NEW MEXICO BUREAU OF GEOLOGY AND MINERAL RESOURCES
NMBGMR Open-file Map Series OFGM 35
A DIVISION OF NEW MEXICO INSTITUTE OF MINING AND TECHNOLOGY
Last Modified May 2003
IA
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Pennsylvanian
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106º05'
Base mapped, edited, and published by the Geological Survey. Control by USGS and USC&GS
Topography from aerial photographs by multiplex methods
Aerial photographs taken 1952. Field check 1954
Polyconic projection. 1927 North American datum
10,000-foot grid based on New Mexico coordinate system, cental zone
Digital cartography by K. Glesener, M. M. Mansell, and D. J. McCraw
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CHILILI 16 MI.
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3
R. 7 N.
0.5
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7000 FEET
CONTOUR INTERVAL 20 FEET
TH
T IC N O R
MAG N E
TRUE NORTH
10°
QUADRANGLE LOCATION
O
RI
AR
TY
SO
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New Mexico Bureau of Geology and Mineral Resources
New Mexico Tech
801 Leroy Place
Socorro, New Mexico
87801-4796
1 KILOMETER
NATIONAL GEODETIC VERTICAL DATUM OF 1929
NEW MEXICO
35º00'
106º07'30" (M
397000m.E.
R. 8 N.
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. Paul W. Bauer, Geologic Mapping Program Manager).
1 MILE
4000
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1:24,000
1
3874000m.N.
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10'
(CHILILI)
Sol se Mete Member — Approximately 75 m (~250 ft) of the upper part of
the member is exposed in the map area. The upper 5 to 10 m (~15 to 30 ft)
of the unit is dominated by thick beds of ledge-forming limestone.
Underlying deposits consist of yellow, gray, and red shale with discontinuous
siltstone and sandstone interbeds, and limestone beds that range from less
than one to a few meters in thickness. Limestone beds are typically
mudstones and wackestones, although brachiopods, crinoid stems, and other
bioclasts are abundant in some intervals. Two limestone intervals containing
abundant Triticites, one near the top of the Sol se Mete and another
approximately 30 m (~100 ft) below the top of the unit can be traced laterally
in the northern part of the map area. Total thickness of the Sol se Mete is
assumed to be 90 m (~300 ft) on the cross sections.
Los Moyos Limestone (Middle Pennsylvanian) (cross sections only) — On
adjoining quadrangles to the west and southwest, the Los Moyos Formation is
characterized by several meter-thick intervals of thin- to thick-bedded limestone
and thin shale and calcareous shale interbeds, separated by one to several
meter-thick intervals containing relatively abundant, fine-grained siliciclastic
sediment. The formation also contains relatively minor sandstone and pebbly
sandstone interbeds. Limestones commonly contain abundant chert. Overall the
Los Moyos Formation contains a higher proportion of limestone relative to
siliciclastic sediments than in the overlying Wild Cow Formation. Assumed to be
180 m (~600 ft) thick on the cross sections.
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Pine Shadow Member — Approximately 40 m (~130 ft) of the lower part of
the member is exposed in the map area, where it consists of 2 to 3 siliciclastic
intervals, several meters thick, and intervening intervals, up to a few meters
in thickness, dominated by ledge-forming limestone beds. Siliciclastic
intervals are generally poorly exposed and contain thin interbeds of tabularand nodular-weathering limestone and calcareous shale. A one- to
several-meter-thick sandstone to silty sandstone commonly crops out
approximately 12 m (~40 ft) above the base of the member in the map area.
Exposed blocks of sandstone from this interval are generally red to yellow,
are composed of fine- to coarse-grained sand and pebbly sand, and are
quartzose to arkosic. Ledge-forming limestone intervals typically consist of
mudstones and wackestones, although coarse skeletal fragments are abundant
in some beds. Fusulinids are abundant in the lower few meters of the map
unit. Total thickness of the Pine Shadow is approximately 60 to 90 m (200 to
300 ft) thick on adjoining quadrangles to the west and southwest.
Qcr
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T. 9 N.
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T. 10 N.
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T. 9 N.
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T. 10 N.
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Qp2
MORIARTY 4.8 MI.
SANTA ROSA 84 MI.
Qcr
Wild Cow Formation (Upper Pennsylvanian) — Approximately 115 m (~380 ft)
of the lower part of the Wild Cow Formation is exposed across the map area.
