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Articles 181 - 210 of 318
Full-Text Articles in Geology
Stratigraphic Analysis Of Pennsylvanian Strata In The Lucero Region Of West Central New Mexico., James L. Martin
Stratigraphic Analysis Of Pennsylvanian Strata In The Lucero Region Of West Central New Mexico., James L. Martin
Earth and Planetary Sciences ETDs
During Pennsylvanian time the Lucero region of west central New Mexico was located along the southeastern part of the Zuni uplift and along the western and central part of the Lucero basin. The Lucero basin is part of the broad Pennsylvanian seaway that extended north-northwestward through central New Mexico to the Paradox basin on the north and the Orogrande basin on the south. Positive elements associated with the Lucero basin were the Zuni uplift to the west, the Penasco-Uncompahgre uplifts to the northeast, the Joyita uplift. to the east,. and the Pedernal uplift farther to the east.
The Pennsylvanian strata …
Petrology And Structure Of Eastern Monte Largo Hills, New Mexico, Jan Ralph Huzarshi
Petrology And Structure Of Eastern Monte Largo Hills, New Mexico, Jan Ralph Huzarshi
Earth and Planetary Sciences ETDs
In the Monte Largo Hills in the central part of north-central New Mexico, Precambrian metamorphic and igneous rocks, Paleozoic sediments, and Tertiary intrusive and extrusive igneous rocks occur. The metamorphics consist of a series of quartzo-feldspathic gneiss, mica schist, metaquartzite, and hornblende schists. These rocks were
derived from Precambrian sediments, mostly sandstones, arkoses and impure dolomites that were subjected to amphibolite facies synkinematic metamorphism. The Precambrian alkali granite appears to have been allochthonously emplaced with evidence near the contact of the quartzofeldspathic metamorphics for a parautochthonous formation. Quartz veins and pegmatite dikes of Precambrian age are also present. The sediments …
Geology Of The Hogback Mountain Area, Northern Big Belt Mountains, Montana., William L. Shaffer
Geology Of The Hogback Mountain Area, Northern Big Belt Mountains, Montana., William L. Shaffer
Earth and Planetary Sciences ETDs
The Hogback Mountain area is located in the northern part of the Big Belt Mountains, twenty miles northeast of Helena, Montana.
Sedimentary rocks range in age from Precambrian to Recent, and have an aggregate thickness of about 16, 500 feet. The oldest stratified rocks are two conformable formations of the Precambrian Belt Series; the Newland Formation (oldest) and the Greyson Shale. These rocks have an aggregate thickness of about 10,700 feet.
Rocks of the Belt Series are unconformably overlain by about 1,200 feet of strata of Middle and Late Cambrian age separated into five conformable formation: the Flathead Sandstone (oldest), …
Regressive And Transgressive Phenomena In The Gallup Sandstone In The Northwestern Part Of San Juan County, New Mexico., Francis Amrisar Kaharoeddin
Regressive And Transgressive Phenomena In The Gallup Sandstone In The Northwestern Part Of San Juan County, New Mexico., Francis Amrisar Kaharoeddin
Earth and Planetary Sciences ETDs
The sedimentary history of the Gallup Sandstone is studied through the field investigation and laboratory analysis of samples taken from four measured sections in the vicinity of the San Juan River and one section near the Red Rock Highway. In addition to field data, textural parameters and dolomite and glauconite content of sandstone samples are the basis for interpretations of the sedimentary history and environment of deposition of the Gallup Sandstone.
A plot of the mean grain-size and sorting along with stratigraphic sections reveals that most of the Gallup Sandstone was deposited in a regressive sea, and that the regression …
Geology, Geochemistry And Lava Tubes In Quaternary Basalts, Northeastern Part Of Zuni Lava Field, Valencia County, New Mexico, James Douglas Causey
Geology, Geochemistry And Lava Tubes In Quaternary Basalts, Northeastern Part Of Zuni Lava Field, Valencia County, New Mexico, James Douglas Causey
Earth and Planetary Sciences ETDs
Basaltic volcanism in the northeastern part of the Zuni lava field is related to a north-northeast trending regional fracture system. This is shown by elongation of centers and their alignment. However, .the fractures do not control the direction of lava tubes.
There are three distinct stages of volcanic activity common to the Zuni lava field:
1) early pyroclastic eruptions,
2) quiescent flows or fissure eruptions
3) late pyroclastic eruptions.
