Deep structure of the Verkhnetovskaya kimberlite pipe in the Arkhangelsk diamondiferous province according to passive seismic and radiological methods

Abstract

AbstractThe exploration of kimberlite pipes is difficult. However, information about their deep structure is necessary for tasks such as prospecting, exploration and development of kimberlite pipes. Therefore, it is necessary to increase the efficiency of deep structure research. In addition, pipes in different territories differ in their properties. The latter requires the study of the peculiarities of the manifestation of pipes in various areas. The Verkhnetovskaya pipe is the only kimberlite object currently known in the Chernoozerskaya area of the Arkhangelsk diamondiferous province. This indicates the need for a comprehensive study of this pipe. The main reason it is difficult to study the pipes of the Arkhangelsk diamondiferous province is the large overburden thickness. In order to increase the efficiency of prospecting, we used a set of methods: microseismic sounding method, passive seismic interferometry, H/V method, gamma spectrometry and emanation mapping. The analysis showed that a new field measurement technique was tested in this research, resulting in more stable data. The main improvement in field measurements is the determination of the optimal accumulation time of microseism when implementing the microseismic sounding method. In addition, the location of the stations in the implementation of passive interferometry made it possible to minimize the influence of the azimuthal distribution of ambient noise sources. The studies made it possible to construct the geophysical image of the investigated pipe and the surrounding medium. As a result, it was shown that the northwestern side has a vertical structure, while according to the drilling data, the side has a uniform slope. In particular, the presence of previously unknown lateral channels was shown. The proposed methodology made it possible to obtain important information with minimal time and technical costs, confirming the applicability of the proposed methodology in the Chernoozerskaya area.