Application of 3D seismic and gravity survey in solid potash exploration in Simao Basin,Southwest China
Potash is a strategic and scarce mineral resource in China.The Simao basin is one of the most realistic areas in China to achieve breakthroughs in solid potash prospecting.However,the complex tectonic conditions of the basin and special physicochemical properties of rock salt restrict ore prospecting.In order to explore effective prospecting methods,3D seismics has been applied to potash prospecting for the first time,gravity and other geo-physical technology have also been used at the same time.The results show that:① 3D seismic data processing should focus on the pressing of low-frequency surface waves;② Instantaneous amplitude,trace integration and Prg*CIP in the 3D seismic attributes have unique advantages in identifying the boundary of salt body more than 2000 m deep,and the prediction results with top buried depth from 1700 to 2800 m and area of 4.28 km2 based on these attributes have been confirmed by drilling;③ The application of seismic survey in exploration of potash in mountainous areas is still in the primary stage,and data acquisition,processing and interpretation still need to ac-cumulate data and experience;④ The basic theory of gravity prospecting of potash is reliable,there are negative anomalies in all areas where the shallow salt bodies occur;⑤ The negative gravity anomalies can also be caused by Quaternary and Neogene geological bodies with similar density to rock salt,stratigraphic morphology change and faults,so must combine with other geophysical technology and geological investigation to judge the ore-bea-ring potential of the negative gravity anomalous areas.3D seismic and gravity are effective geophysical methods in the potash prospecting practice in the Simao basin.Due to the multiple solution of the geophysical data and dif-ference in cost of different geophysical techniques,in the future prospecting practice,while they are used should consider effect,efficiency and cost of the geophysical exploration,and combine with basic geology and deposit geology investigations.
万方数据
维普
