AAPG Memoir 75, Chapter 4:
Pimienta-Tamabra(!)--A Giant Supercharged Petroleum System in the Southern Gulf of Mexico,
Onshore and Offshore Mexico, by Leslie B. Magoon, Travis L. Hudson, and Harry E. Cook,
Pages 83 - 125
from:
AAPG Memoir 75: The Western Gulf of Mexico Basin: Tectonics, Sedimentary
Basins, and Petroleum Systems, Edited by Claudio Bartolini, Richard T. Buffler, and
Abelardo Cant
-Chapa
Copyright 
2001 by The American Association of Petroleum Geologists. All rights
reserved.
Pimienta-Tamabra(!)--A Giant Supercharged Petroleum
System in the Southern Gulf of Mexico, Onshore and Offshore Mexico
Leslie B. Magoon
Applied Geology, Sequim, Washington, U.S.A.
Travis L. Hudson
Instituto Polit
cnico Nacional, Mexico City, Mexico
Harry E. Cook
U.S. Geological Survey, Menlo Park, California, U.S.A.
ABSTRACT
Pimienta-Tamabra(!) is a giant supercharged petroleum system in the southern Gulf of
Mexico with cumulative production and total reserves of 66.3 billion barrels of oil and
103.7 tcf of natural gas, or 83.6 billion barrels of oil equivalent (BOE). The
effectiveness of this system results largely from the widespread distribution of good to
excellent thermally mature, Upper Jurassic source rock underlying numerous stratigraphic
and structural traps that contain excellent carbonate reservoirs. Expulsion of oil and gas
as a supercritical fluid from Upper Jurassic source rock occurred when the thickness of
overburden rock exceeded 5 km. This burial event started in the Eocene, culminated in the
Miocene, and continues to a lesser extent today. The expelled hydrocarbons started
migrating laterally and then upward as a gas-saturated 35-40
API oil with less than 1 wt.% sulfur and a
gas-to-oil ratio (GOR) of 500-1000 ft3/BO. The generation-accumulation
efficiency is about 6%.
