Characteristics of the Overpressure Resulted from Hydrocarbon Generation

Abstract:

Overpressure is often encountered in the Jurassic tight sandstones in the central Junggar Basin. In this studt, a new mechanism of overpressure formation related to gas generation is proposed. Organic-rich mudstones have sonic velocity well-line reserves but their densities continue to increase in the over-compacted mudstone system resulting in the overpressure development during the conversion of the organic matter to oil and gas. The top of the overpressure zone correlates with the depth required for a large quantity of gas generation in which the vitrinite reflectance (Ro) is about 0.7%, showing that the overpressure in organic-rich mudstones is closely associated with gas generation.

• Periodical: Applied Mechanics and Materials (Volumes 295-298)
• Pages: 2707-2710
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.295-298.2707
• Online since: February 2013
• Authors: Hai Yan Hu, Hui Wang
• Keywords: Hydrocarbon Generation, Overpressure, Porosity Loss

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