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Application Of Geophysics And Remote Sensing Techniques For Economic Mineral Exploitation In Libya, Awad Abdussalam Henish Lemnifi

Doctoral Dissertations

“This study investigates crustal thickness and properties within the north central Africa region. Results obtained from 15 seismic stations belonging to the Libyan Center for Remote Sensing and Space Science are reported, in addition to 3 seismic stations publically available, using receiver functions, the first P-to-S receiver function investigation of the 410 km and 660 km depth discontinuities bounding the mantle transition zone (MTZ), and P wave tomography methods. The results from the first method show crustal thicknesses ranging from 24 km to 36 km (with uncertainties ranging between ±0.10 km and ±0.90 km). More specifically, crustal thickness ranges from …

Estimation Of Measurement Uncertainty Of Seafloor Acoustic Backscatter, Mashkoor Malik

Doctoral Dissertations

In the last three decades, Multibeam echo sounders (MBES) have become the tool of choice to study the seafloor. MBES collects two distinct types of data: bathymetry that provides topographic details of the seafloor and backscatter that has the potential to characterize the seafloor. While the uncertainty associated with MBE bathymetry has been well studied, the uncertainty in MBES backscatter measurement has received relatively little attention, hindering the improvements in quantitative analysis of backscatter data. Both acquisition and processing stages can introduce uncertainty in the final seafloor backscatter products. Application of well-established uncertainty quantification principles to seafloor backscatter data is …

Military Applications Of Geological Engineering, Stephen H. Tupper

Doctoral Dissertations

"This work examines the premise that military engineering and geological engineering are intellectually paired and overlapped in practice to a significant extent. Geological engineering is an established, albeit young, academic discipline that enjoys wide industry and civil demand and is supported by many professional organizations. In contrast, military engineering is an ancient, empirically derived training or "OJT" program with practice-based trade-associations that has narrow government-only utility. The premise is formed by decades-long observation of U. S. Army military engineer officers completing a Master of Science degree in geological engineering as a complement to their practice-based training in military engineering at …

Geomorphology Of The Connecticut River, Glastonbury Reach, As A Spatial-Temporal Context For Understanding Pre-Contact Settlement Patterns, Jaime Grant

Doctoral Dissertations

The primary objective of this research was to identify the alluvial geomorphic filters that obscure remnant settlement patterns and in so doing refine our understanding of Pre-contact settlement systems during the Archaic Period and Woodland Periods, a time of environmental change followed by settlement and subsistence shifts.

Statistical analysis of Connecticut’s site distribution, historic planform analysis and partial reconstruction of the Glastonbury Reach during the Woodland Period revealed patterns in the Late Archaic through Woodland Periods (5000–300B.P.) floodplain site distributions. This research demonstrates that the development of a meandering alluvial reach coincided with a shift in settlement that began in …

Imaging Beneath Standing Bodies Of Water In Karst Terrain, Abdulrahman Masfer Alotaibi

Doctoral Dissertations

"Side scan sonar and down scan sonar, sub bottom profiling, electrical resistivity tomography profiling (underwater cables), and continuous resistivity profiling (towed cable) surveys were conducted to characterize the lake sediments (rock and soil) beneath the man-made Little Prairie Lake, in central Missouri. Sub bottom profiling and electrical resistivity (with marine cables and towed cable) were used to determine variability in the lithology and thickness of sediments (soil and rock) beneath the lake, while side scan sonar was used to map the variations in the lithology/nature of exposed lakebed sediments and to locate the potential hazard of trees. Down scan sonar …

Apparent Weekly And Daily Earthquake Periodicities In The Western United States, And Evolution Of Wadi Kubbania In Egypt, Ali Hadi Atef

Doctoral Dissertations

"The dissertation consists of two separate sections. The first section is on apparent daily and weekly periodicities in earthquake occurrence in the western United State [sic]. Analysis of Apparent Seismicity Rate (ASR) in the western United States confirmed the existence of prominent spectral peaks with a period of 1 and 7 days. The number of recorded earthquakes on Sundays for the duration of 1963-2008 is about 5% higher than that on weekdays, and, more significantly, there is a 9% increase of ASR in the early morning compared with that in the middle of the days. Significant similarities between the spatial …

Determination Of Geotechnical Properties Of Seafloor Sediment Using A Free Fall Penetrometer, Gopala Krishna Mulukutla

Doctoral Dissertations

A study was conducted to determine the penetration behavior of a cylindrical probe free falling to the seafloor and to utilize the data obtained to evaluate the engineering properties of surficial sediment. Two experimental probes, each equipped with accelerometers, pressure sensors and optical backscatter sensors were deployed in different sediment regimes. The data collected was used to derive the sediment type and determine physical properties such as undrained shear strength, coefficient of consolidation and shear modulus for soft fine-grained sediment.

