Plate Tectonics and Petroleum Potential of the Laptev Sea Region

SAVOSTIN, L., S. DRACHEV, and D. BATURIN, Laboratory of Regional Geodynamics, LARGE International, Moscow, USSR

About 1600 km of multichannel seismic data with simultaneous gravity and magnetic measurements were collected in the Laptev Sea during 1989. Additionally, a 100 km onshore seismic reflection profile transected the northern termination of the Verrkoyansky Mountains. Data interpretation showed the following.

The tectonic pattern of the Laptev Sea region was formed as a result of two major tectonic phases. The first phase was associated with collisions between the Paleozoic passive margin of Siberia and a number of allochthonous terrains which were previously parts of the North American Paleo-Pacific plate. These tectonic events accompanied the opening of the Canadian basin and ended in the second half of the Early Cretaceous.

The second phase was a result of the opening of the Makarov and the Europeo-Asiatic basins, which caused the rifting processes within the Laptev Sea Shelf.

Seismic onshore data show that the orogenic sequence consists of allochthonous plates which were thrust onto the thick sedimentary cover of the Siberia platform. An underthrusting sedimentary sequence is situated at depths from 3 to 5 km, which present a good possibility to reach by the drill. The geological analogy with Appalachian Mountains United States, permits us to propose a high petroleum potential for this area.

A system of offshore Laptev Sea grabens consisting of a series of alternating tilted and thrusted blocks, along with intrablock pre-drift sediments, are promising as potential hydrocarbon traps. This is akin to structural setting within North Sea oil and gas province.

AAPG Search and Discovery Article #91007© 1991 AAPG International Conference, London, England, September 29-October 2, 1991 (2009)