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Geochemical Analysis Of The Chinchín Formation In Southern Ecuador, Katherine Ludwig 2019 Augustana College, Rock Island Illinois

Geochemical Analysis Of The Chinchín Formation In Southern Ecuador, Katherine Ludwig

Celebration of Learning

The subduction of the Nazca Plate under the South American Plate has led to the uplift of the majority of the Andes Mountains, but in Ecuador, the Nazca Plate subducts underneath the North Andes Plate, which then collides with the South American Plate. This tectonic setting has formed two parallel mountain chains as well as a complex series of basins between them. However, the formations that make up these basins are poorly understood. This study focuses on the Chinchín Formation, an ~3.5 km thick, volcanic formation that serves as the bedrock of the Quingeo Basin in southern Ecuador. This study …


Middle Miocene To Holocene History Of The Delacroix Island Fault System, Jarrett Leigh Levesh 2019 University of New Orleans

Middle Miocene To Holocene History Of The Delacroix Island Fault System, Jarrett Leigh Levesh

University of New Orleans Theses and Dissertations

An in-depth field study of the Delacroix Island producing field illustrates the evolution of the east-trending Delacroix Island Fault during the last 13 My. Well log correlations and 3-D seismic interpretation of 22 subsurface bio-stratigraphic horizons across the fault reveal variable stratigraphic thicknesses and displacement. Wells, with well log curve data as shallow as 31 m (100 ft) below the surface, were used to calculate interval thicknesses, expansion indices, sediment accumulation rates, burial history and magnitudes of displacement. Through these analyses, a correlation was found between the positioning of ancient Miocene depocenters over Delacroix Island and a period of increased …


Facies And Diagenesis Analyses Of The Fort Terrett Formation Of The Lower Cretaceous Edwards Group, Near Junction, Texas, Richard Alden Urwin Jr. 2019 Stephen F. Austin State University

Facies And Diagenesis Analyses Of The Fort Terrett Formation Of The Lower Cretaceous Edwards Group, Near Junction, Texas, Richard Alden Urwin Jr.

Electronic Theses and Dissertations

The Fort Terrett Formation was deposited on the western edge of the Comanche Shelf in central Texas. The predominate lithology of the Fort Terrett Formation is limestone which caps the hills that surround Junction, Texas. Deposition of the Fort Terrett Formation occurred within shallow, quiet waters during the Lower Cretaceous. Rose (1974) developed a general stratigraphic correlation and lithostratigraphic framework for the Cretaceous Shelf and established a regional correlation. Four stratigraphic divisions have been recognized in the Fort Terrett Formation. These are: a basal nodular unit, a burrowed unit, a dolomitic unit, and the Kirschberg evaporites. Wilkerson (2018) provided the …


Stratigraphy And Depositional Characterization Of The Moorefield Shale (Middle-Late Mississippian) In Its Type Area, Northeastern Arkansas (Eastern Arkoma Basin), Griffin Warner 2019 University of Arkansas, Fayetteville

Stratigraphy And Depositional Characterization Of The Moorefield Shale (Middle-Late Mississippian) In Its Type Area, Northeastern Arkansas (Eastern Arkoma Basin), Griffin Warner

Graduate Theses and Dissertations

The Moorefield Shale represents the Meramecian Series in the Eastern Arkoma Basin in northern Arkansas. Lying on the margin of the Mississippi Embayment and Reelfoot Rift, sequence stratigraphic interpretations have labelled the Moorefield Shale a lowstand wedge succeeding the Early Mississippian (Osagean) Boone Limestone conformably and overlain conformably by the Hindsville Limestone/Batesville Sandstone. The unit contains a basal brown-black limestone and succeeding brown-black phosphatic shale. The Moorefield Shale was deposited along the broad, stable cratonic platform on the southern flank of Laurasia, before it’s collision with Gondwanaland to form the supercontinent Pangea at the end of the Paleozoic. During this …


Fun In A Kansas Salt Mine, Robert F. Diffendal Jr 2019 University of Nebraska-Lincoln

