Pdf: http://rogov.zwz.ru/zakharov%20y%20et%20al,2006_isotopes_fareast.pdf

Both the Jurassic climate and Cretaceous climate were very warm in whole, but the Jurassic one apparently was more regular. Cretaceous warming maxima in the northern high latitudes of Far East have been recognized in the early Barremian, early Aptian, late Albian, late Cenomanian, middle Coniacian, early Campanian (isotopic data on the middle Santhonian of the Koryak Upland are abcent); the early Maastrichtian shallow-water cooling was also discovered there. Data obtained agree with both the isotopic data for the northern low-middle latitudes of Far East (Hokkaido and Sakhalin) and Southern Hemisphere, and the paleobotanical evidences from the Koryak Upland and neighbour territories. We believe that great poleward heat transport took place during the most part of Cretaceous time. According new evidence, Late Cretaceous ammonoid shells were most likely secreted mainly in near-bottom conditions where the animals spent most of their life in shallow marine basins; unlike Recent Nautilus and Cretaceous belemnites, Cretaceous ammonoids did not engage in significant short-term vertical migrations in the water column. The highest bioproductivity of Cretaceous high-latitude seas of the Northern hemisphere, as well as other Cretaceous seas of the world fall on Aptian - maxima of 13 C (6.6‰) in the Koryak Upland have been recorded in the upper portion of the Karmalivayam Formation. It was rather high here also in the middle Barremian 13C values in the lower portion of the Karmalivayam Formation reach 4.3‰). Cenomanian-Turonian and Coniacian carbon-isotope anomalies in Far East obtained from inoceramid bivalves seem to be connected mainly with local conditions.