Notes on the oil and gas fields of Webb and Zapata counties. The underground position of the Austin formation in the San Antonio oil fields

EXCHANGE

University of Texas Bulletin

No. 2230: August 8, 1922

Notes on the Oil and Gas Fields of
Webb and Zapata Counties

The Underground Position of the Austin

Formation in the San Antonio

Oil Fields

BY
E. H. SELLARDS

Bureau of Economic Geology and Technology

Division of Economic Geology
J. A. Udden, Director of the Bureau and Heatf of the Division

PUBLISHED BY
THE UNIVERSITY OF TEXAS

AUSTIN

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HAL C. WEAVER

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E44-8C2-2m

University of Texas Bulletin

Xo. 22,'JO: Ai.feiisfc 8, 11

Notes on the Oil and Gas Fields of
Webb and Zapata Counties

The Underground Position of the Austin

Formation in the San Antonio

Oil Fields

BY
E. H. SELLARDS

Bureau of Economic Geology and Technology

Division of Economic Geology
J. A. Udden, Director of the Bureau, and Head1 of the Division

PLRL1SHED BY THE UNIVERSITY FOUR TIMES A MONTH, AND ENTERED AS.

SECOND-CLASS MATTER AT THE POSTOFFICE AT AUSTIN,

TEXAS, UNDER THE ACT OF AUGUST 24, 1912

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The benefits of education and of
useful knowledge, generally diffused
through a community, are essential
to the preservation of a free govern-
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Sam Houston.

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EXCHANGE

CONTENTS

Notes on the Oil and Gas Fields of Webb and
Z a pat a Counties

PAGE

SUratigraphic Geology 5

Regional Dip 6

Topographic Features 6

Location of the Oil and Gas Fields with Respect to Topo-
graphic Features.. . 8

Charco-Redoiido Wells 8

Jennings Gas Field 0

The Mirando Pool. 9

The Riser Gas Field 10

The Schott Pool 10

The Carolina-Texas Oil Company Gas Wells. 11

Well Records 12

Well Logs in Webb County 13

Well Logs in Zapata County 24

The Underground Position of the Austin Formation
in the San Antonio Oil Fields

PAGE

Introduction 30

General Structural Conditions in the San Antonio District. . 32

Contour Map on the Austin Formation 33

Structural Conditions as Indicated by Contouring on the

Austin Formation 34

Relation of Producing Wells to Structure 37

Producing Formations 38

Well Records 38

LIST OF ILLUSTRATIONS

PAGE

Map of Webb and Zapata County Oil Fields 7

Map Showing Underground Position of Austin Formation . . 35

977634

NOTES ON THE OIL AND GAS FIELDS OF WEBB AND
ZAPATA COUNTIES:

BY E. H. SELLARDS

At the present time oil or gas is being obtained from several
localities in Webb and Zapata counties. The localities include
the Charco Redondo oil wells, Jennings gas pool, and Mirando
oil pool in Zapata County, and the Reiser gas wells and Schott
oil pool and the gas wells of the Carolina-Texas Oil Com-,
pany in Webb County. Of these several localities, the Reiser
field is the oldest as a commercial field, having been discovered
in 1909, although previous to that time oil had been noted in
shallow wells drilled for water at the Charco Redondo. Ranch.
The following notes 011 the producing fields of these two counties
are based- on a reconnaisance of about ten days made in April
and May, 1922.

Stratigraphic Geology

At the March meeting of the American Association of Petro-
leum Geologists, Dr. A. C. Trowbridge read a paper on the
Coastal Plains formations in Texas, adjacent to the Rio Grande,
which it is understood, will be published. Not wishing to antici-
pate in any way the results given in this paper by Trow-
bridge, the geology and stratigraphy of this area will be referred
to at this time only in a very general way.

Immediately at Laredo and for a few miles to the east, the
rocks exposed in the stream beds and rock cuts are chiefly sand-
stones, often glauconitic, probably representing the Cook Moun-
tain formation. Next to the east and extending almost, if not
quite, to Reiser, is a broad belt in which clays predominate,
although some oyster shell beds are included. These clays rep-
resent the Yegua formaton. About twenty-two miles east of
Laredo (three miles west of Reiser) is found a belt of very
sandy land which may possibly represent a remnant of the

Manuscript submitted for publication August, 1922. Issued Sep-
tember, 1922.

6 I'nh'ersity of Texas Bulletin

Fayette, or a sandy horizon in the Yegua. At Reiser and in
a clay pit nearby, are seen clays and oyster shall beds not
unlike those of the Yegua.

Next east of Reiser, near Aguilares, and extending thence
north and south is a belt of country in which the land is in
places sandy and in which there ar$ occasional outcrops of a
light-colored rock with a limited amount of sand. This rock,
which in places is chietiy volcanic ash containing plant impres-
sions,- probably represents the Fayette formation. Next to the
east is found a belt of clay land which widens in the northern
part of Webb County and possibly represents the Frio formation.

About thirty-five miles east of Laredo is a prominent escarp-
ment beyond which the land is level and slopes gradually to
the east. The formation capping this escarpment is the
Reynosa,. which consists of caliche filled gravel and in places of
caliche rock. The age of this formation is either Pleistocene or
Pliocene. In the face of the escarpment, underneath the
Reynosa capping, there is found in places a coarse sandstone
which may be of Miocene age.

It is thus seen that the formations found at the surface are
chiefly those of the Eocene series, together with possibly limited
Miocene exposures, and in the eastern part of these two counties,
the Reynosa limestone and gravels. Adjacent to the stream beds,
of course, are Pleistocene and recent terrace deposits,

Regional Dip

The regional dip in this area is to the east. To the north and
northeast of this area, the strike of both Eocene and Cretaceous
formations is northeast-southwest, the dip being southeast. In
the central and southern parts of Webb and in Zapata counties,
the strike of the Eocene formations is approximately north-
south, the dip being, as stated, to the east. The average rate
of dip has not been determined.

Topographic Features

In traveling east from Laredo, it is to be noted that for several
miles, after crossing Chacon Creek, the country is characterized

Notes on Oil and Gas Fields of Webb and Zapata Counties 1

TORCCILLAS !

----. cole Petroleum **1

^

MAP OF

WEBB AND ZAPATA COUNTY
OIL FIELDS-
SCALE

• •• / 5TARR CO.

8 University of Texas Bulletin

by successive minor ridges which trend, in general, north-south.
These ridges have a rather abrupt west face and represent west
facing escarpments, marking the outcropping edges of east
dipping strata. In some instances the escarpments are held up
by a hard stratum consisting chiefly of oyster shell rock. About
eleven miles east of Laredo the land becomes more nearly level.
Just east of Mirando City is the pronounced Keynosa escarp-
ment to which reference has already been made.

Location of the Oil md Gas Fields with Respect to the
Topographic Features

The Charco-Redondo and Jennings fields are located in or
near the belt of country referred to above as probably repre-
senting the Fayette formation. Each of these localities is
some distance from the Reynosa escarpment, the Charco-Redondo
locality being possibly seven miles, and- the Jennings field prob-
ably not quite so far. The Reiser gas field is likewise seven
or eight miles west of the Reynosa escarpment. On the other
hand, the Mirando and Schott pools and the gas wells of the
Carolina-Texas Company are located immediately at the foot
of this escarpment.1

Charco-Redondo Wells

The Charco-Redondo oil wells are located in the southeastern
part of Zapata County. The wells, now producing, are shal-
low, varying from 135 to 160 feet in depth. The oil is from
sands and sandy shales, slightly greenish in color, found asso-
ciated with, and usually underlying an oyster shell stratum,
which serves as cap-rock. About twenty-one wells have been
drilled, of which sixteen are now being pumped, the produc-
tion being from one to three barrels per day per well.

The oil sand at this locality dips to the east. Thus the west-
ernmost of the wells obtain production at a depth of from 135
to 140 feet, while wells farther to the east on land of equal
or lower elevation find the oil sand at from 150 to 160 feet.
About one mile west of the oil wells there is a west facing

gas wells more recently obtained by the Carolina-Texas
Company one is reported to be located on the escarpment.

Notes on Oil and Gets Fields of Webb and Zapata Counties 9

scarp held up by an oyster shell stratum. This oyster shell
bed is probably the same as that associated with the oil sand,
indicating the eastward dip in the formations.

The producing sands at this locality are probably in the Fay-
ette formation. The oil has a gravity of about 18.5 B, and is
said to yield a good quality of lubricating oil.

The Jennings Gas Field

The Jennings Gas Field is located in the northeastern part of
Zapata County, about seven miles from the east and nine miles
from the north county line. This field was discovered in 1914
when a test well for water obtained gas. Ten or more wells
have been drilled. Two of these, failing to obtain gas, were
drilled to a greater depth and obtained fresh water at about
1900 feet. The yield in the gas wells is said to be, for each
successful well, between ten and twelve million cubic feet initial.

Surface exposures of the light colored slightly sandy rock with
strata of volcanic ash provisionally referred to the Fayette
formation were observed four or five miles northwest of the
Jennings Field. No exposures were seen immediately within
the gas fields, but it is probable that the surface formation at
this locality is Fayette. The gas horizon at this locality lies
between 1200 and 1300 feet below the surface. It seems prob-
able that the gas horizon is within the Yegua formation, although
formation thicknesses at this locality are not fully determined.

The Mirando Pool

The Mirando Pool is located in the northeastern part of Zapata
County, about two miles from the east and three from the
north county line. The discovery well in this field was com-
pleted' in the spring of 1921. Since that time drilling has
been actively continued in this field. These wells are located
at the foot of the Reynosa escarpment, and at a place where,
as indicated on the sketch map, the escarpment bends abruptly
to the east.

