四川盆地仪陇地区二叠系长兴组生物礁发育特征精细刻画

Description of Reef Development Characteristics of Permian Changxing Formation in Yilong Area, Sichuan Basin, Yilong Area

摘要: 四川盆地仪陇地区长兴组生物礁特征与元坝地区相似，具有“一礁一藏”的特点及广阔的勘探潜力；文中对比了仪陇地区和元坝地区生物礁的生长模式，分析沉积环境、储集空间类型及生物礁的地质特征。在此基础上，利用钻井、测井及地震等资料，进行生物礁模型地震正演，确定生物礁地震相识别模式。并采用古地貌分析确定生物礁发育的有利沉积相带，识别出了长兴组沉积晚期的一次海泛沉积–辅助层，并利用该辅助层对生物礁进行解释，极大得提高了长兴顶的古地貌刻画精度。其后在小礁体识别的基础上，开展了生物礁内幕精细雕刻攻关，形成了以多属性体融合技术下的生物礁内幕精细雕刻技术，更加直观、形象而准确的揭示了台缘带、生物礁群、单礁体分布特征，首次建立了一套针对四川盆地仪陇地区生物礁有效刻画技术，加快了仪陇地区长兴组生物礁的勘探进程，为仪陇地区天然气持续稳产提供资源保障。

Abstract: The reef characteristics of Changxing Formation in Yilong area of Sichuan Basin are similar to those in Yuanba area, with the characteristics of “one bioherm, one reservoir” and broad exploration potential. This paper compares the growth patterns of reefs in Yilong area and Yuanba area, and analyzes the deposition environment, reservoir space types and geological characteristics of reefs. On this basis, using drilling, logging and seismic data, the seismic forward modeling of reef model is carried out, and the identification mode of reef seismic facies is determined. The favorable deposition facies zone of reef development is determined by paleogeomorphology analysis, and the primary flooding sedimentary auxiliary layer of late Changxing formation is identified. The auxiliary layer is used to interpret the reef, which greatly improves the accuracy of paleogeomorphology description of changxingding. Then, on the basis of small reef identification, we carried out the research on the fine carving of reef interior, formed the fine carving technology of reef interior based on multi-attribute body fusion technology, revealed the distribution characteristics of platform margin zone, reef group and single reef more intuitively, vividly and accurately, established a set of effective depiction technology for the first time in Yilong area of Sichuan Basin, and accelerated the development of the instrument The exploration process of Changxing Formation reef in Yilong area provides resource guarantee for the sustainable and stable production of natural gas.