I - > 5 SCALE 8 8 I - > 13 AUTHORS 200 200 C - > 213 YEAR 4 4 I - > 217 REFERENCE 250 250 C - amfolds coverage: Contains fold axis lines In the amfolds.aat INFO file, the LINECODE item provides a numeric code used to identify the type of linear feature. Linecodes are used for structures that are described in the amfolds.str file. The NAME item lists the name given to the structural feature. The SOURCE item lists the numeric code used to identify the data source for the linear feature. The SYMBOL item lists the line symbol number used by ArcInfo to plot the line (symbol numbers refer to the geol_sfo.lin lineset). Complete references for the sources are listed in the amfolds.ref file. Related look-up table files are amfolds.str, and amfolds.ref. In the amfolds.str INFO file, the LINECODE item indicates the numeric code (a value greater than 100) used to identify type of structure. The SYMBOL item lists the line symbol number used by ArcInfo to plot the line(symbol numbers refer to the geol_sfo.lin lineset included with the dataset). The TYPE item lists the major type of line (for example, fault or fold- axis). The HORIZONTAL item refers to the type of horizontal fault movement (for example, left-lateral or right-lateral). No entry implies 'unknown' or no strike-slip movement. The VERTICAL item refers to the type of vertical fault movement (for example, normal). No entry implies 'unknown' or no dip-slip movement. The FOLD item refers to the type of fold (for example, anticline or syncline). The PLUNGE item refers to the type of plunge on fold (that is, horizontal, plunging, plunging in, or plunging out). The ACCURACY item refers to the line type modifier indicating degree of accuracy (that is, approximately located, concealed, gradational). No entry implies 'certain.' The CERTAINTY item lists the degree of certainty of structure (that is, inferred, uncertain). No entry implies 'certain.' The DESC item lists the written description or explanation of the structure. >AMFOLDS.AAT: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 FNODE# 4 5 B - > 5 TNODE# 4 5 B - > 9 LPOLY# 4 5 B - > 13 RPOLY# 4 5 B - > 17 LENGTH 8 18 F 5 > 25 AMFOLDS# 4 5 B > 29 AMFOLDS-ID 4 5 B - > 33 LINECODE 4 10 B - > 37 NAME 100 100 C - > 137 SOURCE 4 10 B - > 141 SYMBOL 4 10 B - > >AMFOLDS.STR: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 LINECODE 3 3 I - > 4 SYMBOL 3 3 I - > 7 TYPE 10 10 C - > 17 HORIZONTAL 20 20 C - > 37 VERTICAL 20 20 C - > >AMFOLDS.REF: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 SOURCE 4 4 I - > 5 SCALE 8 8 I - > 13 AUTHORS 200 200 C - > 213 YEAR 4 4 I - > 217 REFERENCE 250 250 C - amarage coverage: Contains points recording site-specific observations and measurements of the location and age of dated rock. In the amarage.pat INFO file, the PTTYPE item lists the type of Point symbol (for example, strike and dip of inclined bedding). The SYMBOL item lists the marker symbol used by ArcInfo to identify the type of structural map symbol(symbol numbers refer to the geoscamp2.mrk markerset). The SAMPLENO item contains the sample number/station ID of dated rock samples. The AGE item contains rock-sample ages followed by the measurement tolerances. Both of these values are expressed in million years (Ma). The ANALYST item contains the name of the USGS scientist that analysed the sample. The DISPLAY item indicates with a numeric code whether or not the point is displayed on the publication map layout. The SOURCE item lists the numeric code used to identify the data source. In the amarage.ref INFO file, the SOURCE item lists the numeric code used to identify the data source. The SCALE item lists the scale of the source map. (This value is the denominator of the proportional fraction that identifies the scale of the map that was digitized or scanned to produce the digital map.) The AUTHORS item lists the author(s) or compiler(s) of source map entered as last name, first name or initial, and middle initial. The YEAR item lists the source (map) publication date. The REFERENCE item lists the remainder of the reference in USGS reference