The producing sands in this field lie at a depth approximating
1450 feet from the surface. The wells are about seven miles

10 University of Texas Bulletin

north and five miles east of the Jennings gas pool. Since the
regional dip is to the east, if the gas at Jennings is from the
Yegua, it seems probable that the oil at Mirando Pool is like-
wise from this formation. On this point, however, the evidence
is at present inconclusive. The logs of the deep wells in and
near this pool indicate that sandstones are entered at about
1700 feet.

The wells at the west edge of the Mirando Pool produce gas,
while in the central part of the pool the wells yield oil with
but little gas. The oil is from 21.5 B gravity, and is said to
contain very little gasoline.

The Reiser Gas Field

The Reiser Gas Field, in Webb County, is located on and
near the Texas-Mexican Railway, twenty-five miles east of
Laredo. About twelve gas wells have been obtained at this;
locality, the best of which are reported to have made twenty or
twenty-five million cubic feet of gas per day. Formerly the
gas from this field supplied Laredo, but is used at the present
time only for local purposes.

The chief gas horizon at Reister is found at a depth of from
650 to 800 feet. Probably the gas in this field is obtained from
the Yegua formation, although, as in the case of the other fields
in this area, the age of the producing horizon cannot be regarded
as definitely determined.

The Schott Pool

The Schott Pool is located about thirty-five miles east of
Laredo, and one and one-half miles south of Mirando City.
The discovery well in this field was completed December, 1921.
This pool is located near the foot of the Reynosa escarpment.
The country is somewhat rolling, and there are occasional hills
remaining as outliers or remnants of the Reynosa formation.

The producing horizon of the Schott Pool is found at a depth
of from 1525 to 1550 feet. About three miles southwest of
this pool are exposures which appear to represent the Fayette
formation from which it seems probable that the wells of the-

Notes on Oil and Gas Fields of Webb and Zapata Counties 11

Schott Pool, like those of the Mirando Pool, start near the top
of the Eocene. Production in the Schott Pool is being obtained
from seventy-five to one hundred feet deeper than in the
Mirando Pool, the surface elevation being essentially the same.
Whether or not production in the Schott Pool is from the
same horizon as in the Mirando Pool is undetermined at this
time. At Mirando City, some oil has been obtained at a depth
of about 1630 feet.

A well located about three-fourths of a mile northwest of the
Schott Pool apparently passed- the oil producing horizon at
about 1635 feet. This well continuing to a greater depth en-
countered a thick body of slightly sandy, blue and pink some-
what calcareous shale which was penetrated to a depth of 2500
feet, where sandstones were encountered.

In the Schott Pool as in the Mirando Pool, gas is found in
wells west of those producing oil, apparently marking the west
margin of the pool. The producing sands as indicated by the
wells dips to the east with possibly a structural nose. The oil
of the Schott Pool appears to be very similar in character to
that of the Mirando Pool. The well of the Kanoka Oil Com-
pany in the Schott Pool, after being cleaned, produced not
less than 800 barrels per day.

The Carolina-Texas Oil Company Gas Wells

The Carolina-Texas Oil Company has a well from which gas
has been obtained, located about seven miles east of north of
Torrecillas. This well is at the foot of the Reynosa escarpment,
and at a place where a small stream enters from the highland,
forming a reentrant in the margin of the scarp.

Some gas was obtained in this well at 1295 feet, but the prin-
cipal gas horizon is reported at a depth of 2015 feet, The for-
mation from which the gas is obtained is undetermined. This
well is about ten miles north and four miles east of the Schott
Pool. A second well drilled at this locality obtained some gas
at 1296 feet.1

3Two additional wells drilled since this manuscript was submitted
and located east of the first two wells are reported to have obtained
gas.

12

University of Texas Bulletin
Well Records

A summary of representative wells in these two counties is
given in the table which follows. In addition a number of logs
are included indicating the drilling conditions in the several
fields.

Summary of Representative Wells in "Webb and Zapata Counties

Name of Well.

Location. Depth.

Remarks .

Oarolina-Texas Oil Co._

Surv. 268, 7 miles N.
N. E. of Torrecillas

2015

Gas show at 1270-1279. Gas
at 2015.

Zapata Oil and Gas Oo.

Charco Redondo

1735

Oil sand at 163-168. Gas
show in sand at 932-965.

Texas Company.
Jennings No 4

Jennings Gas Field.

1% mi. N. W. of Ranch
House

3015
1367?

1234?

Fresh water at 196tf.

12 M gas at 1265-1357. Rock
pressure 455 Ibs.

9 M gas at 1229-1234. Rock
pressure 4<?0 ibs.

Jennings No 3

2V3 mi. N. E. of Ranch
House -

Cuellor No. 1 . — — -

U£ mi. E. N. E. of
Ranch House

Tveeton Synd. No. 2

Mirando Oil Co. No. 2_
Mirando Oil Co. No. 3.
.Mirando Oil Co. No. 4a
Mirando Oil Co. No. 7-

Witherspoon Oil Co.
No 4

Mirando Pool.

N. W. pt. of pool. Blk.
23

1467
1502
1426
1453

1490

2000
1460

1476
1730

Gas at 1445-1467.
Show of oil at 1447-1452.
Producer. Discovery Well.
Oil sand at 1433-1442.

Oil sand 1470-1476. 100 bbls.
Sandrock 1735-2000.
Reported producing. 80 bbls.

Gas well, sand 1443-145-"..
Reported dry.

S. pt. of pool. Blk. 5__
S. pt. of pool. Blk. 5__
S. pt. of pool. Blk. 5-
Central pt. of pool. Blk.
17

N. pt. of pool. Blk. 18.
Central part of pool

Witherspoon Oil Oo.
No 1

Tenn-Zapata Oil Co.
No 1

S. W. pt. of pool. Blk.
16

Zapata Red. & Ref.
Oo

Surv. 113. S. of pool

Producers Oil Com-
pany.
B. & M. No. 5 (Com-
pleted by Brethwith
& Allison)

Reiser Gas Field.
Near Reiser

2598

j 2240
€85

Water at about 1800 ft.
Sands 200 ft. from surf.
Gas reported at 2500 ft.
Mineral water at 1500±.
Gas in use for local supply.

Reiser No. 1 ._

1 mi E. of Reiser

RiCiser No 4

Af P/iiocir

Notes on Oil and Gas Fields of Webb and Zapata Counties 13

Summary of Representative Wells in Webb and Zapata Counties — Continued

Name of Well.

Location.

Depth.

Remarks.

Kanoka Oil Co. No. 1.

Schott Pool.

N. Central pt. of pool.
Blk. 6—

1559

Oil sand at 1545-1559. Re-

Laurel Oil Oo. No. 1— _
Leaseholders Oil Co.
No 1

W. pt. of pool. Blk. 9.
W. pt. of pool. Blk. 10

1539
1599

portted making1 800 bbls.
per day.
Gas well.

Gas well.

Schott Oil Co. No. 2..

Central pt. of pool. Blk.

11

1532

Gas and oil at 1530-1532

Sehott Oil Co. No. 3—
Schott Oil Co. No. 1—

South Plains Oil & Gas
Co.

E. part of pool. Blk. 12
West of pool. Sur. 462_-

N. W. of pool. Sur. 460

1588
1750

2500

Oil at 1571-1588.
Ends in red and blue shale
and gumbo.

Below 1600 chiefly red and

Laredo Oil Co. No. 2—

In Mirando City - —

1635

blue shales.
Oil at about 1635.

Well Logs in Webb County

The following logs of wells in Webb County are arranged
alphabetically according to owners of the land on which the
wells are located, and the company owning the well.

tog- of Albercas No. 1, Albercas Oil Co., Survey 836, About Three Miles
North Slig-htly West of the Mirando Pool

Depth in Feet.

From.

To.

ness.

Red sandy clay _

0

42

42

Blue clay and boulders

42

79

37

Shale

79

132

53

Gumbo - - — -

132

142

10

Shale and boulders _ _.

142

163

21

Green ''hale and boulders

163

246

83

Lime rock

246

250

4

Hard sandy shale

250

281

31

Blue and green gumbo and shale

281

410

129

Hard gummy shale - -

410

506

93

Shale and boulders -

506

613

107

Water sand

613

671

58

Gumbo

671

710

3f)

Gummy shale and boulders _

710

778

68

Shale and sand, oil showing.

778

789

11

Hard shale .. -— -

789

S40

51

Packed sand

840

871

31

871

961

90

961

092

31

992

1,055

63:

1,055

1,142

87

1,142

1,172

30

Shale and! boulders - «

1,172

1,280

108

Hard sandy shale...

1,280

1,309

23

University of Texas Bulletin

Log- of Albercas No. i, Albercas Oil Co., Survey 836, About Three Miles
North Slig-htly West of the Mirando Pool— ^Continued

Depth in Feet.

Thick-
ness.

j
From. 1 To.

Gumbo

1,309
1,318
1,445
1,480
1,491
1,505
1,507
1,548
1,550
1,559
1,585
1,€61
1,684
1,709
1,720

1,727
1,734
1,739

1,318
1,445
1,489
1,491
1,505
1,507
1,548
1,550
1,559
1,535
1,601
1,684
1,709
1,720
1,727

1,734
1,739
1,797

9
127
44
2
14

9

4i

9
26
76
23
25
11
7

7
5
58

Hard and soft shale, blue and brown _

Shale and boulders

^Packed sand

Hard shale

Lime rock

Hard shale, pyrites and boulders __

Ifime rock _.

'Gumbo - _

Xhale and boulders --

Hard gumbo - --

Hard shale

Hard shale and boulders -

Hard sand rock, showing gas.

Soft "ind -

Hard shale total depth

Began December 7, 1921; completed February 11, 1922; set 8", casing at 743'; set 6* cas-
ing at 1735'; 1 ft. in reck. 8" casing leftt in hole and derrick left standing with inten-
tion of drilling deeper.

Log- of Barusly No. 1. Carolina Texas Oil Co. Survey 268, About Pour
Miles Northeast of Mirando City

Depthi

n Feet.

Thick-

From.

To.

ness.

