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Full-Text Articles in Tectonics and Structure

Geochemical Analysis Of Recent Volcanic Ash Blanketing Barbados And Constraints On Magma Composition (V32e-0112), Nazrul I. Khandaker, Krishna Mahabir, Surendranauth Mahabir, Lloyd Kiefer, Juan C. Campo, Andrew M. Singh Oct 2022

Geochemical Analysis Of Recent Volcanic Ash Blanketing Barbados And Constraints On Magma Composition (V32e-0112), Nazrul I. Khandaker, Krishna Mahabir, Surendranauth Mahabir, Lloyd Kiefer, Juan C. Campo, Andrew M. Singh

Publications and Research

Preliminary field and geochemical investigations were conducted on ash samples from Barbados to chemically characterize and decipher magma chemistry associated with a recent volcanic event. A thick plume of volcanic ash from the La Soufriere Volcano in St Vincent, which erupted on April 9, 2021, caused lower visibility due to ash clouds which engulfed the region for some time. Three authors from the research team visited Barbados during the summer subsequent and completed a reconnaissance investigation on recent ashfall. St Vincent is a small volcanic island in the Eastern Caribbean and lies in the southern part of the Lesser Antilles …


Integrating Remote Digital Tools Into Post-Pandemic Geologic Fieldwork To Effectively Disseminate Content Delivery And Assist In Overall Understanding Of Various Geologic Phenomena: Summer 2022 Field Mapping Exercises, Nazrul I. Khandaker Oct 2022

Integrating Remote Digital Tools Into Post-Pandemic Geologic Fieldwork To Effectively Disseminate Content Delivery And Assist In Overall Understanding Of Various Geologic Phenomena: Summer 2022 Field Mapping Exercises, Nazrul I. Khandaker

Publications and Research

INTEGRATING REMOTE DIGITAL TOOLS INTO POST-PANDEMIC GEOLOGIC FIELDWORK TO EFFECTIVELY DISSEMINATE CONTENT DELIVERY AND ASSIST IN OVERALL UNDERSTANDING OF VARIOUS GEOLOGIC PHENOMENA: SUMMER 2022 FIELD MAPPING EXERCISES

SHAMI, Malek, BETHEL, Cherise, NUNEZ, Eddy, RAYHAN, Salam, KHANDAKER, Nazrul and CABAROY, Charren C.

Geological Society of America Abstracts with Programs. Vol 54, No. 5, https://doi.org/10.1130/abs/2022AM-379779

SHAMI, Malek1, BETHEL, Cherise2, NUNEZ, Eddy3, RAYHAN, Salam3, KHANDAKER, Nazrul2 and CABAROY, Charren C.1, (1)Geology Discipline, AC-2F09, York College of CUNY, 9420 Guy R. Brewer Blvd., Jamaica, NY 11451, (2)Geology Discipline, York College of CUNY, …


Coulomb Stress Changes And Magnitude-Frequency Distribution For Lake Van Region, Hamdi Alkan, Erdem Bayrak Aug 2022

Coulomb Stress Changes And Magnitude-Frequency Distribution For Lake Van Region, Hamdi Alkan, Erdem Bayrak

Bulletin of the Mineral Research and Exploration

The tectonic structure of Türkiye is under the influence of Arabian, Eurasian, African, and Anatolian plates. Lake Van region, located in eastern Türkiye, has been exposed to many devastating earthquakes in historical and instrumental periods. In this paper, using regional earthquakes, the tectonic stress variation of Lake Van region was investigated using the Coulomb stress change and the b-value distribution. 83 earthquakes that occurred between 2000 and 2020 are used to calculate the Coulomb stress change, while 17815 earthquakes that occurred between 1903 and 2021 are used to calculate the b-value distribution. Coulomb stress change gives an idea about the …


A Graph Method For Interpretation Of Magnetic Anomalies Over 2d Dikes And Vertical Faults, İbrahim Kara, Oya Tarhan Bal, Anisya B.Tekkeli̇ Aug 2022

A Graph Method For Interpretation Of Magnetic Anomalies Over 2d Dikes And Vertical Faults, İbrahim Kara, Oya Tarhan Bal, Anisya B.Tekkeli̇

