下洋壳由于其巨大的埋深而取样困难，使得人们对栖息于此的深部生物圈的认识几乎处于空白状态。IODP360航次从西南印度洋洋脊的Atlantis Bank钻取了宝贵的下洋壳岩石样品，为下洋壳深部生物圈的研究提供了绝佳的机会。基于这些样品，本项目将揭示Atlantis Bank下洋壳栖息生物群系的生物量、组成类群、群落结构及其在垂向的变化规律，结合宏基因组和宏转录组分析，阐述其关键生物功能、代谢途径与生存策略，评估其对下洋壳生物地球化学循环的潜在影响。项目还将通过岩石学的研究，重塑下洋壳的成岩过程、蚀变类型与期次及主要的地球化学过程，结合微生物的研究，阐述Atlantis Bank下洋壳深部生物圈对极端环境条件的响应机制。本研究将会大大的拓展对深部生物圈的认知，并将在丰富深部生物圈的多样性，揭示深部极端环境微生物的生存策略和适应机理，探索生物在地球深部圈层中的空间分布极限等方面产生重要的影响。

Little is known about deep biosphere dwelling in the lower oceanic crust because of the huge depth of lower oceanic crust which is an insuperable barrier to drill and sample them. During the exploration of IODP 360, a series of rock samples were drilled and collected from the lower oceanic crust of Atlantis Bank, Southwest Indian Ridge, providing us a great opportunity to access the deep biosphere within the lower oceanic crust. With these important samples, microbial biomass, community components and structures will be systematically investigated along the depth profile. Research of metagenomics and metatranscriptomics will annotate their (potential) crucial physiological function, metabolic pathway and living strategy. The potential impact of microbiome to the local biogeochemical processes within the lower crust will also be estimated. According to petrological characteristics of rock samples, backgrounds associated with the diagenesis and alterations of these rocks, and geochemical regimes will be constructed. Together with the results of microbial analyses, responses of deep biosphere within the lower oceanic crust to extremal environments will be illustrated. It will significantly contribute to understanding microbial diversity within igneous ocean crust, revealing the ability of these microorganisms adapting to the deep extremal environments, exploring the spatial limitation of microbial distribution within the deep Earth.