Clay

a

22

Rock -

22

48

26

Sand

56

8

Rock

56

59

3

Shale — —

59

72

13

Sand

72

77

5

77

103

26

Rock

103

108

5

108

141

' 1

Rock --

141

142

1

Sand _

142

160

18

Rock

160

162

»)

162

195

33

Rock

195

197

2

197

217

20

217

220

3

Sand

228

8

Rock

228

229

1

Sandy shale _____

229

254

25

254

260

6

Sand _

260

270

10

Sand and boulders -

270

310

40

Rock -

310

312

2

Sand boulders

312

375

63

Rock

375

380

5

380

402

22

Gumbo -

402

407

5

407

428

21

Pay .

428

435

435

440

5

Snnrl and boulders

440

460

20

Notes on Oil and Gas Fields of Webb and Zapata Counties 15

Log- of Barusly No. 1. Carolina Texas Oil Co. ssurvey 268, About FOur
Miles Northeast of Mirando City — Continued

Depth in Feet.

Thick-
ness.

From.

To.

Bock _ — _.

460

464
610
616
630
760
764
780
796
827
835
910
916
930
970
1,000
1,002
1,060
1,065
1,070
1,085
1,088
1,130
1,135
1,137
1,155
1,168
1,195
1,222
1,226
1,270
1,295

1,401
1,466
1,535
1,550
1,568
1,573
1,600
1,608
1,654
1,685
1,700
1,725
1,732
1,800
1,815
1,827

464
610
616
630
760
764
780
796
827
835
910
916
930
970
1,000
1,002
1,060
1,065
1,070
1,085
1,088
1,130
1,135
1,137
1,155
1,168
1,195
1,222
1,226
1,270
1,295
1,322

1,466
1,535
1,550
1,568
1,573
1,600
1,608
1,654
1,685
1,700
1,725
1,732
1,800
1,815
1,827
1,995

4
146
6
14
130
4
16
16
31
8
75
6
14
40
30
2
58
5
5
15
3
42
5
2
18
13
27
27
4
44
25
27

65
69
15
18
5
27
8
46
31
15
25
7
68
15
12
168

Sandv shale and boulders

Gumbo —

Water sand _ _

Pink gumbo -

Sand and boulders _> - - — -

Gas sand -- >

Sand and boulders -

Pay sand - - -- - — — -

Sand and boulders - - - —

Bock _

Sand _

Rock -

Gumbo -

Pfl V

Clay (?) - -

No log 1,322 to 1,401. This well deepened by Trussle, Brown
& Hodges.
Sandy shale -

Shale and boulders - -- - —

Sand

Shale and boulders - --

Shale

Hard shale -- -~ - -

Shale -

Shale

Total depth, 2,015. Shale grades into sandy shale and apparently into a coarse
grained sandstone, which is producing aboutl 8 M cu. ft. gas.

16

University of Texas Bulletin

Log- of Breckenridse No. 1, South Plains Oil & Gas Co., Survey No. 460,

Southeast Corner of Block 15, About One Mile

Southwest of Mirando City

Depth in Feet.

Thick-
ness.

From.

To.

Surface clay

0
20
72
120
122
240
261
272
349
400
422
428
451
471
474
487
620
628
670
680

%

772
815
830
882
892
905
940
951
958
998
997
1,040
1,060
1,135
1,155
1,160
1,212
1,219
1,282
1,286
1,327
1,331
1,348
1,393
1,426
1,441
1,444
1,460
1,470
1,488
1,498
1,502
1,506
1,509
1,547
1,556
1,579
1,595
1,603
1,604

20
72
120
122
240
261
272
349
400
422
428
451
471
474
487
620
623
670
680
710
771
772
815
830
882
892
905
940
951
958
993
997
1,040
1,060
1,135
1,155
1,160
1,212
1,219
1,282
1,286
1,327
1,331
1,348
1,393
1,426
1,441
1,444
1,460
1,470
1,488
1,498
1,502
1,506
1,509
1,547
1,556
1,579
1,595
1,603
1,604
1,685

20
52
48
2
118
21
11
77
51
22
6
23
20
3
1?
133
3
47
10
30
61
1
43
15
52
10
13
35
11
7
35
4
43
20
75
20
5
52
T
63
4
41
4
17
45
33
15
3
16
10
18
10
4
4
3
38
9
23
16
8
1
31

Yellow clay and boulders--

Bed clay and shale

Lime rock

Hard shale and boulders..

Gumbo -

Lime rock

Hard green shale and bou
Shale —

Iders

Chalk rock ..

Gumbo

Shale

Packed sand

Hardi lime rock _.

Gumbo

Soft gummy shale

Soap stone

Soft shale

Gumbo -

Hard shale _.

Lime rock-

Shale and boulders

Gumbo

Hard shale

Sand rock

Soft lime rock

Shale and boulders

Hard ilme rock

Gumbo

Soft shale

Sand rock

Hard sandy shale

Water sand - - —

Hard shale

Sandy shale

Gumbo

Soft shale

Gumbo

Hard sandy shale and bou
Lime rock

Iders

Hard shale and streaks- of
Sand rock

gumbo

Sandy shale

Gumbo

Hard shale and boulders -

Sandy shale

Soft shale

Hard gummy shale
Shale and boulders

Hard sandy shale

Soft sandy shale; set 8" p
Shell rock _.

ipe

Sand _

Notes on Oil and Gas Fields of Webb and Zapata Counties 17

log- of Breckenridg-e No. 1, South Plains Oil & Gas Co., Survey NO. 46O,

Southeast Corner of Block 15, About One Mile

Southwest of Mirando City — Continued

Depth in Feet.

mK}«-i,

From.

ness.
To.

Sandy shale; set liner and bs
Shale

iled

1,635
1,641
1,660
1,665
1,725
1,731
1,741
1,747
1,751
1,784
1,785
1,831
1,860
1,866
1,947
1,957
1,872
1,998
2,004
2,015
2,021
2,036

1,641 6
1,660 19
1,665 5
1,725 60
1,731 6
1,741 10
1,747 6
1,751 4
1,784 33
1,785 1
1,831 46
1,860 29
1,866 6
1,947 81
1,957 10
1,972 15
1,998 26
2,004 6
2,015 11
2,021 6
2,036; 15
2,055; 19
2,060! 5
2,061 1
2,067, 6
2,100 33
2,106! 6
2,128 22
2,176 43
2,180 4
2,186 6
2,195 9
2,202: 7
2,240! 38
2,300 60
2,360| 63
2,405 45
2,475! 70
2,476 1
2,480 4
2,500 20
2,527: 27
2,540 13
2,542[ 2
2,550, 8
2,562 12
2,578! 16
2,588 10
2,591 3
2,603 12
2,623 20
2,630 7
2,665 35
2,689| 24
2,6X>! 1
2,709 19
2,726 17
2,746 20
2,775 29
2,8021 27
2,807; 5
1 fflfi Q

Gumbo -

Green shale

Gumbo

Packed sand

Shale

Gumbo

Hard blue shale

Pink shale

Green shale, soft and hard j
Pink shale and lime streaks

streaks

Blue gumbo

Pink shale with streaks of gi
Gyp gumbo

imbo

Hard pink shale

Blue shale.

Gumbo _ .

Pink shale __.

Gumbo -

Hard blue shale

Blue gumbo -

2,055
2,060
2,061
2,067
2,100
2,106
2,128
2,176
2,180
2,186
2,195

Lime rock

Gyp gumbo __.

Blue shale

Blue shale

Hard pink shale

Gyp gumbo1

Sand -

Sand and shale streaks

Hard gummy shale-. _.

Green shale and boulders

2,202
2,240
2,300

Blue shale soft and gummy-

Green shale_- --

Blue and pink shale

2,3€0
2,405

2,475

Pink shale

Soft lime rock

Gumbo

2,476
2,480
2,500
2,527
2,540
2,542

Hard shale and lime streaks
Not recorded

Sand shale

Sand and shale streaks

Dry sand, gas show-

Hard sand and boulders gas
Hard shale and shells

show

2,550
2,562
2,578
2,588
2,591
2,603
2,623
2,630
2,665
2,689
2,690
2,709
2,726
2,746
2,775
2,802
9 R07

Gumbo

Sand

Pink shale and boulders

Hard shale and sand streaks
Gumbo

Hard pink gummy shale

Pink and blue shale

Rock and pyrites _ ~

Blue slate shale

Soft shale and sand streaks
Sulphur water sand

Hard sand

Soft shale and sand streaks
Hard sand

Blue shale

Shale and boulders.— .

2,816 2,8591 43

18

University of Texas Bulletin

Log- of Breckenridg-e No. 1, South Plains Oil & Gas Co., Survey No. 460,

Southeast Corner of Block 15, About One Mile

Southwest of Mirando City—Continued

•

Depth i

n Feet.

Thick-

From.

To.

ness.

Hard sand gas showing ... _ '

2 859

2 879

20

Hard sand

2 879

2 885

g

Hard sand gas showing-

2 885

2 900

15

Hard sand

2 900

2 928

28

Sulphud water sand

2 928

o 940

1°

Shale and boulders

2,940

2 980

40

Shale and gumbo

2 960

3 009

29

Log- of l-olts No. 1, Santa Maria de los Angeles Surrey, About One-half
Miles East of Bruni, In Eastern Fart of Webb County

From.

To.

ness.

Soil _. __

0

5

5

Sand and clay

5

10

5

10

50

40

Hard sand

50

75

25

Lime rock

75

105

30

Gravel and water sand

105

115

10

Sandy shale

115

175

60

Water sand

175

225

50

Hard shale

225

325

100

Gumbo

325

400

75

Blue shale

400

525

125

Water sand _

525

625

100

Blue shale

625

800

175

Gummy red shale

800

1 000

20ft

Blue shale

1 000

1 100

100

Gummy red shale

100

1 200

100

Black shale

,200

1,300

100

Hard blue shale

,300

1,400

100

Gumbo

400

1 475

75

Hard sandy shale____________ ___________
Soft blue shale

Gas sand- _ __ ___•__ ___ ___

,475
,500
600

1,500
1,600
1 625

25
100

25

Hard black shale _

'_H-r

1,700

75

Sea shell

1 700

1 705

5

Sandy shale
Sea shell _ '. ' I

1,705
1 790

1,790
1,800

85
10

Soft sandy shale __ _

1,800

1,810

10

Depth in Feet.

