Geology Commons^™

Size-Frequency Distribution Of Orbitolina Texana Foraminifera, Jeremy Foote

Undergraduate Review

This study examined size-frequency distributions for an extinct Cretaceous-age benthic foraminifera called Orbitolina Texana in order to determine the health of this foram community during the time of accumulation. Forams were collected from limestone outcrops of the Glen Rose Formation in central Texas. Based on paleontological and sedimentological evidence, Orbitolina Texana are interpreted to be a shallow water (<10 m) benthic organism that was most abundant in back-reef environments. Sizefrequency distributions were generated from the diameters of 4,245 Orbitolina Texana fossils. The results indicate that the Orbitolina Texana population is characterized by a Gaussian (normal) size distribution. Size-frequency distributions of fossilized foraminifera in the stratigraphic record are controlled by two principle variables; environmental controls that affect the biology of the organisms (e.g., environmental stressors, like food availability and ambient conditions) and sedimentological controls that affect how the organisms are distributed (e.g., hydrodynamic parameters, like waves and currents). Based on a sedimentological characterization of the host limestone including lack of high-energy sedimentary structures, high mud content and back-reef position on the depositional profile, hydrodynamic parameters are interpreted to not have exerted a significant effect on the distribution of the forams preserved in the rock record. As such, the biological controls are interpreted to be the dominate control on the foram sizefrequency distribution. Therefore, the Gaussian (normal) size distribution suggests that the mortality rate is independent of size/age, which is classified as Type II survivorship. As this result is consistent with similar taxon, the results indicate that this Orbitolina Texana population was a healthy biologic community, despite the low biologic diversity observed in the Glen Rose Formation.

Slope Stability Analysis Of Mount Meager, South-Western British Columbia, Canada, Rachel M. Hetherington

Dissertations, Master's Theses and Master's Reports - Open

The Mount Meager Volcanic Complex (MMVC) in south-western British Columbia is a potentially active, hydrothermally altered massif comprising a series of steep, glaciated peaks. Climatic conditions and glacial retreat has led to the further weathering, exposure and de-buttressing of steep slopes composed of weak, unconsolidated material. This has resulted in an increased frequency of landslide events over the past few decades, many of which have dammed the rivers bordering the Complex. The breach of these debris dams presents a risk of flooding to the downstream communities. Preliminary mapping showed there are numerous sites around the Complex where future failure could …

The Inky Story Of The Dinky Oak Gall, Ken Sulak

United States Geological Survey: Staff Publications

Maybe you have noticed these little spheres before – but did not give them much thought. Or maybe, you puzzled: What are these wooden pearls? How did they get there? Well, a tiny wasp, called the pea galler wasp or gallfly, Belonocnema treatae, is the culprit. The diminutive female gallfly (one of nearly a thousand species in the gall wasp family Cynipidae), about the size of a fire ant, lays eggs on a freshly budded live oak leaf in spring. When the larva hatches, it produces a chemical that induces the oak to enclose it in a protective and …

Integrating Land Cover Modeling And Adaptive Management To Conserve Endangered Species And Reduce Catastrophic Fire Risk, David Breininger, Brean Duncan, Mitchell J. Eaton, Fred Johnson, James Nichols

United States Geological Survey: Staff Publications

Land cover modeling is used to inform land management, but most often via a two-step process, where science informs how management alternatives can influence resources, and then, decision makers can use this information to make decisions. A more efficient process is to directly integrate science and decision-making, where science allows us to learn in order to better accomplish management objectives and is developed to address specific decisions. Co-development of management and science is especially productive when decisions are complicated by multiple objectives and impeded by uncertainty. Multiple objectives can be met by the specification of tradeoffs, and relevant uncertainty can …

Interpreting The Paleozoogeography And Sea Level History Of Thermally Anomalous Marine Terrace Faunas: A Case Study From The Last Interglacial Complex Of San Clemente Island, California, Daniel R. Muhs, Lindsey T. Groves, R. Randall Schumann

United States Geological Survey: Publications

Marine invertebrate faunas with mixtures of extralimital southern and extralimital northern faunal elements, called thermally anomalous faunas, have been recognized for more than a century in the Quaternary marine terrace record of the Pacific Coast of North America. Although many mechanisms have been proposed to explain this phenomenon, no single explanation seems to be applicable to all localities where thermally anomalous faunas have been observed. Here, we describe one such thermally anomalous fossil fauna that was studied on the second emergent marine terrace at Eel Point on San Clemente Island. The Eel Point terrace complex is a composite feature, consisting …

Identifying Sources Of Aeolian Mineral Dust: Present And Past, Daniel R. Muhs, Joseph M. Prospero, Matthew C. Baddock, Thomas E. Gill

United States Geological Survey: Publications

Aeolian mineral dust is an important component of the Earth’s environmental systems, playing roles in the planetary radiation balance, as a source of fertilizer for biota in both terrestrial and marine realms and as an archive for understanding atmospheric circulation and paleoclimate in the geologic past. Crucial to understanding all of these roles of dust is the identification of dust sources. Here we review the methods used to identify dust sources active at present and in the past. Contemporary dust sources, produced by both glaciogenic and non-glaciogenic processes, can be readily identified by the use of Earth-orbiting satellites. These data …

