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Showing 1 to 16 of 16 for “"Cosmogenic nuclides"”.
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Surface exposure geochronology using cosmogenic nuclides : applications in Antarctic glacial geology
Cosmogenic 3He, 26A1, and 10Be have been measured in a variety of Antarctic glacial deposits in the McMurdo Sound-Dry Valleys region. The goals of this project were to provide age constraints for Antarctic glacial events, to investigate production mechanisms of 3He, lOBe, and 26 A1 in terrestrial …
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Surface exposure geochronology using cosmogenic nuclides : applications in Antarctic glacial geology
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, and the Woods Hole Oceanographic Institution, 1994.
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Dating of alluvial fans from NW Argentina using cosmogenic nuclides and optically stimulated luminescence technique
… (OSL/IRSL) dating and one depth profile for cosmogenic radionuclide dating (10Be) were collected in the Santa Maria Valley in NW Argentina, where the exceptional preservation of several generations of alluvial fans allow exploring the external forcing conditions that led to repeated cycles of …
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Landscape evolution and preservation of ice over one million years old quantified with cosmogenic nuclides 26Al, 10Be, and 21Ne, Ong Valley, Antarctica
… advances and stagnations of the Argosy Glacier. Cosmogenic exposure age dating of these tills provides ages, ice sublimation rates and regolith erosion rates that support the antiquity of the ice below. </p><p> The oldest ice on Earth has an undisputed age of 800 Kya and is at the bottom of large …
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Cenozoic tectonic and geomorphic evolution of the Red River Region, Yunnan Province, China
… during growth of the southeast plateau margin. Cosmogenic ²⁶A1 and ¹⁰Be basin-wide erosion rate and burial ages indicate a background incision rate of [approximately] 0.05 to 0.10 mm/a, lower than the long-term incision rate minimum of [approximately] 0.26 mm/a. Cosmogenically-determined …
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Beryllium-10 derived erosion rates from the Hangay Mountains, Mongolia: landscape evolution in a periglacially-dominated continental interior
Terrestrial cosmogenic nuclides such as beryllium-10 have recently been used as a way to determine basin-average erosion rates around the world. These erosion rates are useful to geomorphologists investigating landscape evolution. The Hangay Mountains in Mongolia are a prime location to use …
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Setting the Holocene clock using varved lake sediments in Sweden
… changes would have modulated the production of cosmogenic nuclides in combination with solar variability. The “8.2 ka cold event” was recorded as a c. 300-year long period of distinctly colder climate conditions centred at c. 7800 cal. BP in the two varved lake sediment sequences in N Sweden. …
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Antarctic glacial chronology : new constraints from surface exposure dating
… exposure dating, using the concentration of cosmogenic nuclides (3He, 21Ne, and 36Cl) in moraine boulders, combined with mapping of glacial moraines from three key locations, is used to provide new constraints to Antarctic glacial chronology. The results are used to reconstruct past West …
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Fault interaction at different time- and length scales : the North Tehran thrust and Mosha-Fasham fault (Alborz mountains, Iran)
… fluvial and alluvial surfaces using terrestrial cosmogenic nuclides (TCN, 10Be, 26Al, 36Cl) and optically stimulated luminescence (OSL). My investigation focuses on the seismically active Mosha-Fasham fault (MFF) and the seismically virtually inactive North Tehran Thrust (NTT), adjacent to the …
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Pliocene-Pleistocene landscape evolution in south-central Chile : interactions between tectonic, geomorphic, and climatic processes
… fluvial terraces in the Coastal Cordillera with cosmogenic 10Be and 26Al and optically stimulated luminescence, respectively. According to my results, late Pleistocene uplift rates corresponding to 0.88 mm a-1 are faster than surface-uplift rates averaging over the last 5 Ma, which are in the …
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Meteoric 10Be as a Tracer for Subglacial Chemical Weathering in East Antarctica
… the subglacial environment. Meteoric 10Be is a cosmogenic nuclide with a half-life of 1.39×106 years that is incorporated into glacier ice, therefore its abundance in the subglacial environment in Antarctica is meltwater dependent. It is known to adsorb to fine-grained particles in aqueous …
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Metodi di analisi delle deformazioni verticali lungo aree costiere della Sicilia orientale e Calabria meridionale
Le aree della Sicilia orientale e della Calabria meridionale sono inserite all’interno di un complesso sistema geodinamico e per tale motivo sono state soggette a deformazioni verticali nel lungo e breve periodo. L’obiettivo di questa ricerca è quello di analizzare la deformazione tettonica …
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Climate variability and glacial dynamics in the Himalaya
In den Hochgebirgen Asiens bedecken Gletscher eine Fläche von ungefähr 115,000 km² und ergeben damit, neben Grönland und der Antarktis, eine der größten Eisakkumulationen der Erde. Die Sensibilität der Gletscher gegenüber Klimaschwankungen macht sie zu wertvollen paläoklimatischen Archiven in …
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From phantom blocks to denudational noise
… upstream decay—from 110 to 10 mm kyr^-1—of cosmogenic Be-10-derived basin-wide denudation rates across the morphological knickpoint that marks the transition from the Transhimalayan ranges to the Tibetan Plateau. This trend is corroborated by independent bulk petrographic and heavy mineral …
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Terrestrial cosmogenic nuclide dating applied in glacial stratigraphy and transportation studies on a greenfield exploration project in Kaarestunturi, Finnish Lapland
… Glacier Dynamic (GD) mapping and Terrestrial Cosmogenic Nuclide (TCN) dating. The local interpretation is set in a regional glacial history framework that is based on wide scaled GD mapping and existing literature. Kaarestunturi is incorporated in multiple regional glacial studies, but no …
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Intermontane valley fills
Sedimentary valley fills are a widespread characteristic of mountain belts around the world. They transiently store material over time spans ranging from thousands to millions of years and therefore play an important role in modulating the sediment flux from the orogen to the foreland and to …