Casing set at 1,875 in cement; 4%" lines set at 1,650.

Hole was bailed dry, making quite a bit of gas; pulled lines and finished hole at
1,810', with no oil showing.

Notes on OH and Gas Fields of Well) and Zapata Counties 19

Of Xanola. No. l, Survey 54, About One and One-half Miles South of
Uirautto City. After Cleaning- Well Produced 80O totals, or
More. Discovery Well of the Schott Pool

Depth in Feet.

From. To.

Thick-
ness.

Surface soil

Yellow clay

Soft Time clay

Loose gray shale

Red and blue shale •

Water sand

Fine blue sand —

Red mixed shale 150

Hard red clay 210

Red mixed shale -

Soft lime clay

Red mixed shale -- 274 296

Blue shale ^ 296 320

Gummy shale 320

Red and blue shale 373

Hard gummy shale 373

Gumbo 399 411

Soft lime rock 411 420

Red and blue shale 420 448

Hard lime rock - 448 453

Red and blue shale. 453 512

Hard lime rock 512

Hard blue shale and lime — 522

Hard gummy shale 601 622

Lime rock 622 635

Red and blue shale €35

Lime rock 660 672

Hard blue shale 072

Lime rock 700 776

Red and blue shale 776 844

Lime rock

Red and blue shale__, 860 940

Lime rock — 940 978

Red and blue shale 978 1,000

Lime rock 1,000 1,023

Red and blue shale 1,023 1,073

Gumbo 1,073 1,

Lime rock 1,084 1,102

Gumbo — 1,102 1,114

Hard gummy shale 1,114 1,129

Red and blue shale __ 1,129 1,140

Lime rock 1,140 1,162

Hard gummy shale __, 1,162 1,184

Gumbo, 1,184 l.

Red and blue shale _ 1,196 1,216

Gumbo 1,216 1,227

Lime rock ^ 1,227 1,248

Gummy shale 1,248 1,271

Lime rock_ _.. . 1,271 1,282

Gumbo - 1,282 1,293

Red and blue shale ___ 1,293 1,304

Gumbo - 1,304 1,313

Lime rock and shale 1,313 1,328

Red and blue shale 1,328 1,350

Lime rock — 1,350 1,

Hard blue shale 1,362 1,374

Red and blue shale 1,374 1,

Lime rock 1,396 1,406

Hard blue shale. — - 1,406 1,440

Lime rock 1,440 1,462

Hard blue shale — 1,462 1,499

Lime rock (gas big) 1,499 1,508

Hard blue shale 1,508 1,513

Hard lime rock (gray sand) set casing 1515' 1,513 1,515

20

University of Texas Bulletin

tog- of Xanoka No. 1, Survey 54, About One and One-half Miles South of

MiraJido City. After Cleaning1 Well Produced 800 btols. or

More. Discovery Well of the Schott Pool — Continued

••

Depth in Feet.

Thick-
ness.

From.

To.

Xiime rock-

1,515
1,517
1,522
1,523
1,533
1,537
1,543
1,545

1,517
1,522
1,523
1,533
1,537
1,543
1,545
1,569

2
5
1
10
4
6
2
14

Shells and
Sand rock.

shale__ _

Shale and
Gumbo -—

sand -

Shells and
Hard lime
Hard sand

shale

rock

(heavy oil sand)

Stopped in gumbo.
Set casing" in cement.
Set 6&, 7".

Log- of Laredo Oil Co., Well No. 1, Survey 458, in Mirando City

Depth in Feet.

Thick-
ness.

From.

To.

Surface _ .

0
10
18
20
35
45
61
62
76
86
96
101
115
133
148
179
184
194
205
213
231
246
256
284
294
304
330
344
360
375
385
393
413
414
434
454
460
480
510
525
533
555

10
18
20
35
45
61
62
76
86
96
101
115
133
148
179
184
194
205
213
231
246
256
284
294
304
330
344
360
375
\ 385
! 393
413
i 414
434
454
460
480
510
525
533
555
587

10
8
2
15
10
16
1
14
10
10

»!

18
15
31
5
10
11
8
18
15
10
28
10
10
26
14
16
15
10
8
20
1
20
20
6
20
30
15
8
22
32

White lime and sand ... ...

Gravel _

Sand

•Clay' _.

Sand, clay and shell

Pink shale __

".Red clay _i __

-•Gray shale .

Blue and gray shale _

White lime rock

•Gray shale

Pink gumbo

Blue snale

(Gray gumbo

]Brown shale

Blue shale _ _

Gray shale

Hard shale

Shale

Sandy shale

Blue gumbo -

Brown gumbo

Blue gumbo -

ROCk

Gray shale

Grnv erumbo

Notes on Oil and Gas Fields of Webb and Zapata Counties 21

Log- of Laredo Oil Co., Well No. l, Survey 458, in Mirando City — Continued

Depth in Feet.

Thick-
ness.

From.

To.

Slate with coal

587
615
654
656
664
715
759
760
778
800
816
824
825
875
883
905
920
952
960
972
978
1,014
1,029
1,039
1,049
1,059
1,076
1,084
1,089
1,092
1,114
1,146
1,165
1,185
1,215
1,230
1,260
1,275
1,285
1,291
1,321
1,341
1,411
1,431
1,446
1,466
1,496
1,521
1,531
1,56]
1,581
1,621
1,6&
1,«6C
1,654
1,665

615

654
656
664
715
759
760
778
800
816
824
825
875
883
905
920
952
960
972

28
39
2
8
51
44
1
18
22
16
8
1
50
8
22
15
32
8
12
6
86
15
10
10
10
17
8
5

22
32
19
20
30
15
30
15
10
6
30
20
70
20
15
20
30
25
10
30
20
40
15
14
4
• 8

Rock _

White lime rock - ---

day shale - --

Rock _

Gray shale - - - -

Brown shale -- - -

978
1,014
1,029
1,039
1,049
1,059
1,076
1,084
1,089
1,092
1,114
1,146
1,165
1,185
1,215
1,230
1,260
1,275
1,285
1,291
1,321
1,341
1,411
1,431
1,44€
1,4«
1,49*
1,521
1,531
1,561
1,58]
1,62]
1,63(

i,ea

1,65^
1,661

Blue shale - -

Blue gumbo -

Blue gumbo -

Shale -

Lime rock -

Shale and gumbo -- --

Shale

Soft lime rock

•Gumbo

Blue shale - -

Shale

Gumbo

Shale - --

<§hale -

Shale

Rock -- - — -

This well gave a flow of oil when first drilled. Subsequently abandoned on account
of water trouble.

22

University of Texas Bulletin

log- of Well On Reiser Hanch, Producers Oil Co., B. & M. Lease Well No. 5r

Survey 1617, About One-fourth Mile South of Reiser's

Station. Total Depth 2,598

s

Depth j

n Feet.

Thick

From.

To.

ness.

Surface sand

0

3

3

Sandy red clay

3

g

3

Brown sand __ __

6

12

6

Gravel with some salty water

12

14

o

Brown shale __

14

45

31

Sandy yellow clay

45

58

13

Brown shale

58

110

59

Sand

110

118

8

Shale

118

126

g

Shale

126

164

35

Gumbo

164

170

6

Shale

170

208

38

Lime shells with some sand

208

220

12

Red clay __

220

286

63

Sand salt water

286

992

6

Shale black

292

334

4->

Sand

334

339

5

Sandy shale

339

404

65*

Gumbo

404

413

9

Shale black

413

476

(>3

Sand

476

482

G

Shale

482

564

82

Gumbo

564

570

6

Brown shale

570

642

79

Sand, gas show

642

649

y

Black shale

fi49

674

25

Gumbo

674

686

12

Red clay

686

793

107"

Sand

79S

798

5

Shale with sand shell . — — ._ —

798

885

87

Sandy shale - _ _ ____

885

914

29

Gray salt sand

914

926

12

Brown shale

926

938

12

Sand

938

945

Shale with sand

945

987

49

Sandy shale --

987

1,032

45

Blue shale sand shells, iron

1,032

1,116

84

Gumbo - -

1,116

1,123

7

Sand

1,123

1,138

15

Sandy blue shale J_

1,138

1,184

46

Sand - -- - -- —

1,184

1,192

8

Black shale _ _. _

1,192

1,203

16

Sand

1,208

1,227

19

1,227

1,243

21

1,248

1,285

37

1,285

1,312

27

Shale

1,312

1,324

12

Sand

1,324

1,332

8

Sand set 8"

1,332

1,369

37"

This well is said to have been subsequently drilled to a depth of 2,598 feet. Water-
was obtained at about 1,800 feet, and gasi is reported at about 2,500 feet.

Notes on Oil and Gas Fields of Webb and Zapata Counties 23

Log- of Garcia No. 2, Schott Oil Co., Survey 54, About One and One-half

Miles South of Mirando City. Gas and Oil Well, Initial

Production Oil Reported at 74 tobls.

Depth in Feet.

Thick-
ness.

From.

To.

