关键词: 呼图壁储气库, 时变微重力, 介质密度, 注采压力

Abstract: In this paper, the 7 phase flow gravity data of Hutubi underground gas storage were used and classical adjustment overall calculation was adopted to obtain the relative gravity variations at each monitoring point in the study area, which combined with the related gas storage injection-production pressure data to obtain the response relationship image between the temporal and spatial characteristics of the gravity field and the injection-production pressure of the area. Finally, based on the dynamic change data of the gravity field observed on the surface of Hutubi underground gas storage, the CGI algorithm (Compact Gravity Inversion) for spatial distribution of anomalous bodies of underground density change was used to invert the subsurface material density change image of Hutubi gas storage and the morphological and structural distribution characteristics of the storage body. The study showed that according to the different injection-production changes of underground gas storage in different periods, the simulation calculation showed that the optimal depth of underground density change of Hutubi gas storage was about 3500m, and the maximum density change of underground material medium was about ±0.7kg/m-3. The images of density changes in different periods could also clearly reflect the NW-SE trend of the internal structure of the gas storage and the morphological structure distribution of the internal storage tectonics was consistent with the geological structure of Hutubi gas storage.

Key words: Hutubi gas storage, time-varying microgravity, medium density, injection-production pressure