Earth Tide, Microseepage and Microbial Geochemical Exploration (MGCE)
Mei, Harry; Hitzman, Daniel; Guo, Dongrun; Mei, Bowen
Like the cause of ocean tides, the universal gravitation of the moon and sun also generates the micro-glutinuous-elastic deformation of the solid Earth, so-called Earth tide. As early as mid-1990s, researchers observed the dynamic change of near-surface hydrocarbon microseepage during oil production and suggested that the earth tide is the most logical mechanism for the migrations of gases and liquids within the crust. As a perpetual force, the Earth tide can greatly influence the microfracture system, induce the cyclical opening and closing of microfracture pathways, allow rapid microseepage of light hydrocarbons and elements to the surface. Earth tide may lay a solid theoretical foundation for the surface geochemical exploration of hydrocarbon and mineral deposits.
In order to make reliable detection and interpretation of hydrocarbon microseepage, Microbial Geochemical Exploration (MGCE) was developed to combine a quantitative biological method with a qualitative geochemical method. In the meantime, the concept of "4G" exploration model was developed, which integrates geology, geophysics, geochemistry and geo-microbiology information, to greatly improve sensitivity, accuracy and reliability of hydrocarbon detection of potential traps.
In the past five years, MGCE and 4G exploration model has been applied in over 30 surveys in China with varying terrains ( deserts, mountains, permafrost, loess plateau, coastal area and deep water) and varying exploration targets ( structural, lithostratigraphic, heavy oil, biogenic gas, tight gas and gas hydrate). The basic principles, methodology, case studies with drilling results of MGCE and 4G exploration model will be illustrated in the presentation.
AAPG Search and Discovery Article #90163©2013AAPG 2013 Annual Convention and Exhibition, Pittsburgh, Pennsylvania, May 19-22, 2013