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Showing 1 to 16 of 16 for “"thermochronometry"”.
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Geochemistry, Thermochronometry, Petrogenesis, and Geometry of Igneous Dikes in Central Arkansas: Implications for Mississippi Embayment Evolution
… (major oxide and trace element, Nd isotopes), thermochronometry (U-Th/He), and geometry of 11 igneous dikes from the AAP. These data reveal that dikes are potassic-ultrapotassic and extremely enriched in incompatible elements relevant to OIBs and MORBs. Combined with data from other studies, …
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Rapid Middle to Late Miocene Slip Along the Zanskar Normal Fault, Greater Himalayan Range, NW, India: Constraints from Low-Temperature Thermochronometry
The Zanskar normal fault (ZF) is a NW-striking, moderately NE-dipping, normal fault that bounds the northern flank of the Greater Himalaya Range, NW India. The ZF is the far west continuation of the South Tibetan Detachment System (STDS), a major arc-parallel normal sense shear zone that spans the …
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Exhumation, rift-flank uplift, and the thermal evolution of the Rwenzori Mountains determined by combined (U-Th)/He and U-Pb thermochronometry
Rising over 5 km along the border of Uganda and the Democratic Republic of the Congo, the Rwenzori Mountains represent an extreme example of basement rift-flank uplift in the western branch of the East African Rift, a phenomenon common throughout the East African Rift System and characteristic of …
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The post-breakup evolution of the western Indian high-elevation passive margin
… margin. However, published low temperature thermochronometry suggests downwearing or parallel escarpment retreat as alternative models of margin evolution. Here are present the results of a sediment mass balance study utilising new data for the offshore portion of the Western Indian margin, …
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Testing the Origins of the Blue Ridge Escarpment
… migration. The second approach uses U-Th/He thermochronometry along two scarp-normal transects. Topographic analysis used data extracted from DEMs to compare three zones - the Upland, the Piedmont and the scarp zone itself. Parameters such as relief, drainage density, hypsometry, and slope …
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The development and application of microanalytical (U-Th)/He thermochronology
… that the closure temperature for (U-Th)/He thermochronometry is between 206°C and 286°C, but varies from grain to grain, even within suites of crystals obtained from one rock. This may be due to compositional variations in the host monazite. Typically heterogeneous monazite crystals may have …
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New Insight Into the Thermal-Tectonic History of the Southern Antarctic Peninsula: (U-Th-Sm)/He and Fission-Track Thermochronologic Results From Northwest Palmer Land and Alexander Island
… Antarctic Peninsula through the application of thermochronometry, and presents the first high-resolution thermochronologic dataset for arc rocks of northwest Palmer Land. I present 19 new thermochronologic ages obtained via (U-Th-Sm)/He and fission-track analyses of apatite and zircon from arc …
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Long-term exhumation of landscapes along the Pacific-North American plate boundary as inferred from apatite (U-Th)/He and ArcGIS analyses
… in bordering mountain belts, low-temperature thermochronometry and topographic analyses were applied to each area. In the northern San Gabriel Mountains, apatite (U-Th)/He ages are >10 Ma along narrow crystalline ridges topped by low-slope erosional surfaces located within ~5 km of the San …
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Tectonic-Climate Interactions And Glacial History Within The Chugach And Kenai Mountains, Alaska
… Mountains of Alaska. We utilized low temperature thermochronometry and cosmogenic dating to constrain the spatial and temporal distribution of exhumation and glacial history in order to characterize the net effect of glaciers on an orogen that experiences slow rock uplift. We constrain the spatial …
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Integrating apatite (U-Th)/He and fission track dating for a comprehensive thermochronological analysis: refining the uplift history of the Teton Range
… integrating structural analysis and bedrock thermochronometry. New low-temperature cooling ages are documented in three vertical transects across the Teton Range and at low elevations parallel to the Teton fault. Samples adjacent to the Teton fault are consistently young (~9 Ma) and represent …
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Thermo-tectonic record of hyperextension, structural inversion, and foreland basin evolution of the eastern and central Pyrenees
… rifting and hyperextension using multi-mineral thermochronometry. These chapters integrate zircon, apatite, and rutile U‐Pb ages from the Agly and Saint Barthélémy massifs that provide new constraints to understand the decoupled versus coupled extensional evolution, exhumation timing of the …
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A Thermochronological Investigation of Orogenic Architecture, Kinematics, and Tectonic-Climatic Interactions within the St. Elias Orogen, Alaska
… glacial erosion on orogenesis. Low-temperature thermochronometry and subsidiary structural, earthquake relocation, and offshore seismic reflection data from the St. Elias orogen are the basis for a new architectural model and demonstrate an association between glacial denudation and orogenic …
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From phantom blocks to denudational noise
… (>10^6 yr) estimates from low-temperature thermochronometry, ranging from 100 to 750 mm kyr^-1, points to an order- of-magnitude decay of rates of landscape downwearing towards present. We infer that denudation rates must have been higher in the Quaternary, probably promoted by the …
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Tectonic Exhumation and Climate Driven Erosion in Extensional Mountain Blocks: Two Examples from California, USA
The Pacific-North America plate boundary in central and southern California has a complex tectonic history, and constraints are poor for inception of an extensional fault system linked to the southern San Andreas fault, a major tectonic element of this plate boundary. Furthermore, decades of …
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Evolution of Deformation Along Restraining Bends Based on Case Studies of Different Scale and Complexity
Globally, deformation along obliquely converging plate margins produce a wide variety of complex fault patterns, including crustal pop-ups, fault duplex structures, restraining bends, and flower structures. Depending on the plate velocity, plate obliquity, crustal rheology, length-scale, and …
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THE PACE AND TIMING OF CHANGING LANDSCAPES AS VIEWED THROUGH COSMOGENIC RADIONUCLIDES: SYNTHETIC AND REAL EXAMPLES FROM THE CENTRAL ANDES AND AMAZONIA
… which were confirmed through (U-Th-Sm)/He thermochronometry. Together, the knowledge established in the literature and the paleo-erosion rate record built in this study allowed the comparison of the histories of deformation, erosion, and sediment accumulation. With paleo-erosion rate …