Yellow sand

0
2
10
30
57
107
135
168
165
220
260
290
330
342
475
490
587
563
600
637
670
673
€&5
687
700
745
750
800
805
861
873
897
900
918
937
960
968
1,000
1,020
1,067
1,083
1,100
1,115
1,160
1,187
1,193
1,213
1,237
1,275
1,297
1,317
1,350
1,357
1,384
1,400
1,410
1,427
1,449
1,467
1,482
1,500
1,510
1,515
1..523
1,527
1,530

2

10
30
57
107
135
163
165
220
260
290
330
342
475
490
537
563
600
637
670
673
685
687
700
745
750
800
805
861
873
897
900
918
937
960
983
1,000
1,020
1,067
1,083
1,100
1,115
1,160
1,187
1,193
1,213
1,237
1,275
1,297
1,317
1,350
1,357
1,384
1,400
1,410
1,427
1,449
1,467
1,482
1,500
1,510
1,515
1,523
1,527
1,530
1,532

2
8
20
27
50
28
28
2
55
40
30
40
12
138
15
47
26
37
37
33
3
12
2
13
45
5
50
5
56
12
24
3
18
19
28
23
17
20
47
16
17
15
45
27
6
20
24
38
22
20
33
7
27
16
10
17
22
18
15
18
10
5
8
4
3
2

Soft limA clay -- -- -

Yellow clay

Blue shale

R£d clay

Soft lime rock

Hard blue shale

Lime rock

Hard blue shale

Blue shale and sand

Gumbo

Blue shale __ _ ._

Red and blue shale

Blue shale and sand

Soft lime rock

Hard blue shale and sand

Lime rock-- _ --

Tough gumbo

Lime rock

Gumbo

Lime rock _ _- __ __

Gumbo

Lime rock

Gumbo - -

Hard blue shale __

Lime rock

Red and blue shale

Soft lime rock -_ _

R«d and blue shale

Lime rock__

Gumbo

Blue shale

Lime rock

Gumbo -_

Blue shale and sand

Tough gumbo

Soft rock _ — __

Hard blue shale

Gumbo

Lime rock

Red and blue shale __

Gumbo

Lime rock

Hard blue shale -

Lime rock__ .

Hard blue shale

Gumbo

Lime rock _ _ __

Gumbo _. _

Hard blue shale

Lime rock

Gumbo -

Hard blue shale—

Lime rock

Blue shale

Soft blue mud

Soft lime rock

Red and blue shale

Soft lime rock „

Hard lime rock

Tough gumbo

Hard lime rock-

Soft lime rock

Hard lime rock

Hard blue reck, sandstone __

Porous gray sand rock

University of Texas Bulletin

Log- of Urban No. 1, Bio Grande Oil & Gas Co., Survey 7; Ten or Twelve

Miles North of Laredo

Depth i

n Feet.

Th ick-

Prom.

To.

ness.

Yellow clay

0

18

118

White shale

18

30

12

Blue shale

30

30

Pink shale _ - __

60

80

20

Sand

80

Of)

10

Blue shale

90

260

170

Cave __

260

265

5

Blue shale

265

290

25

Cave _ —

290

295

5

Blue shale

295

360

65

Cave

360

365

5

Blue shale _ _

365

545

180

Sand, showing of oil

545

553

8

Blue shale .

553

633

80

Slate

633

800

167

Water sand

800

881

81

Shale

881

860

70

Sand

960

1 000

40

Slate _.

1 000

1 006

(j

Sand

1,006

1,058

52

Slate

1 058

1 075

17

Sand _ -

1 075

1,093

18

Water sand

1 033

1 103

10

Slate

1 103

1 122

19

Sand

1,122

1,140

19

Slate - — —

1,140

1,145

Sand

1 145

1 ?10

65

Slate

1,910

1,220

10

Sand

1,220

1 255

35

Slate

1 255

1 263

g

Sand -

1 263

1,320

57

Sand _- _ _-

1,320

1,340

2o

Water* sand

1,340

1,366

25

Brown shale

1,365

1,369

4

Sand

1,369

1,400

31

Slate

1,400

1,404

4

Sand began underreaming' 1,130'

1 404

1,450

46

Red rock

1,450

1 455

Sand --

1,455

1 470

15

Red rock i __

1,470

1,472

2

Sand

1 472

1,515

43

Broken formation, sand, slate, red rock _

1,515

1,580

65

Sand

1 580

1 600

9Q

Casing record: Set 12y2", casing at 553'; 10" at 1,058'.

Log Wells in Zapaita County

Log- of Hinnant No. 6, Mirando Oil Co., Survey 114, Block 5, Lot 1,
Initial Production 150 btols., Mirando Pool

Depth i

n Feet.

Thick-

Prom.

To.

ness.

Clay and gravel

0

98

93

Pack sand

98

100

2

Blue shale -

100

140

40

Hard shale

140

150

10

Shale and sand

150

170

20

Shale

170

360

190

Boulders _.

360

371

n

Notes on Oil and Gas Fields of Webb and Zapata Counties 25

of Hinnant No. 6, Mirando Oil Co., Survey 114, Block 5, Lot 1,
initial Production 15CKJ bbls., Mirando Pool — Continued

Depth in Feet.

Thick-
ness.

From.

To.

Shale

371
590
600
638
641
658
665
720
725
815
826
857
860
863
1,040
1,059
1,099
1,108
1,123
1,167
1,231
1,257
1,320
1,384
1,401
1,412
1,425
1,431
1,448
1,462

590
600
638
641
658
665
720
725
815
826
857
860
863
1,040
1,059
1,099
1,108
1,123
1,167
1,231
1,257
1,320
1,384
1,401
1,412
1,425
1,431
1,448
1,462
1,467

219
10
38
3
17
7
53
5
90
11
31
3
3
177
19
40
9
15
44
64
26
63
64
17

3

6
17
14

5

Gumbo

Shale

Sandy shale

Shale

Boulders a

Shale

Boulders

Hard sandy shale _ .

Hard red gumbo

Hard shale

Rock

Shale _ __ _— -. _

Hard shale and boulders

Green gumbo_

Hard shale

Green gumbo- -_ _

Hard shale and boulders

Blue shale

Hard shale boulders _ _

Stiff blue gumbo

Hard shale

Shale and boulders

Hard shale

Green gumbo

Pay shale and sand

Gumbo

Hard shale

Pay sand and shale _

Boulders -— --

Log- of Hinnant No. 7, Mirando Oil Co., Survey 307, Block 17, Lot 4,
Completed November 26, 1921, Mirando Pool

Depth i

n Feet.

Th i>lr

From.

To.

ness.

Clay and gravel

o

12

12

Mixed shale

12

48

33

Hard sandy shale

48

65

17

Mixed shale _ t

65

182

117

Hard shale

182

220

33

Hard shale and boulder r *_

220

273

53

Hard sand

273

275

2

Sandy shale _ « __

275

348

73

Hard sand and! boulder

348

362

14

Rock

362

365

3

Hard shale

365

385

20

Hard sand _ _ _ ____

385

387

2

Sandy shale

387

501

114

Hard shale ^- __ ....

501

545

44

545

567

22

Hard shale

567

587

20

Hard shal8 and boulder

587

704

117

Gumbo

704

710

c

Hard shale and boulder— - — - - _——-__——- - -

710

760

50

760

778

18

Hard shale and! boulder

778

840

62

Gumbo and boulder — - ____ _ __

840

865

25

865

906

41

Hard shale „

906

956

50

Gumbo

950

991

35

26

University of Texas Bulletin

of Hinnant No. 7, Mirando Oil Co., Survey 307, Block 17, lot 4,
Completed November 26, 1921, Mirando Fool — Continued

Depth in Feet.

Thick-
ness.

From.

To.

Hard shale and boulder __

991
,030
,034
,040
,071
,081
,166
,180
,252
1,290
1,S62
1,392
1,403
1,446
1,470
1.476

1,030
1,034
1,040
,071
,081
,165
,180
,252
1,290
1,362
1,392
1,403
1,446
1,470
1,476
1.490

39
4
6
31
10
84
15
72
38
72
30
11
43
24
6
14

Hard shale and boulder--

Gumbo __

Hard shale and boulder..

Boulder

Hard shale

Gumbo __ -_

Hard shale and boulder

Gumbo and boulder

Hard shale and! boulder

Hard shale

Gumbo

Shale

Gumbo _

Hard sand

Shale _.

Casing record:

>'; initial production reported at 100 bbls.

Log- of Hinnant No. 3, Witherspoon Oil Co., Surtfey 115, Block 3,
Mirando Pool

Depth i

n Feet.

Thick-

From.

To.

ness.

Red clay and gravel

0

60

60

Soft shale

60

186

126

Shale and boulders

186

336

150

Loose shale

336

520

184

Shale and boulders __

520

620

100

Gumbo

620

25

Hard gumbo

645

655

10

Shale and boulders _ _ ._

655

710

55

Gumbo . -- -

710

720

10

Hard gumbo !

720

760

40

Gumbo and gravel

760

810

50

Hard gumbo

810

840

30

Pink shale —

840

900

60

Gumbo -

900

920

20

Shale

920

940

20

Hard gumbo

940

980

40

Gumbo -

980

995

15

Pink shale — *-_

995

55

Hard sand and boulders

1,050

1*070

20

Shale anl boulders - -- — -— —

1,070

1*100

30

Gumbo and shale -

1,100

I,'l50

50

Hard gumbo - -

1,150

50

Shale

1,200

1,220

20

1,220

1 260

40

1,260

1,320

60

Hard sand and boulders

1,320

30

1,350

1,360

10

Sand and shale -

1,360

1,364

4

1,364

4

Shale -

1,368

1,375

7

1,375

1,390

15

Soft' shale -- -

1,390

1,435

45

Hard sand oil showing -- - --

1,435

1,440

5

Shale and sand—-

1,440

1,490

50

Reported producing 90 bbls. per day in April, 1922.

Notes on Oil and Gas Fields of Webb and Zapata Counties 27

Log- of

[innant No. 4, Witherspoon Oil Co., Survey 307, Block 18,
Mirando Fool; Well Abandoned

Depth i

n Feet.

Th if»lr

From.

To.

ness.

Red clay and gravel

0

60

60

Shale .__

60

180

120

Shale and boulders _ _

180

400

220

Gumbo

400

460

60

Gumbo and particles of iron

400

520

60

Boulders and shale

520

600

30

Gumbo

600

680

80

Shale and, boulders

680

760

80

Sand rock _

760

770

10

Hard' gumbo _

770

820

50

Hard sandy shale

820

860

40

Sand and boulders

860

900

40

Hard gumbo.