Fun In A Kansas Salt Mine, Robert F. Diffendal Jr

Robert F. Diffendal, Jr., Publications

Most people probably do not know that salt deposits hundreds of feet thick lie buried beneath large parts of western Kansas, western Oklahoma and a small part of the northeastern Texas Panhandle. Native Americans and early European explorers found that where the salt deposits came near the land surface (for, example north of Hutchinson, Kansas) salt is dissolved by ground water and increases the salinity of rivers, streams, springs and ponds. This salty water was used as a salt source by these peoples. The Hutchinson Salt, a 275 million-year-old Middle Permian deposit, was discovered in an exploratory drill hole in …


Morphodynamic Modeling Of Fluvial Channel Fill And Avulsion Time Scales During Early Holocene Transgression, As Substantiated By The Incised Valley Stratigraphy Of The Trinity River, Texas, Kaitlin Moran, Jeffrey Nittrouer, Mauricio Perillo, Jorge Lorenzo Trueba, John Anderson 2019 Rice University

Morphodynamic Modeling Of Fluvial Channel Fill And Avulsion Time Scales During Early Holocene Transgression, As Substantiated By The Incised Valley Stratigraphy Of The Trinity River, Texas, Kaitlin Moran, Jeffrey Nittrouer, Mauricio Perillo, Jorge Lorenzo Trueba, John Anderson

Jorge Lorenzo-Trueba

The Trinity River system provides a natural laboratory for linking fluvial morphodynamics to stratigraphy produced by sea-level rise, because the sediments occupying the Trinity incised valley are well constrained in terms of timing of deposition and facies distribution. Herein, the Trinity River is modeled for a range of base-level rise rates, avulsion thresholds, and water discharges to explore the effects of backwater-induced in-channel sedimentation on channel avulsion. The findings are compared to observed sediment facies to evaluate the capability of a morphodynamic model to reproduce sediment deposition patterns. Base-level rise produces mobile locations of in-channel sedimentation and deltaic channel avulsions. …


Exploring The Role Of Organic Matter Accumulation On Delta Evolution, Jorge Lorenzo Trueba, Vaughan Voller, Chris Paola, Robert Twilley, Azure Bevington 2019 Montclair State University

Exploring The Role Of Organic Matter Accumulation On Delta Evolution, Jorge Lorenzo Trueba, Vaughan Voller, Chris Paola, Robert Twilley, Azure Bevington

Jorge Lorenzo-Trueba

We explore the role of plant matter accumulation in the sediment column in determining the response of fluvial-deltas to base-level rise and simple subsidence profiles. Making the assumption that delta building processes operate to preserve the geometry of the delta plain, we model organic sedimentation in terms of the plant matter accumulation and accommodation (space made for sediment deposition) rates. A spatial integration of the organic sedimentation, added to the known river sediment input, leads to a model of delta evolution that estimates the fraction of organic sediments preserved in the delta. The model predicts that the maximum organic fraction …


Lithostratigraphic Correlation Of Upper Paleozoic Sandstone Bodies In The Western United States With Special Emphasis On The Coconino Sandstone, John H. Whitmore 2019 Cedarville University

Lithostratigraphic Correlation Of Upper Paleozoic Sandstone Bodies In The Western United States With Special Emphasis On The Coconino Sandstone, John H. Whitmore

The Research and Scholarship Symposium (2013-2019)

The purpose of this project was to correlate Upper Paleozoic sandstone bodies of Pennsylvanian and Permian age across the western United States. The lateral extent of the Coconino Sandstone (Leonardian) was of particular interest; it is found in northern Arizona in places like Grand Canyon. Data was obtained from multiple sources including the AAPG’s COSUNA charts and data, the RMAG’s Geological Atlas of the Rocky Mountain Region and published papers from a variety of books and journals. About 60 generalized stratigraphic columns were collected, drawn and then correlated across the western United States. Some of the more well-known sandstones and …


Modeling Land Subsidence Using Insar And Airborne Electromagnetic Data, Ryan G. Smith, R. Knight 2019 Missouri University of Science and Technology

