Multi-scale inversion of density structure from gravity anomalies in Tarim Basin

• Published in: Science China. Earth sciences 2011-03, Vol.54 (3), p.399-409
• Main Authors: Hou, ZunZe, Yang, WenCai
• Format: Article
• Language: English
• Subjects: Earth and Environmental Science; Earth Sciences; Geological time; Geophysics; Gravity; Mesozoic; Oil and gas exploration; Oil and gas fields; Paleozoic; Research Paper
• ISSN: 1674-7313; 1869-1897
• DOI: 10.1007/s11430-011-4169-2

Based on the power spectra of gravity anomalies in Tarim Basin, the anomalies can be decomposed to the following three components: a sub-anomaly formed mainly by the basin crystallized basement, a sub-anomaly formed mainly by deep sedimentary layers, and that by shallow sedimentary layers. A special wavelet transform analysis scheme and a density inversion method are designed and applied to the decomposition and inversion of gravity sub-anomalies, which are correlated with regional geology and drilling data. The results indicate that the deep and the shallow sub-anomalies show some relations with ancient fluid active zones. The negative density disturbances inversed from the shallow sub-anomaly are mainly caused by Mesozoic fluid active zones, whereas the negative density disturbances form the deep sub-anomalies are mainly correlated with Paleozoic fluid active zones. As the ancient fluid movement was good for formation of oil/gas fields, the multi-scale inversion methods for locating the ancient fluid movement zones seem to be helpful and valuable to oil/gas exploration.