Evidence for the first stage is sometimes lacking, but the second and third stages can always be seen.
The basalts range from weakly tholeiitic to alkali in nature. Potassium content varies …
Effect Of The Pedernal Axis On Permian And Triassic Sedimentation, Philip F. Hock
Effect Of The Pedernal Axis On Permian And Triassic Sedimentation, Philip F. Hock
Earth and Planetary Sciences ETDs
The area surrounding the Pedernal Hills has been of scientific and economic interest for a number of years. The effect of the Pedernal axis on sedimentation and stratigraphy of late Paleozoic rocks is of major importance. The principal purposes of this study were to determine whether the Precambrian terrane was an active source of sediment and what effect it had on thickness of strata during Permian and Triassic time. the area was also mapped in as much detail as the scale (1:125,000) permitted.
Surface Energies In The Caso4-H2o System And The Effect Of Supersaturation On The Crystallization Of Gypsum, Sandra C. Feldman
Surface Energies In The Caso4-H2o System And The Effect Of Supersaturation On The Crystallization Of Gypsum, Sandra C. Feldman
Earth and Planetary Sciences ETDs
The surface energy of gypsum has been experimentally determined to be 70. 2 erg/cm2 at 30˚ C. The value for anhydrite is calculated as 112 erg/cm2. At various extrapolated supersaturations, the number of particles or ions necessary to form nuclei of gypsum and anhydrite is:
Supersaturation
No. part. or ions/nucleus
Gypsum
Anhydrite
10
60.5
1000
51
8
2
99
20
4
Crystal size measurements and crystal shapes were noted for gypsum within the range of supersaturations studied (45.6 to 131). The maximum crystal size is attained at a slightly lower supersaturation than the critical supersaturation. The shape …
Crystal Structures Of Potassium Ferric Sulfate Minerals., Edward J. Graeber
Crystal Structures Of Potassium Ferric Sulfate Minerals., Edward J. Graeber
Earth and Planetary Sciences ETDs
The potassium ferric sulfate minerals, yavapaiite [KFe(so ) J and goldichite [KFe(so4) •4H2oJ were studied 42 2 using x-ray diffraction methods, and the results correlated with the mineral krausite [KFe(so4)2 ·H20J .
Yavapaiite crystallizes in space group C2/m with two formula weights in a unit cell of dimensions a= 8 .152A, b = 5, 153A, c = 7,877A and S = 911.70°. Goldichite , in space group P2 /c, contains four formula weights in a unit cell with a= 10 . 387A, b = 10.486A, c = 9.086A and 6 = 101.67°.
The structures were solved by three-dimensional Patterson syntheses …
Trace-Element Geochemistry Of Southwestern Turquoise, Anne Marguerite Colberg Sigleo
Trace-Element Geochemistry Of Southwestern Turquoise, Anne Marguerite Colberg Sigleo
Earth and Planetary Sciences ETDs
Southwestern turquoise (CuAl6(PO4)4 OH8 · 4H2O) is associated with Laramide intrusions along the eastern and southern margins of the Colorado Plateau in Colorado, New Mexico, and Arizona, and with a zone of Late DevonianMississippian tectonic activity in Nevada. A review, of the previous work on the origin of turquoise is presented. Of these, the supergene hypothesis proposed by Sidney Paige in 1912 generally remains undisputed in the literature. Much of the data presented in this study, however, suggest a hydrothermal mode of formation. The concentrations of Co in particular are most similar …
Volcanic Rocks Associated With The Western Part Of The Mogollon Plateau Volcano-Tectonic Complex, Southwestern New Mexico, Rodney Charles Rhodes
Volcanic Rocks Associated With The Western Part Of The Mogollon Plateau Volcano-Tectonic Complex, Southwestern New Mexico, Rodney Charles Rhodes
Earth and Planetary Sciences ETDs
An area of approximately 450 square miles was mapped on a reconnaissance basis, covering part of the western half of the Mogollon Plateau volcano-tectonic complex. This report deals with the geology of the area and its relationship to the regional volcano-tectonic structure of the Mogollon Plateau.
