State Key Laboratory of Petroleum Resources and Prospecting, Beijing Key Laboratory of Petroleum Pollution and Control, Research Centre for Geomicrobial Resources and Application, Institute of Unconventional Oil and Gas Science and Technology, College of Geosciences, China University of Petroleum, Beijing 102249, China.
State Key Laboratory of Petroleum Resources and Prospecting, Beijing Key Laboratory of Petroleum Pollution and Control, Research Centre for Geomicrobial Resources and Application, Institute of Unconventional Oil and Gas Science and Technology, College of Geosciences, China University of Petroleum, Beijing 102249, China.
Sci Total Environ. 2021 Aug 25;784:147009. doi: 10.1016/j.scitotenv.2021.147009. Epub 2021 Apr 10.
Despite the growing body of studies on the various fracturing phrases, the research on the differences between subterranean and surface microorganisms at shale gas drilling sites is still limited. Generally, shale gas development and the production process are divided into drilling and fracturing. The distribution of microbial communities in the latter has been paid some attention, but a deficit remains in terms of our understanding of the microbial community in the former, especially for the phase of drilling flowback and drilling flowback surface. In this study, four drilling flowback fluids (DFFs) (H230-flowback drilling cuttings, H23G-flowback drilling mud, H240-flowback drilling sediment, and H21F-flowback drilling water) from the outlet of subterranean pipeline to the inlet of storage tank were successively collected from H2 shale gas field during its initial drilling in Sichuan, China. Natural mountain water (H10W) used as the injection water of H2 was also sampled. Illumina MiSeq 16S rRNA gene sequencing revealed a total of 8 phyla, 17 classes, 36 orders, 62 families, and 98 genera that were recovered from these samples with uneven distribution. The majority of the obtained sequences belonged to the phyla Proteobacteria (75.36%), Bacteroidetes (10.75%), and Firmicutes (5.64%), with significant differences found in DFFs and injection water. The richness of microorganisms gradually increased with the increasing flowback flowing distance (H230 < H23G < H240 < H21F < H10W), which was employed to reveal a rapid change in microbiota that was evident in samples along the flow path aboveground from a depth of 3548 m. The findings of this study could expand our understanding of the ecological role of microorganisms during the shale gas drilling phase. Furthermore, the study highlights the temporal-spatial trajectory of microbial communities from subterranean environments to the surface in a short period of 30 days.
尽管关于各种压裂阶段的研究越来越多，但对页岩气钻井现场地下和地表微生物差异的研究仍然有限。一般来说，页岩气开发和生产过程分为钻井和压裂。人们对后者的微生物群落分布给予了一定的关注，但对前者微生物群落的了解仍存在不足，特别是在钻井返排阶段和钻井返排地面阶段。在这项研究中，从中国四川 H2 页岩气田首次钻井过程中，从地下管道出口到储罐入口，连续采集了四口钻井返排液（DFF）（H230-钻井返排岩屑、H23G-钻井返排泥浆、H240-钻井返排沉砂和 H21F-钻井返排水），还采集了用作 H2 注水的天然山泉水（H10W）。Illumina MiSeq 16S rRNA 基因测序共从这些样品中恢复了 8 个门、17 个纲、36 个目、62 个科和 98 个属，分布不均。获得的序列主要属于变形菌门（75.36%）、拟杆菌门（10.75%）和厚壁菌门（5.64%），DFF 和注入水中存在显著差异。随着返排距离的增加（H230<H23G<H240<H21F<H10W），微生物的丰富度逐渐增加，这揭示了在 3548 米深的地表以上的流径中，微生物群在样品中迅速变化。本研究的结果可以扩展我们对页岩气钻井阶段微生物生态作用的认识。此外，该研究突出了在短短 30 天内，从地下环境到地表的微生物群落的时空轨迹。