format. >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 AREA 8 18 F 5 > 9 PERIMETER 8 18 F 5 > 17 AMARAGE# 4 5 B - > 21 AMARAGE-ID 4 5 B - > 25 PTTYPE 100 100 C - > 125 SAMPLENO 100 100 C - > 225 AGE 100 100 C - > 325 SYMBOL 2 5 B - > 327 ANALYST 100 100 C - > 427 DISPLAY 2 5 B - > 429 SOURCE 2 5 B - > >AMARAGE.REF: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 SOURCE 4 4 I - > 5 SCALE 8 8 I - > 13 AUTHORS 200 200 C - > 213 YEAR 4 4 I - > 217 REFERENCE 250 250 C - amash coverage: Contains points recording site-specific locations and sample numbers of Lava Creek B ash bed locations. In the amash.pat INFO file, the PTTYPE item lists the type of Point symbol (for example, strike and dip of inclined bedding). The SYMBOL item lists the marker symbol used by ArcInfo to identify the type of structural map symbol(symbol numbers refer to the geoscamp2.mrk markerset). The SAMPLENO item contains the sample number/station ID of dated rock samples. The SOURCE item lists the numeric code used to identify the data source. In the amash.ref INFO file, the SOURCE item lists the numeric code used to identify the data source. The SCALE item lists the scale of the source map. (This value is the denominator of the proportional fraction that identifies the scale of the map that was digitized or scanned to produce the digital map.) The AUTHORS item lists the author(s) or compiler(s) of source map entered as last name, first name or initial, and middle initial. The YEAR item lists the source (map) publication date. The REFERENCE item lists the remainder of the reference in USGS reference format. >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 AREA 8 18 F 5 > 9 PERIMETER 8 18 F 5 > 17 AMASH# 4 5 B - > 21 AMASH-ID 4 5 B - > 25 PTTYPE 100 100 C - > 125 SAMPLENO 100 100 C - > 225 SYMBOL 2 5 B - > 227 SOURCE 2 5 B - > >AMASH.REF: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 SOURCE 4 4 I - > 5 SCALE 8 8 I - > 13 AUTHORS 200 200 C - > 213 YEAR 4 4 I - > 217 REFERENCE 250 250 C - amdrill coverage: Contains points recording site-specific observations and measurements of the location and age of drill core samples. In the amdrill.pat INFO file, the PTTYPE item lists the type of Point symbol (for example, strike and dip of inclined bedding). The SYMBOL item lists the marker symbol used by ArcInfo to identify the type of structural map symbol(symbol numbers refer to the geoscamp2.mrk markerset). The AGE1 item contains the first rock-sample depth in feet followed by the sample age with the measurement tolerance followed by the rock unit in parentheses. The AGE2 item contains the second rock-sample depth in feet followed by the sample age with the measurement tolerance followed by the rock unit in parentheses. The AGE3 item contains the third rock-sample depth in feet followed by the sample age with the measurement tolerance followed by the rock unit in parentheses. All age values are expressed in Ma. The SOURCE item lists the numeric code used to identify the data source. In the amdrill.ref INFO file, the SOURCE item lists the numeric code used to identify the data source. The SCALE item lists the scale of the source map. (This value is the denominator of the proportional fraction that identifies the scale of the map that was digitized or scanned to produce the digital map.) The AUTHORS item lists the author(s) or compiler(s) of source map entered as last name, first name or initial, and middle initial. The YEAR item lists the source (map) publication date. The REFERENCE item lists the remainder of the reference in USGS reference format. >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 AREA 8 18 F 5 > 9 PERIMETER 8 18 F 5 > 17 AMDRILL# 4 5 B - > 21 AMDRILL-ID 4 5 B - > 125 PTTYPE 100 100 C - > 225 AGE1 100 100 C - > 275 AGE2 100 100 C - > 425 AGE3 100 100 C - > 575 SYMBOL 2 5 B - > 577 SOURCE 2 5 B - > >AMDRILL.REF: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 SOURCE 4 4 I - > 5 SCALE 8 8 I - > 13 AUTHORS 200 200 C - > 213 YEAR 4 4 I - > 217 REFERENCE 250 250 C - ampts coverage: Contains points recording site-specific observations and measurements, such as strike and dip of