Flow Direction Of Volcanic Rocks In The Northern Part Of The Mogollon-Datil Province, New Mexico, Glenn Alan Krimsky
Flow Direction Of Volcanic Rocks In The Northern Part Of The Mogollon-Datil Province, New Mexico, Glenn Alan Krimsky
Earth and Planetary Sciences ETDs
The northern part of the Mogollon-Datil province is located on the margin of the mid-Tertiary volcanic province of southwest New Mexico. The techinique established b Smith (1967) for determining flow direction of volcanic rocks was applied, for the first time, to determine flow direction and source areas of volcanic rocks form uncertain centers.
The Lower volcanic Group, which contains thick sequences of rhyolltes, latites, and andesites between 38 and 29 m.y. old, originated from two volcanic centers. Source area for the Datil formation, comosed of the Spears and Hells Mesa Members, is in the northern San Mateo Mountains. The Tda …
Effective Rates Of Evaporation And Chemical Properties Of The Precipitates., John Lincoln Rasho
Effective Rates Of Evaporation And Chemical Properties Of The Precipitates., John Lincoln Rasho
Earth and Planetary Sciences ETDs
An experiment was designed to simulate the evaporation of sea water in the laboratory. The experiment was conducted isothermally at 35 1. Chlorinity, salinity, and density of the solution were determined at different stages of evaporation. Also the trace element contents of Sr, Rb, K, and Li of the precipitates were determined to study the possible changes, and the significance of these changes, in the concentration of these trace elements in solution at different stages of evaporation.
The results of this experiment and the work of previous investigators indicate that the rate of crystallization from sea water, at any given …
Stratigraphic Analysis Of The Upper Permian And Lower Triassic Strata In Southern Utah, Charles Dennis Irwin Jr.
Stratigraphic Analysis Of The Upper Permian And Lower Triassic Strata In Southern Utah, Charles Dennis Irwin Jr.
Earth and Planetary Sciences ETDs
Permian sedimentation in southwestern Utah was influenced by three principal depositional areas. These areas were the Oquirrh basin in north-central Utah, the Cordilleran geosyncline in eastern Nevada, and the Quemado-Cuchillo basin on the northern shelf of the Sonoran geosyncline in east-central Arizona and west-central New Mexico. Throughout Permian time, marine sediments and their well-developed beach and continental eolian sandstone equivalents were deposited within these basins and upon their surrounding shelves. Each of the three basins appear to have exerted their influence upon sedimentation during a discrete period of geologic time. Thus while one basin was sedimentationally active the other two …
Geology Of Part Of The Creston Range, Mora County, New Mexico, Tim T. Schowalter
Geology Of Part Of The Creston Range, Mora County, New Mexico, Tim T. Schowalter
Earth and Planetary Sciences ETDs
The low hills and hogback ridges of the Creston Range form the southeastern edge of the Sangre de Cristo Mountains.
Rocks ranging from Precambrian to Quaternary are exposed in the Creston Range. The Precambrian rocks consist of generally foliated, medium-grade metamorphics intruded by concordant, simple pegmatites. These rocks have been subjected to at least two episodes of deformation of Precambrian age. Approximately 9,000 feet of sedimentary rocks of Devonian (?)-Mississippian to Permian age that were deposited in an intracratonic basin to shelf environment are present. Tertiary-Quaternary rocks are represented by outliers of a basalt flow from the Ocate colcanic field …
Effect Of Supersaturation On The Kinetics Of The Gypsum-Anhydrite Transition., Pao-Chin Chao
Effect Of Supersaturation On The Kinetics Of The Gypsum-Anhydrite Transition., Pao-Chin Chao
Earth and Planetary Sciences ETDs
Gypsum and anhydrite have been found extensively in evaporite beds. Gypsum is the low-temperature, hydrous form of calcium sulfate, while anhydrite is the high-temperature, anhydrous form. The temperature of gypsum-anhydrite transition has been fixed, by both solubility measurements and thermodynamic calculations, in the range of 38 to 42°c in pure water; and at lower values with increasing NaCl content in the solutions. However, the precipitation of anhydrite has never been obtained experimentally in its own stability field, gypsum is always metastably formed instead.
Many investigators believe that the primary precipitation of anhydrite from solutions is improbable. It is usually converted …
Igneous Geology Of The Rio Puerco Necks, Sandoval And Valencia Counties, New Mexico., William Travis Brown Jr.
Igneous Geology Of The Rio Puerco Necks, Sandoval And Valencia Counties, New Mexico., William Travis Brown Jr.