Outcrops are largely restricted to limestone ledges and resistant sandstone beds;
exposures of fine-grained siliciclastic intervals are generally limited to roadcuts and
the walls of arroyos.
Qc
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Qa
Qcr
Alluvium, colluvium, and residuum on valley backslopes and interfluvial
summits
in
bedrock
uplands
(Middle
Pleistocene
(?)
to
Holocene)—Predominantly silt, clay, and sand. Derived from weathering of the
Madera Group (residuum on relatively flat-laying areas), and from downslope
transport of weathering products. Mapped where accumulations cover extensive
areas and are sufficiently thick to support large areas of grass cover. Also includes
areas of unmapped bedrock exposure. Unit ranges from less than one to several
meters in thickness.
Qp3
Qp
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D U
Upland-valley alluvium and colluvium (Middle Pleistocene (?) to Holocene) —
Predominantly silt, sand, and gravel grading into relatively coarse-grained
colluvium along valley backslopes. Along high-order drainages unit consists of
eroded older deposits and younger inset fills. Includes unmapped bedrock
exposures along valley backslopes. Thickness ranges from a few meters or less in
upland valleys and over bedrock highs, to an estimated 10 m or more along trunk
drainages.
Qc
Qa
Qp
7
Qa
Qc
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Piedmont alluvium underlying highest interfluvial summits in map area
(Middle to late Pleistocene (?)) — Predominantly sand and silt, with
varying amounts of gravel and clay. Unit has been extensively incised in
vicinity of major drainages, and is underlain by older basin-fill deposits.
Qp
3
Qa
Qcr
Qc
Qp2
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4
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Qa
Qp
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Qc
Qp3
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Qvac
Qvac
Qc
Qa
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5
Qvac
Piedmont alluvium, inset into unit Qp2 and older basin-fill deposits
(Middle to late Pleistocene (?)) — Predominantly sand and silt, with
varying amounts of gravel and clay. Unit comprises extensive deposits along
major drainages. Estimated thickness is 3 m or more, although some areas
mapped as Qp3 may represent erosional surfaces with minimal accumulation
of overlying fill.
Qa
Qa
(SEDILLO)
Qc
Qp3
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2
Qvac
Qa
Qc
Qp3
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Qp4
Qa
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Qc
Proterozoic
[505] 835-5490
Geology of Edgewood quadrangle,
Torrance and Santa Fe Counties, New Mexico
Sandia Formation (Middle Pennsylvanian) (cross sections only) — On
adjoining quadrangles to the west and southwest, the Sandia Formation consists of
sandstone, shale, and pebbly sandstone, with thin interbeds of limestone and
calcareous shale in some areas. The thickness of the Sandia Formation is variable,
with an average thickness of about 45 m in the Sandia Mountains (Kelley and
Northrop, 1975) and ranging up to about 90 m in the Manzano Mountains (Myers,
1988). Pre-Sandia Formation (Mississippian (?)) sedimentary rocks in the map
area, if present, are included in the Sandia Formation in the accompanying cross
sections, with an assumed, overall thickness of the combined Sandia Formation
plus pre-Sandia strata of 45 m (~150 ft).
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Proterozoic crystalline rocks, undifferentiated (cross sections only).
35º 05'
40
Moriarty
Map area
Estancia
Basin
Drainage
Divide
10
Availability of groundwater from wells in the Madera Group aquifer system is generally thought to
depend on fractures and dissolution channels in limestone units (Titus, 1980), although siliciclastic
intervals may contribute to the yield of some wells. Evidence for subsurface dissolution of limestone in
the area includes sinkholes at the surface and the Edgewood caverns (accessible through the casing of a
dry borehole) north of the town of Edgewood. Because of the interbedded lithologies of the Madera
Group and resulting heterogeneity with respect to groundwater flow, confined or semi-confined aquifer
systems and local, perched aquifers may exist. Compared to areas immediately underlain by bedrock on
the Edgewood quadrangle, the shallow aquifer system to the east of the map area, along the axis of the
Estancia basin, consists of unconsolidated sediments of the Estancia basin-fill. Wells in the basin-fill
aquifer system are capable of yielding 100s of gallons per minute and yield sufficient groundwater for
extensive agricultural activity toward the axis of the basin. The Edgewood quadrangle is located along
the transition from upland areas dependent on the Madera Group aquifer system, to areas that utilize the
basin-fill aquifer system of the Estancia basin to the east.
