PROFESSIONAL PAPER 1411-A

PZ Thickn f and depth to t if Paleozoi ks—PLATE 3

a USGS U.S. DEPARTMENT OF THE INTERIOR els, AL 22, Geno Plame ets ne Ups Calero er Bsn

science fora changing world U.S. GEOLOGICAL SURVEY Arizona; Colorado, New Mexico, Utah, and Wyoming, excluding the San Juan Basin
110°

EXPLANATION

im Area where the Paleozoic rocks crop out (generalized). Blue
indicates Canyonlands aquifer, purple indicates geologic
units below Canyonlands aquifer

Fontenelle
Reservoir i

oe 0 Area where the Paleozoic rocks are missing because of
erosion or nondeposition or are thrust beneath Precambrian
rocks

| Area where the top of the Paleozoic rocks is below the
Canyonlands aquifer (see table 1 for component
geologic units)

Rock {Springs

Thickness of Paleozoic rocks

—1,000— Line of equal thickness of Paleozoic rocks, excluding
Paleozoic rocks above Charleston Thrust Fault in
Strawberry Valley area, Utah—Interval generally
is 1,000 feet; 2,000 feet in northwestern Colorado
near Sawatch Range because of abrupt thickness changes

WYOMING © River
SOLORADQ

Depth to top of Paleozoic rocks
—s,000o— Line of equal depth to top of Paleozoic rocks—Interval

Sener north of Uncompahgre Plateau is 5,000 feet; interval to
falley area. south is 2,500 feet
Sources of information used to complete rces
depth to top of Paleozoic rocks map Sout for area
A A: Richmond (1945); Wanless and others (1955)

B: Hansen (1965b); Schell (1969)

C: Huddle and McCann (1947b); Huddle and others
(1951); Bissell (1952); Baker (1976);
Bruce Bryant (U.S. Geological Survey,
oral commun., 1990)

D: Donner (1949); Bass and others (1955);
\ Severy (1955); Sharps (1955); Bass and
B ‘ Northrop (1963); Segerstrom and Young (1972);
= ah Stewart and others (1972a, 1972b); Snyder

wae (1980a, 1980b); and American Stratigraphic Company
(unpublished drilling logs)
E: Hubert (1954); Stewart and others (1972a);
Bryant and Martin (1988)
F: Welder (1954); Freeman (1971, 1972);
Stewart and others (1972a)

G: Thomas and others (1945); Mull (1960);
Bass and Northrop (1963); Lohman (1965);
Gaskill and Godwin (1966a, 1966b); Gaskill
and others (1967); Godwin (1968); Stewart
and others (1972a, 1972b); Collins (1977);
and Maclachlan (1987)

|
|
SE
—
WB
| i>
I

I H: Eckel and others (1949); Cater (1955a, 1955b);
NEW MEXICO Cater and others (1955); Bush and others (1959,
qige- hes cts, 1960); Donnell (1960); Luedke and Burbank (1962);
Sy BOUNDARY OF BOUNDARY OF FROM STUDY Stewart and others (1972a); and American
2 UPPER COLORADO UPPER COLORADO Stratigraphic Company (unpublished drilling logs)

RIVER BASIN ¥ RIVER BASIN

Except where noted, map prepared from I: Zapp (1949)

puny

7 Gog soca MU eraint tee J: Harshbarger and Repenning (1954); Strobell (1956);
“a, Spanes g ( eee, ee Fe Cooley and others (1964); Stewart and others (19722);
5,000 : ‘ ‘ , equivalents (both from Geoffrey Freethey and Hackman and Olson (1977)
~ : : : i el ates epee es K: Gregory and Moore (1931); Phoenix (1963);
37°: UTAH Ss | 5 Q ; - thickness of Chine and Moenkopi Witkind and Thaden (1963); Cooley and others
=a Navajo : 7 Navajo Formations and equivalents, either from (1964); Stewart and others (1972a, 1972b);
ARIZONA = eel : Reservoir et Freethey and Cordy (written commun., and American Stratigraphic Company (unpublished
§ e . 1984-85) in shaded area or Stewart and aninsilees)
a, 4 3 Hoes ge . others (1972, 1972b) in unshaded area
112° : ayia : |
Ny U |
—i11 o : 711° -
“a AREA EXCLUDED FROM STUDY 4 110° ) ¢ AREA EXCLUDED FROM STUDY \
oa 3 ' f :
: ~ | ey
-* P20 Zz “107° ar 4 . hee
36" ae 36° q > ; 36°
+... S08

LLo% VV % 2
am 1 ‘5 a

108° 108°
1:2,000,000 1:2,000,000
0 25 50 75 ais MILES 0) 25 50 75 100 MILES
|
f T T ii T T T 1 T !
0 25 50 75 100 KILOMETERS ) 25 50 75 100 KILOMETERS
THICKNESS OF PALEOZOIC ROCKS DEPTH TO TOP OF PALEOZOIC ROCKS

Fc ee THICKNESS AND DEPTH TO THE TOP OF THE PALEOZOIC ROCKS THAT COMPRISE HYDROGEOLOGIC UNITS IN THE UPPER COLORADO RIVER BASIN AND VICINITY
IN ARIZONA, COLORADO, NEW MEXICO, UTAH, AND WYOMING
By
Arthur L. Geldon