Coastal Geology And Recent Origins For Sand Point, Lake Superior, Timothy G. Fisher, David E. Krantz, Mario R. Castaneda, Walter L. Loope, Harry M. Jol, Ronald J. Goble, Melinda C. Higley, Samantha Dewald, Paul R. Hanson

Department of Earth and Atmospheric Sciences: Faculty Publications

Sand Point is a small cuspate foreland located along the southeastern shore of Lake Superior within Pictured Rocks National Lakeshore near Munising, Michigan. Park managers’ concerns for the integrity of historic buildings at the northern periphery of the point during the rising lake levels in the mid-1980s greatly elevated the priority of research into the geomorphic history and age of Sand Point. To pursue this priority, we recovered sediment cores from four ponds on Sand Point, assessed subsurface stratigraphy onshore and offshore using geophysical techniques, and interpreted the chronology of events using radiocarbon and luminescence dating. Sand Point formed at …

Burrow Morphology Of The Land Crab Gecarcinus Lateralis And The Ghost Crab Ocypode Quadrata On San Salvador Island, The Bahamas: Comparisons And Palaeoenvironmental Implications, Koji Seike, H. Allen Curran

Geosciences: Faculty Publications

Burrow morphologies of the land crab Gecarcinus lateralis and the ghost crab Ocypode quadrata were investigated on East Beach, San Salvador Island, The Bahamas, with the goals of critical comparison of their morphologies and of clarifying and advancing their palaeoenvironmental usefulness. In comparing land crab burrows to those of the ghost crab, the former are simpler but more variable in overall shape. G. lateralis burrows have a more compressed form in the transverse section of the burrow shaft and possess lower (more horizontal) shaft inclination than those of O. quadrata. In the late Holocene backshore and dune deposits on San …

Petrology And Pedology Of The Gordon Natural Area: A Collaborative Service-Learning Project, Martin Helmke, Corinne Trice, Leeann Srogi

Gordon Natural Area Geology Studies Documents

No abstract provided.

Nebraska Statewide Groundwater-Level Monitoring Report 2014, A. R. Young, M. E. Burbach, L. M. Howard

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Basalt Ring Formations Of The Columbia River Plateau, Skye Schillhammer, Carly Sorensen, Ted Uecker, Natasha Garland

2014 Symposium

Unusual basalt ring formations are located about 6 miles north of Odessa, WA as part of the expansive Columbia River Basalt Group. There are over 100 crater-like structures that range in size from 50-500 meters in diameter and span a 60 kilometer area of the channeled scablands. These structures are enigmatic due to the erosion of surficial features by the Missoula Floods, and due to their association with a magnetic anomaly as evidenced by an aerial geophysical survey. Since the 1970s, multiple geologists have proposed conflicting formational mechanisms for the rings, including hydrothermal explosions and sag flows. Over the past …

Geophysical Investigation Of Hot Springs In The Vicinity Of Shoshone, California, Felix Dziedzorm Ziwu

Open Access Theses & Dissertations

Magnetic and gravity surveys were conducted in the vicinity of Shoshone, California to test a hypothesis from investigating hotsprings within Tecopa and Saratoga which states that deep faults must intersect with a specific orientation relative to the regional stress field in order to create hot springs along the Amargosa River.

Three isolated basalt flows with different gravity and magnetic properties were identified near the Shoshone hot spring. Two of the flows have very low magnetic anomalies and the remaining one has a high magnetic anomaly. The high magnetic anomaly basalt flow also has a significantly higher Bouguer anomaly than the …

Central Cascadia Subduction Zone Creep, Gina M. Schmalzle, Robert Mccaffrey, Kenneth C. Creager

Geology Faculty Publications and Presentations

Central Cascadia between 43ºN and 46ºN has reduced interseismic uplift observed in geodetic data and coseismic subsidence seen in multiple thrust earthquakes, suggesting elevated persistent fault creep in this section of the subduction zone. We estimate subduction thrust "decade-scale" locking and crustal block rotations from three-component continuous Global Positioning System (GPS) time series from 1997 to 2013, as well as 80 year tide gauge and leveling-derived uplift rates. Geodetic observations indicatecoastal central Oregon is rising at a slower rate than coastal Washington, southern Oregon and northern California. Modeled locking distributions suggest a wide locking transition zone that extends inland undercentral …

Sedimentologic, Stratigraphic, And Diagenetic Analysis Of Microbialite-Bearing Lacustrine Rift Sequence Within The Lower Cretaceous Yucca Formation, Indio Mountains, West Texas, Xiaowei Li

Open Access Theses & Dissertations

This study sedimentologically, stratigraphically, and diagenetically analyzed strata of the upper member of the Lower Cretaceous Yucca Formation in the Indio Mountains, West Texas in order to develop an outcrop-based analog model for similar facies that form major hydrocarbon reservoirs in the Pre-salt rift basins of the South Atlantic margin. The lower Cretaceous strata of the Indio Mountains were deposited in rift basins that formed along the eastern margin of the Chihuahua Trough under similar greenhouse climate conditions as the South Atlantic basins.

