NEW MEXICO BUREAU OF GEOLOGY AND MINERAL RESOURCES
105°45'0"W
433000
434000
36°37'30"N
A DIVISION OF NEW MEXICO INSTITUTE OF MINING AND TECHNOLOGY
435000
105°42'30"W
436000
437000
438000
B' A
439000
105°40'0"W
440000
441000
442000
443000
444000
Qls
Qal
Tucem
Qal Qfy
Qfy
Tv
36°37'30"N
Qfy
4053000
Surficial Deposits
4053 000
Qls
QTg
Tb
Tb
Tucem
QTrg
Tb
Qfy
Tg
Tg
Qal Stream channel and valley-floor alluvium, and active floodplains (Holocene)
- poorly to well-sorted, poorly sorted sand, pebbles, and boulders; clasts of
granitic, metamorphic, volcanic, and sandstone rock types; clasts along Rio
Hondo dominated by granitic rock types, quartzite and basalt; clasts along
tributaries draining the western side of the Rio Grande dominated by volcanic
rock types.
Qal
Qfy
Qls
QTrg
4052000
4052 000
Qfy
Qls
Qal
QTg(sc)
Tg
Qfy
Qfv
Tb
Qfu
Tg
Qls
4051000
Qal
Qal
Qt7a
Qt6
Qfu
Qfy
4051 000
Qls Landslide deposit (late Pleistocene to Holocene) - poorly sorted sand to
boulders, includes large rotational slide blocks within the Rio Grande gorge,
which include large, rotated and detached beds of Servilleta Basalt (Tb)
Qt7
Qt1rg
Qfu
Qfy
Qfy
4050000
Qfy Qty: Young alluvial-fan and stream terrace deposits (latest Pleistocene to
Holocene) - poorly sorted silt, sand, pebbles, cobbles, and boulders; clasts
primarily of quartzite, schist, granite, and volcanic rock types; associated soils
have stage I calcium carbonate development; includes unit Qt8 of Kelson (1986).
QTg
Qls
Qal
4050 000
Tv
Tv
QTg
Qt7
Qfu
Qfy
Qfy
Qal
QTg
Qal
Qt2
Qt7 Stream terrace deposits (early to middle Holocene) - poorly sorted silt, sand,
pebbles, cobbles, and boulders; clasts primarily of quartzite, schist, granite, and
volcanic rock types; associated soils have stage I calcium carbonate
development.
Qfy
Tb
Qfy
Qfy
4049000
4049 000
QTg
Qt2
Tv
36°35'0"N
Tg
Qfy
Qfv
Qto
Qt6 Stream terrace deposits (latest Pleistocene) - poorly sorted silt, sand,
pebbles, cobbles, and boulders; clasts primarily of quartzite, schist, granite, and
volcanic rock types; associated soils have stage I to II calcium carbonate
development.
36°35'0"N
Tv
Qfy
Tg
QTg
4048000
4048 000
Tg
Tg
Qt4 Stream terrace deposits (middle to late Pleistocene) - poorly sorted silt, sand,
pebbles, cobbles, and boulders; clasts primarily of quartzite, schist, granite, and
volcanic rock types; associated soils have stage III calcium carbonate
development, argillic Bt soil horizons and 10YR to 7.5YR hues in Bt horizons.
Qfy
Qfy
QTrg
4047000
QTg
Tb
Qfy
Qt1rg
Qt2rg
Qfy
Qal
Td
Qt7
Qt2
4047 000
Qt1rg
Td
Qt2rg
4046000
4046 000
Qal
Qt1rg
Qfy
Qfy
Qal
Td
Qal
4045000
QTg
Qfu Undifferentiated alluvial fan deposits (middle to late Pleistocene) - probably
correlative with stream units Qt2 through Qt6; poorly sorted silt, sand, pebbles,
and cobbles; not correlated to other fan units because of lack of well-defined age
control, clear stratigraphic position, and distinct lithologic characteristics.
