4. MARINE GEOPHYSICS.

The article discusses the Mesozoic-Ceno tectonic and paleo-oceanographic history of the Alpha-Mendeleev Ridge Complex in the Arctic Ocean. The description of glendonites in lower Valanginian and upper Aptian deposits from the Sverdrup Basin in Arctic Canada means that Early Cretaceous seawater temperatures were close to freezing at times. The database from the ridges relevant for scientific drilling is from the pioneering seismic reflection poll and sediment sampling initiative from U.S. drift station T-3. An intensive seismic reflection profiling was conducted across the East Siberian Margin and the adjacent deep abyssal plains.