Bulletin of the Mineral Research and Exploration

Simple geometric assumptions for dikes and faults are often used for interpreting the parameters of these structures from magnetic anomalies. The magnetic anomaly of a 2D dike or a vertical fault consists of two components; one with even and the other with odd symmetries. The function resulting from the ratio of the even and odd components is independent from the amplitude coefficient. The abscissa of the half-maximum of the even component and the maximum of the odd component of a dike or a vertical fault is related to its depth and its half-width. Incorporating this relation into the corresponding equations …


Antler Foreland Basin Evolution Recorded In Detrital Zircon U-Pb Geochronology, James Duncan Aug 2022

Antler Foreland Basin Evolution Recorded In Detrital Zircon U-Pb Geochronology, James Duncan

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Antler orogeny was a Devonian-Mississippian (375-320 Ma) mountain building event that occurred along the western Laurentian margin. The initiation of the Antler orogeny is marked by the emplacement of the Roberts Mountain Allochthon (RMA) that thrust Cambrian-Devonian deep water marine siliciclastic rocks 100 km eastward onto the western Laurentian margin. Shortening related to the Antler orogeny deformed RMA strata and caused a flexural response in the continental crust that resulted in the formation of the adjacent Antler Foreland basin. The paleogeographic history of the RMA strata and tectonic drivers for the Antler orogeny are still debated. Proposed models suggest …


Kinematic And Vorticity Analysis Of The Slide Lake And Homestake Shear Zones, Central Colorado, Carsen T. Adams Aug 2022

Kinematic And Vorticity Analysis Of The Slide Lake And Homestake Shear Zones, Central Colorado, Carsen T. Adams

Masters Theses

Kinematic and quantitative vorticity analysis of the Homestake shear zone (HSZ) and the Slide Lake shear zone (SLSZ) in central Colorado provide further insight into crustal processes that controlled deformation within the Colorado Mineral Belt (CMB) shear zone system throughout the Proterozoic. Evaluating vorticity, that is, the relative contributions of pure to simple shear in sheared rocks, is crucial to understanding lithospheric tectonic evolution and allows for kinematic modeling of shear zone development at a variety of scales. Moreover, novel vorticity analyses involve determining the orientation of the vorticity vector and vorticity normal surface which can give insight into shear …


Response Of Surface And Atmospheric Parameters Associated With The Iran M 7.3 Earthquake, Feng Jing, Ramesh P. Singh Jul 2022

Response Of Surface And Atmospheric Parameters Associated With The Iran M 7.3 Earthquake, Feng Jing, Ramesh P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Multiparameter observed from satellite, including microwave brightness temperature, skin temperature, air temperature, and carbon monoxide, have been analyzed to identify the anomalous signals associated with the M 7.3 Iran earthquake of November 12, 2017. Besides removing the multiyear variability of parameters as background, the effect of surface and atmosphere of a dust storm event in Middle East region during October 29–November 1 is considered to distinguish the possible anomalies associated with the earthquake. The characteristic behaviors of surface and atmospheric parameters clearly show the signals associated with the M 7.3 earthquake and the dust storm event. The multiple parameters at …


Deformation Conditions Of Quartz-Rich Mylonites Of The Grenville Front Tectonic Zone And Application To The Crustal Strength, Xueke Chang Jun 2022

Deformation Conditions Of Quartz-Rich Mylonites Of The Grenville Front Tectonic Zone And Application To The Crustal Strength, Xueke Chang

Electronic Thesis and Dissertation Repository

This thesis analyzes a suite of mylonites from the Grenville Front shear zone exposed southeast of Sudbury, Ontario. Lattice preferred orientations, titanium-in-quartz thermometer, and dynamically recrystallized grain size piezometer measurements were applied to obtain the deformation mechanisms, deformation temperatures (T), and differential stresses (σ), respectively. Results show that these mylonites were formed in the shear zone during the terminal stage of the Grenville Orogeny. The dominant deformation mechanism is by regime 2 dislocation creep. The deformation temperature is between 425-567 °C, and the differential stress is between 56-133 MPa. These results are discussed in the context of wet quartzite flow …


Emplacement Of The Dadeville Complex Of The Southernmost Inner Piedmont Within The 7.5 Min. Cusseta Quadrangle, Chambers County, Alabama: Channel Flow, Klippe Kinematics, Or Orogen Parallel Translation, Timothy Black Jun 2022

