| Depth prediction is an important work in the oilfield production capacity construction at home and abroad, which is crucial to the successful implementation of well position. In recent years, the depth error problem has been widely recognized, but there is still a lack of systematic research on the causes and correction methods. Since the 13th Five-Year Plan, the construction of high-quality production capacity in Bohai Oilfield has become the key to the production of 40 million tons. In-depth study of the deep prediction error under the influence of different factors is of great significance to guide the efficient implementation of new well position. Based on the abundant drilling data, seismic data, formation and sedimentary reservoir knowledge of Bohai oilfield, the depth prediction and error problems are deeply discussed from the aspects of measurement tools, research data and geological understanding. The study concluded that the main factors affecting depth prediction include measuring instruments, geophysical data, methods of stratigraphic comparison, reservoir knowledge degree and so on, Clarify the error of measuring instrument influence often appears in different batches of drilling and have certain rules, The errors affected by the geophysical data are mostly concentrated in a certain area, layer or fault near the oil field, Strformation contrast factors, Related to the method of comparison and the selection of the logo layer, The error of the reservoir knowledge factors is related to the knowledge of the distribution characteristics and internal structure of the underground reservoir, With the deepening of understanding, The depth error of the prediction tends to decrease. The results successfully guided the drilling depth of the rocky sand, the exploration of the adjustment well, and the implementation effect of the adjustment well verified the rationality of the results. The systematic understanding, identification method and correction ideas of depth error can also be used for reference in other similar oil fields at home and abroad. |
