Coring technology of the Archean buried-hill fractured strata in Bozhong sag

It was designed to carry out coring operation in the Archean buried hills with oil and gas shows to figure out the lithology, physical property and hydrocarbon bearing property of Archean buried-hill reservoirs in Bozhong sag, so as to provide the substantial data for the reserve declaration of Archean buried hills.In view of the serious fragmentation of weathering crust at the top of the buried hill, the existence of the medium-hardness thick granite formation in the development section of inner reservoir space and the high degree of formation compaction, high-strength coring tool was designed and applied, and the coring parameters were optimally designed.Core recovery guaranteeing measures were developed by means of procedure design.When this technology was applied to the coring of 2 wells in Bozhong sag by 4 times, the average recovery was up to 97%.In conclusion, this technology can be popularized and applied to the coring operation in buried-hill broken competent strata.