On-sea non-repetitive time-lapse seismic data high-density collection method

Abstract

The invention discloses a method for high-density acquisition of sea non-repetitive towed time-lapse seismic data, comprising the following steps: S1. The seismic acquisition ship takes the first side of the seismic work area as the starting point, and drags a plurality of cables according to one acquisition navigation line Go to the second side of the work area and implement the seismic data acquisition operation; S2. After the seismic acquisition ship completes the seismic data acquisition operation, it enters the seismic work area again from the second side in the opposite direction, and connects multiple cables from the second side of the seismic work area according to another acquisition navigation line. The two sides are dragged to the first side and the seismic data acquisition operation is carried out; S3, steps S1 and S2 are repeated successively, and the acquisition navigation lines are arranged according to the cable spacing of the cables in a rolling manner, so that the distance between two adjacent acquisition navigation lines The distance corresponds to the cable pitch of the cable. The invention realizes the high-density acquisition of seismic data by adopting the way that the acquisition navigation line rolls cable by cable according to the distance between cables, and provides original seismic data meeting the consistency requirement of time-lapse seismic two-phase data for offshore developed oil and gas fields.

Description

technical field [0001] The invention relates to the technical field of time-lapse seismic, in particular to a high-density acquisition method for time-lapse seismic data of non-repetitive towlines on the sea. Background technique [0002] Time-lapse seismic is currently aimed at developed oil and gas fields. Through the combination of specific field observation system design, seismic processing, interpretation, inversion and modeling, etc., it can monitor and analyze the properties of subsurface fluids, as well as fluid saturation and pressure. It is a specialized technology of process change. Its role in analyzing and studying the distribution of remaining oil and gas, optimizing and perfecting the design and deployment of development wells, and finally achieving the purpose of improving oil and gas field recovery has been confirmed by many oil and gas field development experiences at home and abroad. [0003] The main idea of ​​classic time-lapse seismic is to observe the ...

AI Technical Summary

Problems solved by technology

Due to changes in ocean currents, tides, and cable feather angles, there are mostly blank areas in data collection in the first phase of basic collection. In order to ensure that the quality of collected data meets the design requirements, conventional streamer collection generally needs to implement line and shot operations after completing the main collection tasks. The coverage times of underground reflection bins meet the design requirements, which leads to the complicated trajectory of the first-stage basic acquisition seismic ship (such as figure 2 shown)

In addition, changes in ocean currents, tides, and acquisition equipment will lead to huge differences in the feather angle of offshore acquisition cables in different periods

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