NEW MEXICO BUREAU OF GEOLOGY AND MINERAL RESOURCES A DIVISION OF NEW MEXICO INSTITUTE OF MINING AND TECHNOLOGY
105°30'0"W
454000
455000
105°27'30"W
456000
457000
458000
459000
105°25'0"W
460000
461000
462000
463000
105°22'30"W
464000
Mayhill Quadrangle Unit Descriptions:
465000
NMBGMR Open-file Geologic Map 155
Last Modified 10 July 2007
Permian Rocks
33°0'0"N
33°0'0"N
3651000
3651 000
Psr
9
Psb
Psb
7
5
Qal Py
Py
3
5
10
Qal
Qal
13
Psb
5
Psb
9
Psb
3650000
3650 000
Psr: Rio Bonito Member of the Permian San Andres Formation
3649 000
The Rio Bonito member of the San Andres formation is a gray to brownish gray locally
fossiliferous micritic limestone and dolomite, similar to the younger Bonny Canyon member
(Psb). A generally more thickly bedded and massive unit than the Psb, the Rio Bonito is
characterized by 5-50 cm-thick beds. This unit occurs on slopes and lower ridgetops in the
eastern part of the map area, as well as in canyon bottoms on the western part of the quadrangle
where no Yeso is exposed. Near the base of the Rio Bonito member occur lenses of fine-medium
grained rusty quartz arenite sandstone, believed to be equivalent to the Glorieta sandstone (Kelly,
1978). The Glorieta sandstone is not entirely continuous, but it can generally be found along
strike within 500 feet of where it pinches out. As this is the only documented and recognized
non-carbonate lithology within the San Andres formation, it was generally utilized to map the
contact between San Andres and carbonate-bearing Yeso formation. The Glorieta sandstone
commonly occurs 60-120 feet above the base of the San Andres formation (Pray, 1961). As little
or no outcrop occurs in much of the map area, the location of this contact was generally estimated
relative to the highest float blocks of Glorieta sandstone. The Rio Bonito member thickens to the
south, and in the Mayhill area it is approximately 400 feet thick (Kelley, 1978).
Qal
4
14
5
11
Psb
6
4
3
11
6
Psb
4
12
Py
7
Psb
Psb
Psb
7
3649000
3
5
8
4
4
Psb
4
6
8
5
4
Psb
5
Psb
Psb
5
3648000
A heterogeneous unit of mudstone, limestone, dolomite, and evaporates, the Yeso occurs mainly
in canyon bottoms and lower slopes in the eastern part of the map area. The Yeso is best
recognized by pinkish-red to yellow claystones and siltstones. Evaporite lithologies, mainly
gypsum in surface exposures, are less common in the upper part of the Yeso exposed in the
Mayhill quadrangle. Carbonate occurs throughout the Yeso, yet is more common near the top of
the Yeso, generally above a thick package of mudstones. Yeso carbonate is generally more tan in
color and more thinly bedded than the gray carbonates of the Rio Bonito member of the San
Andres formation. Measured sections of the Yeso range from ~ 1200 to 1500 feet in thickness
(Pray, 1961)
6
10
4
Py: Permian Yeso Formation
11
Psb
3648 000
5
6
Psb: Bonney Canyon member of the Permian San Andres Formation
4
Qal 4
12
Py
4
15
85
5
7
5
6
9
Psb
77
Py
12
Psb
5
10
Psr
3647000
Psb
Psb
5
Psb
5
4
Psb
5
5
3647 000
Psb
Psb
Psb
32°57'30"N
32°57'30"N
Psb
6
7
Cenozoic Surficial Deposits
Py
Qal: Quaternary Alluvium
Psb
3646000
3646 000
5
Holocene and older stream and minor terrace deposits. This unit fills valley floors and is
characterized as a sandy gravel composed of mainly carbonate clasts and minor quartz sandstone
(Glorieta).
