南海西北部莺歌海盆地HBJM39-1气田储层岩相划分与微相识别

以HBJM39-1-1、HBJM39-1-2A、HBJM39-1-3和HBJM39-1-4等4口井的取心资料为基础,结合层序地层学解释,深入分析了莺歌海盆地HBJM39-1气田储层的岩相沉积特征。研究表明,HBJM39-1气田储层岩相具有颜色深、粒度细、水动力条件弱、生物扰动强且发育风暴沉积等特点。通过地震地质解释、盆地古地貌以及岩心描述等分析研究证实,HBJM39-1气田储层形成于相对较深的沉积水体环境。莺歌海盆地上新世主要发育滨浅海相沉积,但根据古水体环境、生物遗迹相、岩相以及测井相等资料揭示,上新世莺一段至第四系乐东三段尚发育滨外亚相,不发育前滨及以上亚相沉积。同时,为了进行储层非均质性研究,以"泥"、"砂"截然不同的渗流、渗流屏障作用为主线,亦对滨外亚相等进行了进一步细分和较深入研究。

THE LITHOFACIES AND MICROFACIES OF HBJM39-1 GAS RESERVOIR IN YINGGEHAI BASIN OF NORTHWESTERN SOUTH CHINA SEA

Based on drilling data from the wells of HBJM39-1-1, HBJM39-1-2A, HBJM39-1-3 and HBJM39-1-4, in connection with the seismic sequences, we deeply studied the lithofacies of HBJM39-1 gas reservoir in the Yinggehai Basin. Results show that the lithofacies of the HBJM39-1 gas reservoir is characterized by deep color and fine grained deposits with bioturbation and intercalation of storm deposits, formed under weak hydrodynamic conditions. Palaeogeomorphological reconstruction with seismic and core data indicate that the HBJM39-1 gas reservoir was formed in a relatively deepwater environment. Littoral and shallow marine facies dominate the sequences from the 1st member of Yinggehai Formation of Pliocene up to the 3rd member of the Quaternary Ledong Formation. However, facies analysis based on water chemistry, ichnofacies, lithology and logging facies reveal that there also occurs subtidal subfacies. No foreshore and shoreface deposits have been found so far. We also studied in this paper the permeability of the reservoir based on mud and sand ratio. And offshore marine subfacies are also deeply studied.