Physical Sciences and Mathematics Commons^™

Lower Jurassic Fluvio-Lacustrine Deposits Of The Glen Canyon Group, Sw Utah, Samuel A. Abdala

Loma Linda University Electronic Theses, Dissertations & Projects

Lower Jurassic fluvio-lacustrine deposits of the Kayenta Formation and Whitmore Point Member reveal past climatic and tectonic conditions in SW Utah. Fluvial overbank deposits and sparse channel belts characterize the Kayenta’s intermittent fluvial system. Reconstructed dune morphology matches that of modern rivers. Downstream bar accretion, as in braided channels, is indicated by numerical reconstruction. Vertical succession of cross-set thickness and grain size shows covariance drop up-section. This, along with a decreasing sand/mud ratio of sandstones suggests that suspended load increased up-section. The Kayenta vertically progresses from poorly-channelized sandsheets to wide channel-fills. Paleohydraulics-derived sandstone body widths are smaller than those measured …

Storm-Dominated Diatomite: Transport And Deposition From Micro-Texture, Taylor Kelln

Loma Linda University Electronic Theses, Dissertations & Projects

Unusually thick accumulations of diatomite and diatomaceous mud- and siltstones occur throughout the Mio-Pliocene along the Pacific margin. These extensive micro-fossil assemblages represent an important biostratigraphic resource, record of environmental conditions, and are economically relevant as unconventional reservoirs, sources and seals. Most depositional models for diatomaceous sediments tend to emphasize diatom productivity sufficient to overcome siliciclastic dilution and reflect a low-energy depositional regime with passive settling of diatoms through the water column. However, the diatomaceous sediments of the Pisco Basin, Peru, have been observed in longitudinally bedded, wavy, non-parallel laminated deposits, interpreted as hummocky-swaley cross-stratification. Other outcrop observations include tempestite-like …

Characterization Of Cross-Bed Depositional Processes In The Coconino Sandstone, Sarah A. Maithel

Loma Linda University Electronic Theses, Dissertations & Projects

The Permian Coconino Sandstone of northern and central Arizona is widely recognized as a classic eolian dune deposit, with conspicuous large-scale cross-beds that are interpreted as preserved dune foresets. On modern bedforms, fine-scale processes – which include grainflow, grainfall, and ripple migration – transport and deposit sediment, and these may provide useful analogs for interpreting ancient deposits. Even though the Coconino Sandstone is well known, such fine-scale process models have not been adequately developed to explain its cross-bed deposition. Furthermore, observed discrepancies between the sandstone and some eolian criteria suggest that additional study is needed to explore and refine these …

Behavioral Causes Of Paleopathologies In Cretaceous Edmontosaurus Annectens, Lance Formation, Wyoming, Bethania C. T. Siviero

Loma Linda University Electronic Theses, Dissertations & Projects

The study of dinosaur paleopathology has enriched our understanding of their living conditions and their intra- and interspecific behavior. In this study, I examined lesions on bones from a monospecific bone bed (Edmontosaurus annectens) and their implications for E. annectens behavior and the ecological conditions that affected this population. The bone bed contains abundant, mostly well-preserved, scattered, and disarticulated bones, mostly representing an adult population of E. annectens. From the 3013 bones examined, 96 bones displayed genuine pathologies such as: hypertrophic ossification, healed fractures, tooth traces, idiopathic or traumatic shaft angulation, bone fusion, degenerative joint diseases, osteochondrosis, infection, neoplasm, and …

Geomorphology Of The Potholes Of Rock Window Mesa, Chinle Valley, Az, Monte Fleming

Loma Linda University Electronic Theses, Dissertations & Projects

Potholes are depressions that have been carved out of bedrock. For this research project, we studied the 50 potholes on the top of Rock Window Mesa in Chinle Valley, AZ. Our first goal was to understand the processes currently affecting the addition or removal of pothole sediments. Our second goal was to understand pothole formation. While studying pothole sediment removal, we discovered that the wind speed threshold for deflation in the potholes is about 50 km/h, independent of pothole size. We conclude that deflation is the reason potholes don’t fill with sediment. In our study of pothole formation, we analyzed …

Conduction Plus Convection Heat Flow Modeling For The Linga Complex, Peruvian Coastal Batholith, Luciano Uriel González Olivares

