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Cretaceous Undivided unit bottom depth surface. Areal extent of the data file is based upon the Pecos Valley Aquifer in west Texas. Dataset prepared for the project: Pecos Valley Aquifer, West Texas: Structure and Brackish Groundwater. |
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Cretaceous Undivided unit bottom depth surface. Areal extent of the data file is based upon the Pecos Valley Aquifer in west Texas. Dataset prepared for the project: Pecos Valley Aquifer, West Texas: Structure and Brackish Groundwater. |
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Texas Water Development Board (www.twdb.state.tx.us), Water Science and Conservation, Groundwater Division, Brackish Resources Aquifer Characterization System Program |
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5000 |
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<DIV STYLE="text-align:Left;"><DIV><DIV><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>Cretaceous Undivided Unit, Bottom Depth Surface Grid</SPAN></SPAN></P><P><SPAN><SPAN>Units: feet below ground surface, integer value</SPAN></SPAN></P><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>The formation surface of the unit was derived from analysis of water well, geophysical well log, and review of previously published reports. Point values were first processed using Spatial Analyst, topo to raster tool. Contours were created using the contour tool, which were then manually edited to conform to the geology and well point values. The contour polylines were converted to points using the feature vertices to points tool and assigned latitude/longitude coordinates. All contour points and well points were then interpolated using the natural neighbor tool and the surface was created in a grid format and snapped to the project grid with a 250 foot cell size. </SPAN></SPAN></P><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>Some formation surfaces required work to exclude the outcrop areas of other formations. The outcrop extents were derived from the Texas Digital Geologic Atlas. The Raster Calculator tool was used for grid manipulation. Surfaces were checked against the digital elevation model surface in the project area to assure that the formation surface did not porpoise above land surface; if this occurred, the formation surface was corrected with the DEM. Each formation surface was also checked against the overlying or underlying formation surfaces to ensure consistency. Each formation surface was clipped to the extent of the formation boundary. The last step in surface preparation involved converting the well point surface values to a grid and replacing the formation surface values with the values at each well point, assuring the well point stratigraphic values matched the formation surface. </SPAN></SPAN></P><P><SPAN><SPAN>This dataset was prepared to meet a specific purpose as described in the following report, which is available on the TWDB website:</SPAN></SPAN></P><P><SPAN><SPAN>Meyer, J.E., Wise, M.R., and Kalaswad, S., 2011, Pecos Valley Aquifer, West Texas: Structure and Brackish Groundwater: Texas Water Development Board, report in preparation.</SPAN></SPAN></P><P><SPAN><SPAN>The data used to prepare this dataset is also available in the Brackish Resources Aquifer Characterization System (BRACS) MS Access Database, data dictionary, and raw data files (digital geophysical well logs and water well information).</SPAN></SPAN></P><P><SPAN /></P></DIV></DIV></DIV> |
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BRACS PVA Project: Cretaceous Undivided Bottom Depth Surface Grid |
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["TWDB BRACS","Pecos Valley Aquifer","PVA","Salinity","Cretaceous stratigraphy"] |
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en-US |
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150000000 |
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