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Full-Text Articles in Stratigraphy

Diversity – Independent Factors Predict Elevated Extinction Rates, Dustin Perriguey, Corinne Myers, Jason Moore, Louis Scuderi Apr 2021

Diversity – Independent Factors Predict Elevated Extinction Rates, Dustin Perriguey, Corinne Myers, Jason Moore, Louis Scuderi

Earth and Planetary Sciences ETDs

Multiple linear regression was used to determine the relationships between diversity-independent factors (i.e., abiotic, climatic) 2, 5, and 10 Myrs-prior to the most elevated Phanerozoic extinctions. We constructed five abiotic variables from Phanerozoic proxy records1–5 to compare to extinction rates: mean temperature, temperature instability, carbon cycle instability, continental weathering rates, and habitat instability. All three models were statistically significant (P < 0.05) and explained > 70% of the variation in Alroy’s6 three-timer generic extinction rates. However, the 2 Myr-prior model explained the most variance in extinction rates and had the most predictive power, based on adjusted and predictive R2 (~ 72% and 41%, respectively). Carbon …


Integrated Studies Of Intracontinental Deformation In The Interior Western Usa, Cretaceous To Recent, Jacob Oliver Thacker May 2020

Integrated Studies Of Intracontinental Deformation In The Interior Western Usa, Cretaceous To Recent, Jacob Oliver Thacker

Earth and Planetary Sciences ETDs

The advent of plate tectonic theory satisfactorily explained a number of deformation belts around the world. However intracontinental deformation (deformation inboard of a plate margin) remains poorly understood in plate tectonic models. In order to further our understanding of intracontinental tectonics and its effects, this dissertation examines paleotectonic and neotectonic settings within the interior western USA.

Chapter 1 focuses on late Miocene–Recent deformation inboard of the San Andreas plate margin fault and its role on the integration history of the lower Colorado River. The neotectonic analysis included geometric and kinematic fault data collected in key geologic units to characterize the …


Sedimentology And Stratigraphy Of Core Stl14: An Early Pleistocene-To-Present Paleoclimate Archive From Stoneman Lake, Arizona, Spencer Staley Nov 2018

Sedimentology And Stratigraphy Of Core Stl14: An Early Pleistocene-To-Present Paleoclimate Archive From Stoneman Lake, Arizona, Spencer Staley

Earth and Planetary Sciences ETDs

An 80 m lacustrine sediment core (STL14) from Stoneman Lake, Coconino County, Arizona, contains a sedimentary sequence of at least 1.5 million years, chronicling the complete history of basin infill and recording an extensive and high-resolution archive of climatic and hydrologic fluctuations. Lake levels in this small, internally-drained catchment are sensitive to changes in regional hydrologic balance. Consistent groundwater inflow, even during regionally dry episodes in the lake’s history, has prevented complete desiccation of the lake and sustained continuous lacustrine deposition except for one soil horizon. Multiproxy analysis of sedimentological indicators including lithofacies, color, wet bulk density, magnetic susceptibility, preliminary …


Stratigraphic Analysis Of The Queen And Grayburg Formations, Southeastern Chaves County, New Mexico, James L. Mcswain May 1963

Stratigraphic Analysis Of The Queen And Grayburg Formations, Southeastern Chaves County, New Mexico, James L. Mcswain

Earth and Planetary Sciences ETDs

The area of study lies in southeastern Chaves County, New Mexico, and is a part of the northwest shelf or backreef province of the Permian Basin. The area encompasses all or parts of Tps. 10 through 15 S., Rs. 24 through 31 E.

The Queen and Grayburg formations comprise the lower part of the Artesia group, an upper Guadalupian sequence of Permian shelf rocks above the San Andres formation and below the Ochoan series. The Queen-Grayburg sequence has an average thickness of about 600 feet and is correlative with the Goat Seep reef at the margin of the Delaware Basin, …


Geology Of The Northern Part Of The Fra Cristobal Range, Sierra And Socorro Counties, New Mexico, John T. Mccleary May 1960

Geology Of The Northern Part Of The Fra Cristobal Range, Sierra And Socorro Counties, New Mexico, John T. Mccleary

Earth and Planetary Sciences ETDs

The northern part of the Fra Cristobal Range contains rocks of Precambrian, Cambrian, Pennsylvanian, Permian, Cretaceous, Tertiary and Quaternary age. One of the northernmost exposures in New Mexico of the Cambrian Bliss formation occurs in the central part of the range. Here the bliss formation wedges out due to widespread pre-Pennsylvanian erosion which removed all the other lower Paleozoic rocks.

