NOTE: This file contains transcribers notes to accompany the original README file (aldb.txt).

This data is a conversion product and should not serve as the primary source for the complete geologic information for this area. To obtain complete information, please go to https://pubs.usgs.gov/of/1996/of96-252/   This information may be found as referenced below:

Publisher:  	U.S. Geological Survey
Title:  	Preliminary geologic map emphasizing bedrock formations in Alameda County, California: a digital database
Author(s): 	Graymer, R.W., Jones, D.L., and Brabb, E.E.
Original NGMDB identifier:  22969

Purpose: This file set is intended to make outdated Arc/INFO e00 files available as open-format shapefiles. No modification to files has been made. Projection was not changed. 

Process: e00 files were imported to coverage, then converted to shapefile using the ArcMap commands Import from e00 (conversion) and Feature Class to Feature Class respectively. Related tables were preserved by opening in ArcMap and exporting to txt.   

E00 files convert to:

	al_um-py.e00 (Faults, depositional contacts, and rock unit identities) =
		al_um_py_anno.shp
		al_um_py_arc.shp
		al_um_py_polygon.shp
		al_um_py.lut.txt

	al_um-sr.e00 (Fold axes, strike and dip information) =
		al_um_sr_pt.shp
		al_um_sr_ar.shp
		al_um_sr_anno.shp
		al_um_sr.lut.txt
		al_um_sr.lut2x.txt
	
	al_um-flt.e00 (Map of faults and fold axes in Alameda County with additional database items containing fault name if any) =
		al_um_flt_anno.shp
		al_um_flt_arc.shp
		al_um_flt_route.shp

	al_so.e00 (Index map of sources of data) = 
		al_so_anno.shp
		al_so_arc.shp
		al_so_polygon.shp
	
	al_as.e00 (Index map of Assemblages in Alameda County) = 
		al_as_anno.shp
		al_as_label.shp
		al_as_arc.shp

	al_corr.e00 (Correlation table for the units in this map database) = 
		al_corr_anno.shp
		al_corr_arc.shp
		al_corr_polygon.shp


Original files included:
	algeo.txt = detailed unit descriptions and geological information, plus sources of data and references cited.
	aldb.txt = readme (includes file and attribute descriptions)


Modified: 14 April, 2023 by Karen Morgan, USGS contractor