Eleven lithofacies are recognized from the upper member of the Yucca Formation to the base of the …

Exploring The Hydrogeologic Controls On Brackish Water And Its Suitability For Use In Hydraulic Fracturing: The Dockum Aquifer, Midland Basin, Texas, Francisco Ruben Reyes

Open Access Theses & Dissertations

Water scarcity in arid regions can limit or impede certain hydrocarbon production activities, such as hydraulic fracturing and well drilling. The Midland Basin, a major oil-producing area in semi-arid far west Texas and the eastern sub-basin of the Permian Basin, is already impacted by limited freshwater availability. A typical tight oil well in the Midland Basin requires ~3.8–11.4 × 103 m3 of water per fracture treatment (Nicot et al., 2012). Despite draught conditions and limited resources, data for 2011 indicate freshwater comprises ~70% of the water used in hydraulic fracturing in the Midland basin. Thus, the Midland Basin represents an …

Mapping Technologically And Economically Important Materials At Lunar And Terrestrial Sites Using Moon Mineralogy Mapper (M3) And Advanced Spaceborne Thermal Emission And Reflection Radiometer (Aster) Data, Douglas L. Standart

Open Access Theses & Dissertations

This Dissertation comprises three distinct research projects, all of which employ the use of remote sensing and digital image processing methods for the discovery and characterization of mineral resources. Two of the research projects focus on the use of hyperspectral data to identify water and ilmenite on the lunar surface. The third research project involves the use of multispectral data to map alunite in copper porphyry and epithermal silver-gold deposits. Our approach to these problems result in innovative algorithms and geological interpretations that are of use to both planetary science and exploration and the terrestrial mineral industry.

Project I: Towards …

Kentucky Geological Survey Landslide Inventory: From Design To Application, Matthew M. Crawford

Information Circular--KGS

The Kentucky Geological Survey is compiling a landslide inventory database to better document the distribution and geologic context of Kentucky’s landslides. The database provides users with easy access to landslide information, raises awareness of landslide causes, and will help prevent property damage or injury. The database was used to create an online landslide information map, which provides online access to landslide data and gives users the ability to customize the map using other data layers pertinent to landslides. The database design is based on common attributes collected by other states with active inventories and landslide hazard programs, as well as …

Geology Of The Kentucky Geological Survey Marvin Blan No. 1 Well, East-Central Hancock County, Kentucky, J. Richard Bowersox, David A. Williams

Report of Investigations--KGS

The Kentucky Geological Survey’s Marvin Blan No. 1 well was drilled in east-central Hancock County, Ky., about 4 mi southwest of the Ohio River, to demonstrate CO₂ injection in the Western Kentucky Coal Field, following the mandate and partial funding from Kentucky’s House Bill 1, August 2007. Installation of a groundwater monitoring well was required as a condition of obtaining a U.S. Environmental Protection Agency Underground Injection Control Class V Permit prior to drilling the Blan well; however, no groundwater was encountered under the Blan well site. The groundwater monitoring well was immediately plugged and abandoned in accordance with …

Hydrogeologic Investigations Of Pavement Subsidence In The Cumberland Gap Tunnel, James S. Dinger, James C. Currens, Junfeng Zhu, Steven E. Webb, Brad W. Rister, R. C. Graves, David L. Allen, Tim C. Scully

Report of Investigations--KGS

Cumberland Gap Tunnel was constructed under Cumberland Gap National Historical Park in 1996 to improve transportation on a segment of U.S. 25E, connecting Kentucky and Tennessee and restoring Cumberland Gap to its historical appearance.

The concrete pavement in the tunnel started to subside in 2001. Ground penetrating radar surveys revealed voids in many areas of the limestone roadbed aggregate beneath the pavement. To investigate possible hydrogeologic processes that may have caused favorable conditions for voids to form in the aggregate, we studied geology, groundwater flow, and groundwater chemistry in the tunnel using a variety of methods, including bore drilling, packer …

Metamorphism Of Cretaceous Standstones By Natural Coal-Fires, San Rafael Swell, Utah, Alexa R. Zilberfarb

Scripps Senior Theses

Underground coal fires commonly metamorphose or melt surrounding rocks at temperatures exceeding 1000°C. Numerous “baked” sandstone clinker deposits occur in the Cretaceous sedimentary rocks exposed in the San Rafael Swell, UT. This study examines clinker in three main localities: 1) East Carbon, UT, 2) Helper, UT, and 3) Emery, UT. The extent of pyrometamorphism in these areas is variably developed, but reached high enough temperature in Helper, UT to initiate melting and the production of paralavas. These paralavas were examined compositionally and mineralogically to determine melting conditions, peak temperatures, and mobility of different metals as a result of pyrometamorphism. X-ray …