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| Open-File Report 2004–1430 |

| Geologic Map Compilation of the Upper Seco Creek Area, Medina and Uvalde Counties, south-central Texas |
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| By  Charles D. Blome1, Jason R. Faith2, Edward W. Collins3, Diana        E. Pedraza2, and Kyle E. Murray4 |
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| 1 U.S. Geological Survey, Denver, CO 802252 U.S. Geological Survey,              San Antonio, TX 782493 Bureau of Economic Geology, University Station,              Austin, TX 78713-89244 University of Texas at San Antonio, San Antonio,              TX 78249-1130 |
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| **Version 1.0** |
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| Published 2005  |

| This digital geologic map compilation presents new polygon (map unit      contacts) and line (faults) vector data for the Seco Creek area in south-central      Texas. The map database, which is at 1:50,000-scale resolution, provides      geologic coverage for an area located in Medina County about 25 km northwest      of San Antonio. The map area is underlain by sedimentary rocks of Cretaceous      and Quaternary age that are offset by a series of normal faults. The stratigraphy      ranges from the Lower Cretaceous Glen Rose Limestone (oldest) to Quaternary      (youngest) alluvium. Edwards Group rock units are represented by the Devils      River and Fort Terrett Formations, the latter being equivalent to the lower      part of the Devils River Formation. The impetus for compiling the geology      of the four 7.5 degree-quadrangle (Comanche Waterhole, Flatrock Crossing,      Sabinal NE, and Texas Mountain) area was to provide a digital geologic      map database for a helicopter electromagnetic (HEM) survey flown in 2002      and for ongoing 3-D EarthVision modeling of the Edwards/Trinity aquifer    boundary. |
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| The text of this report is presented here in Portable Document Format.        The latest version of Adobe Acrobat Reader or similar software is required        to view it. If you wish to download the latest version of Acrobat Reader      free of charge, click here . |
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| - OF 2004–1430 Map PDF            file (8.86 MB) | **Digital geologic map for viewing and printing.** |
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| Map Report Text PDF file (14 KB) | **Text-only version of map report.***(This version of the report is    accessible as defined in Section 508.)* |
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| - Map Info PDF file (94 KB) | **Information to accompany the digital geologic map.***(This version of the report is    accessible as defined in Section 508.)* |
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| -  Downloads Directory (Metadata) | **Digital geologic map database directory for download.** |
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| U.S. Department of the Interior | U.S. Geological Survey      URL: https://pubsdata.usgs.gov/pubs/of/2004/1430/Questions or Assistance: USGS Web ContactPage Last Modified: Sat Jan 12 23:52 EDT 2013 |  |

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