Earth and Planetary Sciences ETDs
In the Rio Puerco valley of Valencia and Sandoval Counties, New Mexico, immediately east of Mount Taylor and its associated lava flows are a series of ten prominent and exposed basaltic rocks. These bodies consist of alkali basalts exhibiting no systematic mineralogic or compositional trends throughout the area. The alkali basalts are composed of olivine, augite, plagioclase (labradorite), and opaques in a trachytic to felty groundmass. Each neck was emplaced by means of a convection cell mechanism that allowed the surrounding Cretaceous sediments to remain undisturbed by the intrusion. Contained in the alkali basalts are ubiquitous ultramafic inclusions of lherzolite …
Geology Of The Southern San Mateo Mountains, Socorro And Sierra Counties, New Mexico, Steven Eugene Farkas
Geology Of The Southern San Mateo Mountains, Socorro And Sierra Counties, New Mexico, Steven Eugene Farkas
Earth and Planetary Sciences ETDs
The San Mateo Mountains of south-central New Mexico consist of a series of uplifted blocks of Tertiary volcanic rocks which cover an area approximately 45 miles long by 20 miles wide. Faulted blocks of older, Paleozoic and Precambrian, rocks and post-volcanic intrusives are found along the eastern and southern borders of the range. Only late Paleozoic, Pennsylvanian and Permian sediments occur in the mapped area. More than 7,000 feet of Tertiary volcanic rocks unconformably overlies all older rocks, divided into the Lower Volcanic and Datil Groups. The lower Volcanic Group is composed of a series of deeply altered andesites, tuffaceous …
Stratigraphy And Structure Of The Northwestern Guadalupe Mountains, New Mexico, Klyne Headley
Stratigraphy And Structure Of The Northwestern Guadalupe Mountains, New Mexico, Klyne Headley
Earth and Planetary Sciences ETDs
The northwestern Guadalupe Mountains of southeastern New Mexico are part of a large regional cuesta that slopes gently northeast. The crest of the northern escarpment rises abruptly to more than 2,200 feet above Pinon Valley.
The rugged west-facing escarpment has been carved in an uplifted fault block composed entirely of Permian sedimentary rocks having an aggregate thickness of about 1,700 feet. Dark-red to buff siltstone, gray dolomite, and white to gray gypsum compose the Yeso Formation. Conformably overlying these rocks is the dark-brown limestone and dolomite sequence of the San Andres Formation. The Glorieta Sandstone which usually occurs between these …
Origin Of Reeflike Masses In The Upper Member Of The San Andres Formation, Central Guadalupe Mountains, Eddy County, New Mexico, Richard Lane Squires
Origin Of Reeflike Masses In The Upper Member Of The San Andres Formation, Central Guadalupe Mountains, Eddy County, New Mexico, Richard Lane Squires
Earth and Planetary Sciences ETDs
Several reeflike masses crop out in the upper part of the Upper member of the San Andres Formation in the Last Chance Canyon area, southeastern New Mexico. The reeflike masses are situated on the Northwest shelf adjacent to the Delaware basin of Permian age. Based on the compilation of the field and laboratory data, it was concluded that the reeflike masses are not reefs at all and such exposures are termed pseudoreefs. No criteria were found which could be used to differentiate the masses from surrounding, laterally equivalent strata since both consist of relatively unfossiliferous dolomitized mudstones and wackestones. The …
Petrography And Structure Of The Pedernal Hills, Torrance County, New Mexico, Ralph Alan Gonzales
Petrography And Structure Of The Pedernal Hills, Torrance County, New Mexico, Ralph Alan Gonzales
Earth and Planetary Sciences ETDs
In the Pedernal Hills, in the eastern part of north-central New Mexico, five Precambrian metamorphic and igneous rock types occur. Stratigraphically, oldest to youngest, they include medium-grained granite gneiss; quartzite, quartz-mica schist, and quartz-specular hematite schist; schist unit consisting mainly of quartz-muscovite schist and greenstone; intrusive granite which includes rocks ranging from quartz diorite to alkali granite; and cataclasite representing dynamically metamorphosed rocks.