QTg
Qt1rg
QTrg Stream gravel deposited by ancestral Rio Grande (late Tertiary? to
middle? Pleistocene) -poorly sorted sand, pebbles, and cobbles; clasts of
basalt, quartzite, slate, schist, other metamorphic rock types, and volcanic rock
types; very rare Amalia Tuff clasts; associated with broad, highest terrace west of
Rio Grande; upper soil horizons commonly affected by surface erosion; locally
mantled by eolian sand.
Qt3 Stream terrace deposits (middle to late Pleistocene) - poorly sorted silt, sand,
pebbles, cobbles, and boulders; clasts primarily of quartzite, schist, granite, and
volcanic rock types; associated soils have stage III calcium carbonate
development, argillic Bt soil horizons and 10YR to 7.5YR hues in Bt horizons.
QTg
Qty
4045 000
Qfy
Qal
36°32'30"N
C
4044000
QTg
Tb
Qt1rg
Tb
Qfy
Qal
Qfy
Qfy
Qt3
Qt1rg
Qt3
Qt3
QTg
Qal
Qfy
Qt2rg
Qt4
Qt5
Qt6
Qt6
Qt5
Qfy
Qt8
Qt1rg
Qt5
Qt4
Tb
Qfy
Qt6
Qal
Qfy
Qt7
Qfy
Qt4
Qfy
Qfy
Qfy
QTbh
Qt7
Qfy
Qt5
Qt8
Qt6
QTbh
Qt2
of Blueberry Hill, thickness exceeds 25 m; may be considerably more; deposit
may interfinger with unit QTg and QTrg; correlative with “Basin Fill deposit” of
Kelson (1986).
Tv
Qt5
Qfy
QTbh
Qf1
QTbh
Qt4
QTbh
QTbh
Qt6 QTbh
Qfy
Qfy
Qt5
Qt5
C'
4043
Correlation Chart for the Arroyo Hondo Quadrangle, Taos County, New Mexico
000
Qf1
Trib. Valleys
Piedmont
Qty
Qt7
Qfy
latest Pleist
Qt6
Qfu
late Pleist
Qt5
QTbh
Qfy
Holocene
Qal
Qfy
4042000
Qls
Qfy
Qfy
Qt1rg
Qfy
4042 000
Qf1
Qfy
Qty
QTbh
D'
Qt2rg
Qt4
QTbh
middle Pleist
Qt1rg
Qt1rg
Qt3
Qt1rg
Qt2
4041000
Qt2rg
4041 000
Qfy
Qt1rg
early Pleist
Qty
Qfy
Qty
Qal
433000
434000
105°45'0"W
435000
436000
105°42'30"W
Qal
Qal
437000
Qal
438000
439000
A'
440000
105°40'0"W
1:24,000
TRES PIEDRAS NE
1
QUESTA
NEW MEXICO
CERRO
DE LOS
TAOSES
TRES
OREJAS
Arroyo
ARROYO
HONDO
Hondo
LOS CORDOVAS
ARROYO
SECO
TAOS
0.5
980
0
1
Magnetic Declination
May, 2006
9º 33' East
At Map Center
0
980
1960
0.5
2940
1 MILE
3920
4900
0
5880
441000
442000
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
Tg
Tv
Intermediate volcanic rocks (Pliocene) - undifferentiated
Qal
443000
Qf1
Qal
36°30'0"N
444000
105°37'30"W
Geologic map of the Arroyo Hondo
quadrangle, Taos County, New Mexico.
6860 FEET
May 2006
1 KILOMETER
by
Keith Kelson and Paul Bauer 2
1
CONTOUR INTERVAL 40 FEET
NATIONAL GEODETIC VERTICAL DATUM OF 1929
1
QUADRANGLE LOCATION
Tv
QTg (north of Rio Hondo)
QTbh (south of Rio Hondo)
Qf1
QTbh
Qty
Base map from U.S. Geological Survey 1963, from photographs taken 1962, field checked in 1963.
