Department of Geological Sciences
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Item Tertiary Phosphates in Alabama(American Association for the Advancement of Science., 1885-05-08) Smith, Eugene A.Item Underthrust Folds and Faults(American Journal of Science, 1893) Smith, Eugene A.Item On Some Post-Eocene and Other Formations of the Gulf Region of the United States(The American Association for the Advancement of Science, 1906-03-30) Smith, Eugene A.Item Depositional Environment of the Tombigbee Sand Member - Mooreville Formation Contact at Selected Outcrops in Alabama(University of Alabama Libraries, 1968) Britton, Thomas A. Jr.; University of Alabama TuscaloosaA study was made of eighteen samples collected at four selected exposures of the contact of the Eutaw and Selma groups (Tombigbee Sand Member and Mooreville Formation) of Late Cretaceous (Austinian) age in central and west-central Alabama. The sediments consisted primarily of quartz sand and glauconite with muscovite and garnet secondary in abundance in the clastic fraction. Several of the samples were calcareous. Particle size analysis, fossils, and mineral content indicate the depositional environment before and after the erosional cycle between Tombigbee and Mooreville sedimentation was neritic and more likely epineritic. Certain areas of deposition may have existed as quite bays and lagoons as part of the shoreline as evidenced by the presence of glauconite and pyrite.Item Biostratigraphy of the Bluffport Marl Member of the Demopolis Chalk, Cretaceous of Alabama(University of Alabama Libraries, 1969) Newman, Harry Ellsworth, III.; University of Alabama TuscaloosaThe Bluffport Marl Member of the Demopolis Chalk was sampled to find what lithologic and paleontologic variations occur along the strike of this unit. The Bluffport Marl Member has been traced in Alabama from Sumter County eastward into the western edge of Lowndes County, somewhat farther east than reported in earlier publications. Insolubles increase upward in the section and along strike towards the eastern extent of the Bluffport Member, implying an eastern source of clastics. The abundant invertebrate faunal assemblage of the Bluffport decreases upward in the section and to the east in direct relation to the increase in clastics. Although the Bluffport species vary in abundance at different localities, the total number of species found is nearly consistent from location to location in the lower part of the section. Morphologically, there is very little difference in the western and eastern Bluffport fauna, although there is a significant decrease in size of these assemblages toward the upper part of the section. Based on faunal changes, this increase in clastics reflects environmental conditions that were below those optimum conditions that existed in the lower and more western Bluffport section and in which these reef assemblages thrived.Item Possible Origins of the Livingston Fault Zone(University of Alabama Libraries, 1972) Schneeflock, Robert Donald Jr.; University of Alabama TuscaloosaThe Livingston fault zone is restricted to the outcrop of the Selma Chalk of upper Cretaceous age in Sumter and Marengo Counties, Alabama. This zone is unique among Gulf Coastal Plain structures in that it contains many horsts and grabens which are bounded by reverse faults. These faults dip both to the northeast and southwest and strike North 70 degrees West with a mode for fault plane dip of 40 degrees to 45 degrees.Item Criteria for Distinguishing Pleistocene(?) Alluvial Terrace Deposits from the Coker Formation in the Cottondale, Alabama, Area(University of Alabama Libraries, 1975) Wielchowsky, Charles Carl; University of Alabama TuscaloosaField, textural, mineralogical, and geochemical data were collected from the Coker Formation of Cretaceous age and the alluvial terrace deposits of Pleistocene(?) age in the Cottondale area to determine those criteria that could be used in the differentiation of these two units. It was found that no single criterion could be used with complete confidence, though a series of general criteria were developed.Item Environments of Deposition of the Norphlet Formation (Jurassic) in South Alabama(University of Alabama Libraries, 1981) Wilkerson, Richard P.; University of Alabama TuscaloosaIn the western Gulf Coastal Plain area the Jurassic Norphlet Formation is typically characterized by non-marine and red bed lithofacies. In south Alabama the Norphlet consists of an updip conglomerate, a discontinous basal shale, red beds overlying the shale, and an upper quartzose sandstone, the Denkman Member. The Norphlet uncomformably overlies either salt, anhydrite, red beds, or Paleozoic rocks. The Smackover Formation, which overlies the Norphlet, has a sharp contact with the Norphlet over most of the study area except in parts of Mobile County.Item Stratigraphy and Depositional Environments of Part of the Pennsylvanian Pottsville Formation in the Black Warrior Basin: Alabama and Mississippi(University of Alabama Libraries, 1984) Sestak, Helen Maria; University of Alabama TuscaloosaDetermination of depositional environments is based on the interpretation of geophysical log signatures and the distribution of sandstones and coals. Most of these data have been obtained