New Zealand Journal of Geology and Geophysics abstracts

---

Provenance and depositional setting of pre-Late Jurassic turbidite complexes in Patagonia, Chile

Víctor Faúndez
Francisco Hervé
Juan Pablo Lacassie

Departamento de Geología
Universidad de Chile
Casilla 13518, Correo 21
Santiago, Chile

Abstract   Metaturbidites of the Eastern Andes Metamorphic Complex, which crop out east of the Mesozoic-Cenozoic Patagonian Batholith, show significant differences in modal and chemical composition with those of the Duque de York Complex which crop out west of the batholith. The modal quartz content of the sandstones of the former is larger and does not spread out of the Transitional Continental field in QFL diagrams as does that of the latter. In the geochemical discrimination diagrams, sandstones from both units plot in distinct fields with little or no overlap. These features strongly suggest different provenance areas and depositional settings. The Eastern Andes Metamorphic Complex was deposited in a basin located on a passive continental margin, and the source area for the clastic rocks had cratonic affinities. By contrast, the rocks of the Duque de York Complex indicate deposition in an active continental margin, which included sedimentary, plutonic, and volcanic rocks, associated with a subduction zone and/or a strike-slip setting. These results suggest that the two units are not coeval, and that they represent deposition before and after the establishment of the active continental margin at the Pacific rim of Gondwanaland during the late Paleozoic or early Mesozoic.

Keywords   sedimentary provenance; tectonic setting; metaturbidites; pre-Late Jurassic; Patagonian Andes; Chile

G01001 Received 23 January 2001; accepted 12 August 2002; published 6 December 2002
New Zealand Journal of Geology & Geophysics, 2002, Vol. 45: 411-425
0028-8306/02/4504-0411 $7.00/0 © The Royal Society of New Zealand 2002 

PDF file of entire paper: Print-quality (1171K) | screen-quality (795K)

---

This year's abstracts | Journal home page | All abstracts | Publishing home page