900

940

40

Shale and boulders

940

1 110

170

Hard shale

1 110

1 140

30

Boulders and gumbo

1 140

1 220

80

Shale and boulders-.

1 220

1 250

30

Gumbo __

1 250

1 260

10

Shale and sand upper pay

1 260

1 380

120

Hard gumbo and sand

1,380

1,435

55

Soft shale andi sand

1,435

1,445

10

Hard brown gumbo

1 445

1 450

5

Hard gumbo

1 450

1 490

40

Sand _.

1,490

1,500

10

Gumbo

1 500

1 563

63

Rock

1 563

1 565

2

Hard gumbo _ _. _

1 565

1,600

35

Sand __

1,600

1 610

10

Gumbo

1 610

1 690

89

Rock

1 690

1 692

2

Sandy shale

1 692

1,700

3

Not reeoTded

1 700

1 735

35

Hard sand rock

1 735

2*000

265

Log- of Slator No. 1, Producers Oil Co., Jose Boreffo Vosquez Grant, Within
About a Mile of North County Line; Elevation 595

Depth ]

n Feet.

ThiW

From.

To.

ness.

Soil

0

45

45

Shale

45

65

20

Sandy shale

65

84

19

Black shale _

84

208

124

Gumbo _-

208

221

13

Sand

221

230

g

Shale

230

345

115

'Gumbo --

345

395

50

Shale _

395

507

112

•Sand

507

512

5

: Shale

512

691

179

691

720

29

"Shale with iron

720

814

94

Rock white

814

820

Q

:Shale, black

820

104

284

:Sand .

1,104

,106

2

Black shale

1 106

116

10

:Sand

1 116

119

3

'Shale

1 119

291

172

1,291

400

109

Bluo shale

1,400

1,419

19

Sand -.

1.419

1.424

5

28

University of Texas Bulletin

Log1 of Slator No. 1, Producers Oil Co., Jose Boreso Vosquez Grant, Withiir
About a Mile of Nrth County Line: Elevation 596 — Continued

1

Depth in Feet.

Thick-
ness.

From.

To.

Shale — . !

1,424
1,443
1,400
1,493
1,503
1,508
1,527
1,557
1,563
1,580
1,588
1,612
1,649
1,747
1,750
1,791
1,895
1,902
1,920
1,925
1,964
1,984
2,020
2,107
2,194
2,195

j

1,443 19-
1,460 17

1,493 33

1,503 10
1,508' 5
1,527 19
1,551 30
1,563 6
1,580 17
1,588 8-
1,612 24,
1,649 37
1,747 98,
1,759 12
1,791 38
1,805 104
1,902 7
1,920 18
1,925' 5
l,964i 39
1,984 20
2,020 36
2,107i 87
2,194j 87
2,195! 1
j 2,210! 15

Shale and sand _

Sand and iron..

Shale _ —

Bock and sand

Shale _ .

Bock sand and iron (show gas 1,582-1,540)

Sulphur water, sand

Sand and iron — . -

Shale

Flinty rock and! sand

Shelly shale

Sand and iron - - -- - - -

Shale _

Shells and pyrite

Sha.le

Lime rock - - --

Shelly shale

Lime shell

Shelly shale

Slate —

Shelly shale

Shale and slate

Shale sandy

Sand

Shale, sandy - — - -

Log- of Zapata Oil & Gas Co., in ciiarco Redondo Field, Southeast Fart of
Zapata County, Yellow Clay and Sand

Depth i

n Feet.

Thick-

From.

To.

ness.

Yellow clay and sand

0

18

18-

Light green clay

18

70

52

Blue and green shale __ _

70

78

8

Boulders and slate

78

83

5

Blue clay and slate

83

163

80

Oil sand

163

168

5

Shells, fossil oysters

168

169

1

Clay and shale

169

194

25

Light blue clay

194

240

46

Shale and fossil shells - -_

240

258

18

958

<T1

13

Shells and shale

271

283

12

Bed clay

283

307

24'

Clay thin sand strata - -

307

323

16-

White clay

323

362

39

Bed clay

362

381

19

Green shale

381

390

9"

H^ird green shale -

390

438

4b

Shell and shale __

438

443

5-

Shells and shales

443

610

167

Sand and shale - -

610

619

^

Green andl blue shale - - -— - — —

619

648

29

648

662

14

Bed and green shales — - - -

662

714

52

Shells and shale — - ____________

714

760

46

Tough gumbo —

760

769

9

769

783

14

Hard slaty shale _

783

789

6

Gumbo - — - ...

789

803

14

Xotcs on Oil and Gas Fields of Webb and Zapata Counties 29

3- of Zapata Oil & Gas Co., in Charco Redondo Field, Southeast Part of
Papata County, Yellow Clay and Sand— Continued

'
Depth in Feet.

Thick-
ness.

From. To.

Hard shale and boulders
Shale and soft slate

803 807
807| 826
826 841
841 848
848 860
860 932
932 965
965! 992
992| 998
998J 1,037
1,037 1,043
1,043 1,069
1,069! 1,078
1,078! 1,118
l,118i 1,130
1,130; 1,150
1,150 1,172
1,172 1,175
1,175 1,226
1,226 1,238
l,238j 1,247
1,247 1,263
1,263 1,270
1,270! 1,286
1,286 1,298
1,298 1,302
1,302| 1,308
- 1,3081 1,329
1,329 1,341
1,341 1,347
1,347 1,5:63
1,862: 1,268

4
19
15
, 7
12
72
33
27

6
26
9
40
12
20
22

A

12

9
16
7
16
12
4
6
21
12
6
15
6
17
12
29
22
14
! 17
18

5

2
11

8
7
29
23
26
10
i 21
6
1 12

1 15
14
15
5

I

!j 11

Dull brown gumb o*

Hard sand and shells

Shale, shells and concret
Shale

ons _ _ - -

Sand and boulders, gas
Blue shale

bubbles

Sand and shale pyrite

Shale

Light green clay

Dark shale _

Gumbo -

Blue shale

Sand and green shale

Hard sandstone

Sand and shale

Harrl ga.nd,<?trmA

Shale and gumbo

Sha.le and sandstone

Gumbo _ _

Shale and shells

Black shale and pyrite

Clay

Hard dark, shale

Sand and shale

Hard sandstone

Shale

Shale and gumbo

Hard rock .

Shale and slate__

Shells —

Soft white clay

1,368 1,385
1,385 1,397
1,397 1,426
1,426 1,448
1,448 1,462
1,4621 1,479
1,479 1,497
l,497j 1,501
1,501 1,506
1,506 1,508
1,508 1,519
1,519 1,524
1,524 1,531
1,531 1,560
1,560 1,583
1,583 1,609
1,609 1,618
1,619 1,640
1,640 1,646
1,646 1,655
1,658 1,673
1,673 1,687
1,687 1,702
1,702 1,707
1,707 1,712
1,712 1,717
1,717 1,725
1,728 I,7ffl5

Shale and slate. _ .

Black shale and shells

Clay with shells

Shell rock gypsum

Shale and shells

Sand and shale

Soft white clay __ _

Hard rock concretions

Shale

Rock

*

Soft white clay

Rocks

Shale-- and clay

Shale and shells -

Clay and boulders—

White clay

Shales and clay

Rock slaty.

Rocks, concretions and
Sandstone

gypsum

White clay boulders

Shells and concretions

Sandstone slate

Rock pyrite

Gumbo

Sandstone

Shale and sand

30 University of Texas Bulletin

THE UNDERGROUND POSITION OF THE AUSTIN
FORMATION IN THE SAN ANTONIO OIL FIELDS

BY E. H. SELLARDS

The Austin formation, or Austin chalk, underlies all of the
oil fields of the San Antonio district, and is itself productive
of oil in the Alta Vista and Mission fields and perhaps to a
lesser extent elsewhere. It is a thick formation, varying from
possibly three hundred and fifty to four hundred and fifty
feet or more, consisting1 of a chalky, usually light colored or
blue rock, and with the possible exception of the Eagleford,
which lies next below it. is the most readily indentifiable for-
mation of the Upper Cretaceous series. For this reason it is
perhaps the most serviceable of the Upper Cretaceous forma-
tions in deciphering structural conditions from well records.
It is true that the transition from the overlying Taylor to the
Austin is gradual, and that there is probably a lack of uniform-
ity on the part of drillers in recognizing the top surface of
the chalk. However, such inconsistencies as arise from this
cause, although of importance in detailed mapping, probably
do not materially affect the accuracy or records when used
in mapping general or regional structures.

The well records here used are those of the Bureau of Eco-
nomic Geology of the University of Texas, and include many
records contributed or made available by several oil companies
and individuals.

In Bexar County, the Austin is found at the surface in a
belt of country extending through the county in a northeast-
southwest direction and passing near, but mostly north of San
Antonio. At its northwest margin this belt of Austin exposures
is marked by a more or less well defined west-facing escarp-
ment. Beyond this escarpment to the northwest, the Austin
is wanting, and the formations at the surface, with the excep-
tion of the Eagleford, are of Lower Cretaceous age. On the'
other hand, to the southeast the Austin passes underneath
later formations and is found, as stated, underlying the oil fields.

Underground Position of Austin Formation in Oil Fields 31

While the Austin passes below the surface to the southeast,
the rate per mile at which it drops to a lower level is by no
means uniform. On the contrary it is found from well records
that while, in places, the formation drops very abruptly to a
lower level, elsewhere it again rises towards the surface, result-
ing in alternately structurally high and low areas.