Acceleration signals from drops of a free fall penetrometer contain information about the nature of the seafloor. A simple sediment …

An Investigation Of Lead And Other Metal Contaminants In The Sediments Of Clearwater Lake, Missouri, Gary W. Krizanich

Doctoral Dissertations

"The purpose of this investigation is to characterize the spatial and temporal distribution and concentration of trace metals in sediments of Clearwater Lake. Understanding how trace metals are released to and transported in aquatic environments is important to the overall understanding of the impacts of mining on the natural environment. The main focus of this research will be on historic sedimentation within Clearwater Lake, which may act as a sink where mining related trace metals are stored. Because of their high preservation rates in basins, sediments can provide detailed chronostratigraphic histories of trace metal inputs in lakes. Sediment records can …

Genetic Basis Of Adaptive Radiation In East African Cichlids, Richard Craig Albertson

Doctoral Dissertations

East African cichlids are a paramount example of adaptive morphological radiation. The most dramatic difference among species occurs in oral jaw design and correlates with ecological niche partitioning. Convergent evolution of trophic forms between lakes suggests a common mechanism. What combination of intrinsic and extrinsic factors constitute this mechanism still remains to be seen. The goal of this dissertation was to examine the genetic basis of shape differences between two closely related cichlid species that employ alternate modes of feeding. This was achieved through a number of independent experiments. First, I used field data to characterize the way in which …

Geochronology And Geochemistry Of The Basement Orthogneisses Of The Araguaia Belt, Brazil, Candido A Veloso Moura

Doctoral Dissertations

Orthogneisses representing the basement rocks of the Araguaia belt (AB), Brazil, are exposed in the core of dome-like structures. Gneisses of trondhjemitic, tonalitic, and granodioritic (TTG) composition constitute the Colmeia Complex, while augen gneiss, of granitic composition, is termed Cantao Gneiss (CG). An Archean age is suggested for the TTG gneisses, although the available Rb-Sr ages for these rocks range between 1.8 and 2.6 Ga. A Rb-Sr age of 1.77 Ga for the CG is interpreted either as a crystallization age or a resetting age.

Geochronological and geochemical studies of the orthogneisses of five of these dome-like structures of the …

Metal Resistance In Alcaligenes Marinus By Production Of Extracellular Binding Agents, James Beaven Rake

Doctoral Dissertations

No abstract provided.

Geology Of The Al-Khums Area Northwestern Libya With Emphasis On The Stratigraphy And Biostratigraphy Of The Al-Khums Formation, Mostafa Juma Salem

Doctoral Dissertations

"The dissertation represents a geologic study of an area bordering the Mediterranean Sea in northwestern Libya. About 1200 km² were mapped and 28 stratigraphic sections were prepared.

The bedrock consists of 16 stratigraphic units of Mesozoic and Cenozoic age having a combined maximum thickness of about 750 meters. The oldest unit exposed, the Abu Shaybah Formation, is a redbed sequence of Triassic and Jurassic age. These beds are unconformably separated from Cretaceous carbonates (Garian Limestone, Ain Tobi Formation, and Gezzar Dolomite). These units in turn are overlain by the Miocene Al-Khums Formation. Younger Quaternary units consist of nearshore marine …

Classification Of Surficial Materials, James Hadley Williams

Doctoral Dissertations

"A surficial materials classification system has been designed to fit the needs of a geologist in mapping and classifying surficial materials. The system developed in this study is intended primarily for analysis of surficial materials where time-stratigraphic markers are not applicable or recognized. Primary classification is based on fabric and mode of origin supplemented by data on engineering and pedologic properties.

Several types of classification systems presently exist for use in soil investigations. Only three of these systems have found widespread acceptance, two serving the engineering profession and the other the needs of the soil scientist. These systems are not …

Stratigraphy, Genesis, And Economic Potential Of The Southern Part Of The Florida Land-Pebble Phosphate Field, Dean Stanley Clark

Doctoral Dissertations

"The important and highly productive Florida land-pebble phosphate field is located in west central peninsular Florida in portions of Hillsborough, Polk, Hardee, and Manatee counties. The Pine Level phosphate area, described in detail in this report, is south of the previously known and mined deposits and occurs in portions of Manatee, Sarasota, and De Soto counties. Results of the current geologic study of the Pine Level phosphate deposit and the evaluation of the overall potential of this southern part of the land-pebble field are presented.

The entire southern part of the phosphate field is underlain by more than 15,000 feet …

The Mio-Eugeosynclinal Thrust Interface And Related Petroleum Implications In The Sason-Baykan Area, Southeast Turkey, Ismail Özkaya

Doctoral Dissertations

"A detailed investigation of the stratigraphy, structure and petroleum geology of the Sason-Baykan region in 600 square km area of the thrust belt of southeast Turkey was completed at a scale 1: 25 000. Geosynclinal sediments within the area were redated.

Results of field study indicate a massive plate of metamorphic rocks and crystalline limestones was thrust southward over geosynclinals sediments. These in turn were thrust over the southern marginal basin deposits. A stratigraphic sequence of the allochthonous geosynclinals sediments was reconstructed and correlated with the autochthonous Tertiary section. Contrary to earlier views the allochthonous sediments and accompanying igneous rocks …

Mineral Paragenesis And Trace Element Distribution In The Tri-State Zinc-Lead District Missouri, Kansas, Oklahoma, Richard D. Hagni

Doctoral Dissertations

"A review of the literature pertaining to the mineral paragenesis and trace element distribution in the Tri-State zinc-lead district of Missouri, Kansas, and Oklahoma revealed inconsistencies in observation and in interpretation and divergent hypotheses regarding the origin of the ores. In an attempt to reconcile the data collected by many investigators over nearly three-quarters of a century, the writer observed working faces in 37 mines, collected over 2,000 specimens for binocular examination and prepared and studied 110 polished surfaces and 60 thin sections of the ores and associated rocks utilizing mineralographic, petrographic, and x-ray techniques. This detailed study resulted in …