Quaternary Map Units
Unconsolidated surface deposits in the map area consist of upland-valley alluvium and colluvium, and
piedmont alluvium and colluvium derived from weathering of shale, limestone, and sandstone of the
Pennsylvanian Madera Group. Sediment transport is toward the east and the western piedmont of the
topographically closed Estancia basin. Map units consist of valley-floor alluvium associated with
modern drainages (Qa), upland valley alluvium and colluvium (Qvac), alluvium, colluvium, and
residuum on valley backslopes and bedrock uplands (Qcr), and piedmont alluvium and colluvium (Qp
and Qc). Downcutting and overall basinward shifts in deposition on the Estancia basin piedmont have
resulted in a stepped sequence of surface deposits that are generalized on the map to include an older
unit that caps the highest interfluvial summits (Qp2), and younger inset fills (Qp3, Qp4, and Qa).
Unconsolidated deposits in upland valleys are generally on the order of 10 m. thick or less, but may be
20 m. thick or more in places, especially in the large N–S-trending valley on the western edge of the
map. Unconsolidated deposits in the Estancia basin to the east of the map area reach a maximum
thickness of ~120 m. (New Mexico State Engineer, 1967). Maximum thickness of unconsolidated
deposits along the Estancia basin piedmont within the map area is on the order of 30 to 40 m, based on
well-driller's logs for the area. These piedmont-slope deposits include the surface deposits shown on the
map, and underlying, older deposits that are referred to here as the Estancia basin fill.
Xu
(1946) in the vicinity of the Lucero uplift. Recent recommendations to simplify the
stratigraphic nomenclature of Pennsylvanian rocks in New Mexico (Kues, 2001) suggest
that the formation names Los Moyos and Wild Cow may eventually be abandoned in favor
of the names Gray Mesa and Atrasado, which have precedence.
Absolute ages for Quaternary map units on the Edgewood quadrangle are not available. Relative ages
for piedmont surface deposits are indicated by inset relationships. Older surface deposits on the
piedmont contain well-developed, pedogenic accumulations of carbonate (stage II to stage III carbonate
development), suggesting late and perhaps middle Pleistocene ages for units Qp2 and Qp3. Little is
known regarding the age of older basin-fill deposits that are covered by the surface deposits shown on
the map. These older deposits may range in age from Pliocene to late Miocene (Smith, 1957). Geologic
events leading to topographic closure of the Estancia basin, and the timing of basin closure, are also
speculative.
Myers (1988) concluded that most of the Los Moyos limestone lies within the fusulinid
zone of Beedeina, indicating that the unit is correlative to Desmoinesian strata of the
mid-continent. The overlying Wild Cow Formation lies within the zone of Triticites, and
corresponds for the most part to Missourian and Virgilian strata of the mid-continent. The
Wild Cow Formation was subdivided by Myers (1973) into three members. The three
members in ascending order are the Sol se Mete, Pine Shadow, and La Casa. Each of the
three members conceptually consists of a basal sequence containing an abundance of
siliciclastic beds that grade upward into capping intervals dominated by carbonate-shelf
limestones. Subdivision of the Madera Group on the geologic map and cross sections uses
this nomenclature of Myers (1973). Surface exposures in the map area are probably limited
to portions of the Sol se Mete and Pine Shadow Members of the Wild Cow Formation.
Bedrock Map Units
Structure
Surface exposures of bedrock in the map area belong to the Madera Group. The Middle to Upper
Pennsylvanian (Desmoinesian-Virgilian) Madera Group includes marine and marginal-marine carbonate
and siliciclastic sediments consisting of interbedded limestone, shale, sandstone, and minor
conglomeratic sandstone. The thickness of the Madera Group in the vicinity of the Sandia and Manzano
Mountains ranges from about 400 m (Kelley and Northrop, 1975) to perhaps 580 m or more (Read, et
al., 1944, measured section 14), and has traditionally been divided (e.g., Read, et al., 1944; Kelley and
Northrop, 1975) into a lower unit containing a large proportion of limestone (“lower gray limestone”),
and an upper unit containing a large proportion of siliciclastic sediments (“upper arkosic limestone”).
