Characteristics of heavy minerals from Upper Devonian Donghe sandstone and Silurian sandstone in western Tazhong area,Tarim Basin,and their geological implications
The distribution of heavy minerals in sediments is affected by such factors as provenance, uplift and erosion, paleo-topographic features, palaeo-climate and palaeo-environment. The analysis of heavy minerals can be applied to the explanation of the sedimentary response to tectonic cycles based on the provenance and sedimentary environment. The heavy minerals of Upper Devonian Donghe sandstones and sandstone of Lower Silurian Kepingtage Formation from six wells in western Tazhong area were studied in this paper. The results show that heavy minerals from Donghe sandstone were mainly derived from the re-sedimentation of basement rocks and granite, and then underwent alteration or mixing of basic volcanic and magmatic-hydrothermal activities, while those from Lower Silurian sandstone were mostly transported from the sediments of underlying carbonate rocks, granite and re-sedimentary rocks, indicating the stability of the sedimentary and tectonic movement characterized by multi-source sediments, with the transportation direction of sediments probably from southeast to northwest.