RELATION OF DEEP-SEATED AND NEAR-SURFACE STRUCTURES IN THE SOUTHERN PART OF THE YAKUTIAN KIMBERLITE PROVINCE ACCORDING TO SEISMIC DATA

As a result of areal deep sesimic studies in the Earth's crust and upp er mantle, some contrasting anomalies were recognized and mapped to fo rm a complex deep-seated structure. In this paper the main attention i s paid to the results of the study of the ratio of topography features : main seismic boundaries of the Earth's crust and sedimentary cover. Low-amplitude platform structures of the sedimentary cover are reliabl y correlated with more contrasting anomalies of the topography of the seismic top of the lower crust and Moho discontinuity. By means of pal eostructural analysis of the sedimentary covet this relationship permi ts the time of activizing or origin of deep-sealed structures to be es timated at Middle Paleozoic-Mesozoic. A material indicator of this act ivity is nearly coeval manifestations of kimberlite magmatism. Linear character of deep-seated and corresponding near-surface structures is evidence of a tectonic nature of this activity. It could be caused by compressional stresses, at which the horizontal tectonic flow of the l ower crust matter led to considerable variations in the crust's thickn ess, rather expressed poor in the near-surface structures. Hence, bein g nearly coeval with kimberlite megmatism, the structures of the recog nized type may govern regularities of its manifestations near the day surface.