Loma Linda University Electronic Theses, Dissertations & Projects

Factors affecting the thermal evolution of the Linga magmatic intrusion in the Ica-Pisco area of the Peruvian Coastal Batholith were studied using field work, petrography, geochemistry data, and computer modeling. Field work and petrography involved collecting samples for geochemical analysis and documenting widespread propylitic and potassic hydrothermal alteration. Major element geochemistry was used to estimate rock density, viscosity, liquidus temperature, and water content. The δ18O values of seven fresh samples showed a slightly increasing west-east and old-young trend of approximately 7-8‰, indicating an increasing crustal component. The δ18O and δD values for eleven altered samples indicated that alteration came mostly …

Unique Preservation Of Fossil Ghost Fish In The Green River Formation, Amanda L. Meacham

Loma Linda University Electronic Theses, Dissertations & Projects

Two beds with unique fossil fish preservation occur within the predominantly evaporite-rich, fossil poor Angelo Member in the Green River Formation in Fossil Basin, Wyoming. These two beds, termed “Ghost Fish” beds, contain fossil fish that are two-dimensional carbonaceous compressions with no bone and detailed soft part preservation. These beds were measured and samples were collected from 8 quarries and 19 additional locations. Stratigraphic sections and fossil content were recorded at each quarry location. Analysis included XRD, stable isotope, XRF, TOC, and SEM analysis. Results were inputted into tables, graphs, and spatial maps to show trends, interpret the paleoenvironment, and …

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

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

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

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

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 …

Taphonomy Of A Lance Formation(Maastrichtian, Wy) Dinosaur Bonebed With A Focus On Tooth Traces, Matthew A. Mclain

Loma Linda University Electronic Theses, Dissertations & Projects

The Rose Quarry bonebed found in the Maastrichtian Lance Formation of eastern Wyoming possesses a complex blendof taphonomic signatures. Disarticulated, disassociated, fragmented bones of various states of abrasion from dinosaurs, turtles, and crocodilians are clustered together in a channelized sandstone unit. The mismatched taphonomic signatures of the bonebed suggest that it is amixed assemblage, containing bones with different taphonomic histories that were washed together by a flood event. Sedimentological data,includingthe presence of large mud clasts in the bonebed,agree well with this hypothesis. The abundant breakage of the bones in the Rose Quarry bonebed is attributed mainly to trampling. This study …

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.

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 …

Soft-Sediment Deformation And Dune Collapse In The Navajo Sandstone, Colby Ford

Loma Linda University Electronic Theses, Dissertations & Projects

The Canyon Overlook Trail of Zion National Park follows an outcrop of Navajo Sandstone, which displays a uniquely well-exposed assemblage of features associated with failure of the lee face of a large eolian dune, and run-out over an expanse of interdune sediments downwind of that bedform. Exposed features include dramatic folds in the interdune succession and a stacked series of thrust sheets incorporating both interdune and overlying dune deposits. Thrust surfaces display consistent strikes, parallel to those of undeformed foresets, and incorporate zones of brittle failure and fluid deformation, including folds overturned in the direction of foreset dip. These features …

High-Resolution Correlation Of A Time-Bounded Unit Of The Pisco Formation, Peru, Daniel J. O'Hare

Loma Linda University Electronic Theses, Dissertations & Projects

Correlation of beds in the Pisco Basin across significant distances is problematic and has not yet been effectively achieved. I chose to examine an interval bounded by two time markers, an 40Ar/39Ar-dated white tuff at the base and an 40Ar/39Ar-dated tuff couplet at the top. This interval was chosen because of the continuity and excellent exposure of the tuff beds at six distinct locations in a linear transect 30 km long. Correlation of units was achieved through 40Ar/39Ar dating, lithology, sedimentary structures, and magnetic susceptibility. The vertical and lateral variability in lithology, fossil assemblages, structures, and sequences was examined in …

Sedimentology Of Marine Vertebrate Burial In The Miocene Pisco Fm., Peru, Monte A. Fleming

Loma Linda University Electronic Theses, Dissertations & Projects

The Miocene Pisco Basin of Peru is known for abundant, well-preserved marine vertebrate fossils (Esperante et al. 2000). Cetacean fossils are particularly abundant—so much so that we were able to locate 10 outcrops containing specimens in cross section, which allowed us to do detailed sedimentological studies of the beds surrounding the whales. We discovered that six of the 10 specimens were buried in channels; the details of the other four burials are too disparate to meaningfully group together in categories. Chapters 3, 4, and 5 describe and discuss the six specimens found in channels, while Appendix A contains descriptions and …

Correlation And Paleoenvironments Above West T9.3 Tuff, Pisco Formation, Peru, Caleb Stanton

