A Study On Yi-Shu Basin To Improve The Drilling Efficiency

Peripheral Yi-Shu basin is the key block of daqing oilfield exploration.The main purpose of the drilling is to obtain the basin formation data to confirm the reservoir quality,objective layer for paleogene,cretaceous,well finished at the basement.Since the eighty’ s,No.1 drilling company undertaked the drilling task in the region,18 wells had been operated from 1995 to now Although drilling technology level enhances unceasingly,but the whole ability of operating need to be further perfect also.There are several operative problems exist in the basin as following:1)The upper formation caving&shrinking easily,because the lithology sucking make expansion.2)Eocene series,sandstone and glutenite have thick mud cake due to the high permeability and caused more down hole complexity.3)There are serious conflict between hole verticality and drilling speed.4)Existing bit can’t adapt to the formation very well.Result in the less footage of single bit.5)There are coal and broken rock in the coring section,coring drilling is very difficult.The problems above give more risk to the drilling operation in Yi-Shu basin.At the same time,it became the major problem that restricted the exploration and development pace and affect the economic benefits greatly.This paper based on the above aspects are studied,put forward a set of suitable construction supporting scheme for Yi-Shu basin.