The Development Of Event Sedimentology And Its Influence On Oil/gas Exploration

Recent major oil and gas exploration discoveries are still concentrated in sedimentary rocks,indicating that the future oil and gas exploration focus is still in sedimentary rocks,while deep water and ultra-deep water become important reserve growth points.Therefore,it is necessary to strengthen the study of deep-water sediments.Deep-water gravity flow and other event sediments are important components of deep-water deposition,so the study of deep-water event sediments is of great significance for oil and gas exploration.With the development of sedimentology,geologists have realized that there are some deposits which are non-mechanical sedimentary differentiation in the sedimentary process,and these deposits are usually formed by some catastrophic geological events.Subsequently,the concept of event deposition is proposed.Event deposition is a sedimentary phenomenon that reflects the sudden,transient,abnormal and spatial ductility of a certain geological event.In geological history,in addition to the large-scale extreme events at the end of the cretaceous period,there are also some events that may occur irregularly and on a limited scale,such as storm events,catastrophic floods,gravity flows,volcanoes,etc.,all of which have sediments accumulation,also known as event sediments.With the rapid development of neo-catastrophism,the study of event sediments has been promoted and event sedimentology has been formed.Event sedimentology mainly studies the sedimentary processes and sediments in the occurrence of global cataclysmic or abrupt events.This paper briefly introduces the development process and research status of event sedimentology,and discusses the relationship between deep-water event sediments(turbidite,tempestite and seismite)and oil/gas,through the ordos basin extension of shahejie group,the bohai bay basin,songliao basin qingshankou formation,windy city group events in junggar basin sedimentary types have analysis concluded that(1)continental lake basin of events sediment in the deep-water sediments is response for tectonic activities.The development of the deep-water sediments,especially the source rocks,in the continental lake basin is controlled by the structure,so it is closely related to the deposition of geological events.(2)turbidites,seismite,tempestites,pyroclastic rocks and tuff in the deep-water sediments of the continental lacustrine basin are the products of sudden geological disasters.Their development is also closely related to tectonic activities,and they can be regarded as favorable reservoirs from their sedimentary characteristics.(3)according to the existing exploration,turbidites,seismite,tempestites and pyroclastic rocks in the deep-water sediments of the continental lake basin can form stratigraphic and lithologic reservoirs,so turbidites,seismite,tempestites and pyroclastic rocks in the deep-water sediments of the continental lake basin may become the direction of oil and gas exploration.