The Geology Of The Jicarilla Mountains, Lincoln County, New Mexico., George Ernest Ryberg
The Geology Of The Jicarilla Mountains, Lincoln County, New Mexico., George Ernest Ryberg
Earth and Planetary Sciences ETDs
The Jicarilla Mountains in west-central Lincoln County, New Mexico, consist of Permian, Triassic, and Cretaceous sediments intruded by Tertiary sills, dikes, laccoliths, and stocks. The upper 50 feet of the Yeso Formation is exposed and is conformably overlain by the San Andres Formation which consists of the lower Sandstone, and middle Limestone, and upper Gypsum members. The Permian Artesia Formation, which is about 300 feet thick, unconformably overlies the Gypsum member. Unconformably overlying the Artesia Formation is a 200-foot section of the Triassic Santa Rosa Formation. The boundary between the Santa Rosa Formation and the overlying Chinle Formation is gradational. …
The Geology Of The White Oaks-Patos Mountain Area, Lincoln County, New Mexico, Richard A. Haines
The Geology Of The White Oaks-Patos Mountain Area, Lincoln County, New Mexico, Richard A. Haines
Earth and Planetary Sciences ETDs
The White Oaks-Patos Mountain area is in the north central portion of the Sierra Blanca basin in central Lincoln County, New Mexico. The rocks consist of Permian, Triassic, and Cretaceous strata intruded by early Tertiary sills, dikes, and laccoliths. The 2,900 feet of sedimentary strata include 750 to 800 feet of Permian rocks, 550 feet of Triassic rocks, and 1700 feet of Cretaceous rocks. Extensive Tertiary Quaternary pediments cover much of the area.
The mapped area lies in the center of a large concentration of Tertiary intrusive bodies known as the ln County porphyry belt, including Patos Mountain. Igneous rocks …
Geology Of The Southern Pilot Range, Elko County, Nevada And Box Elder And Tooele Counties, Utah, John Michael O'Neill
Geology Of The Southern Pilot Range, Elko County, Nevada And Box Elder And Tooele Counties, Utah, John Michael O'Neill
Earth and Planetary Sciences ETDs
The southern Pilot Range is a slightly sinuous, north-trending mountain range located in the northeastern part of the Great Basin.
Approximately 18,500 feet of miogcosynclinal sedimentary rocks representing every system from late Precambrian to Permian(?) are exposed in the southern Pilot Range. Because of intense faulting, many of the stratigraphic relationships between the formations are impossible to determine. Mesozoic and Tertiary strata are absent; however, Pleistocene Lake Bonneville deposits are wide spread, although thinly distributed. Small igneous stocks, dikes, and sills are common only in the southern two-thirds of the map area. Stocks are principally granodioritic. In several cases the …
Structure And Stratigraphy Of The Northern Part Of The South Virgin Mountains, Clark County, Nevada, J. R. Morgan
Structure And Stratigraphy Of The Northern Part Of The South Virgin Mountains, Clark County, Nevada, J. R. Morgan
Earth and Planetary Sciences ETDs
The northern part of the South Virgin Mountains is within the transition zone between the Basin and Range Province and the High Plateaus of the Colorado Plateau. Sedimentary formations in the Paleozoic are represented by more than 6,800 feet of carbonate and elastic sediments. Ordovician rocks are thought to be present, but are not confirmed. Rocks of Silurian age are absent from the area. Triassic and Jurassic units, the Moenkopi Formation, Chinle Formation and the Aztec Sandstone, have a composite thickness of more than 3,700 feet. There are elastic and minor carbonate rocks, all of continental origin, that are of …
Criteria For The Determination Of Flow Direction In Volcanic Rocks, Eugene Irwin Smith
Criteria For The Determination Of Flow Direction In Volcanic Rocks, Eugene Irwin Smith
Earth and Planetary Sciences ETDs
A statistical method employing the Tukey Chi-square test and the vector method was used for determining the direction of primary flow lineation in volcanic rocks. Oriented samples were collected from the McCartys Basalt, the porphyritic andesite of Mount Taylor and the Bandelier and Battleship Rock Rhyolite Tuffs of the Jemez Mountains. All these localities are in New Mexico. Measurements were taken of the elongate particles in each horizontal thin section. The flow lineation direction in each slide was determined statistically by computing values of vector mean or chi-square orientation. The McCartys flow samples showed the lowest reliability. This was probably …
