Magnetostratigraphy of the Quebrada La Porcelana Section, Sierra de Ramos, Salta Province, Argentina. Initial age limits on the regional Neogene lithostraatigraphy and uplift of the southern Sierras Subandinas

REYNOLDS J.H.; HERNÁNDEZ R.M.; GALLI C.I. AND IDLEMAN B.D.

Journal of South Americaa Earth Sciences

Elsevier

Lugar: Amsterdam; Año: 2001 vol. 14 p. 681 - 692

The present a magnetostratigraphic investigation of Neogene Oran Group strata at Quebrada La Porcelana. La Porcelana area is located in the southern Sierras Subandinas of northwestern Argentina within the zone of ?normal? subduction. The oldest datable Neogene strata were deposited ~8.1 Ma at the base of the Terciario Subandino. We estimate that the youngest strata are considerably younger than metric converter. The basal age is millons of years younger than lateral correlative units farther to the south in the Transition Zone. These choronostratigraphic results suggest that foreland thrusting was initiated much later in northernmost than it was in the Transition Zone. The data suggest that generation and migration of hydrocarbons from the Los Monos source horizon began at ~4.2 Ma, suggesting that trapping structure were available in the region when migration began.