Shrimp dating zircon intimidating fantasy football names

Monazite dating is an important technique in geochronological studies.However, monazite U-Pb dating by SHRIMP is much less popular than zircon in geochronological applications.This paper compares the results of SHRIMP U-Pb dating of monazites and zircons separated from two granite samples, indicating that monazite SHRIMP U-Pb dating at the Beijing SHRIMP Centre is feasible and provides identical results within error.

Shrimp dating zircon

The gneiss is the G3 granitic phase of the Arroio dos Ratos Complex of previous authors, and it now defines a geotectonic environment of juvenile accretion of island arcs in the Paleoproterozoic. Th/U ratios are typically magmatic (about 0.4) in the homogeneous cores of zircons (about 2000 Ma), but are metamorphic (∼0.01) in the zoned euhedral rims (about 590 Ma).

The superposition of deformation events during the Neoproterozoic precludes the precise determination of the age of each event in this investigation, but we suggest that the collisional low-angle shear zones occurred at ca. All the Paleoproterozoic gneisses in the region are part of the Encantadas Complex.

Archean units, such as the Santa Maria Chico granulites, were all deformed in this major event of the Transamazonian Cycle.

The dated gneiss may be correlative with the Epupa Complex north and south of the Kaoko Belt of SW Africa.

The latter date now constrains the age of stromatolite-like structures in cherts associated with the felsic rocks, which probably represent some of the oldest preserved evidence of life on Earth.

The zircon ages also indicate that the NGB correlates well chronologically with the BGB and is one of the oldest volcano-sedimentary successions in the southeastern Kaapvaal Craton.

Geochemical data for the felsic NGB rocks suggest formation by partial melting or crystal fractionation of a mafic source that was contaminated by older crust, possibly in a back-arc environment.

Ages of the Neoproterozoic deformation are younger in the Kaoko Belt of Namibia than in its Brazilian counterpart.

We report SHRIMP zircon ages for felsic volcanic rocks of the early Archaean Nondweni greenstone belt (NGB) located in northern Kwa Zulu-Natal Province, South Africa.

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