Page 58 - The Petroleum System From Source to Trap

Magoon, L. B, and W. G. Dow, eds., 1994, The petroleum
system-from source to trap: AAPG Memoir 60.

Chapter 3

Petroleum Systems of the World

Involving Upper Jurassic Source Rocks

H. Douglas Klemme
Bo11dvi/lc, Vcrmo11l, U.S.A.

Abstract

Fourteen "mega" petroleum systems with Upper Jurassic source rocks contain one-fourth of the
world's discovered petroleum. These petroleum systems, their locations in space and time, and their
petroleum plumbing ingredients are reviewed, descrbed, and tabulated. Each system's recovery
efficiency is estimated. Plumbing ingredients are related to the relative magnitude of the petroleum
system's estimated recovery efficency. While the presence of a source rock is a requirement of all
petroleum systems-with source rock abundance and character of considerable influence on
recovery efficiency--other plumbing ingredients are capable of even more influence on the
magnitude of the systrne's recovery efficiency. These other plumbing factors include the quality and
quantity (extent) of reservoir and cap rock, trap evolution and size, and the dynamics and timing of
these factors along with source rock maturation and migration. The character, quality, and quantity
of these petroleum systems' plumbing are related to their plate tectonic location, palelatitudinal
realms, and the structural (tectonostratigraphic) evolution of the basin or province.

INTRODUCTION updip zero edge from either nondeposition or truncation
Fourteen petroleum systems with Upper Jurassic of Upper Jurassic sedimentary rocks along the craton
source rocks contain one-fourth of the world's discov­ margins, (2) positive areas of either nondeposition or
ered petroleum. Eleven other systems with Lower and truncation within the Upper Jurassic depositional trend,
Middle Jurassic source rocks presently have a minor but and (3) an orogenic cut-off zone behind which any
significant amount of discovered petroleum. These Upper Jurassic sedimentary rocks have usually been
petroleum systems are g.eologically reviewed, their destroyed by orogenic metamorphism, intrusion, or
location in space and time is described and mapped on a truncation associated with Phanerozoic terrane accretion.
continental scale, their relative petroleum system The latter is often considered a zone of petroleum
recovery efficiencies are estimated, and the effect their economic basement, although notable exceptions occur
essential elements and processes have on their where the Jurassic source rock is preserved in these
"petroleum plumbing" is outlined. In addition, their zones (see Cook Inlet and Vienna basin).
petroleum dynamics are discussed. Tables 3.1 and 3.2 attempt to organize the petroleum
The information used to identify and map these plumbing ingredients, including source rock, reservoir
Jurassic petroleum systems come from many references, rock, cap (seal rock), trap type, and dynamic characteris­
the more important ones being Bedoes (1973), Beydoun tics, together with an estimate of the recovery efficiency
and Dunnington (1975), Jones (1975), Weeks (1975), for the petroleum systems that involve Upper Jurassic
Nehring (1978, 1981), Kanstler et al. (1984), Carmolt and source rocks. An events chart for each of the 14
St. John (1986), Masters et al. (1987, 1991), Ziegler (1988), petroleum systems outlines the timing of essential
Creaney and Allan (1990), Hubbard et al. (1990), and elements and processes in relation to the timing of the
Zappaterra (1990). system's plumbing dynamics (Figure 3.6). The timing of
In mapping the world's petroleum systems that the initial development of a given trap was found to be
involve Upper Jurassic source rocks, continental maps variable dependent on the type of trap being formed.
(not including Antarctica) with currently accepted Different trap types and different ages and lithologies of
Upper Jurassic paleolatitudes were used as a base. Three reservoir rocks are the departure point for the division of
"cut-off" margins or limits to those Upper Jurassic sedi­ petroleum systems into plays and prospects.
mentary rocks that include source rocks generally Difficulty in naming Upper Jurassic petroleum
considered available for potential petroleum systems are systems by using major source rocks and reservoir rocks
outlined (Figures 3.1-3.5). These cut-offs include (1) the was encountered in the following situations: (1) regions

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