The Madera Group gradationally overlies rocks of the Middle Pennsylvanian (Atokan) Sandia
Formation, which is also marine to marginal-marine in origin and is dominated by siliciclastic
sediments. The Sandia Formation generally overlies Proterozoic crystalline rocks in the area, although
a thin (up to 20 m. thick) sequence of limestone and shale deposited during the Mississippian (?) occurs
between the Sandia Formation and Proterozoic crystalline rocks at several localities in the Sandia and
Manzano Mountains (Kelley and Northrop, 1975). The Madera Group is gradationally overlain by the
Bursum Formation (Virgilian-Wolfcampian), which, in the Manzano Mountains, consists of interbedded
siliciclastic sediments with a few thin limestone interbeds. The Bursum Formation was probably
deposited as the last of the Pennsylvanian seas withdrew from the area, and is overlain by continental
redbeds of the Permian Abo Formation.
The Edgewood quadrangle lies several km to the east of the NE-SW trending
Tijeras-Gutierrez structural zone, which exhibits a variety of structural features including
faults and folds within Phanerozoic sedimentary rocks and surface exposures of Proterozoic
basement. The region was subjected to compression during the latest Mesozoic–Paleogene
Laramide orogeny, followed by Neogene extension that resulted in formation of the Rio
Grande rift to the west (Karlstrom, et al., 1999). To the east of the Tijeras-Gutierrez
structural zone in the vicinity of the Edgewood quadrangle, sedimentary rocks of the Madera
Group occur near the surface and generally dip a few degrees toward the east. This
eastward-dipping structural trend, as noted by Kelley and Northrop (1975), is disrupted by a
N-S trending, down-to-the-west fault zone that cuts across the Edgewood quadrangle. This
structure is expressed geomorphically by the large N-S trending valley on the western edge
of the map and the ridge immediately to the east of this valley. Limited field evidence,
including the geometry of the probable trace of the fault with respect to topography, and a
single fault-plane exposure in the southwestern part of the map area, is consistent with
reverse movement across the fault zone. Three approximately E-W trending faults are
present just to the east of this N-S trending structure, one in the northern part of the map area
and the other two just south of the Bernalillo - Torrance county line. Limited exposures of
barite, fluorite, and calcite mineralization are present in the vicinity of the latter two E-W
fault zones, and in Section 7, T. 9 N., R. 7 E. A zone of apparent hydrothermal alteration is
present in the northwestern part of the map area in Sections 6 and 7, T. 10 N., R. 7 E. that is
visible on aerial photographs as a linear, approximately N 15 W trending feature. Field
evidence for vertical displacement across this feature was not found and it is not mapped as
fault.
Subdivision of the Madera Group in the Manzano Mountains was formalized by Myers (1973), who
elevated the Madera to group status and designated two formations within the Madera – the Los Moyos
limestone and the overlying Wild Cow Formation (Myers also included the Bursum Formation in the
Madera Group). The Los Moyos limestone and Wild Cow Formation generally correspond to the earlier
concept of lower gray limestone and upper arkosic limestone members of the Madera “Formation.” As
noted by Myers (1973), the Los Moyos and Wild Cow Formations are likely equivalent to the Gray
Mesa and Atrasado Members, respectively, of the Madera “Formation” as defined by Kelley and Wood
The overall eastward dip of the Madera Group in the map area is modified by what appear
to be broad, low amplitude, roughly E-W trending folds. These undulations are expressed
by latitudinal changes from NW striking to NE striking beds. Sub-vertical joint sets in
exposed bedrock are common and orientations of joint traces (see rose diagram of joint
orientations) are similar throughout the map area.
Geologic Cross Sections
7,000’
Explanation of Map Symbols
Location of geologic cross section.
5
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15%
10
5
E
W
Rose diagram of joint orientation data,
Edgewood quadrangle. N = 303.
References
Karlstrom, K.E., and others, 1999, Sandia Mountains and Rio Grande rift:
ancestry of structures and history of deformation: New Mexico
Geological Society, Guidebook 50, p. 155-165.
Kelley, V.C., and Northrop, S.A., 1975, Geology of Sandia Mountains and
Vicinity, New Mexico: New Mexico Bureau of Mines and Mineral
Resources, Memoir 29, 135 p.
Kelley, V.C., and Wood, G.H., 1946, Lucero uplift, Valencia, Socorro, and
Bernalillo Counties, New Mexico: U.S. Geological Survey, Oil and Gas
Investigations Preliminary Map 47, scale approx. 1:62,000.
