Characteristics and Simulation Experimental Study of Generation and Conservation of Deep Carbonate Oils and Gases

Key words: 
• Kgeneration and conservation of deep oil and gas /
• high geopressure /
• late secondary hydrocarbon generation /
• Paleowic crhonate rock /
• TarimRasin

Abstract: The buried depth of oil and gas reservoirs is deep and over half of it is distributed in the depth of >4 500 m in the Tarim Basin. Deep burial causes high geopressure which is beneficial to the conservationof oil and gas reservoirs. The geotemperature at 7 000 m depth in the Tarim Basin is lower than 165below the lower limit of oil-generating temperature, so the conservation depth of oil and gas reservoirs can reach to 7 000 m. The Paleozoic craton basin of the Tarim Basin is characterized by the late secondary hydrocarbongeneration, which is important to the oil and gas reservoirs from the Paleozoic source rocks of the TarimBasin. TheRo> value of oil-genrating high peaks is about 1.2%and the range of the oil-generating win-low can be extended to Ro1.5% The Tieling limestone simulation experiment with high temperature and pressure demonstrated thathigh pressure is beneficial to the conservation of liquid hydrocarbons in carbonate rocks and retards the change of oil to gas. The simulation experiment also indicated that in the deeply buried condition the latesecondary hydrocarbon generation can take place in carbonate rocks because of high temperature andpressure.