The Pennsylvanian Magdalena group, which is predominately limestone, rests uncomformably on Precambrian rock and the Bliss Formation. It forms the greatest part of the sedimentary sequence and is divided into three formations; the Red House, Nakaye, and Bar B formations …


Geology Of The Southern Part Of The Ortiz Mountains Santa Fe County, New Mexico, John W. Peterson May 1958

Geology Of The Southern Part Of The Ortiz Mountains Santa Fe County, New Mexico, John W. Peterson

Earth and Planetary Sciences ETDs

The Ortiz Mountains lie in a belt of early Tertiary intrusive centers adjacent to the Rio Grande depression of north-central New Mexico. Tertiary organic activity and subsequent erosion have etched this mountain group into considerable relief.

Intrusive activity occurred during early Tertiary Espinaso time and resulted in emplacement of sills and dikes of a central stock. Correlation of volcanism with intrusive phases is difficult. Most volcansim probably occurred during the later part of Ortiz igneous activity. An elongate vent is exposed in the eastern part of the mountains and structurally occupies the highest position in the group.

The principle igneous …


Geology Of The Northern Part Of The Ortiz Mountains, Santa Fe County, New Mexico, Otis M. Mcrae Apr 1958

Geology Of The Northern Part Of The Ortiz Mountains, Santa Fe County, New Mexico, Otis M. Mcrae

Earth and Planetary Sciences ETDs

The northern part of the Ortiz Mountains of north-central New Mexico consists of a tilted fault block of Cretaceous Mancos shale and Mesaverde formation intruded by latite-andesite porphyry sills and laccoliths and a nepheline-bearing augite manzonite stock. Igneous activity started with the development of a volcanic vent in what is now the central part of the mountains. Volcanic debris from the vent want removed from the area by erosion and provided sedimentary material for the late [ ] Espinaso volcanics of the adjoining areas. Intrusion of the latite-andesite porphyry sills and laccolite followed extrusive igneous activity, as demonstrated by the …


Paleontology And Stratigraphy Of The Jemez Springs Area, Sandoval County, New Mexico, Bill P. Lovejoy Jan 1958

Paleontology And Stratigraphy Of The Jemez Springs Area, Sandoval County, New Mexico, Bill P. Lovejoy

Earth and Planetary Sciences ETDs

The Jemez Springs area of north-central New Mexico contains rocks ranging in age from Precambrian to Recent. Resting on Precambrian granite are 15 to 20 feet of Mississippian limestone and shale belonging to the Arroyo Peñasco formation of probable Meramecian age. The marine fauna is restricted to Pennsylvanian rocks. In this study. 64 species representing 40 genera were recognized, and the majority are illustrated and systematically described. Fossil evidence indicates a Lampasan (Atokan) age for the Sandia formation and a Desmoinesian, Missourian, and Virgilian age for the Madera limestone. Correlation was based primarily on the predominant and well-preserved brachiopod fauna. …


Geology Of The Canjilon Cauldron Sink Near Bernalillo, Sandoval County, New Mexico, Felix E. Mutschler May 1956

Geology Of The Canjilon Cauldron Sink Near Bernalillo, Sandoval County, New Mexico, Felix E. Mutschler

Earth and Planetary Sciences ETDs

Canjilon Hill is located on the west side of the Rio Grande, about 2 3/4 miles north-northwest of Bernalillo. Exposed on the hill is a local unit of breccia, conglomerate, and sandstone, which forms an elongate saucer-shaped body 4100 feet long, 2200 feet wide and 280 to 500+ feet thick. Unlike the underlying Santa Fe formation these strata contain an abundance of large angular basalt pebbles, cobbles, and boulders. In this paper these strata are termed the Canjilon formation of the Santa Fe group. Structural and sedimentological evidence suggest that the Canjilon formation was deposited in a subsidence depression initiated …


Geology Of The Southern Ladron Mountains, Socorro County, New Mexico, E.A. Noble Apr 1950

Geology Of The Southern Ladron Mountains, Socorro County, New Mexico, E.A. Noble

Earth and Planetary Sciences ETDs

The Ladron Mountains are in a fault-block range consisting in large part of Pre-Cambrian rocks. They are flanked on the west by Paleozoic sediments and elsewhere by Tertiary and Quaternary deposits. The Pre-Cambrian rocks of the southern Ladron Mountains consist of a thick sequence of quartzite and schist which has been granitized by a sub-adjacent intrusion to such a degree that only remnants of unaltered quartzite and schist remain, the remainder of the rocks being largely paragneiss and para-granite. The nature of the intrusion is not known, but it is suggested that it may have been at least partly formed …