ASTENOSPHERIC LINZES IN THE MANTLE OF OIL AND GAS-BEARING REGIONS

Abstract

Experimental and calculated data on the distribution of the velocity of longitudinal seismic waves in the upper horizons of the mantle zones of modern platform activations, geosynclines (including island arcs), continental and oceanic rifts, back-arc basins, continental margins of the Atlantic type are investigated. Some of them are associated with deposits or hydrocarbon manifestations. In all cases, nega/ tive speed anomalies were detected, complicated by local positive ones. Magmatic foci were detected at the same depths. The nature of the disturbances – overheating and partial melting — is confirmed by the data of geoelectrometry, gravimetry, and anomalies of helium isotopy and is consistent with the ideas of the advection-polymorphic hypothesis.

Keywords

• recent activation
• velocity anomalies
• magmatic chambers