from dual induction and density logs of wells drilled to underlying Mississippian reservoirs. The Pottsville sediments have not been a major petroleum objective; however, the numerous coal beds are a potential source of methane.Item Depositional Systems in the Lower Part of the Pottsville Formation, Black Warrior Basin, Alabama(University of Alabama Libraries, 1985) Engman, Mary Anne; University of Alabama TuscaloosaThree depositional systems have been defined and named within the lower Pottsville Formation in the subsurface in Alabama: (1) the Fayette-Walker barrier system, (2) the Lamar marsh-lagoon system, and (3) the Pickens-Tuscaloosa delta system. These three distinctly different depositional systems were defined on the basis of data from electric logs, sandstone isolith maps, coal distribution, and core descriptions. The Fayett-Walker barrier system is composed of a thick section of northwest-southeast trending orthoquartzitic sandstones containing thin interbeds of mudstone and rare coal beds, and extends throughout the eastern part of the study area. The Lamar marsh-lagoon system is copmosed mostly of mudstone containing few, discontinuous sandstone bodies and extends westward from the Fayette-Walker barrier system. The Pickens-Tuscaloosa delta system extends southward from the southern limit of the Fayette-Walker barrier system and the Lamar marsh-lagoon. Sparse data from the Pickens-Tuscaloosa delta system suggest a northeast-southwest-trending sandstone interbedded with mudstone and coal.Item NRRI Library to House Materials Related to Copper-Nickel Study(1989-03-10) Sandy, John H.; Miller, PatriciaItem The Farnham Peat Collection: A Subject Catalog of the Peat Research Materials in the Natural Resources Library(1990-08-04) Sandy, John H.; Hauck, Barbara H.; Hendrickson, Susan R.; Weber, Frances A.Item Depositional History of the Smackover Formation, Appleton Field, Escambia County, Alabama(University of Alabama Libraries, 1992) Markland, Lisa Ann; University of Alabama TuscaloosaAppleton field is situated across two northwest-southeast trending, pre-Mesozoic "basement" highs near the updip limit of the Smackover Formation in the northern portion of the Conecuh embayment. Smackover deposition at Appleton field was influenced by both pre-Smackover paleotopography and variations in sea level.Item Revised classification and terminology of Palaeozoic stromatoporoids(Institute of Paleobiology, 1999) Stearn, Colin W.; Webby, Barry D.; Nestor, Heldur; Stock, Carl W.Palaeozoic stromatoporoids comprise an extinct class of non-spiculate poriferans that are represented as fossils by their basal carbonate skeleton. A revised terminology for the description of these fossils is presented. Seven orders (Labechiida, Clathrodictyida, Actinostromatida, Stromatoporellida, Stromatoporida, Syringostromatida, Amphiporida) are recognized. The following is recorded for each genus: (1) type species, catalogue number and depository of the primary holotype; (2) synonyms and their type species; (3) diagnosis; (4) stratigraphic range; (5) estimate of the number of species assigned to the genus; (6) stratigraphic and geographic distribution of the genus. Problems in the definition and recognition of the genus are briefly discussed in annotations. One hundred and nine genera are considered valid, or doubtfully valid. Fifty three genera are placed in synonymy. An additional 14 genera are considered to be of uncertain placement in the classification.Item Oxygen isotope record of the 1997-1998 El Nino in Peruvian sea catfish (Galeichthys peruvianus) otoliths(American Geophysical Union, 2002-10-11) Andrus, CFT; Crowe, DE; Romanek, CS; University System of Georgia; University of Georgia; United States Department of Energy (DOE); Savannah River Ecology Laboratory; University of Alabama Tuscaloosa[1] Sagittal otoliths of the Peruvian sea catfish Galeichthys peruvianus were collected from the north coast of Peru during and after the 1997-1998 El Nino. The otoliths were analyzed via laser microprobe and micromilling techniques for oxygen isotope composition through ontogeny to document their use as an El Nino-Southern Oscillation (ENSO) proxy. Results were compared to theoretical calculations for the delta(18)O of otolith aragonite using measured sea surface temperatures (SST) and delta(18)O values for local seawater assuming equilibrium oxygen isotope fractionation was achieved. All otoliths recorded the 1997-1998 El Nino event as well as seasonal temperature variations. These ENSO events were recorded in otolith aragonite as significant negative excursions in delta(18)O that reflected the increased temperature of local marine waters. The combined otolith data were used to create a 10-year SST record, including ENSO events and local seasonal temperature variation, validating the use of otolith delta(18)O as a temperature proxy.Item Seasonal Shell Growth and Longevity in Donax Variabilis from Northeastern Florida: Evidence from Oxygen Isotopes(2004) Jones, Douglas S.; Quitmyer, Irvy R.; Andrus, C. Fred T.; University of Alabama TuscaloosaThe variable coquina clam, Donax variabilis, is one of the most common inhabitants of exposed sandy beach intertidal and shallow subtidal zones in the southeastern United States. Its exceptional