Study On Key Techniques Of Salt Formation Drilling On KS 9 Block Of Tarim Oilfield

Kuqa piedmont KS block is one of most important part of the tarim oil field,and it is he key west-east gas air block because of it rich oil and gas resources,so carries on the effective development of strategic significance is extremely important.But the tectonic burial depth,formation is complicated,the development of salt layer and composite salt,drilling problems are facing a series of problems.For the above conditions,finding out the effect of related factors on drilling process,formulate effective measures,take reasonable method to solve the engineering problem in tarim oilfield is the urgently problem needed to solve.Fource on the drilling problem on KS block of the tarim oil field,the key technology research was carried out of salt formation.Firstly,the sedimentary succession of the sedimentology characteristics,rock salt layer,layer distribution characteristics and brine salinity brine overall characteristics was analyzed,and find out the routing cause of the drilling problem.Then through salt-gypsum layer of drilling hazard analysis,salt paste layer physical and chemical performance analysis,rock salt paste mechanics characteristics and different types of strata on the borehole wall stability study,finding out the method to prevent the borehole wall instability.Then carry out the bottom to the top of the salt and salt formation identification method research,foucs on the engineering difficulties,the measure for sticking horizon was carried out.And finally,after the on-site drilling test,proved that the proposed technical methods is feasibility and right.In this paper,based on the research of the compound block huge thick salt layer,the silent mode,sedimentary sequence,high pressure brine layer development,wellbore stability,geological layer and narrow density window for safe drilling draws the following conclusions:(1)KS block buried deep salt layer,for gypsum lake evaporation sedimentary environment,sedimentary environment belongs to cream salt lake to evaporate into salt mode;(2)high pressure between salt brine as the lens,the reservoir space and the volume is limited,can implement water pressure relief way effective decompression;(3)salt layer CARDS are the key factors influencing the KS block exploration and production;(4)to reduce and drilling fluid density is the key to the safe drilling narrow between the salt density.