Qal
QTa: Older Alluvium
6
8
Psb
4
Psb
4
Py
7
5
5
Py
5
6
5
4
Psr
10
6
5
3645000
4
3
Psb
Psb
3645 000
Psb
Psb
3
Psb
6
Psb
Py
Psb
Qal
Minor debris flow deposit in Browning canyon. A moderately to well consolidated
matrix supported sandy gravel along the walls of Browning canyon. This unit is poorly exposed
and recently incised. Clasts are subrounded carbonates
Psr
86
4
4
4
Psb
4
3644 000
Psb
3
3
Qal
20
3644000
8
8
Psb
8
4
Qal
Psb
Qal
Psb
Qal
6
6
5
Qal
9
Py
QTdf
Psb
11
3643000
3643 000
8
Psb
5
Py
Qal
Psb
3
7
7
5
4
3
8
QTa
QTa
10
Psr
Psb
3642000
4
7
Qal
Psb
QTa
10
Py
4
15
Psb
14
QTa
Psr
24
90
Psb
8
Py
Psb
QTa
Psb
4
Psr
3641000
90
11
32°55'0"N
Psb
10
6
3642 000
7
4
32°55'0"N
Psb
Psb
Qal
Qal 3
Psr
4
Qal
3
9
Psr
A
Qal
3
5
QTa
Qal
Psb
3641 000
5
Qal
Psb
A'
Psb
3
Psb
3
Psb
QTa
6
3
6
3640000
3640 000
Psb
Psr
Psr
5
6
Psb
3
Psb
Qal
5
6
6
17
5
Psr
4
10
3
Psb
4
3639000
3639 000
Psb
6
3
27
Psb
8
5
5
5
QTa
Psr
6
Py
Psb
17
Psb
Psr
3638 000
6
3638000
Psb
Psb
Psb
Qal
Psb
Qal
Psb
29
Psb
9
Qal
Psb
Psr
4
32°52'30"N
Psb
3
32°52'30"N
3637000
3637 000
454000
105°30'0"W
455000
456000
457000
458000
105°27'30"W
459000
460000
461000
105°25'0"W
Base map from U.S. Geological Survey 1963, from photographs taken 1963, field checked in 1963.
1927 North American datum, UTM projection -- zone 13N
1000-meter Universal Transverse Mercator grid, zone 13, shown in red
1:24,000
ELKSILVER
TURKEY
PEAK
1
CLEMENTS
RANCH
NEW MEXICO
HARVEY
RANCH
SACRAMENTO
MAYHILL
Mayhill
WOODSON
CANYON
0.5
1000
0
0
1000
2000
3000
1 MILE
4000
5000
6000
7000 FEET
ELK
1
ROBERTSON
CANYON
Magnetic Declination
June, 2006
9º 3' East
At Map Center
0.5
0
462000
463000
464000
465000
105°22'30"W
Geologic map of the Mayhill
quadrangle, Otero County, New Mexico
June 2007
1 KILOMETER
CONTOUR INTERVAL 40 FEET
NATIONAL GEODETIC VERTICAL DATUM OF 1929
by
Benjamin Hallett
New Mexico Bureau of Geology and Mineral Resources, 801 Leroy Pl., Socorro, NM, 87801
QUADRANGLE LOCATION
This draft geologic map is preliminary and will undergo revision. It was produced
from either scans of hand-drafted originals or from digitally drafted original maps
and figures using a wide variety of software, and is currently in cartographic production.
It is being distributed in this draft form as part of the bureau's Open-file map series
(OFGM), due to high demand for current geologic map data in these areas where
STATEMAP quadrangles are located, and it is the bureau's policy to disseminate
geologic data to the public as soon as possible.
After this map has undergone scientific peer review, editing, and final cartographic
production adhering to bureau map standards, it will be released in our Geologic Map
(GM) series. This final version will receive a new GM number and will supercede
this preliminary open-file geologic map.