A Petrochemical Study Of Compositionally Zoned Ash-Flow Tuffs, David L. Giles
A Petrochemical Study Of Compositionally Zoned Ash-Flow Tuffs, David L. Giles
Earth and Planetary Sciences ETDs
Vertical compositional zoning occurs within the basal simple cooling units of two welded ash-flow tuff sheets, the Kneeling Nun and Caballo Blanco formations, in the Cobre Mountains of southwestern New Mexico. The sheets are on the southern edge of the Datil-Mogollon volcanic province. The Kneeling Nun (33.4 m.y.) varies abruptly but systematically upward from a modal quartz latite to latite, and the Caballo Blanco (29.8 m.y.) from a modal rhyolite to capping quartz latite. Both are crystal-rich, and in each the amount of ferromagnesian and plagioclase phenocrysts and phenocryst percent increases upward, while the quartz and alkali feldspar/plagioclase ratio decreases. …
Geology Of The Cerro Pelon-Arroyo De La Jara Area, Santa Fe County, New Mexico, Alvis Lee Lisenbee
Geology Of The Cerro Pelon-Arroyo De La Jara Area, Santa Fe County, New Mexico, Alvis Lee Lisenbee
Earth and Planetary Sciences ETDs
The Cerro Pelon-Arroyo de la Jara area is a north-northwesterly plunging syncline at the southern end of the Española basin. Exposed rock units consist of more than 5,000 feet of Mesozoic and Cenozoic shale and sandstone intruded by Oligocene diorite sills and andesite and latite dikes related to the Ortiz intrusive center to the west.
The syncline is affected by several fault systems with both normal and strike-slip movement represented. Northerly trending faults of the east limb combine with a monoclinal flexure to produce an over-all lowering of the section to the west. These faults appear to be related to …
A Stratigraphic Study Of The Navajo Sandstone, Navajo Mountain, Utah And Arizona, William O. Hatchell
A Stratigraphic Study Of The Navajo Sandstone, Navajo Mountain, Utah And Arizona, William O. Hatchell
Earth and Planetary Sciences ETDs
The Navajo Sandstone of the Triassic(?) and Jurassic age is approximately 1, 000 feet thick at Navajo Mountain, Utah, and is composed of sets of cliff-forming, highly cross-stratified sandstone and horizontally stratified limestone, siltstone, and sandstone. it is intertongued on a large scale with the underlying, fluvial Kayenta Formation of Triassic(?) age, and is comfortably overlain by the marine Carmel Formation of the Jurassic age.
In the highly cross-stratified Navajo, tabular-planner and wedge planner sets are more common than simple wedge sets, and persistent horizontal bedding and truncation planes distinguish individual sets. Ripple marks, a distinctive type of "graded bedding", …
Mineralogy Of Coesite And Petrographic Association And Distribution At Meteor Crater, Arizona., Alfred A. Burgoyne
Mineralogy Of Coesite And Petrographic Association And Distribution At Meteor Crater, Arizona., Alfred A. Burgoyne
Earth and Planetary Sciences ETDs
Natural coesite, the high density monoclinic polymorph of silica, is found in shocked and melted sandstone at Meteor Crater, Arizona. Structural, morphological, and optical data have been obtained from synthetic coesite crystals and aggregates. Natural coesite occurs as microcrystalline anhedral grains which are unsuitable for the above determinations. In this study the following new data have been obtained for natural and synthetic coesite.
(1) The calculated and observed d spacings and their intensities for both natural and synthetic coesite have been reinvestigated through a 28 range from 100 to 750 for CuKo
(2) Nearly all grains of synthetic …
Stratigraphy Of The Lower Morrison Formation Along The Defiance Monocline, New Mexico And Arizona, Robin Clair Lease
Stratigraphy Of The Lower Morrison Formation Along The Defiance Monocline, New Mexico And Arizona, Robin Clair Lease
Earth and Planetary Sciences ETDs
Along the western border of the San Juan Basin a prominent cliff-forming, orange sandstone has been incorrectly mapped as a part of the Recapture Shale Member of the Morrison Formation. This stratigraphic unit is here given the informal name, Beautiful Mountain member, and has stratigraphic continuity with the Salt Wash Sandstone Member in Red Rock Valley and the Cow Springs Sandstone in Todilto Park, New Mexico. The Recapture Shale Member is restricted to the pink and pale-green, slope-forming sandstone above these orange sandstone beds and below the Westwater Canyon Sandstone Member.
The Beautiful Mountain member is predominantly a lenticularly bedded, …