Emplacement Of The Dadeville Complex Of The Southernmost Inner Piedmont Within The 7.5 Min. Cusseta Quadrangle, Chambers County, Alabama: Channel Flow, Klippe Kinematics, Or Orogen Parallel Translation, Timothy Black

Master's Theses

The Appalachian Mountains have a complex geologic history spanning three orogenic periods, the Taconic, the Acadian/Neoacadian, and Alleghanian orogenies. The Inner Piedmont of the Appalachian Mountains within Alabama contains two distinct lithologic complexes, the Dadeville Complex, and the Opelika Complex separated by the Stonewall Line. These complexes were formed during an arc-back arc fringing system during the Taconic orogeny and emplaced and recorded peak metamorphism during the Acadian orogeny.

The Dadeville Complex is an allochthonous arc terrain built on extended Laurentian crust. The mode of transportation and accretion after formation is not well understood, which has implications for the role …


Bathymetry Based Modeling Of Subaxial Magma Flows Under The Mid-Atlantic Ridge, 0 To 30° N, Adam R. Tjoelker, Neil Van Kanegan, Simon Detmer, C. Renee Sparks Jun 2022

Bathymetry Based Modeling Of Subaxial Magma Flows Under The Mid-Atlantic Ridge, 0 To 30° N, Adam R. Tjoelker, Neil Van Kanegan, Simon Detmer, C. Renee Sparks

The Compass: Earth Science Journal of Sigma Gamma Epsilon

Fracture patterns of the Mid-Atlantic Ridge (MAR) provide evidence of tectonic forces related to divergence and magma upwelling at the ridge axis. In this study, we focus on the MAR from 0 to 30° N, where the N-S ridge exhibits slow spreading rates (2-4 cm/yr) and pronounced axial topography. Ridge segments and transform faults identified in bathymetry data were analyzed for strike orientation and axial depth profiles. Azimuths of transform faults and ridge segments exhibit increasing clockwise rotation with latitude, and all have left lateral displacement. Bathymetric sampling along ridge segments occurred at 9 km intervals with 20 km sampling …


Investigating The Thermodynamics And Seismic Profile Of The Europan Hydrosphere Through Pure-Water Modeling And Saltwater Experiments, Samantha Rosenfeld Jun 2022

Investigating The Thermodynamics And Seismic Profile Of The Europan Hydrosphere Through Pure-Water Modeling And Saltwater Experiments, Samantha Rosenfeld

Honors Theses

We explore the properties of the hydrosphere on Europa involving both a modeling technique and experimental methods. We perform a computational analysis of the thermodynamic properties for an ideal, pure-water Europan ice shell using a Python programming framework called SeaFreeze. We create four models assuming surface temperatures of either 50 K or 140 K and ice shell thicknesses of either 3 km or 30 km. We observe mostly linear trends for the density and seismic wave velocities with respect to depth and find that surface temperature has the greatest effect on the models. Simultaneously, we experimentally investigate the phase diagram …


Correlations Between The Rotations And Magnetospheres Of The Terrestrial Planets And The Sun's Formation In Our Solar System, Fred J. Cadieu May 2022

Correlations Between The Rotations And Magnetospheres Of The Terrestrial Planets And The Sun's Formation In Our Solar System, Fred J. Cadieu

Publications and Research

Correlations between the rotations of the terrestrial planets in our solar system and the magnetic field of the Sun have been previously noted. These correlations account for the opposite rotation of Venus as a result of the magnetic field of the Sun being dragged across the conducting core of Venus. Currently the Sun’s magnetic field is not sufficiently strong to account for the proposed correlations. But recently meteorite paleomagnetism measurements have indicated that during the Sun’s formation the magnetic field of the Sun was of sufficient strength to have resulted in the observed correlations. As a part of these correlations …


Pronounced Changes In Thermal Signals Associated With The Madoi (China) M 7.3 Earthquake From Passive Microwave And Infrared Satellite Data, Feng Jing, Lu Zhang, Ramesh P. Singh May 2022

