A Calibration Method for Improving the Accuracy of Seismic Interpretation of Faulted Structures

Abstract

The invention discloses a calibration method for improving the accuracy of seismic interpretation of fault-step structures, which belongs to the technical field of oil field development. Step 1: select fault-step data and perform data value detection; Step 2: draw fault-step profiles; Step 3: pass The geophone performs lithological stratification and substitutes it into the drawn fault-step profile; step 4: calculates the seismic interpretation accuracy generated in the fault step of the same material through proportional simulation; step 5: according to the calculated accuracy according to the ratio, substitutes it into the overall In the step data of , the overall accuracy is obtained according to the simulation accuracy. The present invention measures a part of the steps, and then substitutes them into the whole, and adds the generated fuzzy values ​​twice, thereby ensuring the range of accuracy and reducing the influence of the fuzzy values ​​on the overall range, thereby improving the accuracy of seismic interpretation.

Description

technical field [0001] The invention relates to the technical field of oilfield development, in particular to a calibration method for improving the accuracy of seismic interpretation of stepped structures. Background technique [0002] Fault steps are a series of step-like descending faults due to the development of faults on the slope. When they have a certain scale and influence, they can also be classified as a single oil and gas structural unit to improve the relationship between the formations encountered by each well in the target area. The calibration accuracy of the correspondence between seismic phases is the key to improving the accuracy of seismic-tectonic interpretation. At present, the commonly used calibration of well drilling and seismic phase depends on the seismic time-depth relationship. There are two methods to establish the seismic time-depth relationship. The first method is the time-depth relationship of points instead of planes. Stable and flat geolo...

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Problems solved by technology

Although this relationship formula can be calculated and fitted by complex mathematical formulas close to or relatively close to the actual situation of the seismic velocity field by increasing the powers of t, x, and y in the formula, but for large faults, faults Differences in sediment composition and thickness between the upper and lower plates, or even further transformations such as metamorphism, crystallization, and weathering, lead to sudden changes in the seismic velocity field due to the existence of faults. Use the time-depth relationship between the well-drilled formation and the seismic phase determined by the above two methods to calibrate the corresponding position between the well-drilled formation and the seismic phase. The first method has 80-120 The second method has an error of 10-50 meters near the large fault, which will affect the fine development of oilfields in the future

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