细粒沉积物理模拟研究进展与展望

沉积物理模拟是指在限定条件下对不同沉积环境中的沉积过程进行模拟的实验，其对研究水利工程、环境科学、环境工程、海洋学、沉积学及油气勘探等具有重要意义，但其发展远不能满足生产需求，特别是近年来快速崛起的非常规油气勘探的需求。前人基于无黏性均匀沙的研究，已经建立一系列的泥沙运动理论及方程，在泥沙特性、沉积底形、地貌景观、重力流研究等方面取得了丰硕的成果，但在黏性泥沙（细粒沉积物）方面的研究进展有限。从颗粒特性、侵蚀和沉积作用机制及底形特征、输运机制与沉积模式，以及有机质富集和保存机制等四个方面对细粒沉积物理模拟进行综述，在此基础上结合现代青海湖研究提出一种新的富有机质细粒沉积富集假说，进一步丰富了非常规油气沉积学的含义。细粒沉积物理模拟是泥页岩沉积古环境恢复和岩相分布预测的有效手段，对于非常规油气“甜点”的成因分析和优选有重要意义，多学科交叉和定量化分析是其发展趋势，多类型与多尺度实验是传统模拟实验的必要补充。

Laboratory Experiments on Sedimentation of Fine-grained Sediment:A prospect review

A laboratory experiment on sedimentation is an experiment conducted under highly controlled conditions to simulate the sedimentary processes in a wide variety of sedimentary environments.It is a useful method which has been widely used in many scientific disciplines and sub-disciplines including hydraulics engineering,environmental science,environmental engineering,oceanography,sedimentology,as well as petroleum geology.The recent drastic increase in unconventional oil and gas production requires new insights into fine-grained sediment,such as processes of organic-sediment accumulation.Many equations or theories have been proposed for uncohesive sediments including physical properties of sand/clay particle,sedimentary bedforms,sedimentary landscapes,sediment gravity flows.However,because of their small grain size,and their cohesive properties,cohesive sediments present more of a challenge in the experiment and have been relatively understudied.A review is given of laboratory experiments on sedimentation of fine-grained cohesive sediments,with emphasis on the aspect of physical properties of particles,processes of erosion and deposition,sedimentary bedforms,transport mechanics and facies models,as well as organic matter accumulation and preservation.This article also discusses the organic matter transportation and accumulation in recent Qinghai Lake and proposes a hypothesis of accumulation of organic-rich fine-grained sediments.Laboratory experiments on sedimentation of fine-grained sediment are useful for both paleoenvironment reconstruction and lithofacies prediction,which can be applied to genetic analyses and prediction of sweet spots/areas in unconventional shale plays.A successful research of fine-grained sediment requires the application of methodologies and results of a broad range of scientific disciplines,a combination of physical and computational simulations,and some large-scale and long-term flume experiments.