Pronounced Changes In Thermal Signals Associated With The Madoi (China) M 7.3 Earthquake From Passive Microwave And Infrared Satellite Data, Feng Jing, Lu Zhang, Ramesh P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Thermal variations in surface and atmosphere observed from multiple satellites prior to strong earthquakes have been widely reported ever since seismic thermal anomalies were discovered three decades ago. These thermal changes are related to stress accumulation caused by the tectonic activities in the final stage of earthquake preparation. In the present paper, we focused on the thermal changes associated with the 2021 Madoi M 7.3 earthquake in China and analyzed the temporal and spatial evolution of the Index of Microwave Radiation Anomaly (IMRA) and the Index of Longwave Radiation Anomaly (ILRA) based on 8-year microwave brightness temperature (MWBT) and 14-year …


Processing Seismic, Gravity And Magnetic Data Over Diebold Knoll On Juan De Fuca Plate, Md Ariful Islam, Irina Filina Apr 2022

Processing Seismic, Gravity And Magnetic Data Over Diebold Knoll On Juan De Fuca Plate, Md Ariful Islam, Irina Filina

UNL Student Research Days Posters, Graduate

The Juan de Fuca plate is subducting beneath the North American plate along the Cascadia Subduction Zone. The CSZ is associated with multiple earthquakes, although compared to other subduction zones, it is less active. Many studies suggest that subduction will cause major mega thrust earthquake in near future, while others oppose this view. This project is focused on the Diebold Knoll on the JdF plate Various geophysical methods will be integrated to determine its origin and tectonic history.


Influence Of Bedrock Erodibility On Orogen Evolution In Collisional Systems And Implications For Geodynamic Models, Stephanie Ann Sparks Jan 2022

Influence Of Bedrock Erodibility On Orogen Evolution In Collisional Systems And Implications For Geodynamic Models, Stephanie Ann Sparks

Theses and Dissertations--Earth and Environmental Sciences

Theoretical and numerical geodynamic models of continental collisional systems often involve, either explicitly or implicitly, a necessary yet complicated dependence between tectonics and erosion; however, the exact nature of these relationships remains elusive and controversial. In such models for the Himalayan-Tibetan (H-T) collisional orogen, surface processes are theorized or in some cases required to play an essential role in modulating critical processes active in the evolution of that system. To investigate, at least to first order. these interactions between climate and tectonics, we generate a simplified landscape evolution model of an actively uplifting orogenic wedge acted upon by surface processes. …


Syn- To Post-Orogenic Evolution Of Collisional Mountain Systems: Investigating The Potential For Crustal Flow Using Thermochronology And Numerical Models, Brandon Spencer Jan 2022

Syn- To Post-Orogenic Evolution Of Collisional Mountain Systems: Investigating The Potential For Crustal Flow Using Thermochronology And Numerical Models, Brandon Spencer

Theses and Dissertations--Earth and Environmental Sciences

This dissertation is composed of three distinct manuscripts which collectively investigate processes that contribute to the late evolution of collisional mountain systems —specifically, the ancient Appalachian-Caledonian system. In the first paper, 40Ar/39Ar thermochronological data are used to constrain the timing of exhumation of the Scandian orogenic wedge of northern Scotland. Muscovite and amphibole samples yield dates of ca. 420-411 Ma, consistent with cooling after peak orogenesis. During this cooling phase, dates from both systems in individual thrust sheets show an increase in cooling rate in the later stage of exhumation; in the orogenic core, the cooling rate …


Deformation Of Wall Rocks And Overburden Sequences Proximal To Salt Diapirs In Salt Valley, Utah: Implications For Predicting Subseismic Damage In Salt Tectonic Systems, William Swanger Jan 2022

Deformation Of Wall Rocks And Overburden Sequences Proximal To Salt Diapirs In Salt Valley, Utah: Implications For Predicting Subseismic Damage In Salt Tectonic Systems, William Swanger

Theses and Dissertations--Earth and Environmental Sciences

Although deformation related to salt tectonics is generally considered to be an ancillary field of structural geology, owing to its relatively limited occurrence in the geologic record, the preponderance of salt-involved systems in multiple hydrocarbon-rich basins around the world (e.g., Gulf of Mexico, Atlantic passive margins, Iran, etc.) creates a necessity for understanding salt-related deformation. Traditionally, salt was considered to be relatively weak and thus was mostly unable to drive deformation of adjacent wall rocks and cover sequences. However, a number of recent numerical modeling studies have shown that mobilized and pressurized salt may have the ability to actively pierce …


