摘要
Abstract
The Cenozoic volcanic rocks are the main hydrocarbon-bearing layers in Wichian Buri Sub-basin of Phetchabun Basin in Thailand. However, the difficulties of lithology identification and uncertainty of lithofacies distribution have seriously restricted further exploration and development of hydrocarbon, due to various rock types related to the complex eruption environments and frequent eruption stages. In this paper, based on the data of cores, rock slice, logging and seismic, the characteristics of volcanic rocks in the study area were studied, and a set of methods for identifying volcanic rocks was established. Meanwhile, the volcanic eruption periods and lithofacies distribution were predicted. The research results show that: (1) weakly alkalic basalts are the main type in the multi-type volcanic rocks, ranging from basic to acid volcanic rocks and lava to pyroclastic in the study area; (2) GR, DEN and Pe well loggings are sensitive to the variation of volcanic rock composition, and FMI can provide information of textures and structures of volcanic rocks, so the combination of the two methods can effectively identify lithology of volcanic rocks; (3) Cenozoic volcanic rocks are the results of three-stage volcanic eruption, and several volcanic lithofacies, such as volcanic vent facies, effusive facies, explosive facies and volcanogenic sedimentary facies, and their distribution was identified and predicted. The conclusions in this paper can provide an effective method for lithology identification of Cenozoic volcanic rocks in study area, and make clear of its lithofacies distribution, which have a certain significance for further exploration and development of hydrocarbon in this area.关键词
火山岩/岩性识别/岩相/Phetchabun盆地/Wichian Buri次盆Key words
volcanic rocks/lithology identification/lithofacies/Phetchabun Basin/Wichian Buri Sub-basin分类
天文与地球科学
