Search Results - "Mahan, Kevin H."

Confronting Solid‐State Shear Bias: Magmatic Fabric Contribution to Crustal Seismic Anisotropy by Frothingham, Michael G., Mahan, Kevin H., Schulte‐Pelkum, Vera, Goncalves, Philippe, Zucali, Michele

“…Seismic anisotropy is controlled by aligned rock‐forming minerals, which most studies attribute to solid‐state shear with less consideration for magmatic…”
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Fracturing, fluid flow and shear zone development: Relationships between chemical and mechanical processes in Proterozoic mafic dykes from southwestern Montana, USA by Condit, Cailey B., Mahan, Kevin H.

“…Fluids can play an important role in the localization of deformation in the deep crust, yet the specific mechanisms active during the complex interactions…”
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A method for mapping crustal deformation and anisotropy with receiver functions and first results from USArray by Schulte-Pelkum, Vera, Mahan, Kevin H.

“…Lithosphere that has undergone deformation may record this process in the form of fabric such as foliation and lineation from ductile deformation, as well as…”
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Revised maximum depositional age for the Ediacaran Browns Hole Formation; implications for western Laurentia Neoproterozoic stratigraphy by Provow, Ashley W, Newell, Dennis L, Dehler, Carol M, Ault, Alexis K, Yonkee, W. Adolph, Thomson, Stuart N, Mahan, Kevin H

“…Constraining the depositional age of Neoproterozoic stratigraphy in the North American Cordilleran margin informs global connections of major climatic and…”
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Dating Metasomatism: Monazite and Zircon Growth during Amphibolite Facies Albitization by Cailey B. Condit, Kevin H. Mahan, Kelly C. Curtis, Andreas Möller

“…We present coupled textural observations and trace element and geochronological data from metasomatic monazite and zircon, to constrain the timing of…”
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“Inverted” zircon and apatite (U–Th)/He dates from the Front Range, Colorado: High-damage zircon as a low-temperature (<50 °C) thermochronometer by Johnson, Joshua E., Flowers, Rebecca M., Baird, Graham B., Mahan, Kevin H.

“…Zircon (U–Th)/He (ZHe) data were acquired for 23 Proterozoic basement samples from an E–W transect through the Colorado Front Range to evaluate whether…”
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Imaging Faults and Shear Zones Using Receiver Functions by Schulte-Pelkum, Vera, Mahan, Kevin H.

“…The geometry of faults at seismogenic depths and their continuation into the ductile zone is of interest for a number of applications ranging from earthquake…”
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Seismic properties across an amphibolite- to greenschist-facies strain gradient (Neves area, eastern Alps, Italy): New considerations for shear zone imaging by Leydier, Thomas, Goncalves, Philippe, Albaric, Julie, Leclère, Henri, Mahan, Kevin H., Faulkner, Daniel

“…Detecting the presence and geometry of crustal shear zones by geophysical methods relies on our understanding of the intrinsic parameters controlling the…”
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The distribution and composition of high‐velocity lower crust across the continental U.S.: Comparison of seismic and xenolith data and implications for lithospheric dynamics and history by Schulte‐Pelkum, Vera, Mahan, Kevin H., Shen, Weisen, Stachnik, Josh C.

“…The composition of the continental lower crust is not well known. High seismic wave speeds may indicate mafic or garnet‐bearing material, with implications for…”
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From Crystals to Crustal‐Scale Seismic Anisotropy: Bridging the Gap Between Rocks and Seismic Studies With Digital Geologic Map Data in Colorado by Frothingham, Michael G., Mahan, Kevin H., Schulte‐Pelkum, Vera, Caine, Jonathan Saul, Vollmer, Frederick W.

“…Deep continental crustal structures are enigmatic due to lack of direct exposures and limited tools to investigate them remotely. Seismic waves can sample…”
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Lithospheric density models reveal evidence for Cenozoic uplift of the Colorado Plateau and Great Plains by lower-crustal hydration by Levandowski, Will, Jones, Craig H, Butcher, Lesley A, Mahan, Kevin H

“…Subduction at plate boundaries can have thermal, chemical, and physical impacts on broad regions of the continental interior, but these interactions are not as…”
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Quartz shielding of sub-10μm zircons from radiation damage-enhanced Pb loss: An example from a metamorphosed mafic dike, northwestern Wyoming craton by Ault, Alexis K., Flowers, Rebecca M., Mahan, Kevin H.

“…The coupling of two new approaches enabled acquisition of in situ U–Pb data from zircons as small as 5μm in a metamorphosed mafic dike from the Northern…”
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Virtual mapping and analytical data integration: a teaching module using Precambrian crystalline basement in Colorado's Front Range (USA) by Mahan, Kevin H., Frothingham, Michael G., Alexander, Ellen

“…The COVID-19 pandemic hindered the ability to conduct field geology courses in a hands-on and boots-on traditional manner. In response, we designed a…”
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An Exhumation History of Continents over Billion-Year Time Scales by Blackburn, Terrence J., Bowring, Samuel A., Perron, Taylor, Mahan, Kevin H., Dudas, Francis O., Barnhart, Katherine R.

“…The continental lithosphere contains the oldest and most stable structures on Earth, where fragments of ancient material have eluded destruction by tectonic…”
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Stabilization and reactivation of cratonic lithosphere from the lower crustal record in the western Canadian shield by Flowers, Rebecca M., Bowring, Samuel A., Mahan, Kevin H., Williams, Michael L., Williams, Ian S.

“…New U–Pb geochronology for an extensive exposure of high-pressure granulites in the East Lake Athabasca region of the western Canadian shield is consistent…”
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Rheological evolution of a pseudotachylyte-bearing deep crustal shear zone in the western Canadian shield by Orlandini, Omero F., Mahan, Kevin H.

“…Crustal-scale continental strike-slip fault systems are typically thought to be thermally segregated into an upper seismogenic expression and a lower zone of…”
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Monazite as a monitor of shear strain in orogenic crust by Dumond, Gregory, Mahan, Kevin H., Goncalves, Philippe, Williams, Michael L., Jercinovic, Michael J.

“…The Ramsay-Graham heterogeneous simple shear zone model revolutionized our understanding of finite strain variation in orogenic belts. Many deeply exhumed…”
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Neoarchean arc magmatism and subsequent collisional orogenesis along the eastern Rae domain, western Churchill Province: Implications for the early growth of Laurentia by Regan, S.P., Williams, M.L., Mahan, K.H., Dumond, G., Jercinovic, M.J., Orlandini, O.F.

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Exhumation of exposed deep continental crust, western Canadian Shield: Integrating structural analysis, petrology, and in situ geochronology by Mahan, Kevin H

“…High-pressure granulite terranes are important sources of information for understanding deep-crustal architecture and processes related to the evolution and…”
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Zirconium in rutile speedometry: New constraints on lower crustal cooling rates and residence temperatures by Blackburn, Terrence, Shimizu, Nobumichi, Bowring, Samuel A., Schoene, Blair, Mahan, Kevin H.

“…The incorporation of zirconium into the mineral rutile (TiO2) has been both empirically and experimentally calibrated as a measure of rutile crystallization…”
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