The Correction Of Horizontal Well Formation Resistivity In The Volcanic Rock

The horizontal well and high angle wells are drilled for exploration and development in the oil and gas field.Because the purpose layer is in deep,has poor physical properties,reservoir space is complex,and the hole in the formation of spatial location is different from vertical wells.There are some differences between the horizontal resistivity logging response and the resistivity logging response of vertical wells.Therefore,this paper aims at the factors which can cause these differences.Determining the main factors and correcting.After the correction,it can get more real well logging information.At first,this paper analyses the geological conditions of Xujiaweizi fault depression zone.At the same time,combined with the data of geological,well logging,mud logging about the horizontal wells and sidetracking horizontal wells which were drilled in this field.And then sets up a corresponding volcanic rock horizontal well model;the model can be divided into three layers of symmetric model and three layers of asymmetric model.Secondly,the finite element numerical simulation technology is used to determine the three-dimensional numerical simulation of volcanic rock resistivity log in the condition of the horizontal well.And to validate this method.Contrasting with the theory chart of Schlumberger,the error is analyzed.Resistivity log average relative error is less than 5%.Thirdly,we can use three-dimensional numerical simulation method to make sure the influence factor of volcanic rock resistivity log under the condition of the horizontal well,And the main influence factors include surrounding rock layer,layer thickness and boundary.The secondary factors include resistivity of the borehole mud,the eccentric of instruments and mud invade.Then to establish the logging response of main factors influencing the correction chart.At last,the correction chart which is established in this paper can be used to chart the actual logging data,and map the horizontal well logging comprehensive interpretation of results.The results show that this chart can be applied to the horizontal resistivity well logging interpretation.The comprehensive interpretation of logging results can accurately provide the relationship between well tracks and strata spatial position.It can improve the accuracy of the horizontal well logging interpretation.