Viscous Anisotropy Of Wet Olivine Aggregates, Megan Ryan Jan 2022

Viscous Anisotropy Of Wet Olivine Aggregates, Megan Ryan

Williams Honors College, Honors Research Projects

I will deform natural olivine aggregates (Anita Bay dunite) cores in various orientations relative to a natural mineral alignment in the rock under both dry and wet conditions. Different orientations in regards to this mineral alignment will produce deformation on different slip systems. Stress measurements will be taken during the deformation of the samples in order to characterize any changes in viscous anisotropy observed due to the changes in slip system. Anita Bay dunite is a proxy for the main mineral found in the mantle wedge of subduction zones. Therefore, understanding the transformation of viscosity and slip systems in this …


Regional Correlation And Depositional History Using Well Log And Core Data Of The Geneseo-Burket From The Poseidon 8m Well, Westmoreland County Pa, Usa, Spencer Leonard Williams Jr. Jan 2022

Regional Correlation And Depositional History Using Well Log And Core Data Of The Geneseo-Burket From The Poseidon 8m Well, Westmoreland County Pa, Usa, Spencer Leonard Williams Jr.

Graduate Theses, Dissertations, and Problem Reports

Abstract

Regional Correlation and Depositional History using Well Log and Core Data of the Geneseo-Burket from the Poseidon 8M Well, Westmoreland County PA, USA



Spencer Williams

Natural gas producers have invested billions of dollars in Pennsylvania and West Virginia to establish significant gas production from the Devonian Marcellus Shale and the deeper Ordovician Utica-Point Pleasant interval. In addition, commercial gas production has been reported from several other Devonian shale units in the Appalachian region, including the Rhinestreet, Levanna, and Geneseo-Burket. The Marcellus Shale is the largest natural gas play in the United States. The Marcellus is located directly under the …


Structural And Petrologic Insights Into The Emplacement Of Effusive Silicic Lavas: Inyo Domes, California, Shelby L. Isom Jan 2022

Structural And Petrologic Insights Into The Emplacement Of Effusive Silicic Lavas: Inyo Domes, California, Shelby L. Isom

Graduate Theses, Dissertations, and Problem Reports

The Long Valley volcanic region, eastern California, USA is most famous for the caldera-forming eruption which produced the Bishop Tuff ~760,000 years ago. Over the last 3,000 years volcanism has been focused in the western margin of the region through punctuated eruptions of silicic lavas and domes. Three simultaneous effusive silicic eruptions, ~600 years ago, generated three lava domes: Obsidian Dome; Glass Creek Dome; and Deadman Dome which erupted onto vastly different topographies. These domes are exceptionally unique as they erupted variable amounts of two textural and chemical endmember lavas (crystal-rich and crystal-poor) that intimately mixed. The overarching goal of …


U-Pb Apatite Chronometry Of Intrusions In An Accretionary Metamorphic Belt In Western Idaho, Usa, Colleen Grace Rankin Jan 2022

U-Pb Apatite Chronometry Of Intrusions In An Accretionary Metamorphic Belt In Western Idaho, Usa, Colleen Grace Rankin

MSU Graduate Theses

The Salmon River suture zone in west-central Idaho, USA records the tectonic processes where island arcs, similar to modern-day Japan, were accreted to the North American continent in the Jurassic and Cretaceous periods (160-90 million years ago). This suture zone contains metamorphic rocks that were buried deep within the crust at depths of 20 kilometers or more and have subsequently been brought to the surface. The exhuming processes responsible for the metamorphic rocks in the Salmon River suture zone remains unclear. Two competing hypotheses have been proposed to explain the transport of the rocks from the Salmon River suture zone …


Geology Of The Porter Gap 7.5–Minute Quadrangle, Alabama, And Stretched Pebble Analysis Within The Western Blue Ridge Of The Southern Appalachians, Tessa Mills Jan 2022

Geology Of The Porter Gap 7.5–Minute Quadrangle, Alabama, And Stretched Pebble Analysis Within The Western Blue Ridge Of The Southern Appalachians, Tessa Mills

MSU Graduate Theses

The Porter Gap 7.5–minute quadrangle in eastern Alabama contains portions of the undifferentiated sedimentary Knox Group of the Valley and Ridge province, the metamorphic Talladega Group of the western Blue Ridge, and the metamorphic Ashland Supergroup of the eastern Blue Ridge. Three major faults separate the rock units, including the Talladega-Cartersville fault, the Hillabee thrust fault, and the Hollins Line fault. Deformation and metamorphism of rocks within the Talladega Group occurred during the middle to late Mississippian (~334–320 Ma) recorded by stretched pebbles within the Cheaha Quartzite member of the Lay Dam Formation. Stretched pebbles within the Cheaha Quartzite have …