Loma Linda University Electronic Theses, Dissertations & Projects

The Pisco Basin is a Cenozoic forearc basin in west central Peru. Though outcrops are well exposed, contain little diagenetic overprint, or complex structural deformation, only rudimentary correlations between outcrops are published and no attempts have been made to define time-bounded subunits. The goal of this study is to develop high resolution-stratigraphy and paleoenvironmental interpretations for a time-bounded unit in the lower part of the Miocene Pisco Formation. In this study, we correlated, mapped, and dated a tuff couplet and associated beds over 25 km2. We measured eight sections that include the tuffs and conducted detailed facies analysis. Sections were …

Benefits And Barriers To Hiv Testing In A Population Of Federal Detention Inmates, Nicole A. Knight

Loma Linda University Electronic Theses, Dissertations & Projects

Voluntary HIV testing in combination with early medical intervention has been shown to be effective in reducing the rate of new infections and improving the health and life expectancy of those living with HIV. There are however several high-risk populations in the US that remain largely unreached by HIV testing efforts, some of which could be reached while they spend time in prison or jail. Per current Bureau of Prisons (BOP) policy, HIV testing is routinely offered only to “high risk” pretrial and sentenced inmates. We conducted a cross-sectional study with 721 pretrial and sentenced inmates who entered a large …

Never Smokers -- Are They More Sensitive To The Respiratory Health Effects Of Ambient Air Pollution?, Zuhair Saleh Natto

Loma Linda University Electronic Theses, Dissertations & Projects

Background: Several studies show an association between ambient particulate matter (PM) and all-cause mortality. The Adventist Health and Smog 1 (AHSMOG-1) study (N=6,338) has previously found associations between ambient air pollution and incident chronic obstructive pulmonary disease (COPD) using the spatial interpolation method from the three nearest fixed monitoring stations to residence and workplace. However, few studies have assessed the risk of death among disease specific subgroups such as those with COPD.

Objectives: The aims of this study were 1) to assess the effect of chronic exposure to ambient air pollutants on risk of all-cause mortality among persons with COPD …

Perceived Attitudes And Staff Roles Of Community Based Outpatient Clinics In Disaster Management, Pauline Antoinette Hodge-Hilton

Loma Linda University Electronic Theses, Dissertations & Projects

Objective: Natural and manmade disasters have claimed the lives of thousands of individuals in the US and caused billions of dollars in property damage. First responders carry the responsibility of disaster management, leaving other health care professionals such as medical clinic staff underutilized to support the clinic staff. We explored how medical and support staff in Community-based Outpatient VHA Clinics (CBOC) perceive their roles in disaster response, their attitudes about clinic readiness and continuity of care during disasters, and their ability to function in a post disaster environment.

Methods: A mixed method study was conducted to answer questions related to …

Successful Aging And Creativity : An Investigation On Functional Status And Psychological Wellbeing In Older Adults, Mirie E. Levy

Loma Linda University Electronic Theses, Dissertations & Projects

Objectives: While the literature supports the maintenance of functional status as integral to successful aging, the relationship of creativity on functional status has received little attention. Creativity has been associated with health and aging in the research but only a small number of studies have examined creativity interventions to enhance functional status and boost psychological wellbeing.

Methods: A pretest-posttest quasi-experimental design was used to investigate an 8-week creativity intervention on functional status and psychological wellbeing in older adults. Sample subjects were 92 men and women all over age 60. A series of two-way mixed ANOVAs measured differences between treatment and …

Maternal Smoking, Weight Status And Preecalmpsia And Eclampsia Risk Among Women Living In San Bernardino County, Fiona Bedelia Lewis

Loma Linda University Electronic Theses, Dissertations & Projects

Preeclampsia is defined as pregnancy-induced hypertension affecting between 2% and 8% of pregnancies and accounting for about 10-15% of maternal deaths worldwide. Eclampsia is defined as the occurrence of one or more episodes of seizures in a pregnant woman related only to a preeclampsia diagnosis. Preeclampsia, if poorly managed, can progress to eclampsia resulting in injury and death to both mother and infant. The etiology of preeclampsia is not completely understood. Oxidative stress leading to abnormal placenta development and endothelial dysfunction are thought to be key components in the biological mechanism of preeclampsia.

Modifiable risk factors include maternal body weight …

The Association Of Diet And Physical Activity With Stroke Mortality Results From The Adventist Health Study-1, Tahereh Zamansani

Loma Linda University Electronic Theses, Dissertations & Projects

Stroke is one of the leading causes of death and disability, with major global public health implications. Stroke ranks No. 4 among all causes of death, behind heart disease, cancer, and chronic lower respiratory disease (CLRD). Stroke accounts for almost 1 of every 18 deaths in the United States. Women accounted for 60.6% of stroke deaths. Death certificate data show that the mean age at stroke death was 79.6 years; males had a younger mean age (76.3) than females.