1927 North American datum, UTM projection -- zone 13N
1000-meter Universal Transverse Mercator grid, zone 13, shown in red
GUADALUPE
MOUNTAIN
Tb
New Mexico Bureau of Geology and Mineral Resources
Open-file Map Series
7700
7600
William Lettis and Associates, 1777 Botelho Dr., Suite 262
Walnut Creek, CA, 94596
2
NMBGMR, 801 Leroy Pl., Socorro, NM, 87801
A
7500
OFGM 116
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).
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
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.
QTg
7300
7700
7600
7400
COMMENTS TO MAP USERS
10x vertical exaggeration
Arroyo Hondo Quadrangle: A-A’’
Garrapata Canyon
Qfv
36°30'0"N
Qty
QTbh
Qal
QtyQty
Garrapata Ridge
D
Servilleta Formation, interbasalt gravel (Pliocene) - Sedimentary intervals
between basalt flow members (Leininger, 1982), as much as 180 m thick in
northern part of quadrangle, as exposed in the Rio Grande and Rio San Cristobal
gorges.
Pliocene
4040 000
Qt1rg
A‘’
By Keith Kelson and Paul Bauer
7500
May, 2006
7400
QTg
Tb
7300
Tb
Elevation
(feet)
4040000
Tg
Qal
Qty Qty
Cross section B-B’’
Qty Qty
Qf1
QTrg
Qty
Qty
Qty
Qt2
Qt1rg
Qf1
Qfy
Tertiary Rocks
Tb
Servilleta Formation, basalt (Pliocene) -Dark-gray, diktytaxitic olivine tholeiite
that forms thin, fluid, widespread pahoehoe basalt flows of the Taos Plateau
volcanic field. These flows commonly form columnar-jointed cliffs in the Rio
Grande Gorge. Tabular plagioclase and sparse olivine are the only phenocrysts.
Individual flows, which are up to 12 m thick, are grouped into packages of from
one to ten flows (Peterson 1985; Dungan et al., 1984). These packages are
separated by sedimentary intervals that are as much as 5 thick in southern part
of quadrangle, but as much as 180 m thick in northern part of quadrangle
(Leininger, 1982). Five central volcanic vents to the north are sources for the
Servilleta Formation (Lipman and Mehnert, 1979). 40Ar/39Ar ages from basalts
exposed in the Rio Grande gorge range in age from 4.81 +/- 0.03 Ma for the
lowest basalt near the Gorge Bridge, to 3.12 +/_ 0.13 Ma for the highest basalt
flow at the Gorge Bridge (Appelt, 1998).
Qal
Rio Grande
Qt6
Qt6
Qfy
Qfy
Qt7
Qt8
000
36°32'30"N
4044
Qt7
Qfy
4043000
Qt8
Qfy
Qt8
Qfy
Qt2
Qt4
Qt7 Qfy
Qfy
Qt3
Qt5
Qt6
Qfy
Qt6
Qfy
Qt3
Qt4?
Qt4
QTg
Qt5
Qt7 Qfy Qt6 QTbh
Qt5
Qt7
Qfy
Qt7
Old alluvium (late Tertiary? to middle? Pleistocene) - poorly sorted sand,
pebbles, and cobbles; clasts of basalt, quartzite, slate, schist, other metamorphic
rock types, and volcanic rock types; locally high percentage of angular to
subangular quartzite pebbles and cobbles; may be correlative with Blueberry Hill
deposit; present along piedmont between Sangre de Cristo range front and Rio
Grand gorge north of Rio Hondo; correlative with Lama Formation of Lambert
(1966); contains ash layer in roadcut near Cerro Negro (UTM 439989, 4044603)
QTbh Blueberry Hill deposit (late Tertiary? to middle Pleistocene) - poorly
sorted silt, sand and pebbles; commonly cross-bedded, and stained with black
manganese oxide and yellowish-orange iron oxide coatings; oxidized; clasts are
weathered or grussified; contains distinct discontinuous sandy interbeds; clasts
are granitic rock types, quartzite, metamorphic rock types, and volcanic rock
types; commonly crudely imbricated; imbrication suggests westerly flow direction
in area north of Taos Municipal Airport; based on exposures at southwestern end
Td
Qfy
Alluvial fan deposits (middle Pleistocene) - poorly sorted silt, sand, and rare
pebbles; clasts primarily of granitic, intermediate volcanic, basalt, and
metamorphic rock types; stage III and IV calcium carbonate development where
preserved, although soil horizons are commonly affected by surface erosion;
correlative with Unit Q1p of Kelson (1986); ash probably within Qf1 deposits at
locality on Ranchos de Taos quadrangle near Stakeout Road dated at 1.27
Ma (40Ar-39Ar method, W. McIntosh, personal communication, 1996); deposit is more
than 5 m thick in northeastern part of quadrangle, and is thinner from northeast to
southwest; differentiated from unit QTbh by larger clast size (Kelson, 1986), less
oxidation, poor sorting, absence of abundant manganese oxide staining, and
clasts that are less weathered.
