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WRIR 01-4210: Hydraulic-Property Estimates for Use With a Transient Ground-Water Flow Model of the Death Valley Regional Ground-Water Flow System, Nevada and California

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APPENDIX A: HYDRAULIC-PROPERTIES DATABASE

A hydraulic-properties database was compiled to support current Death Valley ground-water flow system simulations. The database contains individual worksheets for 10 of the 11 hydrogeologic units (HGU's) in the study area (see table 1 for descriptions). No data were collected, and hence, no worksheet was required, for the crystalline confining unit (XCU). Data reported in the body of the report for the XCU are from Bedinger and others (1989). Entries for each HGU are organized by the well from which data were obtained (the observation well, if different from the pumping or injection well).  
Complete database (Microsoft Excel file):
bullet  Database (970 Kb) -- contains full set of individual worksheets.

Individual worksheets (tab-delimited text files):
image of small text bullet  YAA & OAA (21 Kb) -- Younger and older alluvial aquifers.
image of small text bullet  ACU (6 Kb) -- Alluvial confining unit.
image of small text bullet  LFU (3 Kb) -- Lava flow unit.
image of small text bullet  YVU & VSU (25 Kb) -- Younger volcanic unit and volcaniclastic and sedimentary rocks unit.
image of small text bullet  Tertiary volcanic rocks (93 Kb).
image of small text bullet  OVU (38 Kb) -- Older volcanic unit.
image of small text bullet  ICU (12 Kb) -- Intrusive confining unit.
image of small text bullet  SCU (41 Kb) -- Sedimentary rocks confining unit.
image of small text bullet  UCA & LCA (17 Kb) -- Upper and lower carbonate aquifer.
image of small text bullet  UCCU & LCCU (26 Kb) -- Upper and lower clastic confining units.
image of small text bullet  Data sites (13 Kb).
image of small text bullet  References (23 Kb).

Each entry in the database contains the following information:

  1. Observation well name -- A name commonly applied to the well from which hydraulic-property data were obtained.
  2. USGS site identification (ID) number -- A unique 15-digit number given to all inventoried wells in the USGS National Water Information System (NWIS) database. The site ID number consists of latitude, in degrees, minutes, and seconds, followed by longitude, in degrees, minutes, and seconds, followed by a sequence number. This field was left blank for wells that did not have a site ID number. Because data for wells in Permian sedimentary rocks from the Colorado Plateau that are in the database were obtained from a report in which these wells are identified by their land-net coordinates, a column containing land-net coordinates was added for these wells.
  3. Universal Transverse Mercator (UTM) coordinates (meters). All well coordinates are in UTM zone 11, except those on the Colorado Plateau which are in UTM zone 12.
  4. Land surface altitude at the well (meters). All altitudes are referenced to the National Geodetic Vertical Datum of 1929.
  5. Well depth (meters).
  6. Depths to the top and bottom of the test interval (meters).
  7. Thickness (meters) -- open interval of borehole.
  8. Radius or interwell distance (meters) -- for single-well aquifer tests, the borehole radius was listed if known; if the borehole radius was unknown, the casing radius was listed. For multiple-well aquifer tests, the reported, calculated, or scaled distance between the pumping or injection well and the observation well was listed.
  9. Geologic units and lithologies present in the test interval -- in test intervals spanning several geologic units, negligibly transmissive geologic units were omitted. For the Tertiary volcanics unit, columns describing alteration, degree of welding in ash-flow tuff, and the intensity of fracturing and faulting were added.
  10. Pumped or injection well if different from the observation well (for HGU's with no multiple-well test data, this column was omitted).
  11. Starting and ending test dates.
  12. Length of the analyzed record, in minutes.
  13. Type of aquifer test
  14. Average discharge or injection rate (liters per second).
  15. Analyzed data (typically drawdown, residual drawdown, recovery, specific capacity, or flux).
  16. Hydraulic conductivity (meters per day) -- Depending on available data, columns were added to list horizontal, vertical, fracture, and matrix hydraulic conductivity separately.
  17. Vertical to horizontal anisotropy (for HGU's without data necessary to calculate this property, this column was omitted).
  18. Transmissivity (meters squared per day).
  19. Storativity (unitless).
  20. Specific yield (unitless).
  21. Analytical method, with analyses performed for this study identified.
  22. Sources of hydraulic-property data, the aquifer-test analysis, and supporting data.

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