Journal of Petroleum Geology, Vol.6,
No.2, pp.117-138, 1983
©Copyright 2000 Scientific Press,
Ltd.
A SCIENTIFIC EXPLANATION FOR
THE ORIGIN AND LOCATION OF PETROLEUM ACCUMULATIONS
A. A. Giardini* and Charles E. Melton**
*Dept. of Geology, **Dept. of
Chemistry, University of Georgia, Athens, Ga. 30602, USA.
Abstract
The general concept of petroleum formation
by biogenic mechanisms has been firmly entrenched for a long
time, but there has been no accumulation of convincing
experimental evidence in support of this belief. If, on the other
hand, a juvenile origin is considered, rigorous mathematical and
experimental treatments are possible. This is done here. The
mathematical foundation of the juvenile petroleum model is drawn
from the model that has quantitatively explained the formation of
the atmosphere, the oceans, and surficial carbonaceous matter by
outgassing of the Earth. Experimental data for the abundance of
juvenile precursors of petroleum--H 2 , CO, alcohols and
hydrocarbons-- are obtained from diamond carriers which
crystallized in the upper mantle 3.1 billion years ago. The
correlation that exists world-wide between the distribution of
petroleum accumulations and regions that have experienced
diastrophism is interpreted as demonstrating a direct
relationship between plate tectonics and channels of precursor
outflow from the upper mantle to crustal traps. The conversion of
precursors to petroleum is assigned to maturation processes. The
theoretical coefficient of juvenile petroleum production is
compared with coefficients of petroleum accumulation derived from
published data on 78 giant petroleum accumulations. Agreement is
found in all cases. The various "proofs" of a
biological origin for petroleum are examined and found to be
inconclusive. It is concluded that recognition of a mainly
juvenile origin has been clouded by traces of biologically
derived compounds and fossils that are merely intrinsic to the
sedimentary nature of "source rock" and reservoirs.
Limitations of the juvenile petroleum model and its possible
value for petroleum exploration are discussed.