The following document was scanned from Professional Paper 901, which is out
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Introduction ------------------------------------------- 1
Previous geologic maps of the United States ------------- 1
Sources of information ------------------------------- 1
Maps published before 1860 -------------------------- 1
Maps between 1860 and 1880 ------------------------- 7
Maps between 1880 and 1930 ------------------------- 7
The Geologic Map of the United States of 1932 ------ 9
The Geologic Map of the United States ------------------ 10
History of the present project----------------------- 10
Sources of the Geologic Map ------------------------- 11
Uses of the Geologic Map --------------------------- 18
Methods of compilation ----------------------------- 18
Contents of the Geologic Map ------------------------ 20
Classification of the rock units -------------------- 21
Symbolization of rock units ------------------------ 25
Representation of faults ---------------------------- 28
Representation of contacts -------------------------- 31
Subcrop geology ------------------------------------- 31
Northern Interior States ------------------------- 31
Eolian deposits --------------------------------- 35
Atlantic Coastal Plain---------------------------- 36
Radiating strikes------------------------------------ 36
References cited---------------------------------------- 38
FIGURE 1. Geology of the United States as represented by Maclure
(1817) ---------------------------------------------------- 1
2. Geology of the United States and adjacent parts of Canada
as represented by Lyell (1845) --------------------------- 4
3. Geology of the United States and adjacent parts of Canada
as represented by Marcou (1855) -------------------------- 5
4. Geology of the United States and adjacent parts of Canada
as represented by Edward Hitchcock (1854) ----------------- 6
5. Index map showing areas represented geologically on McGee map
of 1885, areas added or revised on the McGee map of 1894,
and additional coverage based on less exact information on
the C. H. Hitchcock map of 1887 --------------------------- 8
6. Index map of Texas, showing areas covered by different
sources used on the Geologic Map -------------------------- 17
7. Index map of the United States, showing areas covered by the
different sources used for the subsea contours on the
Geologic Map ---------------------------------------------- 19
8. Geologic maps of the Sandia Mountains, New Mexico, to
illustrate the process of generalizing data for the
Geologic Map of the United States ------------------------- 22
9. Map of the Great Basin in Nevada and Utah, showing
regional extent of major low-angle thrust faults that are
represented on the Geologic Map of the United States as
exposed fragments in the mountain areas ------------------- 29
1O. Circular faults shown on the Geologic Map of the United
States ---------------------------------------------------- 30
11. Maps of eastern South Dakota, to illustrate problems of
representing bedrock geology in areas with extensive cover
of surficial deposits ------------------------------------- 32
12. Generalized geologic map of eastern Middle Western States, to
show relations of subcrop geology to preglacial river
systems --------------------------------------------------- 33
13. Geologic map of northern Minnesota, showing the extent of
thin Upper Cretaceous deposits (Coleraine Formation) that
are not represented on the Geologic Map of the United
States ---------------------------------------------------- 34
14. Map of western Nebraska, showing bedrock geology as represented
on the Geologic Map of the United States, superposed on
which are the areas of Quaternary sand dunes and drifted
sand (Sand Hills Formation) as represented on the Geologic
Map of the United States of 1932 and by Thorp and
Smith (1952) ---------------------------------------------- 35
15. Geologic map of the Atlantic Coastal Plain in Maryland,
Delaware, and New Jersey, showing the relation of the
bedrock units that appear on the Geologic Map of the United
States to surficial deposits of Quaternary and late
Tertiary age ---------------------------------------------- 37
16. Map of the southern Midcontinent region in Oklahoma, Arkansas,
and Texas, showing "radiating strikes" in Paleozoic and
Cretaceous rocks ------------------------------------------ 38
TABLE 1. Comparison between "American" and "International" systems
of coloring stratified rocks on maps ---------------------- 27
The U.S. Geological Survey has published a new Geologic Map of the United States (exclusive of Alaska and Hawaii) on a scale of 1:2,500,000, which was compiled between 1967 and 1971 by Philip B. King and Helen M. Beikman, with geologic cartography by Gertrude J. Edmonston. The map replaces the now outdated Geologic Map of the United States on the same scale, which was compiled by George W. Stose and Olof A. Ljungstedt and was issued by the U.S. Geological Survey in l932.
This report is intended to supplement the new map and to provide background information to assist its user in interpreting it. It describes the historical antecedents of the map and the sources from which the map was compiled and discusses various general topics related to it. Succeeding reports will amplify the necessarily brief descriptions of the map units which appear in its legend and will deal at length with specific geological problems in the United States, insofar as they relate to representation of the features in map form.
Part 2 - Previous Geologic Maps of the U.S.
U.S. DEPARTMENT OF THE INTERIOR
Eastern Mineral Resources Team
This page is https://pubs.usgs.gov/dds/dds11/pp901_html/1_PP901.HTML
Maintained by Eastern Publications Group
U.S. GEOLOGICAL SURVEY
Contact: Paul Schruben
Last revised 11-13-98