DIGITAL DATABASE FOR THE QUATERNARY GEOLOGIC MAP OF THE DAKOTAS QUADRANGLE, UNITED STATES
MISCELLANEOUS INVESTIGATIONS SERIES I-1420 (NL-14)

Files available through this site represent the digital component of the
	Dakotas Quadrangle of the Quaternary Geologic Atlas of the U.S., 
	Miscellaneous Investigations Series, Map I-1420 (NL-14).  The files
	contain .e00 files, shapefiles, and pdf files of the map's illustrations
	and correlation diagram, and pdf files of the map unit descriptions and
	sources of information.  An ARC/INFO aml, keyfiles and shadeset
        are included to produce the plot of the data.  


The following ARC/INFO export coverages are included in dakotasGIS.zip:

	>geo_net--map unit polygons and open water; lines that are geologic
		contacts and shorelines.
          
	>gla_lin--a line coverage of linear glacial features

	>gla_pnt--a point coverage of glacial point data

        >strat_pnt--a point coverage of important stratigraphic locations

	>hydr_lin--a line coverage indicating locations of streams and water bodies

	>topo_lin--a line coverage containing contour lines

	>bnd_lin--a line coverage with a neatline and state boundary lines

	>bnd_net--a polygon coverage containing county and administrative areas

	>rd_lin--a line coverage of state and federal highways in the U.S.

	>rr_lin--a line coverage of railroads

	>grid_lin--a line coverage of 1 degree projection lines


Included in dakotasIMG.zip: 

	I-1420_nl-14_map.pdf--A scan of the original published paper map

	I-1420_nl-14_plotfile.pdf--A plot of the digital files
		containing map units, glacial features, hydrology,
            	topography, state boundaries, and list of map symbols

	dakotas.txt--an ASCII file of FGDC formal metadata

	I-1420_nl-14_correlation.pdf--A scan of the diagram showing
             	correlation of map units

	I-1420_nl-14_drainage.pdf--A scan of the illustration showing the
		ancestral drainage at the time of earliest Quaternary glaciation 

	I-1420_nl-14_lobes.pdf--A scan of the illustration showing the
		relationship of the glacial ice lobes, limits of glacial 
		advances, and glacial phases.

	I-1420_nl-14_stratsec.pdf--A scan of the illustration showing the
		locations and descriptions of important stratigraphic locations

	I-1420_nl-14_index.pdf--An index map showing location of
      	       Quaternary Geologic Atlas of the U.S. quadrangles

	I-1420_nl-14_responsibility.pdf--A scan of the illustration of
            	compilation responsibilities shown on the paper map

	I-1420_nl-14_textonly.pdf--Text description of map units, figure
	      	captions, and sources of information used in preparing the
            	original map
	I-1420_nl-14_table1.pdf--A scan of the table showing tentative 
		correlation and ages of glacial phases and drifts.

	I-1420_nl-14_table2.pdf--A scan of the table showing tentative 
		correlation of Quaternary deposits in northeastern Montana, 
		northwestern, west-central, and south-central North Dakota, 
		and north-central South Dakota.

Also available in the file dakotasAV.zip are the ArcView shape files of the
            Arc/Info coverages

  Charles A. Bush
  U.S. Geological Survey                                                     
  (303) 236-4723
  cbush@usgs.gov