Modeling Land Subsidence Using Insar And Airborne Electromagnetic Data, Ryan G. Smith, R. Knight

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Land subsidence as a result of groundwater overpumping in the San Joaquin Valley, California, is associated with the loss of groundwater storage and aquifer contamination. Although the physical processes governing land subsidence are well understood, building predictive models of subsidence is challenging because so much subsurface information is required to do so accurately. For the first time, we integrate airborne electromagnetic data, representing the subsurface, with subsidence data, mapped by interferometric synthetic aperture radar (InSAR), to model deformation. By combining both data sets, we are able to solve for hydrologic and geophysical properties of the subsurface to effectively model the …


Exploring Geochemical Proxies For Identifying Cryptic Sequence Boundaries In The Geologic Past Using Modern Bahamian Analogues, Evan B. Magette 2019 Louisiana State University at Baton Rouge

Exploring Geochemical Proxies For Identifying Cryptic Sequence Boundaries In The Geologic Past Using Modern Bahamian Analogues, Evan B. Magette

LSU Master's Theses

Previous studies of carbonate diagenesis have suggested that bulk Sr concentrations and inorganic δ13C values may be a useful proxy for identifying cryptic sequence boundaries in meteorically altered limestones due to geochemical processes associated with carbonate mineral stabilization in cement precipitation in the meteoric diagenetic environment. However, it is possible that natural geochemical variation in sediments may produce geochemical shift which could be misinterpreted as a cryptic sequence boundary. To test this, the Two Pines roadcut containing a previously identified protosol on Eleuthera, Bahamas, which has been affected by vadose meteoric diagenesis was sampled for bulk geochemical analysis. …


Mississippian-Devonian Black Shales Of Kentucky: East-West Transect In Five Cores From The Appalachian Basin To The Illinois Basin, Patrick J. Gooding, Frank R. Ettensohn 2019 University of Kentucky

Mississippian-Devonian Black Shales Of Kentucky: East-West Transect In Five Cores From The Appalachian Basin To The Illinois Basin, Patrick J. Gooding, Frank R. Ettensohn

Kentucky Geological Survey Map and Chart

Devonian-Mississippian black shales are widespread across North America and underlie nearly 70 percent of Kentucky (Kepferle and Roen, 1981; Ettensohn and others, 1988). These black-shale units are among the most thoroughly investigated format ions in the commonwealth, because t hey have sourced most of t he conventional hydrocarbons (Gooding and Ettensohn, 2008; Gooding, 2013), have been major producers of gas in both the Illinois and Appalachian Basins, and have major potential as unconventional producers in both basins. In fact, maturation indicators such as vitrinite reflectance and total organic carbon, from both basins, show that the shales are most ly mature …


Effectiveness Of Four Water-Bearing Zones Of The Glacierized Basin In Meltwater Runoff Modeling, Umesh K. Haritashya 2019 University of Dayton

Effectiveness Of Four Water-Bearing Zones Of The Glacierized Basin In Meltwater Runoff Modeling, Umesh K. Haritashya

Umesh K. Haritashya

Meltwater runoff modeling from glacierized basins needs several input data, including total meltwater contributing area. This study utilizes optical remote sensing data to assess glacierized basins in the central Himalayas where snow and glaciers contribute substantially to the water resources. Result shows that there are four main water-bearing zones in the basin: (a) dry snow, (b) wet snow, (c) exposed glacial ice, and (d) debris-covered glacial ice, and it is possible to differentiate and map these zones and their spatio-temporal variations from satellite sensor data. These zones can then be incorporated in meltwater runoff modeling as separate entities because they …


Nebraska Statewide Groundwater-Level Monitoring Report 2018, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Michele M. Waszgis, Sue Olafsen Lackey, Robert Matthew Joeckel 2019 University of Nebraska-Lincoln

Nebraska Statewide Groundwater-Level Monitoring Report 2018, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Michele M. Waszgis, Sue Olafsen Lackey, Robert Matthew Joeckel

Conservation and Survey Division

The term “groundwater” has come to be all but synonymous with Nebraska. Nearly three-quarters of the total volume of the High Plains Aquifer lies beneath the State. Groundwater maintains our streams, our ecosystems, our people, and our vitally important agricultural economy. Nebraska’s total groundwater resource is vast, yet it is also vulnerable to natural and anthropogenic changes, necessitating a long-term commitment to wise management through informed decision making. Monitoring, studying, and reporting form the essential basis for such management and, ultimately, for meeting the myriad challenges presented by change.

