About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

AAPG Special Volumes

Abstract


AAPG Memoir 117: Petroleum Basins and Hydrocarbon Potential of the Andes of Peru and Bolivia, 2018
Pages 251-269
DOI: 10.1306/13622123M1173531

Chapter 9: Exhumation of a Proximal Foredeep and Associated Wedge-Top Basin Evidenced by Porosity versus Depth Trends: The Upper Cretaceous Vivian Sandstones in Northwestern Marañón and Santiago Basins (Peru)

Oscar Lopez-Gamundi, Cecilia Lopez-Gamundi

Abstract

The quartz-rich sandstones of the Upper Cretaceous Vivian Formation constitute the most important reservoirs in the prolific Marañón foreland basin of northern Peru. The Vivian sandstones are largely fluvial in the northeast and transition to a marine shoreface and open shelf in the west. The formation consists of two sand-rich units (Lower and Upper Vivian) with better reservoir characteristics in the Lower Vivian. Porosity versus depth analysis for the dominantly fluvial Vivian sandstones shows a simple trend of decreasing porosity with depth, with facies-dependent variations for wave-reworked facies. This simple linear trend (correlation coefficient R2 > 0.77) indicates that overburden stress is the dominant factor that determines the porosity reduction. Further west, in the wedge-top Santiago Basin, the Vivian sandstones exhibit anomalously low porosities at relatively shallow depths, a distinct diversion from the regional trend. The depth difference between these low porosities and the porosities of the regional trend was used as a proxy for the uplift that the basin has suffered during the Andean deformation in the latest Miocene. The resulting values (up to approximately 2600 m [8530 ft]) are consistent with uplift estimates derived from other methods and suggest that parts of the foredeep have been partially uplifted.


Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Watermarked PDF Document: $14
Open PDF Document: $24