Regional Detrital Zircon Provenance of Exotic Metasandstone Blocks, Eastern Hayfork Terrane, Western Paleozoic and Triassic Belt, Klamath Mountains, California

Abstract

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Understanding a critical basinal link in Cretaceous Cordilleran paleogeography: Detailed provenance of the Hornbrook Formation, Oregon and California

“…Grove et al, 2008). These Precambrian age distributions are not unique (LaMaskin, 2012), and match well with detrital ages found in the Antelope Mountain Quartzite of the eastern Klamath terranes (Wallin et al, 2000), quartzose sedimentary rocks in the Eastern Hayfork terrane of the Klamath Mountains (Scherer et al, 2010), and the Shoo Fly complex and overlap assemblage in the Sierran Foothills belt (Harding et al, 2000;Spurlin et al, 2000). Detrital zircon ages in the Blue Mountains Province and the Black Rock terrane also overlap with the Klamath River Conglomerate cobble ages (Darby et al, 2000), but these regions are not characterized by quartzite units and therefore are not considered likely sources here.…”

Geochemistry of the Great Valley Group: an integrated provenance record

“…Furthermore, the shift in the Precambrian age signature from abundant Grenville-age zircon in Lower Cretaceous strata to a larger proportion of >1800 Ma zircon in Upper Cretaceous strata may reflect derivation of zircon from different meta-sedimentary terranes in the Sierran foothills (Figure 10), such as the Shoo Fly Complex (Harding et al 2000) and overlap sequence (Spurlin et al 2000), rather than from Klamath Mountains sources. This shift to Sierran sources for the Upper Cretaceous GVG is consistent with a change from southto west-directed palaeocurrent indicators and may be related to Late Cretaceous subsidence of the eastern Klamath Mountains and deposition of the middle to Upper Cretaceous Hornbrook Formation on eastern Klamath terranes (Haggart 1986;Nilsen 1993;Surpless and Beverly 2013 Eastern Hayfork Terrane; n = 162 Scherer et al (2010) G r e n v i l l e o r o g e n Y a v a p a i -M a t z a t z a l A n o r o g e n i c g r a n i t e s northwestern Laurentia…”

Zircon U-Pb ages and petrologic evolution of the English Peak granitic pluton: Jurassic crustal growth in northwestern California

“…(3) On the west, the Eastern Hayfork terrane lies in tectonic contact beneath the North Fork terrane along the high-angle Twin Sisters reverse fault. The Eastern Hayfork map unit consists of chert-argillite, broken formation, and micrograywacke mélange hosting various locally derived and exotic blocks (Wright, 1982;Goodge and Renne, 1993;Scherer et al, 2010). The EPC rose and at its present level, stitches the juxtaposed terranes and locally obliterates the Twin Sisters fault.…”