To the southeast of the Alta Vista and Somerset fields, the
Austin evidently drops to a lower level very rapidly, although
there may of course be as yet undetected interruptions or
reversals in the dip. That the average rate of descent of thp
Austin is rapid, however, is demonstrated by the fact that the
formation, unless greatly altered in character, was not reached
in the Richter well near Pleasanton, about twenty miles south
of the Alta Vista field although drilling Avas continued to a depth
of 4015 feet, or to a level of about 3665 feet below sea level.

In the northwestern part of Atascosa County the Austin for-
mation lies at a depth of 1700 or 1800 feet. The drop to the
Richter well, allowing for difference in elevation, amounts to
not less than 2500 or 2600 feet in fifteen miles. The average
rate of descent in the formation crossing Atascosa County in
a southeasterly direction is therefore not less than an average
of 165 or 175 feet per mile.

In referring to the underground position of the Austin chalk
it is of course understood that this formation is but one of a
series of formations lying in natural order, the one upon the
other, and that where the records are such as to indicate that
one of the formations lies at a relatively high elevation it may
be with confidence concluded that the other formations of the
same series, when not separated by an unconformity, likewise
lie at a relatively high level at that locality. In this way a
certain formation recognizable in well logs may be used in
determining structural conditions, regardless of whether the
formation itself is productive or not, and from structural con-
ditions in turn may be inferred to some extent the probability
of oil production in that particular locality. Accordingly the
Austin, for the reasons given, is here used in depicting the
structural conditions in this region so far as these conditions

32 University of Texas Bulletin

can be shown on a small map and from wells that are in
some parts of the area much fewer in number than could have
been desired.

General Structural Conditions in the San Antonio District

No more than brief reference will be made at this time to
the general structural conditions in the San Antonio district,
these conditions having been somewhat fully described else-
where. The Balcones zone of folding and faulting, as is well
known, passes through this district. The inner margin of this
fault zone (inner in the sense of farthest inland from the Gulf)
is marked in this part of the State by a pronounced south-
east facing escarpment, the trend of the fault zone being north-
east-southwest. Beyond the escarpment to the northwest the
formations, which are those of the Lower Cretaceous, are but
little disturbed by faulting and have a very moderate and
scarcely perceptible dip towards the Gulf. To the southeast
of this escarpment, on the other hand, is a region of profound
disturbance, th$ formations being both faulted and folded.
This disturbed zone is known to be more than twenty miles in
width and it may be much wider. The faults observed are
normal or tension faults, the downthrow being in the direc-
tion of the dip of the fault plane. In most of the faults the
downthrow is to the southeast. This, however, is not invariable
as faults are seen at the surface and recognized in well drill-
ing in which the downthrow is in the opposite direction or to
the northwest. In that case the dip of the fault plane, where
observed, is likewise to the northwest. The faults with down-
throw to the southeast exceed in number, as already stated,
those with downthrow to the northwest; they likewise in gen-
eral exceed in intensity or in amount of throw. Moreover the
regional dip is to the southeast and while there are reversals
of dip, these are seldom continued for any great distance. The
ultimate result of faulting and folding in this zone is to carry
the formations very rapidly to a lower level. When averaged
across the county from the Balcones Escarpment to the eastern
part of Bexar County the rate of drop in the formations will

Underground Position of Austin Formation in Oil Fields 33

be found to fall between 100 and 150 feet per mile, probably
a close approximation to 125 feet per mile. But that such an
average rate of descent can be applied only in the most gen-
eral way, becomes apparent from an inspection of the map and
records which follow.

Contour Map on the Austin Formation

On the accompanying map there is assembled the information
now available on the underground position of the Austin for-
mation in the San Antonio oil fields. The belt of surface
outcropping of the Austin is indicated on this map by the
shaded area. To the east of its outcropping area the position
of the Austin is indicated so far as practicable from records
now at hand, by contouring, the contours being in depth below
sea level as indicated. Likewise the location of the wells used
in contouring is indicated and the depth with respect to sea
level, at which the Austin was found in that particular well,,
is entered on the map.

In this connection it should be stated1 that the surface eleva-
tion of the various wells has been taken largely from the topo-
graphic map, although for a number of the wells not on the topo-
graphic maps the elevation has been determined approximately
by barometer reading's. There is necessarily a small possible
error in elevation of wells, and this should be taken into con-
sideration in using the map. The possible error from this
source, however, is probably less than the average error inci-
dent to recording and interpreting well logs, and is probably
negligible or nearly so in regional mapping.

In 1920 a bulletin on the geology of Bexar County was issued
by the Bureau of Economic Geology, in which structural con*
ditions were indicated by contouring on the Del Rio, a Lower
Cretaceous formation.1 A comparison of the map issued at
that time, with the present map, shows that the major struc-
tural features recognized from the Del .Rio formation, are like-

*The Geology and Mineral Resources of Bexar County, by E. H,
Sellards, University of Texas, Bureau of Economic Geology and Tech-
nology, Bulletin 1932, March, 1920.

34 University of Texas Bulletin

wise shown by contouring on the Austin formation. However,
by the aid of wells drilled during the past two years, the map-
ping has now been extended into Atascosa and Medina coun-
ties. Accordingly the map now issued includes the greater
part, but not all, of Bexar County, and a small part of
Atascosa and Medina counties. In the southeastern part of
Bexar County but little drilling has been done, and in this part
of the county no progress in contouring the underground struc-
ture has been made. For this reason this part of the county
is not included in the present map.

In the map previously issued based on the Del Rio forma-
tion, faulting, so far as recognized from underground records,
was indicated. The present map has been simplified to the
extent of not attempting to indicate such apparent lines of
faulting. It may be stated, however, that such new records
as have been added since the first map was published in so
far as they relate to faulting support the interpretation pre-
viously given.

Structural Conditions as Indicated by Contouring on the
Austin Formation

The outcropping belt of the Austin in Bexar and eastern
Medina counties shows notable irregularities of outline not
accounted for by erosion. Thus in the western part of Bexar
County north of the Portranca public road there is a broad belt
of the Austin which extends in a southwesterly direction into
Medina County. This belt of Austin forms a ridge of much
greater elevation than the plains at either side. The level and
much lower land at the north and at the south is, for the
most part, covered by terrace gravels, but such exposures as
are seen indicate the Taylor formation. When followed to
the southwest, the Austin formation is found to pass under
later formations. Again immediately north of San Antonio
there is found a similar, although much narrower belt of the
Austin formation, extending into the northwestern part of the
city, and forming the surface exposures seen in Brackenridge
and San Pedro parks. Surface exposures of the Austin, in

Underground Position of Austin Formation in Oil Fields 35

UNDERGROUND
OF A i/JTV/v FORMATION
AND PARTS OF MED i HA
ATASC 03 A COUNTIES

Fig. 1. — Map showing approximately the underground position of the Austin
formation in Bexar and in the adjacent parts of Medina and Atascosa Counties.
Shading indicates area where the Austin is at or near the surface, Contours
on the Austin chalk. Contour interval 500 feet. Sea level datum.

36 University of Texas Bulletin

this locality, are found at an elevation of 800 feet or more above
sea, while both to the north and to the south the top of the
Austin is encountered at a much lower level. It is thus ap-
parent that these two belts of Austin exposures are due to
structural conditions. In the case of the Austin exposures in
San Antonio, faults are observed which limit the exposures
at the south, these faults giving rise to the San Pedro, San
Antonio and Salado Springs. At the north side, the Austin
is limited by faults with downthrow to the north or by abrupt
northwest dips in the strata. In the case of the broad1 belt in
the western part of the county, the structural conditions are
produced either by step-faulting or by folding. In each in-
stance the structural feature is a southwest plunging anticline
or fault block.

While these structural features are observable at the surface
in the central part of the county, they are more or less ob-
scured south of the Austin belt by the non-resistant character
of the formations together with the mantling surface materials.
From examination of the well records, however, it becomes
apparent that this type of structure, southwest plunging anti-
clines or fault blocks, is characteristic of the area as far south
at least as the south line of Bexar County. Thus the fault
block seen from surface exposures in the city of San Antonio
may be followed by well records to the oil and gas wells west
of Leon Creek, and possibly also as far as the Medina River.
The Gas Ridge field, which has produced chiefly gas, and in addi-
tion a small amount of oil, is obviously accounted for by this
structural feature.

Another very pronounced structurally high area is that found
at the Alta Vista oil field. At this locality the Austin forma-
tion lies about 300 feet below sea or within about 900 or 965 feet
of the present surface (900 log; 965 samples). Immediately
north of the Alta Vista field the Austin lies at a much lower
level, the difference being so great as to suggest the probability
of faulting with downthrow to the north. The wells of the
Alta Vista and Mission oil fields are located within this struc-
turally high area.

Underground Position of Austin Formation in Oil Fields 37
Relation of Producing Wells to Structure.

The principal groups of producing wells in this region are
indicated on the map. These include the Somerset field, South
Medina and Yturri wells, Alta Vista and Mission pools, and
the Gas Ridge wells. It will be seen that these producing wells
are associated with the structural features of this area. It
is probable that production is controlled in some fields by fault-
ing and in others by folding. In either case production is
likely to come chiefly from the southeast slope of the structurally
high feature. That is, the favorable location for a well is
either on or somewhat east of the axis of the "structure." This
is probably due to the fact that the structural features of this
area are unsymmetrical, the northwest slope being short and1
hence affording but little collecting area for oil. The south-
east slope, on the other hand, in which the strata are returning
to their normal southeast dip, is likely to be long and thus to
afford a considerable collecting ground for oil. With regard
to the kind of faults that favor accumulation, it is to be re-
membered that there 'are many faults of varying intensity mak-
ing up what is known as the Balcones fault zone. Most of
these faults have the downthrow to the southeast, that is in
the direction of the regional dip. Such faults, with downthrow
to the southeast, do not provide favorable conditions for the
accumulation of oil, for the reason that they merely intensify
the rate of dip or descent of the formations to the southeast.
Some of the faults of this zone, however, have the downthrow
to the northwest. In all of these faults, the fault plane dips
towards the downthrow side. In the case of a fault with the
downthrow to the northwest, it follows therefore, that the
"d'rag" which is incidental to faulting amounts to or brings
about a short abrupt dip of the formations in the direction
of the downthrow, or in this instance to the northwest. These
conditions, without doubt, explain the fact that it is the faults
with downthrow to the northwest that bring about conditions
favorable for production, the drag to the fault plane serving as
reverse dip, aided possibly by deposition in the fault plane.