burrowing and migratory behaviors are well documented, as are its biogeograpbic distribution and phylogenetic relationships. However, basic life history parameters such as season and rate of shell growth and longevity are poorly constrained for this species, usually estimated from size-frequency analyses of sample populations. High-resolution sampling of individual D. variabilis shells, and analysis of the oxygen isotopic variation in these samples, provides an alternate method of assessing shell growth and longevity in this species with a high degree of precision. Comparison of isotopic paleotemperature profiles with local seawater temperatures in the northeastern Florida study region indicates rapid shell growth (>4 mm/month) during a life span of 3 to 5 months, substantially shorter than most previous estimates. Detailed analysis of two modern shells indicates growth during spring and summer whereas four Archaic period archaeological shells revealed a summer-autumn growth record. In all cases the largest archaeological shells were substantially bigger than the largest modern shells, reflecting a greater longevity by about 2 months. Although recruitment can be fairly continuous throughout the year, size-frequency analyses of D. variabilis in separate years at the same locality reveal substantial interannual differences in population dynamics.Item Seismic interpretation and structural restoration of a seismic profile through the Southern Appalachian thrust belt under Gulf Coastal Plain sediments(University of Alabama Libraries, 2007) Bailey, Ryan Michael; University of Alabama TuscaloosaIn the southern part of the Appalachian thrust belt, the thrust system is buried by Gulf Coastal Plain sediments; thus, directly studying this Paleozoic thrust belt is impossible. However, multi-channel seismic data and well log data are used to explore this thrust belt. In this region, Gulf Coastal Plain sediments cover the Paleozoic thrust belt that formed during the Ouachita and Alleghenian orogeny. Due to a lack of well control and limited availability of proprietary quality seismic reflection profiles, only a few other studies interpret subsurface structures beneath the Gulf Coastal Plain (Thomas, 1973; Thomas, 1989; Bally, 1983; Hale-Erlich and Coleman, 1993). Stratigraphic thicknesses in the thrust belt were derived from the Ethel M. Koch #1 well and in the Black Warrior Basin from the James W. Sterling 17-14 well. Two additional wells, the Willis #1 and Dollarhide #1 were used to identify the depth to formation tops within the interpretation. An 84 kilometer long seismic profile was depth-converted using a sonic log from the Koch well and then projected onto a straight line perpendicular to the Appalachian thrust belt which shortened the length of the line to 78 kilometers. Five main horizons were interpreted in two way travel time and depth-converted using interval velocities derived from synthetic seismograms and the sonic log in the Koch well. A 14 kilometer zone of poorly imaged seismic data within line segment 691-1 A may be the result of high velocity material juxtaposed with the base of the Coastal Plain sediments. Two interpretations, both incorporating forward-propagating sequences, were made. The depth of the upper detachment altered the structural style of the ramp anticline on thrust 1 from a fault bend fold in interpretation #1 to a fault propagation fold in interpretation #2. Consequently, the depth of the detachment along with the fault trace of thrust 2 effected the thickness of units incorporated in thrust 2 and the thickness and number of units incorporated in thrust 3. The lengths of the units are quantitative, while the actual positions are speculative. The flexural slip method and line length balancing was used to balance the cross sections. Shortening estimates range from 23 kilometers or 29% shortening in interpretation # 1 to 19 kilometers or 26% shortening in interpretation #2.Item Seismic velocity structure and depth-dependence of anisotropy in the Red Sea and Arabian shield from surface wave analysis(American Geophysical Union, 2008-10-14) Hansen, Samantha E.; Gaherty, James B.; Schwartz, Susan Y.; Rodgers, Arthur J.; Al-Amri, Abdullah M. S.; King Saud University; Columbia University; United States Department of Energy (DOE); Lawrence Livermore National Laboratory; University of California System; University of California Santa Cruz; University of Alabama TuscaloosaWe investigate the lithospheric and upper mantle shear wave velocity structure and the depth-dependence of anisotropy along the Red Sea and beneath the Arabian Peninsula using receiver function constraints and phase velocities of surface waves traversing two transects of stations from the Saudi Arabian National Digital Seismic Network. Frequency-dependent phase delays of fundamental-mode Love and Rayleigh waves, measured using a cross-correlation procedure, require very slow shear velocities and the presence of anisotropy to depths of at least 180 km in the upper mantle. Linearized inversion of these data produce path-averaged 1D radially anisotropic models with similar to 4% anisotropy in the lithosphere and across the lithosphere-asthenosphere boundary (LAB). Models with reasonable crustal velocities in which the mantle lithosphere