Free live sex chat with hollywood boys - Age dating fault gouge

Only clay (phyllosilicate) gouge was collected; samples lacking pervasive scaly clay fabric were rejected.

For all localities, undeformed mudstone country rock was also dated, using our methods; some localities were multi-sampled progressively away from the gouge zone.

Subsequent burial diagenesis of the Lewis thrust gouge seems unlikely, because: (1) reactions during faulting exhaust most or all of the reactants (Yan et al., 2001), forming stable illite with an Ar diffusion blocking temperature of 250–300 °C; (2) there is a pronounced difference in mineralogy and age between gouge (more illite, younger) and nearby country rock (protolith); and, (3) uplift and erosion immediately followed final thrusting (see below).2.

For two samples, the age of the detrital component of gouge is younger than the age of deposition of the protolith, which may invalidate the IAA method.

Trapped electrons only have a limited time frame when they are within the intermediate energy level stages.

After a certain time range, or temperature fluctuations, trapped electrons will return to their energy states and recombine with holes.

The trapped electrons form para-magnetic centers and give rise to certain signals that can be detected under an ESR spectrometry.

The amount of trapped electrons corresponds to the magnitude of the ESR signal.Unlike undeformed shales, mica in the detrital component of gouge sometimes has been partially or even fully reset (lost Ar, or gained K) by mechanisms that can include accelerated dissolution-precipitation (Vrolijk and van der Pluijm, 1999; Pevear, 1999), heating, and mechanical deformation.The detrital component in adjacent undeformed country rock gives ages older than deposition.3.Ar dates from fault gouge in the Canadian Rockies based on the Illite Age Analysis (IAA) method of Pevear (1999).Price's Comment (2007) discusses both our methods and conclusions.Electron Spin Resonance Dating, or ESR dating, is a technique used to date newly formed materials, which Radiocarbon dating cannot, like carbonates, tooth enamel, or materials that have been previously heated like igneous rock.

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