Kues, B.S., 2001, The Pennsylvanian System in New Mexico- overview with
suggestions for revision of stratigraphic nomenclature: New Mexico
Geology, v 23, p. 103-122.
Myers, D.A., 1973, The upper Paleozoic Madera Group in the Manzano
Mountains, New Mexico: U.S. Geological Survey Bulletin 1372-F, 13 p.
Myers, D.A., 1988, Stratigraphic distribution of fusulinid foraminifera from
the Manzano Mountains, New Mexico: U.S. Geological Survey
Professional Paper 1446, 65 p.
New Mexico State Engineer, 1967, Thickness of alluvium, valley fill, and lake
deposits, Estancia underground water basin: Santa Fe, New Mexico
State Engineer Office, Open-file Map, scale 1:126,720.
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Xu
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Titus, F.B., 1980, Ground water in the Sandia and northern Manzano
Mountains, New Mexico: New Mexico Bureau of Mines and Mineral
Resources, Hydrologic Report 5, 66 p.
7,000’
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Qp
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6,000’
Geologic contact. Dashed line indicates approximate
location.
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.
feet ASL
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Normal fault showing dip direction, ball-and-bar on
downthrown side. Solid where exposed, dashed where
approximately known, dotted where concealed. “D”
indicates downthrown side of concealed fault; “U”
indicatesupthrown side. Tick indicates dip of fault
plane.
N
Smith, R.E., 1957, Geology and ground-water resources of Torrance County,
New Mexico: New Mexico Bureau of Mines and Mineral Resources,
Ground-water Report 5, 186 p.
A'8,000
8,000
feet ASL
U
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Read, C.B., and others, 1944, Geologic map and stratigraphic sections of
Permian and Pennsylvanian rocks of parts of San Miguel, Santa Fe,
Sandoval, Bernalillo, Torrance, and Valencia Counties, north-central
New Mexico: U.S. Geological Survey, Oil and Gas Investigations
Preliminary Map 21, scale approx. 1:190,000.
Comments to Map Users
D
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&s
A
65
Qp2
&wp
Map showing location of Edgewood quadrangle, generalized geology, and physiographic features. Surface
drainage to the east is into the topographically closed Estancia basin.
STATEMAP quadrangles are available
for free downloads at:
http://geoinfo.nmt.edu
New Mexico Bureau of Geology and Mineral Resources, Socorro, NM 87801
A'
Qcr
20 km
by
A
Qvac
10 mi
5
0
Bruce D. Allen
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.
Qp3
\
May 2000 (revised May 2003)
APPROXIMATE MEAN
DECLINATION, 2003
Qc
Qp
Edgewood
0
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&ws
Qp2
Qc
Qp4
Qp3
Qp2
Qcr
Qvac
Qc
Qc
Qc
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Qa
Qvac
Qp3
Qa
Qvac
Qvac
05'
Rio Grande
Basin
lope
Qa
05'
Paleozoic-Mesozoic
Sedimentary Rocks
anzano Mtns
Qp4
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Qp
Qp3
\
Piedmont alluvium, inset into unit Qp3 and older basin-fill deposits (Late
Pleistocene to Holocene(?)) — Predominantly sand and silt, with varying
amounts of gravel and clay. Represented in the map area by deposits along
Bachelor Draw. Estimated thickness is about 3 m.
ont S
Piedm
o
Qp3
Qc
Qp
Qp
Qa
Qp3
Qc
Qc
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Qc
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Manzanita - M
Qvac
Qc
Qp
Qp
\
nt
mo
ed
o
Qc
Tertiary
Intrusion
Pi
Qc
&ws
5
ALBUQUERQUE 25 MI.
8.6 MI. TO N. MEX 10
Qc
Qc
Qp
Qa
Qc
106º 20'
Sandia Mtns
Qp2
5
&ws
Middle and upper piedmont-slope alluvium and colluvium (Middle Pleistocene
(?) to Holocene) — Includes alluvial fan and coalescent alluvial fan complex along
western uplands of the Estancia basin, and younger, inset alluvial fills. May also
include contributions of eolian sediment. Predominantly silt and sand, with coarser
grained beds dominated by sand and gravel present in the vicinity of uplands and
along high-order drainages. Undivided unit (Qp) is mapped along the upper
piedmont slope where it forms a relatively thin mantle (generally less than 10 m
thick) over bedrock, and is depicted schematically on cross section A-A' to include
surface deposits and underlying, older basin fill. Three surface units (Qp2-4) are
differentiated on the map (unit Qp1 is present north of the map area in the vicinity
of South Mountain).
