U.S. National Geodetic Survey.2010-02-152010-02-151979http://hdl.handle.net/1969.3/2088596 p.This material represents adjusted elevation data derived from work done by the National Geodetic Survey (NGS) under the basic sponsorship of the Harris Galveston Coastal Subsidence District and with the aid of a number of interested federal agencies. The actual field work was completed in January, 1979. The elevations listed here are for specific bench marks and should not be used to represent the elevation of nearby structures, roadways, etc. The 1978 data is expected to be published in July, 1979 and will include maps showing the subsidence which occurred from 1973 to 1978.mapssubsidencegeological dataBook