Deep Continental Scientific Drilling Engineering Project in Songliao Basin:progress in Earth Science researcha

The Songke No.2 well (eastern hole)(referred to as Well SK-2),one of the "two wells and four holes"of the Deep Continental Scientific Drilling Engineering Project in the Songliao Basin,is in Anda City, Heilongjiang Province,and was officially completed on May 26,2018.Tlie scientific goals of Well SK-2 cover four aspects:paleoclimate research,resource and energy exploration,primary geological research, and development of deep earth exploration techniques.Since the official commencement of drilling in 2014,the Well SK-2 scientific drilling engineering team has organized and implemented drilling for coring,in situ logging,chemical analysis of core elements,and deep structural exploration around the well.Currently,the following preliminary scientific research progress has been made:4334.81 m in situ core data has been obtained;the centimeter-level high-resolution characterization of the most complete and continuous Cretaceous continental strata ever unearthed has been completed,and the standard profile of continental strata has been initially established;the unconventional natural gas resources and basin-type hot dry rocks in the deep Songliao Basin were found to have good prospects for exploration and development;the climatic evolutionary history of the Cretaceous continental strata was rebuilt for the first time,covering hundreds of thousands to millions of years,and the major events of Cretaceous climate fluctuations have been discovered;all these reveal strong evidence for the subduction and aggregation of paleo-ocean plates,providing a theoretical basis for the re-recognition of the genesis of the Songliao Basin and for deep earth oil and gas exploration.The implementation of the Deep Continental Scientific Drilling Engineering Project in the Songliao Basin is of great significance for exploring the mysteries of the Earth and solving major problems such as those related to the deep energy environment.It is a solid step along the road of "going deep into the Earth".

Progress of Deep Geological Survey Project under the China Geological Survey

Serving as a way to understand the material composition,structure,and dynamic process of the Earth's interior,deep earth exploration is driven by not only mankind's pursuit of natural mysteries but also mankind's basic need to obtain resources and guarantee economic and social development.The first phase of deep earth exploration of China(SinoProbe)was carried out from 2008 to 2016 and tremendous results were achieved.In 2016,the China Geological Survey launched a Deep Geological Survey Project(also referred to as the Project)to continuously explore the deep Earth.Focusing on the national energy resources strategy,the Belt and Road Initiative,and major basic issues of the geological survey,the Project was carried out in Songliao Basin(an important energy base in China)and major geological boundaries and tectonic units including Qilian Mountains-Tianshan Mountains and Qinzhou-Hangzhou juncture belt.The purpose of it is to reveal the process,structure,and forming patterns of the deep ore deposits and petroleum reservoirs,clarify the evolutionary pattern and controlling factors of Mesozoic environmental climate,and discover deep fine structures of key orogens,basins,and mountains by comprehensive geophysical exploration and scientific drilling.Great achievements have been obtained after more than three years of efforts,including a cumulative 1552 km of deep seismic reflection profiles and magnetotelluric profiles,an ultra-deep continental scientific crilling well,a scientific drilling pilot hole,and a magnetotelluric array and a portable broadband seismic array,both of which cover South China.Moreover,significant progress has been made in ultra-deep drilling technology,deep oil and gas discovery in Songliao Basin,and basic geological issues of Qilian Orogen and Qinzhou-Hangzhou juncture belt in South China,greatly accelerating the deep earth exploration in China and further consolidating China's position as a power in deep earth exploration.