is isotropic cannot satisfy the data. The lithosphere, which ranges in thickness from about 70 km near the Red Sea coast to about 90 km beneath the Arabian Shield, is underlain by a pronounced low-velocity zone with shear velocities as low as 4.1 km/s. Forward models of azimuthal anisotropy, which are constructed from previously determined shear wave splitting estimates, can reconcile surface and body wave observations of anisotropy. The low shear velocities extend to greater depth than those observed in other continental rift and oceanic ridge environments. The depth extent of these low velocities combined with the sharp velocity contrast across the LAB may indicate the influence of the Afar hot spot and the presence of partial melt beneath Arabia. The anisotropic signature primarily reflects a combination of plate- and density-driven flow associated with rifting processes in the Red Sea.Item Upper crustal shortening and forward modeling of the Himalayan fold-thrust belt along the Budhi-Gandaki river, central Nepal(University of Alabama Libraries, 2009) Khanal, Subodha; Robinson, D. M.; University of Alabama TuscaloosaGeologic mapping along the Budhi-Gandaki River in central Nepal reveals 6 significant structures: 1) South Tibetan Detachment system; 2) Main Central thrust; 3) Ramgarh thrust; 4) Lesser Himalayan duplex including the Trishuli thrust; 5) Main Boundary thrust; and 6) Main Frontal thrust system. A balanced cross-section between the South Tibetan Detachment system and Main Frontal thrust reveals that the region has a minimum total shortening of 76% or 420 km. The breakdown of the accommodation of shortening on each thrust is as follows: Main Central thrust - 115 km; Ramgarh thrust - 120 km; Lesser Himalayan duplex including the Trishuli thrust - 156 km; Main Boundary thrust - 10 km; Main Frontal thrust system - 19 km. In order to validate the balanced cross-section, a reconstruction program was used to forward model the system. By moving faults with appropriate amounts of displacement over a reasonable configuration of undeformed stratigraphy from the hinterland to foreland, the deformation of the Himalayan thrust belt along the Budhi-Gandaki River cross-section is reproduced. The forward modeling program moves hanging wall rock over stationary footwall rock using each individual fault identified in the balanced crosssection. Hanging wall rock deforms as it is thrust over footwall structures. Using forward modeling, the cross-section has a shortening estimate of 412 km or 75%. The two shortening estimates are virtually identical indicating the balanced cross-section along the Budi-Gandaki River is viable and admissible.Item Groundwater flow dynamics and contaminant transport to coastal waters under low recharge conditions: regional-scale study of the aquifer system underlying southern Baldwin County, Alabama(University of Alabama Libraries, 2009) Murgulet, Dorina; Tick, Geoffrey R.; University of Alabama TuscaloosaThis study examined the influence of drought conditions and increased hydrological stresses on the groundwater system flow dynamics, submarine groundwater discharge, and nitrate transport and discharge to the Gulf of Mexico. The results of these studies demonstrate that current stresses on the aquifer have led to significant saltwater intrusion and or direct infiltration into fresh groundwater, especially within the upper aquifers of the region. The nitrate and chloride data analyses reveal the persistent presence of multiple nitrate impacted zones within the study area. Stable isotope data support the hypothesis that nitrate in the investigated aquifers originates from the nitrification of ammonium in soils from a mixture of sources ranging from fertilizer to sewer and/or manure and that denitrification, the breakdown of nitrates to nitrogen gas, is not significant in the investigated aquifer system. Furthermore, groundwater isotope data indicates that water in the aquifer system of the study area is most likely to have originated from precipitation and soil infiltration through relatively localized recharge and that the aquifer system in the study area is highly dynamic, experiencing mixing of recent recharged waters with older, ambient groundwaters. The presence of low residence times and the absence of denitrification reveal the oxic character of this system. As a proxy for a number of contaminant types, the groundwater flow and transport model was used to simulate nitrate transport in response to variable-density groundwater flow. The simulation results indicate that in the investigated aquifer system complexities arise because groundwater flow dynamics and contaminant transport are additionally influenced by density variations that can occur from the incursion of saltwater. The model predicts that the Beach Sand and Gulf Shores Aquifers will be impacted by severe saltwater intrusion whereas the deeper 350 and 500-Foot Aquifers will experience no saltwater intrusion for the entire simulation period. Consequently, nitrate discharge to the Gulf of Mexico originates from the lower part of the aquifer system through submarine groundwater discharge. This research will serve as a tool which may be applied to other similar coastal systems for more effective management strategies.