Qa
Qp3
&wp
Qa
Qp
Qa
Qp3
Qp3
3
Colluvium mantling side slopes of drainages on the Estancia basin piedmont
slope (Late Pleistocene (?) to Holocene) — Derived from erosion of piedmont
surface deposits and older, basin-fill deposits. Includes unmapped deposits of units
Qp 2-4 and older basin fill, and interfingers with valley-floor alluvium (Qa) along
drainage foot slopes. Unit is estimated to be less than 5 m thick.
Qc
Qa
Qp
4
Qc
Qc
Qc
Qa
Qp
Qc
Qc
&ws
4
Qa
Qp
Qp
o
o
2
)
Qc
Qc
Holocene
Qp3
&ws
Qa
Qvac
Qc
Late Pleistocene
Qp
Qa
Middle Pleistocene
Qa
Qp
&ws
Qp2
Qc
The Edgewood 7.5-minute quadrangle is located approximately 40 km east of
Albuquerque, NM along the eastern side of the Manzanita Mountains (see location map).
The town of Edgewood, which lies along Interstate Highway 40, is located on the
quadrangle. About half of the map area is underlain at relatively shallow depths by
sedimentary rocks consisting of limestone, shale, and sandstone of the Pennsylvanian
Madera Group. Bedrock uplands are generally covered by stands of pinyon and juniper and
thin to moderately deep, well-drained soils form an extensive cover over many upland areas
shown as bedrock on the map. The northeastern part of the quadrangle is underlain by up to
several tens of meters of valley- and basin-fill alluvium of the Estancia basin, and is
dominated by grass cover. No perennial streams flow through the map area and water for
stock and domestic use is dependent on groundwater supplies. Average annual precipitation
for the area is on the order of 12 inches (~30cm.).
Late
Qvac
3
AW
Qa
Valley-floor alluvium (Holocene) — Predominantly silt, sand, and clay in modern
drainage channels and underlying floodplains. Coarser grained materials occur in
some areas. Unit is inset into unit Qp and older deposits of unit Qvac, and
interfingers with younger deposits of units Qvac and Qc along drainage foot slopes.
Includes unmapped bedrock exposures in scoured channel reaches. Unit is
generally less than 3 m thick.
Middle
U
D
Qa
Qa
Qc
&ws
&ws
Qvac
G
Qp3
9
Qvac
IN
Quaternary
Qc
Qp2
Correlation of Map Units
Quaternary
o
Geologic Discussion
Description of Map Units
Qa
Qc
Qa
Qc
Qp2
Qcr
Qcr
6
Qc
Qp
&wp
o
Qa
Pennsylvanian
Qp3
CENOZOIC
&ws
&ws
106º07'30"
35º07'30"
R. 8 E.
Qa
Qc
PALEOZOIC
Qvac
3887000m.N.
Qp
Qp
Qp3
PROTEROZOIC
o
5
R. 7 E.
10'
(SAN PEDRO)
(K
12'30"
&ws
6.3 MI TO N. MEX. 44
MORIARTY 13 MI.
K)
R. 7 E.
NEW MEXICO
SAN PEDRO 12 MI.
CEDAR GROVE 3.1 MI.
(MORIARTY NORTH)
R
PA
R. 6 E.
87000m.E.
R
D
B3
D
AN
106º15'
35º07'30"
Ti
St jer
ru as
ct -G
ur ut
al ie
Zo rre
ne z
(S
EDGEWOOD QUADRANGLE
&ws
&s
&m
Xu
&wp
6,000’
&s
Xu
5,000’
5,000’
B
B'
8,000
feet ASL
&wp
7,000’
Strike and dip of inclined bedding.
&wp
&ws
&s
Juan Tomas
Canyon
&ws
&m
&m
&s
&wp
&ws
&m
&wp
&wp
&wp
&ws
&s
&m
&wp
&wp
&ws
&m
&wp
&s
&m
5,000’
Xu
Xu
Xu
Xu
8,000
feet ASL
7,000’
&ws
6,000’
Xu
Arroyo de
San Jose
&s
6,000’
Xu
Note: Faults shown as vertical where attitude is unknown. Arrows indicate relative vertical displacement.
5,000’