Qt1rg Stream terrace deposits flanking Rio Grande (middle Pleistocene) poorly sorted silt, sand, pebbles, and boulders; clasts of basalt, quartzite, slate,
schist, other metamorphic rock types, volcanic rock types, and (rarely) sandstone
and limestone; locally may contain clasts of Tertiary Amalia Tuff; where
preserved, associated relict soils have stage III to IV calcium carbonate
development, thick argillic Bt soil horizons, and 7.5YR hues in soil Bt horizons;
upper soil horizons commonly affected by surface erosion; may be mantled
locally by unit Qe.
Qt5 Stream terrace deposits (late Pleistocene) - poorly sorted silt, sand, pebbles,
cobbles, and boulders; clasts primarily of quartzite, schist, granite, and volcanic
rock types; associated soils have stage II to III calcium carbonate development.
Qal
Qt2
Qf1
Qt6
QTg
Stream terrace deposits (middle Pleistocene) -poorly sorted silt, sand,
pebbles, cobbles, and boulders; clasts primarily of quartzite, schist, granite, and
volcanic rock types; associated soils have stage III to IV calcium carbonate
development; associated soils have stage III to IV calcium carbonate
development, thick argillic Bt soil horizons, and 7.5YR to 10YR hues in soil Bt
horizons; upper soil horizons locally affected by surface erosion.
Qt2rg Stream terrace deposits flanking Rio Grande (middle Pleistocene) poorly sorted silt, sand, pebbles, and boulders; clasts primarily of granitic,
metamorphic, intermediate volcanic, basalt, and sedimentary rocks; locally may
contain clasts of Tertiary Amalia Tuff; associated soils have stage III to IV
calcium carbonate development, thick argillic Bt soil horizons, and 7.5YR to
10YR hues in soil Bt horizons; upper soil horizons locally affected by surface
erosion; may be mantled locally by unit Qe; possibly faulted along the Dunn fault.
Qc Colluvial mantle on slopes, undifferentiated (middle Pleistocene to
Holocene) - poorly-sorted sand, pebbles and boulders; prevalent along bases of
mountain-front facets; in northwestern part of quadrangle (west of Rio Grande),
thin mantle overlying volcanic bedrock.
Tg
QTg
Tb
Qls
Qfy
Qt2
Qls
Tv
B
NMBGMR Open-file Map Series
OFGM 116
Last Modified 30 November, 2010
Unit Descriptions for Arroyo Hondo, NM Quadrangle
Keith Kelson and Paul Bauer
May 2006
105°37'30"W
7200
7200
Tg
Tg
7100
Tb
7100
QTg
Qal
7000
Qal
QTg
Qal Tg
QTg
Qfl
Qal
QTbh
Qt3
QTbh
Qt4
Qt6
Tg
6700
Tv
6900
Qfy
Qt5
6800
Qfl
7000
Qfy
Qal
6900
Qal
Qfl
Qt7
Qt6
6800
Qal
Tv
6700
Tb
6600
6600