The personnel of the Conservation and Survey Division (CSD) are pleased …


Informing Water Use Decision-Making For Waterfowl And Agricultural Production On A Ranch Along The North Platte River, Nebraska, Douglas R. Hallum P.G. 2019 University of Nebraska - Lincoln

Informing Water Use Decision-Making For Waterfowl And Agricultural Production On A Ranch Along The North Platte River, Nebraska, Douglas R. Hallum P.G.

Conservation and Survey Division

In 2014, operators of a ranch along the North Platte River approached Conservation and Survey Division seeking expertise to interpret data collected on their ranch. The interpretations inform ranch decisions to accomplish operators’ goals. This publication documents the work by: 1) characterizing the ranch, 2) summarizing data collected, 3) characterizing hydrogeology of the site and the adjacent reach, and 4) conceptualizing groundwater/surface water interaction.

The ranch is a recreation property and a migratory waterfowl refuge with a few general goals: 1) develop and maintain high-quality wet meadow habitat, 2) maximize the extent and duration of surface water on the property …


Modeling Land Subsidence Using Insar And Airborne Electromagnetic Data: Dataset, Ryan G. Smith, R. Knight 2019 Missouri University of Science and Technology

Modeling Land Subsidence Using Insar And Airborne Electromagnetic Data: Dataset, Ryan G. Smith, R. Knight

Research Data

Supporting dataset for article published in Water Resources Research, Volume 55, Issue 4, pages 2801-2819


Late Devonian Sedimentary Record Of Appalachian Tectonics And Erosion: Geochronology And Geochemistry Of Detrital Muscovite And Zircon From Central Pennsylvania Strata, Cole T. Gardner 2019 Bucknell University

Late Devonian Sedimentary Record Of Appalachian Tectonics And Erosion: Geochronology And Geochemistry Of Detrital Muscovite And Zircon From Central Pennsylvania Strata, Cole T. Gardner

Honors Theses

Foreland basin sediment deposition in North-Central Pennsylvania during Late Devonian time records erosion of hinterland source terranes exhumed during regional plate convergence, including the collisional Acadian orogeny. The Catskill clastic wedge preserves a coarsening-upwards stratigraphic succession from marine to fluvial environments associated with sediment progradation and sea-level regression, yet depositional timescales and quantitative provenance data are largely unconstrained.

Detailed facies analysis of eight outcrops spanning >2 km of stratigraphy in Lycoming Co., Pennsylvania documents distinct upsection changes, interpreted to reflect changes in depositional environments consistent with previous sedimentology of the Catskill clastic wedge. Stratigraphy displays a transition from nearshore marine …


Geology Of Southeastern Nebraska, Robert Matthew Joeckel, Dana Divine, Leslie M. Howard, Kathleen Cameron, Michele M. Waszgis 2019 University of Nebraska - Lincoln

Geology Of Southeastern Nebraska, Robert Matthew Joeckel, Dana Divine, Leslie M. Howard, Kathleen Cameron, Michele M. Waszgis

Conservation and Survey Division

No abstract provided.


Maps Showing The Physical Hydrogeology And Changes In Saturated Thickness (Predevelopment To Spring 2016 And Spring 2011 To Spring 2016) In The Middle Republican Natural Resources District, Southwestern Nebraska., Jesse T. Korus Dr., Leslie M. Howard 2019 University of Nebraska-Lincoln

Maps Showing The Physical Hydrogeology And Changes In Saturated Thickness (Predevelopment To Spring 2016 And Spring 2011 To Spring 2016) In The Middle Republican Natural Resources District, Southwestern Nebraska., Jesse T. Korus Dr., Leslie M. Howard