bedding In the ampts.pat INFO file, the PTTYPE item lists the type of Point symbol (for example, strike and dip of inclined bedding). The SYMBOL item lists the marker symbol used by ArcInfo to identify the type of structural map symbol(symbol numbers refer to the geoscamp2.mrk markerset). The STRIKE item contains the strike of bedding as well as bearing of lineation or trend of fold axis, where applicable. Strike is an azimuthal angle. Measured in degrees from 0 to 360 in a clockwise direction from North, the STRIKE value also specifies the dip direction, where the dip direction is 90 degrees clockwise relative to the STRIKE. The DIP item contains the dip of bedding as well as plunge angles, where applicable. This value is an angle measured (in degrees from 0 to 90) down from the horizontal; thus a horizontal dip is 0 degrees and a vertical dip is 90 degrees. The SOURCE item lists the numeric code used to identify the data source. In the granpta.ref INFO file, the SOURCE item lists the numeric code used to identify the data source. The SCALE item lists the scale of the source map. (This value is the denominator of the proportional fraction that identifies the scale of the map that was digitized or scanned to produce the digital map.) The AUTHORS item lists the author(s) or compiler(s) of source map entered as last name, first name or initial, and middle initial. The YEAR item lists the source (map) publication date. The REFERENCE item lists the remainder of the reference in USGS reference format. >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 AREA 8 18 F 5 > 9 PERIMETER 8 18 F 5 > 17 AMPTS# 4 5 B - > 21 AMPTS-ID 4 5 B - > 25 PTTYPE 100 100 C - > 125 SYMBOL 2 5 B - > 127 STRIKE 2 5 B - > 129 DIP 2 5 B - > 131 SOURCE 2 5 B - > >AMPTS.REF: > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 SOURCE 4 4 I - > 5 SCALE 8 8 I - > 13 AUTHORS 200 200 C - > 213 YEAR 4 4 I - > 217 REFERENCE 250 250 C - alamhlsd grid: Contains hillshade values derived from U.S. Geological Survey National Elevation Dataset (NED) 10 meter resolution elevation data downloaded on 5-8-15. The grid is included for GIS data users needing a hillshade of this resolution for the entire map area. The grid's projection is the same UTM zone 13 NAD27 datum projection used for the geologic database coverages. The illumination angle for the hillshade's shaded relief grid was generated at an azimuth of 315 degrees and horizon angle of 45 degrees. In the integer grid's alamhlsd.vat INFO file, the VALUE item lists integer values that describe the illumination level of a cell or group of cells forming a zone. The COUNT item list the number of cells in a zone. In the grid's alamhlsd.sta INFO file, the MIN item contains the minimum value, the MAX item contains the maximum value, the MEAN item contain the average value, and the STDV item contains the standard deviation. >ALAMHLSD.VAT > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 VALUE 4 10 B - > 5 COUNT 4 10 B - >ALAMHLSD.STA > >COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME > 1 MIN 8 15 F 3 > 9 MAX 8 15 F 3 > 17 MEAN 8 15 F 3 > 25 STDV 8 15 F 3 >Coding of LABEL and DESC attributes in the amgeo coverage: >LABEL | DESC >af | Artificial fill (latest Holocene) >Breccia | Sheared to granulated rocks mostly of Paleoproterozoic age in broad breccia zones typically along and adjacent to major high- to low-angle faults >Js | Jurassic sedimentary rocks, undivided (Jurassic) >JTRs | Jurassic and Triassic sedimentary rocks, undivided (Jurassic and Triassic) >Kdp | Dakota Sandstone and Purgatoire Formation, undivided (Lower Cretaceous) >Kpu | Pierre Shale, Niobrara Formation, Carlile Shale, Greenhorn Limestone, and Graneros Shale, undivided (Upper Cretaceous) >Kvt | Vermejo Formation and Trinidad Sandstone, undivided (Upper Cretaceous) >Pm | Madera Formation (Middle Pennsylvanian) and Sandia Formation, undivided (Middle and Lower Pennsylvanian) >PPs | Sangre de Cristo Formation (Lower Permian to Middle Pennsylvanian) >PzZg | Gabbro dikes and intrusive bodies (Early Paleozoic? or Neoproterozoic?) >Qa | Channel and flood-plain alluvium, undivided (Holocene) >Qaa | Channel alluvium (late Holocene) >Qac | Alluvium and colluvium, undivided (Holocene to middle? Pleistocene) >Qai | Intermediate alluvium (late and middle Pleistocene) >Qao | Older alluvium (middle Pleistocene) >Qau | Young alluvium, undivided (Holocene and late Pleistocene) >Qay | Younger alluvium (late Pleistocene) >Qba | Basaltic andesite of Mesita cone (early Pleistocene) >Qc | Colluvium (Holocene to middle? Pleistocene) >Qed | Eolian dune sand (Holocene) >Qeo | Older eolian sheet and dune sand (late Pleistocene) >Qey | Younger eolian sheet and dune sand (Holocene) >Qfp | Flood-plain alluvium (Holocene) >Qlal | Lagoonal deposits of Lake Alamosa (middle Pleistocene) >Qlas | Shoreline deposits of Lake Alamosa (middle Pleistocene) >Qlp | Lake and pond deposits (Holocene and latest Pleistocene?) >Qls | Landslide deposits, undivided (Holocene to middle Pleistocene) >Qlsb | Landslide blocks (Holocene to middle Pleistocene) >Qlso | Older landslide deposits (late and middle Pleistocene) >Qlsy | Younger landslide deposits (Holocene and late Pleistocene) >Qpo | Older piedmont-slope deposits (late and middle Pleistocene) >Qpt | Peat deposits (early Holocene and latest Pleistocene?) >Qpy | Younger piedmont-slope deposits (late Pleistocene) >Qrg | Rock-glacier deposits (Holocene? and latest Pleistocene?) >Qsm | Spring-mound deposits (Holocene) >Qta | Talus deposits (Holocene to middle? Pleistocene) >Qtb | Till of Bull Lake age (late and middle Pleistocene) >Qti | Till of Pinedale age and till of Bull Lake age, undivided (late and middle Pleistocene) >QTla | Alamosa Formation of Siebenthal (1910) (middle Pleistocene to Pliocene) >Qtp | Till of Pinedale age (late Pleistocene) >QTsf | Santa Fe Group, upper part (middle Pleistocene to Pliocene) >Tb | Basaltic andesite and trachyandesite, undivided (Miocene) >Tba | Andesite and dacite of San Pedro Mesa (Miocene) >Tbb | Basaltic andesite of San Pedro Mesa (Miocene) >Tch | Cuchara Formation (Eocene) >Tcl | Conejos Formation, lower part (Oligocene) >Tcu | Conejos Formation, upper part (Oligocene) >Tdi | Dacite porphyry (Oligocene) >Tdt | Dacite porphry and tuff (Miocene) >Tcs | Conglomerate and sandstone (Oligocene?) >Tgr | Rhyolite porphyry and dacite (Miocene and Oligocene) >Th | Hinsdale Formation (Oligocene) >Ti | Intrusive rocks, undivided (Miocene and Oligocene) >Tiq | Quartz monzonite (Oligocene) >TKs | Poison Canyon and Raton Formations, undivided (Paleocene and Upper Cretaceous) >Toa | Olivine andesite (Pliocene) >TRs | Triassic sedimentary rocks, undivided (Triassic) >Tsb | Servilleta Basalt (Pliocene) >Tsf | Santa Fe Group, lower part (Pliocene to Oligocene) >Tsfv | Santa Fe Group, volcaniclastic deposits (Miocene and Oligocene) >Tv | Volcanic rocks, undivided (Oligocene) >Tvl | Volcanic lahar and breccia deposits (Oligocene) >w | Open water >Xag | Augen gneiss of Carneros Creek area (Paleoproterozoic) >Xg | Gneissic monzogranite of State Line Peak area (Paleoproterozoic) >Xgg | Granitic orthogneiss of Trinchera Peak area (Paleoproterozoic) >Xma | Amphibolite (Paleoproterozoic) >Xms | Metasedimentary rocks (Paleoproterozoic) >Xmv | Metavolcanic rocks (Paleoproterozoic) >Xp | Pegmatite (Paleoproterozoic) >Xr | Alkali Granite Gneiss (Paleoproterozoic) >Xsv | Interbedded metasedimentary and metavolcanic rocks, undivided (Paleoproterozoic) >Coding of LINECODE and NAME attributes in the amgeo coverage: >LINECODE | NAME >1 | Contact - Certain >2 | Contact - Approximately located >12 | Contact - Approximately located, queried >26 | Crest of lacustrine spit or barrier bar – Certain >29 | Paleoshoreline - Certain >31 | Paleoshoreline - Inferred >41 | Shoreline >81 | Map boundary >91 | Landslide scarp - Certain >92 | Landslide scarp - Approximately located >101 | Fault - Certain >102 | Fault - Approximately located >103 | Fault - Concealed >108 | Fault - Approximately located, queried >111 | Normal fault - Certain >112 | Normal fault - Approximately located >113 | Normal fault - Concealed >117 | Normal fault - Inferred >141 | Strike-slip fault, left-lateral offset - Certain >143 | Strike-slip