There is still a great scientific uncertainty among researchers and epidemiologists about the magnitude of any preventive effect, mechanisms of action …

Evaluation Of The Survival Effect For Various Treatment Modalities Among Stage Ii And Iii Rectal Cancer Patients In California, 1994-2009, Myung Mi Cho

Loma Linda University Electronic Theses, Dissertations & Projects

Background: European trials evaluating the effect of preoperative (PreOP) versus postoperative chemoradiotherapy (PostOP CRT) found no survival benefit. However, the effect of a change from PostOP to PreOP CRT has not been evaluated in a population-based setting. We sought to evaluate multimodal treatment changes and overall survival for perioperative (PeriOP) CRT versus surgery alone and for PreOP versus PostOP CRT from 1994 through 2009 among patients receiving radical surgery for stage II and III rectal cancer (RC).

Patients and Methods: We conducted a nonconcurrent cohort study evaluating demographic predictors of multimodal therapy for stage II and III RC using …

The Morbidity & Mortality Of Prevalent Heart Failure, Jennifer Kwon

Loma Linda University Electronic Theses, Dissertations & Projects

The first study population included 292 unselected consecutive patients from the LLUMC heart failure clinic who were enrolled in the study from January to July 2006 and were followed up through the end of December 2010. The treatment policy at the clinic was to uptitrate dosages of beta-adrenergic blockade (β-blockers), angiotensin-converting-enzyme inhibitors (ACEi) and angiotensin II receptor blockers (ARB) to the most tolerable levels in order to reach target dosages, as recommended by the Heart Failure Society of America (HFSA). Patients were classified into systolic heart failure (ejection fraction (EF) < 40%) or diastolic heart failure (EF≥40%). All dosages of β-blockers, ACEi and ARB were extracted through chart reviews and were used as the main predictors of the patients' survival. Results from analyses showed that reaching target dosages of β-blockers and ACEi/ARB may increase survival when compared to not reaching target among the systolic HF population (HR_{β_biockers}= 0.64, 95% CI 0.26-1.56 and HR_ACEi/ARB=0.50, …

Paragenesis Of Lacustrine Microbialites In The Upper Wilkins Peak Member, Green River Formation, Wyoming, Bethania Chagas Tosta Siviero

Loma Linda University Electronic Theses, Dissertations & Projects

Microbialites from the upper Wilkins Peak Member were investigated to determine their paragenesis and to help interpret lake chemistry. Two specific microbialite beds were analyzed that are associated with the “layered tuff”. Samples were collected from correlated sections along a NW to SE, 24 km line of section from lake margin towards lake center. XRD, SEM/EDS, and petrographic analysis show differences in diagenesis above and below the layered tuff.

Microbialites below the tuff bed contain some primary calcite with diagenetic dolomite and abundant secondary silicification. Later, dolomite replaces both calcite and quartz. Pores are commonly filled with 20 μm euhedral …

The Efficacy Of An Audio Program And Discussion Guide In Promoting Exclusive Breastfeeding In Cameroon, Africa, Kathryn R. Reinsma

Loma Linda University Electronic Theses, Dissertations & Projects

Background: In the Northwest Region of Cameroon, approximately 90% of women initiate breastfeeding; however, only 34% continue exclusive breastfeeding for the recommended six months (Kakute, et al., 2005; WHO, 2008). Entertainment-education is a mass-media communication strategy of placing educational information into media such as television programs, movies, and radio programs (Siegel & Lotenberg, 2007). This form of behavioral change communication has proven effective in addressing health-related issues in developing countries.

Purpose: The aim was to design an audio program and discussion guide to test the hypothesis that an audio program and discussion guide improves exclusive breastfeeding knowledge, beliefs, benefits, self-efficacy, …

Age, Stratigraphy And Depositional Environment Of The Pliocene Copper Canyon Formation, Death Valley, California, Torrey Nyborg

Loma Linda University Electronic Theses, Dissertations & Projects

The Copper Canyon Formation, a fluvial-lacustrine deposit exposed within the Black Mountains of Death Valley National Park, has only previously been broadly included in regional tectonic and depositional analyses. The formation is significant because it preserves numerous shoreline-playa features including highly abundant and diverse mammal and bird tracks. The formation represents a basin fill sequence consisting of approximately 1800 m of conglomerates, basalt flows, and lacustrine deposits. A measured type section along with x-ray diffraction, isotopic analysis, and thin section petrography shows an evolution of the ancient Copper Canyon lake from an hypersaline evaporative lake to a perennial saline lake …