Conservation and Survey Division

This report accompanies fourteen new maps summarizing the hydrogeology and changes in saturated thickness in the Middle Republican Natural Resources District (MRNRD). The purpose of these maps is to assist the MRNRD in their groundwater management programs and in planning and installing an observation well network. Maps include:

• base of the principal aquifer;

• water table surfaces for predevelopment, Spring 2011, and Spring 2016;

• saturated thicknesses for predevelopment, Spring 2011, and Spring 2016;

• changes in saturated thickness (both in absolute magnitude and in percent) from predevelopment to Spring 2016 and from Spring 2011 to Spring 2016;

• …


Mapping And Reconstructing The Paleotsunami Record In Queule, South-Central Chile, Pedro I. Matos Llavona 2019 Central Washington University

Mapping And Reconstructing The Paleotsunami Record In Queule, South-Central Chile, Pedro I. Matos Llavona

All Master's Theses

Records of past tsunamis help constrain the long-term characteristics of megathrust earthquakes and elucidate the role of sea-level in the preservation of tsunami deposits. Near Queule, south-central Chile (39.3˚S, 73.2˚W), three sand layers interpreted as tsunami deposits are interbedded with dark, organic-rich, silt deposits along a tidal channel landward of a sand spit capped by eolian sand dunes. The uppermost sand layer is attributed to the tsunami from the Mw 9.5 1960 earthquake. The sand layer is widespread, tabular, oxidized, thins landward, and generally occurs at a depth of <20 cm. The spatial distribution of the deposit corresponds closely with the extent of the 1960 tsunami sand on 1961 aerial photographs. We computed numerical simulations of the 1960 tsunami in Queule using the GeoClaw finite-slip hydrodynamic model based on three published earthquake sources. The simulations showed inundation up to 4km inland that overtopped the coastal dunes; agreeing with historical documentation and testimonies of 1960 tsunami survivors. Stratigraphically below the 1960 tsunami deposit are two tabular, landward-thinning sand layers with sharp lower contacts above silty organic-rich layers. Combined radiocarbon ages of seeds, charcoal and wood fragments found at the contacts with the underlying organic layers yielded ages of 5460-5320 and 5990-5910 cal. years BP. These sand layers have similar distribution patterns to the 1960 sand layer, but are finer grained, thinner and less oxidized. Below this sequence of interbedded tsunami sands and silty organic layers there is an abrupt contact underlain by a distinct sequence of four inorganic silt layers alternating with dark brown organic-rich silts, which are older than 6280-6110 cal. years BP. The deepest studied layer is a thick, fine, gray sand. We interpret the gray sand as a submarine environment during the mid-Holocene sea-level high stand, and the alternating inorganic and organic silts as tidal to shallow sub-tidal environments, possibly indicating co-seismic land-level changes. Gradual sea level fall after the deposition of the two paleotsunami sand deposits that changed the geomorphology of the coast and limited the accommodation space necessary to preserve additional overwash sediments could explain the 5000-year hiatus with no evidence of earthquakes or tsunamis. Further research will offer possible explanations for the exception of the 1960 tsunami in breaking this long-term pattern.


Structural Style And Stratigraphic Architecture Of The Northeastern Brooks Range, Alaska, Benjamin G. Johnson 2019 West Virginia University

Structural Style And Stratigraphic Architecture Of The Northeastern Brooks Range, Alaska, Benjamin G. Johnson

Graduate Theses, Dissertations, and Problem Reports

The Arctic Alaska–Chukotka microplate is a large Mesozoic–Cenozoic composite terrane that resides at the northern limit of the North American Cordillera. Although its Mesozoic origins are assuredly linked to the opening of the Amerasian Basin of the Arctic Ocean, its Paleozoic origins can be linked to at least three separate paleocontinents, including northern Laurentia, Baltica, and Siberia. Across the Arctic Alaska portion of the microplate, an internal, mid-Paleozoic suture zone presumably separates rocks of the North Slope subterrane (Laurentian affinity) from a collection of smaller subterranes in the southern Brooks Range and Seward Peninsula (Baltic affinity).

The mountains of the …


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