fault, left-lateral offset – Concealed >151 | Strike-slip fault, right-lateral offset – Certain >152 | Strike-slip fault, right-lateral offset – Approximately located >153 | Strike-slip fault, right-lateral offset – Concealed >171 | Thrust fault - Certain >172 | Thrust fault - Approximately located >173 | Thrust fault - Concealed >537 | Fault - Inferred >596 | Fault scarp - Certain >Coding of LINECODE and NAME attributes in the amdikes coverage: >LINECODE | NAME >505 | PzZg dike - Certain >505 | Ti dike – Certain >Coding of LINECODE and NAME attributes in the amfolds coverage: >LINECODE | NAME >401 | Anticline - Certain >402 | Anticline - Approximately located >403 | Anticline - Concealed >413 | Syncline - Certain >415 | Syncline - Concealed >437 | Overturned anticline - Certain >Coding of PTTYPE attributes in the amarage coverage: >PTTYPE >40Ar/39Ar biotite - plateau age >40Ar/39Ar hornblende - plateau age >40Ar/39Ar sanidine - plateau age >40Ar/39Ar whole rock - integrated age >40Ar/39Ar whole rock - isochron age >40Ar/39Ar whole rock - plateau age >U-Pb age - Zircon >Coding of PTTYPE attributes in the ampts coverage: >PTTYPE >Horizontal bedding >Inclined bedding - Showing strike and dip >Overturned bedding - Showing strike and dip >Vertical bedding - Showing strike >Coding of PTTYPE attributes in the amash coverage: >PTTYPE >Lava Creek B ash bed location >Coding of PTTYPE attributes in the amdrill coverage: >PTTYPE >Location of drill hole - Location of Energy Operating Co. Williamson No. 1 well Auxiliary files: geol_sfo.lin: This lineset file defines geologic line types in the geologically themed coverages. geoscamp2.mrk: This markerset file defines the geologic markers in the geologically themed coverages. wpgcmykg.shd: This shadeset file defines the cmyk values of colors assigned to polygons in the geologically themed coverages. 3342map.pdf: A print optimized file for viewing and printing a graphics version of the map and accessory elements using Adobe Acrobat viewing software (version 11.0). (Adobe Acrobat viewing software is free and can be downloaded at the following URL: http://get.adobe.com/reader/ Entity_and_Attribute_Detail_Citation: http://wrgis.wr.usgs.gov/open-file/of99-438/ Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing address Address: USGS Information Services Address: Box 25286 Address: Denver Federal Center City: Denver State_or_Province: CO Postal_Code: 80225-0046 Contact_Voice_Telephone: 1-(888)-ASK-USGS Contact_Electronic_Mail_Address: http://ask.usgs.gov Resource_Description: Scientific Investigations Map 3342 Distribution_Liability: This database, identified as SIM 3342, has been approved for release by the U.S. Geological Survey (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 U.S. Government may be held liable for any damages resulting from its authorized or unauthorized use. Although these data have been processed successfully on a computer System at the U.S. Geological Survey (USGS), no warranty, expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. The USGS or the U.S. Government shall not be held liable for improper or incorrect use of the data described and/or contained herein. Although this information product, for the most part, is in the public domain, it also may contain copyrighted material as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: ARCE,SHP,GDB Format_Version_Number: 10.2.2 Format_Version_Date: 2014 File_Decompression_Technique: In Windows, use WinZip (http://www.winzip.com/) or other programs to extract the file. Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://dx.doi.org/10.3133/sim3342 Network_Resource_Name: http://pubs.usgs.gov/sim/3342/ Fees: none Metadata_Reference_Information: Metadata_Date: 2015 Metadata_Review_Date: 2015 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Theodore Brandt Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing address Address: U.S. Geological Survey Address: MS 980, Box 25046 Denver Federal Center City: Denver State_or_Province: CO Postal_Code: 80225-0046 Contact_Voice_Telephone: 303-236-1901 Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998