Effect Of Pre-Existing Fault Orientation On Strain Localization In A Foliated Granitic Gneiss, Geoffrey Hilliard Jan 2022

Effect Of Pre-Existing Fault Orientation On Strain Localization In A Foliated Granitic Gneiss, Geoffrey Hilliard

Williams Honors College, Honors Research Projects

The effect of fault orientation relative to the applied stress on reactivation of pre-existing brittle faults instead of forming new faults is well-explained by Mohr-Coulomb theory. However, Mohr-Coulomb theory does not explain the effect of orientation on reactivation of faults with a ductile rheology and no work has been performed to assess the effect of orientation of a pre-existing ductile fault on fault strength. In order to determine how rock strength and localization of strain into a ductile fault is affected when the orientation of the pre-existing fault (artificial fault) is changed, experiments were performed on pre-faulted cores of a …


Geology Of The Jacksonville 7.5 Minute Quadrangle And U–Pb And (U–Th)/He Reveal Sediment Routing And Uplift In The Southern Appalachian Valley And Ridge Province, Derek L. Spurgeon Jan 2022

Geology Of The Jacksonville 7.5 Minute Quadrangle And U–Pb And (U–Th)/He Reveal Sediment Routing And Uplift In The Southern Appalachian Valley And Ridge Province, Derek L. Spurgeon

MSU Graduate Theses

The southern Appalachian Mountains have experienced multiple deformation events having undergone two full Wilson cycles. The foreland Valley and Ridge province is composed of sedimentary Paleozoic rock that range in age from earliest Cambrian to Middle Pennsylvanian. This sedimentary basin was intensely folded and faulted during the collision of Gondwana during the Middle to Late Carboniferous Period. From previous geologic structural mapping that has taken place, some large-scale structures in the Valley and Ridge Province seem to be out of sequence. To better understand the relationships in these structures, geologic mapping in high detail at the 1:24,000 scale coupled with …


Dynamic Relationship Study Between The Observed Seismicity And Spatiotemporal Pattern Of Lineament Changes In Palghar, North Maharashtra (India), Biswajit Nath, Ramesh P. Singh, Vineet K. Gahalaut, Ajay P. Singh Dec 2021

Dynamic Relationship Study Between The Observed Seismicity And Spatiotemporal Pattern Of Lineament Changes In Palghar, North Maharashtra (India), Biswajit Nath, Ramesh P. Singh, Vineet K. Gahalaut, Ajay P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The Palghar region (north Maharashtra, India), located in the northwestern part of the stable continental region of India, experienced a low magnitude earthquake swarm, which was initiated in September 2018 and is continuing to date (as of October 2021). From December 2018 to December 2020, ~5000 earthquakes with magnitudes from M1.2 to M3.8 occurred in a small region of 20 × 10 km2. These earthquakes were probably triggered by fluid migration during seasonal rainfall. In this study, we have used multi-temporal Landsat satellite data of the year 2000, 2015, 2018, 2019, and 2020, extracted lineaments, and studied the …


The Relationship Between Seismic Quality Factor And Peak Ground Acceleration, A Case Study: M=4.3, 17.01.2015 Eskişehir Earthquake, Muammer Tün Dec 2021

The Relationship Between Seismic Quality Factor And Peak Ground Acceleration, A Case Study: M=4.3, 17.01.2015 Eskişehir Earthquake, Muammer Tün

Bulletin of the Mineral Research and Exploration

Seismic wave propagation in subsurface media endures from absorption, which can be evaluated by the seismic quality factor Q (Q-factor). Absorption is frequency-dependent. Lower frequencies are absorbed less, while higher frequencies are absorbed more. Therefore, the Q Factor should be determined in the frequency domain. Q-factor is determined by the slope of the natural logarithm of the output-input signals ratio. Surface waves (Rayleigh and Love waves) are particularly important, as they are the more destructive phases of an earthquake. This study was, focused on the Q-factor computation of the surface waves and demonstrated that the determination of the Q-factor is …


