Carbonate Debris Characteristics and Its Geological Significance in the  Terrestrial Sandstone of Cretaceous Bashijiqike Group, Tarim Basin

Key words: 
• Tarim Basin /
• Cretaceous /
• Bashijiqike Group /
• carbonate fragment

Abstract: Microscopic characteristics of the reservoir from the start, through a variety of experiments that: Cretaceous Bashijiqike sandstone carbonate debris of Kuqa DepressionTabei uplift in Tarim Basin have five major characteristics of clear distinction with cement : Coarse grain size, generally around than the original porosity, and a good grinding round (individual phenomenon of the late pressure solution), the clear outline and a relatively homogeneous distribution in the sand, nonblock classes; debris in the presence of fossils and more to finegrained powder; cements (iron calcite, dolomite iron) and more attached to the brink of debris while there was increased, there were significant changes in limestone, carbonate debris show orange under cathodeluminescence. Carbonate rock debris distribution near the source have the characteristics of coarsegrained, low content, poor separation, poor grinding park, poor homogeneity, while the other far from the source have the characteristics of much fine particle size, high content, good separation, good grinding park, and good homogeneity, shallowshaped tablets, and buried the characteristics of strong pressure solution. The ancient source of carbonate rock formation, drought, heat, nearly salt for the ancient climate and water environment, near the source of the rapid accumulation of ancient geography is the main cause of carbonate debris. Carbonate rock debris of identification and quantification have the importance of geological significance：its effect was significantly lower than that hole by cement, which can effectively explain the causes of high porosity sandstone with high content carbonate , and define the distribution of sediment source area as an effective evidence.