Characteristics of a Superimposed Basin and the Promise of a Buried Petroleum Play

Abstract

The term deeply buried oil and gas reservoir was designated for particular oil and gas reservoirs that have a buried depth deeper than 4,000 m. From a geological point of view, this depth is equivalent to the special depth where liquid hydrocarbon was transformed into gaseous hydrocarbon. In general, geologists consider that, in a basin, the deeply buried oil and gas reservoirs identify a petroleum reservoir in the new strata that is positioned beneath the existing productive oil and gas layers. More than 30 years of worldwide in-depth exploration practices confirm that there are plentiful of oil and gas reservoirs in the deep positions of basins. In-depth petroleum exploration not only is an important method for increasing the production rate for an old oil field, but it is also a valuable exploration domain for increasing the production rate in a new oil field (Gan et al., 1988; Guo et al., 1996). Preliminary estimations show that the reserves of deeply buried oil and gas are equal to 28% of the total oil and gas reserves in China. In China, large scale petroleum basins have the preconditions in a deep position to form oil and gas reservoirs. Several deeply buried oil and gas reservoirs have been discovered. Emphasizing oil and gas exploration in deeply buried strata has extraordinary significance for Chinese petroleum exploration.