Active Tectonics Of Gülpınar-Tuzla Area (Biga Peninsula, Nw Turkey): The Source Of 6 February-24 March 2017 Earthquake Cluster, Ali Koçyi̇ği̇t, Şule Gürboğa Dec 2021

Active Tectonics Of Gülpınar-Tuzla Area (Biga Peninsula, Nw Turkey): The Source Of 6 February-24 March 2017 Earthquake Cluster, Ali Koçyi̇ği̇t, Şule Gürboğa

Bulletin of the Mineral Research and Exploration

The variation in the motion sense of Anatolian platelet in Aegean Sea resulted in a strike-slip tectonic regime and related neotectonic domain, the central to northern Aegean neotectonic province, which also includes both western Marmara Sea and Biga Peninsula. Our study focuses mostly on the Gülpınar-Tuzla earthquake area located at the southwestern tip of Biga Peninsula,which is controlled by the southern major strand of the North Anatolian Fault System (NAFS). The strand consists of two sections, the onshore Biga and offshore Babakale-Skyros sections. Both sections are seismically very active. The Gülpınar-Tuzla earthquake area is composed of the Paleozoic metamorphic rocks, …


Spatial Variations Of Stochastic Noise Properties In Gps Time Series, Xiaoxing He, Michael Simon Bos, Jean-Philippe Montillet, Rui Fernandes, Timothy I. Melbourne, Weiping Jiang, Wudong Li Nov 2021

Spatial Variations Of Stochastic Noise Properties In Gps Time Series, Xiaoxing He, Michael Simon Bos, Jean-Philippe Montillet, Rui Fernandes, Timothy I. Melbourne, Weiping Jiang, Wudong Li

Geological Sciences Faculty Scholarship

The noise in position time series of 568 GPS (Global Position System) stations across North America with an observation span of ten years has been investigated using solutions from two processing centers, namely, the Pacific Northwest Geodetic Array (PANGA) and New Mexico Tech (NMT). It is well known that in the frequency domain, the noise exhibits a power-law behavior with a spectral index of around −1. By fitting various noise models to the observations and selecting the most likely one, we demonstrate that the spectral index in some regions flattens to zero at long periods while in other regions it …


Timescales Of Magma Transport In The Columbia River Flood Basalts, Determined By Paleomagnetic Data, Joseph Biasi, Leif Karlstrom Oct 2021

Timescales Of Magma Transport In The Columbia River Flood Basalts, Determined By Paleomagnetic Data, Joseph Biasi, Leif Karlstrom

Other Staff Materials

Flood basalts represent major events in Earth History, in part because they are linked to large climate perturbations and mass extinctions. However, the durations of individual flood basalt eruptions, which directly impact potential environmental crises, are poorly constrained. Here we use a combination of paleomagnetic data and thermal modeling to create a magnetic geothermometer (MGT) that can constrain the active transport lifetime of magmatic conduits and intrusions. We apply the MGT technique to eight feeder dike segments of the Columbia River basalts (CRB), demonstrating that some dike segments were actively heating host rocks for less than one month, while other …


Tectonic And Geotechnical Review Of Bengal Basin For Seismic Risk Assessment In Bangladesh, Mir Fazlul Karim, Jnana Ranjan Kayal, Daya Shanker, Nazrul I. Khandaker, Arif M. Sikder, M Zillur Rahman, Muhammad Qumrul Hassan Oct 2021

Tectonic And Geotechnical Review Of Bengal Basin For Seismic Risk Assessment In Bangladesh, Mir Fazlul Karim, Jnana Ranjan Kayal, Daya Shanker, Nazrul I. Khandaker, Arif M. Sikder, M Zillur Rahman, Muhammad Qumrul Hassan

Publications and Research

Four major geotectonic provinces of the basin are recognized: 1) the continental slope to the west of the Hinge Zone, 2) the stable shelf, 3) the deep central trough (Sylhet-Hatiya) and 4) the Chittagong-Tripura fold belt to the east. The ~300 km long Dauki Fault demarcates the elevated Shillong Plateau, part of the Indian Shield to the north and the deep basin to the south. The basin experienced three strong to major intraplate earthquakes: a) 1885 Bengal earthquake (rev. Mw 6.8) close to the Hinge Zone, b) 1918 Srimangal earthquake (rev. Mw 7.1) on the Sylhet (trough) fault and c) …