Analysis of Neogene provenance in Zhahaquan area, Qaidam Basin

Abstract

It is generally believed that the provenance of the Neogene sandbar reservoir in the Zhahaquan Oilfield in the western Qaidam Basin is consistent with that of the Paleogene. However, existing studies present different opinions on the provenance during the Paleogene, which makes the provenance of the Neogene unclear and affects the study of sedimentary facies and reservoir configuration in the Zhahaquan area. By using SPSS software, clustering analysis was conducted on the limited heavy mineral data from Neogene in this area.Then, the distribution characteristics of heavy minerals from different samples were studied and compared with the Tiemulik provenance and Qimantag-Dongchaishan provenance.It is considered that the Neogene provenance in the Zhahaquan area originated from Qimantag-Dongchaishan, and there is no evidence of intersection and mixing of the two major provenances. The Qimantag-Dongchaishan provenance can be further divided into two secondary provenances, i.e.one covering only the Zha2 well area, Zha401 well area and Zha7 well area, and the other covering the whole area. There is intersection and mixing of the two secondary provenances. This study clarifies the provenance of Neogene deposits in the Zhahaquan area and provides a significant reference for research on sandbar configuration, especially the migration and superposition of sandbars in this area.

Keywords

• qaidam basin
• zhahaquan area
• neogene
• provenance analysis
• heavy mineral
• cluster analysis