This radioactive decay forms the basis of the U-Th-Pb and U-Th-He methods of geochronology, each of which have different geological significance.
The (U-Th)/He and fission-track methods yield concordant estimates for the timing of the onset of extensional faulting in the White Mountains ca. Given the partially overlapping temperature-sensitivity windows, the (U-Th)/He and fission-track thermochronometers are highly complementary and may be used together to reconstruct thermal histories over the temperature window of ∼40–110 °C.This proxy incorporates creation of crystal damage proportional to α-production from U and Th decay, and the elimination of that damage governed by the kinetics of fission-track annealing. The RDAAM predicts an effective He closure temperature of 62°C for a 28 ppm e U apatite of 60 μm radius that experienced a 10°C/Ma monotonic cooling rate; this is 8°C lower than the 70°C effective closure temperature predicted using commonly assumed Durango diffusion kinetics. acknowledges support from the Ann and Gordon Getty Foundation.The RDAAM is a version of the helium trapping model (He TM; Shuster D. Use of the RDAAM is most important for accurate interpretation of (U–Th)/He data for apatite suites that experienced moderate to slow monotonic cooling (1–0.1 °C/Ma), prolonged residence in the helium partial retention zone, or a duration at temperatures appropriate for radiation damage accumulation followed by reheating and partial helium loss. We thank Ray Donelick for supplying many of the apatite fission-track density measurements that are used in the model calibration.A fundamental driving force behind these applications have been technological advances in mass spectrometry and micro-analytical technology, which have led to a steady reduction of sample size while increasing sample throughput at the same time.The technological evolution of the U-Th-He method can be broadly divided into three periods. Smith References: RUTGERS THE STATE UNIVERSITY OF NEW JERSEY - NEW BRUNSWICK, 2008, 195 pages; 3349591 The Transport, Transformation, and Trophic Transfer of Bioactive Metals in an Urban Impacted Buoyant River Plume Instrumentation: Thermo Finnigan Element & Element XR Author: Derek D. Brandon, Raymond A Donelick, Stefan Nicolescu References: American Journal of Science, 2003 June, 303, 489-518 Read Abstract Analyzing Semiconductor Samples With the ELAN DRC II ICP Mass Spectrometer Instrumentation: Author: Arthur F. Wolf, Katsu Kawabata, J-M Collard, Robert Thomas References: Atomic Spectroscopy, 2003 March/April, 24(2), 37-39 Read Abstract Extremely light Li in orogenic eclogites: The role of isotope fractionation during dehydration in subducted oceanic crust Instrumentation: Author: Thomas Zack, Paul B. 2010 Sep-Oct;93(5):1600-8Mn2 regulates myeloma cell adhesion differently than the proadhesive cytokines HGF, IGF-1, and SDF-1 Instrumentation: Thermo Finnigan Element 2 Author: Tobias S. Holt, Vadim Baykov, Tore Syversen, Anders Sundan, References: European Journal of Haematology Volume 81, Issue 6, pages 437-447, December 2008Land-Atmosphere Exchange of Mercury in Temperate Wetlands Instrumentation: Thermo Finnigan Element XR Author: Lora M. Mc Donough References: Earth and Planetary Science Letters, 2003 March, 208(3-4), 279-290 Read Abstract Combined single-grain (U-Th)/He and U/Pb dating of detrital zircons from the Navajo Sandstone, Utah Instrumentation: Author: Jeffrey M. This method is still the most widely used technique today. developed in-situ U-Th-He geochronology by laser ablation.So far, this method has been successfully applied to monazite (Boyce et al., 2006, 2009), zircon (Tripathy et al., 2010; van Soest et al., 2008), and apatite (van Soest et al., 2008). Spectrom., 2007, 22, 1145-1151Caenorhabditis Elegans as a Model to Study Molecular Mechanisms of Methylmercury Toxicity Instrumentation: Thermo Finnigan Element 2 Author: Kirsten Jeanne Helmcke References: Vanderbilt University - Title page for ETD etd-01142010-160908Hormetic effect of methylmercury on Caenorhabditis elegans Instrumentation: Thermo Finnigan Element 2 Author: Kirsten Jeanne Helmcke, Michael Aschner References: Toxicology and Applied Pharmacology Volume 248, Issue 2, 15 October 2010, Pages 156-16Characterization of the effects of methylmercury on Caenorhabditis elegans Instrumentation: Thermo Finnigan Element 2 Author: Kirsten J. Miller III, Michael Aschner References: Toxicology and Applied Pharmacology Volume 240, Issue 2, 15 October 2009, Pages 265-272The painful metal-on-metal hip resurfacing Instrumentation: Perkin Elmer ELAN DRC II Author: The Journal of Bone and Joint Surgury Charing Cross Hospital References: The Journal of Bone and Joint Surgury Charing Cross Hospital Determination of trace metals in seawater by an automated flow injection ion chromatograph pretreatment system with ICPMS Instrumentation: Thermo Element XR Author: Tung-Yuan Hoa, Chia-Te Chiena, Bing-Nan Wanga, Archava Siriraks References: Talanta. Epub 2010 Aug 7The in vitro effects of selenomethionine on methylmercury-induced neurotoxicity Instrumentation: Thermo Finnigan Element 2 Author: Parvinder Kaur, Lars Evje, Michael Aschner, Tore Syversen References: Toxicol In Vitro. Epub 2009 Jan 6Determination of PAHs, PCBs, Minerals, Trace Elements, and Fatty Acids in Rapana thomasiana as an Indication of Pollution Instrumentation: Thermo Finnigan Element 2 Author: Jacek Namiesnik References: J AOAC Int. 761-764 Read Abstract Influence of wildfires on apatite and zircon (U-Th)/He ages Instrumentation: Author: Sara Gran Mitchell and Peter W.