Different Reef Carbonate Diagenesis and Its Influential Factors, Northern South China Sea
南海北部生物礁碳酸盐岩成岩作用差异及其影响因素研究

Because of its favorable physical properties, reef reservoir is inclined to form big oil\|gas reservoir, and it is the hot issue in current researches. There developed a lot of reef in the northern part of South China Sea, and the hydrocarbon potential is great. However, the diagenesis in the eastern and western regions of the northern part of South China Sea is different. The sea level changes were very frequently in Miocene; Reef underwent penecontemporaneous dolomitisation when the sea level dropped in the glacial epoch in the Xisha Islands. However, in the same period, the meteoric cementation in the LH 11-1 oil field formed impermeable barriers, which destroyed the properties of the reef reservoir; The dissolution of anadiagenetic stage along the impermeable barriers made the properties of the porous interval better and become good reservoir. Through comparative analysis, we believe that the difference of diagenesis is caused by the different palaeogeography, palaeotectonics, palaeogeomorphology, paleontology and the oil\|gas input history. It is very important to study the differentiation and influential factors of diagenesis in South China Sea for the palaeoenvironment and exploration and exploitation of oil and gas.