As a result of areal deep seismic studies in the Earth's crust and upper mantle, some contrasting anomalies forming a complex deep-seated structure were recognized and mapped. The main attention is paid to the ratio of features of relief in the reference seismic boundaries of the Earth's crust and sedimentary cover. Low-amplitude platform structures of the sedimentary cover are correlated with more contrasting anomalies in the relief of the seismic roof of the lower consolidated crust and Moho discontinuity. This relationship permits estimation of the time of activation or origin of the deep-seated structures as Middle Paleozoic-Mesozoic. An indicator of this activity is nearly coeval manifestations of kimberlite magmatism. Linear character of the deep-seated and corresponding near-surface structures evidences a tectonic nature of this activity. It could be caused by compressional stresses, where the horizontal tectonic flow of the lower crustal matter led to considerable variations in the crust's thickness, expressed to a degree in the near-surface structures, too. Hence, being nearly coeval with kimberlite magmatism, the discussed structures may control the near-surface appearance of this magmatism.