DRAFT
New Mexico Bureau of Geology and Mineral Resources
Open-file Geologic Map 155
Mapping of this quadrangle was funded by a matching-funds grant from the STATEMAP program
of the National Cooperative Geologic Mapping Act, administered by the U. S. Geological Survey,
and by the New Mexico Bureau of Geology and Mineral Resources, (Dr. Peter A. Scholle,
Director and State Geologist, Dr. J. Michael Timmons, Geologic Mapping Program Manager).
Additional funding made possable by the Otero County Soil and Water Conservation District.
New Mexico Bureau of Geology and Mineral Resources
New Mexico Tech
801 Leroy Place
Socorro, New Mexico
87801-4796
[505] 835-5490
http://geoinfo.nmt.edu
This and other STATEMAP quadrangles are (or soon will be) available
for free download in both PDF and ArcGIS formats at:
http://geoinfo.nmt.edu/publications/maps/geologic/ofgm/home.html
Terrace and alluvial fan deposits. This unit occurs mainly at the mouths of smaller side
canyons where they run into James Canyon and the Rio Penasco valley. Composed of fine to
coarse subrounded carbonate pebbles, most with calcic rinds, in a reddish silty sand matrix.
Layers often alternate between more fine and more coarse, and commonly show clast imbrication.
QTa is moderately consolidated and generally at a higher level than Qal.
QTdf: Debris Flow Deposit
3
5
Qal
A gray to brownish gray locally fossiliferous micritic limestone and dolomite, the
Bonney Canyon member of the San Andres formation is characterized by generally 2-20 cm-thick
bedding. This is in contrast to the more massive Rio Bonito member. Fauna include crinoids and
ammonites. As no distinct stratigraphically recognizable marker bed indicates the Bonney
Canyon – Rio Bonito contact, mapping of this contact was primarily done by aerial photo
analysis. Kelly (1978) suggests that the thinner bedding of the Bonney Canyon results in a
greater permeability and thus greater tree cover in areas dominated by pinyon and juniper forest.
As a result, in the map area this member shows a distinct bulls-eye pattern of tree cover that
follows the outcrop of local beds. In general, the transition from the Rio Bonito member to the
Bonney Canyon member was mapped as a light band just below the start of this bulls-eye pattern
of denser tree cover. The Bonny Canyon member is nowhere completely exposed on the Mayhill
Quadrangle, yet its thickness in the area is estimated at ~300 feet (Kelley, 1978).
COMMENTS TO MAP USERS
A geologic map displays information on the distribution, nature, orientation, and age relationships
of rock and deposits and the occurrence of structural features. Geologic and fault contacts are
irregular surfaces that form boundaries between different types or ages of units. Data depicted
on this geologic quadrangle map may be based on any of the following: reconnaissance field
geologic mapping, compilation of published and unpublished work, and photogeologic interpretation.
Locations of contacts are not surveyed, but are plotted by interpretation of the position of a given
contact onto a topographic base map; therefore, the accuracy of contact locations depends on the
scale of mapping and the interpretation of the geologist(s). Any enlargement of this map could cause
misunderstanding in the detail of mapping and may result in erroneous interpretations. Site-specific
conditions should be verified by detailed surface mapping or subsurface exploration. Topographic
and cultural changes associated with recent development may not be shown.
Cross sections are constructed based upon the interpretations of the author made from geologic
mapping, and available geophysical, and subsurface (drillhole) data. Cross-sections should be used as
an aid to understanding the general geologic framework of the map area, and not be the sole source
of information for use in locating or designing wells, buildings, roads, or other man-made structures.
The map has not been reviewed according to New Mexico Bureau of Geology and Mineral Resources
standards. The contents of the report and map should not be considered final and complete until
reviewed and published by the New Mexico Bureau of Geology and Mineral Resources. The views and
conclusions contained in this document are those of the authors and should not be interpreted as
necessarily representing the official policies, either expressed or implied, of the State of New Mexico, or
the U.S. Government.