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- Keyword
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- Granitic Plutons; Crustal Recycling; Magma Mixing; Mantal and Crustal Magma; Crystallization; Elemental and Isotope Geochemistry (1)
- Igneous rocks -- analysis; Mesozoic Cordilleran Arc; Peninsular Ranges batholith; Geochemical data; Magmatic processes; Plate Tectonics (1)
- Lance Formation (Maastrichtian) -- Wyoming; Facies analysis; Bonebeds; Depositional plain; (1)
- Neoproterozoic formations; Kingston Peak Formation; Beck Spring Dolomite; Sedimentary Structures (1)
- Paleo-environments; Hurricane Mesa (1)
Articles 1 - 7 of 7
Full-Text Articles in Physical Sciences and Mathematics
Cyclically-Forced Hyperpycnites Of The Ancient Colorado River Proximal Prodelta, Sandra R. Waresak
Cyclically-Forced Hyperpycnites Of The Ancient Colorado River Proximal Prodelta, Sandra R. Waresak
Loma Linda University Electronic Theses, Dissertations & Projects
Prodeltaic deposits record a distal, minimally reworked archive of dominant processes active at the fluvial-marine interface. The Fish Creek-Vallecito Basin (CA, US) preserves an ~3 km-thick, lower Pliocene, progradational deltaic succession formed when the ancestral Colorado River infiltrated the early Gulf of California. The interpreted prodeltaic unit in this succession (Mud Hills Member of the Deguynos Formation) contains an ~40 m-thick interval of rhythmic bedding with consistently alternating silt- to fine sand-dominated and clay-dominated beds forming couplets with an average thickness of 12 cm. Sedimentological analysis of the rhythmites reveals the couplets are laterally persistent with gradational to sharp, flat …
Compositional Diversity In Arcs: A Record Of Magmatic Processes In The Peru Coastal Batholith, Ica, Ana Maria Martinez Ardila
Compositional Diversity In Arcs: A Record Of Magmatic Processes In The Peru Coastal Batholith, Ica, Ana Maria Martinez Ardila
Loma Linda University Electronic Theses, Dissertations & Projects
Peruvian granitic plutons display evidence for crustal recycling and magma mixing. Evidence of physical and chemical processes operating during the formation of the Ica-Pisco complexes involves magma mixing and mingling as result of felsic and mafic interactions. Evidence of crustal recycling was identified from kilometer-scale cauldron subsidence, meter and centimeter-scale -stoping, and disaggregation. At the petrographic microscope scale, evidence for recycling and mixing between mantle and crustal magma during crystallization is found from disequilibrium features such as reaction rims, resorbed cores, and patchy zoning. Elemental and isotope geochemistry data indicate that mantle magmas have incorporated continental crust material from varying …
Interpreting Southern California Arc Geochemistry By Multivariate And Spatial Methods, Lance R. Pompe
Interpreting Southern California Arc Geochemistry By Multivariate And Spatial Methods, Lance R. Pompe
Loma Linda University Electronic Theses, Dissertations & Projects
Exploratory data analysis methods of multivariate statistical techniques and spatial visualization are emerging trends in understanding big datasets. In this project, these techniques are applied to a large igneous geochemical dataset from the southern California segment of the Mesozoic Cordilleran arc to better understand magmatic and plate tectonic processes at a subduction zone. A set of 287 granitic samples collected by Baird and Miesch (1984) from the Peninsular Ranges batholith is analyzed for 38 geochemical elements. Patterns in both the geochemical variation and the spatial variation of this dataset are explored. Since geochemical data are compositional in nature, special treatment …
Depositional Model Of A Late Cretaceous Dinosaur Fossil Concentration, Lance Formation, Summer Rose Weeks
Depositional Model Of A Late Cretaceous Dinosaur Fossil Concentration, Lance Formation, Summer Rose Weeks
Loma Linda University Electronic Theses, Dissertations & Projects
A large Maastrichtian, nearly monospecific bonebed in the Lance Formation in eastern Wyoming has yielded 13,000 bones and fragments since 1996. Though excavation of the site continues, little is known of the circumstances and processes of deposition. This study aims to provide a depositional model for the bonebed. To accomplish this task we utilized 1D facies analysis of surrounding units and 3D analysis of the bonebed. The nature of the outcrop limited facies analysis to 1D. Four measured stratigraphic sections, each containing the bonebed unit, were taken and used in facies analysis. In addition, laterally continuous units were observed and …
The Growth And Ecology Of Upper Cambrian Microbialite Biostromes From The Notch Peak Formation In Utah, Ken P. Coulson
The Growth And Ecology Of Upper Cambrian Microbialite Biostromes From The Notch Peak Formation In Utah, Ken P. Coulson
Loma Linda University Electronic Theses, Dissertations & Projects
Exposure of carbonate rocks within the uplifted mountains of southwestern Utah presents a unique opportunity to study the growth, morphology and ecology of two upper Cambrian microbialite reefs located within the Hellnmaria Member of the Notch Peak Formation. The first reef contains meter-length, strongly elongate microbialites that grew in a deep, subtidal marine environment. These elongate microbialites formed as a result of coalescence of round ‘algal’ heads, a process known to produce compound microbialite structures in shallow water, but seldom explored as a key factor in the elongation of deep, subtidal forms that grew in ancient environments. The second reef …
Sedimentology Of Kingston Peak Formation Kp1 Beds In Beck Canyon Region, Kingston Range, California, Dominic Joel Ombati
Sedimentology Of Kingston Peak Formation Kp1 Beds In Beck Canyon Region, Kingston Range, California, Dominic Joel Ombati
Loma Linda University Electronic Theses, Dissertations & Projects
The Neoproterozoic Kingston Peak Formation (KPF) is known for its diamictites interpreted as of glacial origin. The KPF overlies the Beck Spring Dolomite (BSD) that contains microfossils and microbialites. This study aims to test correlation between outcrops and understand the abrupt change from BSD to KPF. It focuses on the basal 4 meters of the KP1 subunit of the KPF as it appears in the Beck Canyon region, Kingston Range, California. We describe and correlate sedimentary rocks at and immediately overlying the contact and analyze the sedimentary structures, textures and sequences. We have found only three sites in the northern …
Taphonomy Of Sediments: Bioturbation In The Triassic Moenkopi Formation In Southwestern Utah, James Vernon Bird Jr.
Taphonomy Of Sediments: Bioturbation In The Triassic Moenkopi Formation In Southwestern Utah, James Vernon Bird Jr.
Loma Linda University Electronic Theses, Dissertations & Projects
Measurement of bioturbation reflects physical and biological processes operating over time and can be used to reveal information about paleo-environments. The purpose of this study was to determine the intensity of bioturbation in Triassic Moenkopi Formation at Hurricane Mesa in Southwestern Utah. This formation is interpreted as having been deposited mostly in large ancient river channels, tidal flats, delta and shallow marine environments. Five stratigraphic sections measured in the Virgin Limestone Member provided the basis for this study. Detailed descriptions and quantification of bioturbation were recorded in each of the sections. Similar treatment was given to additional study sites in …