Study On Geological Drilling Technology For Horizonatal Well Landing Of Neogene In Bohai Oil Field

For fluvial reservoirs,due to the influence of vertical depth error,lateral heterogeneity,interlayer and physical properties of reservoirs,the landing operation of horizontal wells is more difficult and challenging.Therefore,in order to improve the landing quality and success rate of horizontal wells in Neogene fluvial reservoirs in the Bohai Sea,it is necessary to carry out in-depth research on the matching geological while drilling technology for landing horizontal wells.Aiming at the problems and difficulties in landing of horizontal wells,taking Q oilfield of Bohai Sea large complex fluvial facies oilfield as the main research target,based on in-depth analysis of sedimentary characteristics of fluvial reservoirs,types of sand body superimposition,sedimentary microfacies and logging facies,this paper carries out geological while-drilling technology research on landing of horizontal wells in Neogene reservoirs,and establishes a new drilling technology.The technical process of horizontal well landing can effectively improve the success rate of horizontal well landing.Based on the classification of reservoir characteristics,four typical horizontal well landing models are established under the constraints of physical properties and hydrocarbon-bearing properties,the height of oil-water interface and the distribution pattern of interbeds in reservoirs.The adjacent wells are selected according to the principles of "same genetic unit","similar well spacing" and "similar seismic response characteristics".Accurate prediction of reservoir characteristics at landing point of single well is realized.In addition,in the case of deviation of reservoir depth prediction,the strategy of "stable inclination method" or "rapid inclination increasing method" is adopted,and the loss length and depth of horizontal section corresponding to different well deviation are given through calculation.Three engineering remedial measures and applicability analysis are given in case of landing failure,which complements and improves the content of geological while drilling technology.Through the practical application of 16 horizontal wells in Q oilfield,the success rate of one landing is increased from 80% to 94%,and the practical effect is obvious.