38

I'ni versify of Te.ras Build in

Producing Formations N

With regard to producing formations, more or less produc-
tion, or oil showings, have been obtained from all of the Upper
Cretaceous formations in this area and possibly to some extent
from the Midway, which overlies the Cretaceous. In the Somer-
set field the principal production is from about 500 feet above
the top of the Austin chalk and probably near the contact of
the Taylor and Navarro formations. The Lower Cretaceous now
known to produce oil in Limestone and Caldwell counties, is
present, underlying the Upper Cretaceous.

Well Records

The wells used in recording the underground position of the
Austin formation are listed in the following table. The "map
entry," given in the table, appears also on the map and is in-
tended to assist in locating the well. It records also the eleva-
tion of the top surface of the Austin with respect to sea level
as nearly as has been determined for that particular locality.
Thus the entry 412 records the top of the Austin as 412 feet
above sea level. Entries preceded by the minus sign, as — 1700,
record depth of the Austin below sea level. In addition to
the logs used in mapping a few have been added in Bexar,
Medina, and Atascosa counties, which are beyond the area cov-
ered by the map.

BEXAR COUNTY

Name of Well.

Location.

Eleva-
tion.

Total
Depth.

Top of
Austin.

Map

entry.

\llen , D J

Kelly Field9

(80

1 054

600

80

Applewhite --
Arrowhead Oil Co...

1(5 mi. S

2% mi. W., 1 mi. X.
Somerset

500
650+

1 ,052
1,700

1,896
i,!TO

—1,396
— 920

Basse, E. E

5 mi. N. San Antonio

7<K)T

590

25+

735

Benke, Mrs K

92 mi N W

1 030T

1 000

?00

730

Blue Win? Club
Brendle, H

12 mi. S

527 Bandera St , S A.

490T
720

2,444

1,746
180

—1 ,256
540

Breckenridge Well

Near Salado Creek

630

1,018

70+

.360

Brown, Marathon Oil
Co

2 mi due E Somerset

625+

1 319

894

Cassin

9 mi. S. S. A

550

1,468-

973?

— 493

Clamp, C. C

Collins Gardens

6 mi. west
S. W Pt S A

700
650

1,452

C62
5'75

38
125

Carney, Glen

7% mi. E. of San Antonio

650

1 226

o30+

l-'O

Elder and Wolf

8% mi. S. S. A. (Alt a
Vista)

600

1.'786

9'iO+

—300-

Underground Position of Austin Formation in Oil Fields 39

BEXAB COUNTY— Continued

Nairn' of Woll.

Location.

Eleva-
tion.

Total
! Depth.

Top of

Austin.

Map

entry.

Kn'derick Well - --

71/. mi. S. W. San Antonic

V 6.»

1,200

740

—So

901' Morales St S \

250-f

:425

(iovonmient Well,
\v;>ition Post

6 mi \ E

7.351

«, 374

55H-

680

(Government Well ---

Hackberry St., near Ave
C

(•'SO

729

258

431

Herf IT

4 5 mi W

C'89

i ->e<>

621

62

If;ll and Robv

7.5 mi S

625

1 890

1 200

575

Hofheintz R H

N. of Kelly Field

680

1,453

600

80

Iloltz

9 mi. S. W.

610

1 665

1,900-H

— 575

Hot Well*

4 5 mi S

575

1 878

990

115

Kearney Oil and Pipe
Line Co

12 mi S of S A

610

2 355

957

347

Kreutch O

5.5 mi F S A

678

1 000

420+

255

Kurz

1 mi S E of Somerset

638

1 650

1 450~

SI 2

Legler, W. F.

5 mi. W.

6fl0

1,555

670

95

Linn 9

12 mi. S

550

1 443

1 0°!4

544

Lone Star Brewing
Co

120 Jones Ave.

660

805

248

4l9

La nun 1, Ulf-Varnes
Exploration Co

16 mi. S.

! 500

2 693

9^900-1-

— 1 700

Masterson 1, Meech-
am Oil Co

18 mi. W.

750

2 245

255

495

.Mclntosh, Mrs

7 mi. E. of S. A.

700

668

30+

670

Mathey 1, Bexar Pe-
troleum Co

1 mi. W. Losoya

515

2 332

1 892

1 377

Medina Oil Co

12 mi. S.

530

1 833

1 01?

48°

M. K T Ry

Landa

784

643

60+

724

IVrrinot Well,
Schlather Ind.
Porch Well

2 mi. S. W. Martinex
Iiy2 mi. S.

680T
530T

1,375
1,505

1,239
Not

—559

Ridder \ J

13 mi S W

6°8

2 911

reached

900+

—975+
272

S. A. & A. P. Ry._-
San Antonio City
Water

Pro-baa and Simpson Sts.
Market St.

630

650

1,103

880

500

2?0

130
430

"San Antonio City
Water

Conception Mission _-

605

1,440

780

175

San 'Antonio Port

5 mi N .

740

C67

60

680

Schmidt, Marathon
Oil Co

1% mi. due E. Somerset

635+

1 579

944

Shatuck Well

19th St. WT.

678

6(i7

335

343

Smith, Sarach
Southern Ice Co

2 mi. E. S. E. of Somerset
Frio and Durango Sts

650±
655

1,668
822

Not
reached
280

—1,018+
395

Southwest Land Cor-
poration

4 mi. W.

708

1,000

390

318

Somerset Well ...

Somerset, cored by Kerr at

'St Louis College

1600. Austin 1,560-1,930.
W. 5.1

650

760

2,320

7Q9

1,560
215

—910
545

"Steves Mrs J

Steves Garden

645

1 185

604

41

'Steves Mrs J

509 King Williams St

645

758

250

395

Steves Ed

8.5 mi. S. of S. A.

660

1 840

j 300-+-

(340+

'Sullivan, D.

3y2 mi. S. E-. of S. A

620

1,100

505+

115

Taft, L S

7 mi. E. of S. A.

666

1 240

880

215

Terrell Hot WelL-
Terrell, J. H

5.2 mi. S. of S. A
S. W. city limits, S. A.

630
675

1,956
1,140

1,000
550

—370
12'>

Texas Steam Laun-
dry.

205 Losoya St

€65

748

290

375

Tommins, R.

South city limits, S. A.-

630

1,500

900 i

—270

Union Meat Co

Laredo and Ralph Sts.,
S. A.

640

1 400

340

qnn

Voght, Win.
Walsh, Meechum Oil
Co

Waring Well
Vturri 1, W. H.
Reynolds et al

14, mi. S. W. of S. A.__.

12 mi. S. of S. A.—.
7.5 mi. N. W. of S. A._.

Wz mi. S. San Antonio—

605

550

920 •

510±

1,850

1,736
2,853

3,460

985±

1,403
13

1,476?

—380

—353
907

966?

40

University of Texas Bulletin

MEDINA COUNTY

Name of Well.

Location.

Eleva- Total '
tion. Depth, j

Top of i
Austin, i

i

Map

entry.

Blackaller 1, Mid-
Ffio Oil Co

5 mi. E. and 3 mi. N. of
the S. W. corner of
county

SOOT 3 115

1 %0

-1 160?

W. Garnand, Somer-
set, Western Oil Co.

Thomas Surv. 516

745 1 648

1 550

805

Gray Well

Abt 1 mi S E I ytle

8 mi., 113% Tli. Thomas

Haas, Geo.

414 mi S WT of Dun!ay

1 000 1 000

97 5> j

125

Kimble, Osman Oil
Co

Near Devine, 2 mi. S. W.

McClure, T. S., 1—

S. Reiden, John No. 28
3 mi. S. W. Dunlay Sta.
on S. P. Ry. See T. S.
McClure, 142 Goliad St.

670 2,540
1,233

2,287
740

—1.617

ATASCOSA C01

JNTY

Name of Well.

Location.

Eleva- Total
tion. Depth.

Top of

Austin.

Map

entry.

Caruthers 11, Gray-
burg Oil Co

About 2 mi. S. W. Somer-

set

••> 375

1 775

Childress No. 1, Lem-
ing Oil & Gas Co.
Now owned by Hol-
lingsworth, Pleas-
an on

1 mi. S. of Leming

450A . 2,600

Not

Foster, Grayburg Oil
Co.

Somerset Oil Field && mi.

reached

—2,150+

W. S. W. Somerset Sur-
vey 523

745 \

1 US;

Fowler, Gulf Produc-
tion Co. Powler
Lease No. 2

Somerset Oil Field 2. mi.

S. W. Somerset

1,8*9

1,825

— 1,175,

Hartung Loase 1. W.
1. Grayburg Oil Co.

Survey 140, 3 mi. ± S. W.
Somerset

1 979

1 968

1 °13~

Hartune: 17, Gray-
burg Oil Co.

4% mi. S. W. Somerset

Surv. 385, J. J. Knott..

2,729

2,290

—1,640-

McCain Lease 1. W.
2. Grayburg Oil
Co

' Survey 1,970, S. W. of

Muennick Well 2.
Grayburg Oil Co

Somerset

Atascosa County

1,975
1 903

1,973
1 Q03

' —1,323
1 953

Richter 1, Galvan Oil
Co

'l1/^ mi. N. E., Pleasanton

E. H.,, Timmons Surv.,
N. W. part

350 \ 4 015

\}Qt

' reached

—3,665+

AN INITIAL FINE OF 25 CENTS

OVERDUE.

LD 21-100m-7,'3!

Binder
Gaylord Bros- !««•

St,ckton, Calif.
T.M. Rea-U. S.Pat- Off

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