Z.N. Gnibidenko
O.B. Kuzmina
A.V. Levicheva

Выпуск
Выпуск: 9 , Том: 61 , Год издания: 2020
Сериальное издание : Russian Geology and Geophysics
Страницы: 1028-1035

Аннотация

Magnetostratigraphic data from wells in southern West Siberia that strip the Upper Cretaceous and Cretaceous-Paleogene boundary strata in three areas (three wells in the Omsk Basin, two wells in the Bakchar Iron Basin, and two wells in the southern Kulunda Basin) are used to compile the respective regional magnetic-polarity scale. According to the available biostratigraphic constraints, the deposition spanned the period from Albian to Bartonian. The reported regional polarity scale is based on integrated paleomagnetic and biostratigraphic data from the seven wells and comprises four Upper Cretaceous zones of normal (NK1-2(al-st) and NK2mt) and reverse (RK2km and RK2mt) polarity corresponding to the C34, C33r, C31r, and C30n Chrons of the global magnetic polarity scale and four Paleogene zones of reverse polarity: R1E1zl, R2E1t, R1E2t-i(?), and R1E2l-b, with the first two correlating with the C26r and C25r Chrons. Some of the Upper Cretaceous magnetozones enclose thin intervals (microzones) of the opposite polarity. The regional Cretaceous-Paleogene magnetic polarity scale of southern West Siberia reveals several deposition gaps from 6 to 28 Myr long. The magnetostratigraphic data can be used to determine deposition rates and can make reference for local, regional, and global correlations of geologic events given that polarity reversals are of global extent.