Guyana-Suriname Basin, South America: Hot Ultra-Deepwater Exploration Opportunities and Liza Field: Worldwide Largest 2015-2016 Hydrocarbon Discovery

Abstract

Hydrocarbon exploration in ultra-deepwater frontier basins is an expensive and challenging enterprise but with potential for extraordinary commercial rewards. Since 1970's, 22 wells drilled offshore Guyana-Suriname proved noncommercial and the basin remained underexplored. In 2012, USGS ranked Guyana 3rd best basin in South America for ~13Bbbl yet to find conventional hydrocarbons. In 2015-2016, Liza field was a world-class discovery of an estimated 1.4Bbbl worth ~$70 billion at $50bbl Brent crude oil, revitalizing exploration activity in the area. Guyana-Suriname basin formed during the Jurassic-transform opening of the Central Atlantic. The petroleum system was long proven by the Tamberajo field on the Suriname shelf but no penetration existed in deepwater prior to Liza wells discovery. Type II marine source rock of Turonian-age are likely to be present in multiple intervals, but quality, quantity, hydrocarbon migration pathway and charge mechanism is uncertain. Multiple reservoirs lie off the axis of large discharging canyons, and are believed to comprise sand-rich stacked channel belts facies entrenched by regional levees. Trap likely formed by erosional truncation of the up-dip section of channels in association with abrupt lithologic change and sealing hemipelagic shale. Liza field is located ~200km offshore in ~1,700m bathymetry in Stabroek block, which is equivalent to ~1,150 GoM blocks. The largest 3D seismic acquisition program offshore Guyana is ongoing covering Stabrok and nearby Canje blocks. Liza play is Upper Cretaceous clastic slope fan with potential for stacked pay. Multiple play types exist including carbonates and over 20 structures with similar attributes as Liza have been mapped on a regional ~10×10km 2D seismic grid. Liza field is a stratigraphic trap defined on 3D seismic data (amplitude supported?). Wells drilled to ~3,500m depth BML encountered ~100m high-quality oil sands with presumably excellent lateral, top and base seal. The purpose of this study is two folds: a) to aid with understanding of the regional and local geologic setting that lead to the Liza field discovery and, b) to illustrate the business potential for drilling in attractive geologic areas that provide ample running room for future exploration. Even if regional hydrocarbon infrastructure and marketplace could receive a transformational improvement, offshore Guyana-Suriname is hot in business opportunities and a great basin to be exploring.

AAPG Datapages/Search and Discovery Article #90291 ©2017 AAPG Annual Convention and Exhibition, Houston, Texas, April 2-5, 2017