Folded basement of the Yamal peninsula and its constructive bounds. K.S. Ivanov, Yu. V. Erokhin, V. N. Puchkov. V. S. Ponomarev, N.P. Kostrov, V.V. Khiler

Year: 
2021

 The book is devoted to one of the most poorly studied issues of the geology of the West Siberian megabasin - namely, the geology of the basement of the Yamal Peninsula. The peninsula contains huge reserves of hydrocarbon raw materials, and therefore an attempt to generalize all the available information about the geology of its basement is justified and relevant. The book provides information about the nature of the region and the history of the geological and geophysical study of the basement. A brief description of the stratigraphy of the rocks of the folded basement of the peninsula and a detailed mineralogical and petrographic description of the rocks encountered during drilling are given. The southern part of the basement apparently belongs to the Uralides. The northern part of the foundation was almost not exposed by drilling. It has been suggested that the basement here is a continuation of the foundation structures of the Gydan-Yenisei region adjacent to Yamal and may refer to the Baikalids or Timanides. A detailed characterization of the geological structure of the part of the Uralides closest to Yamal is given, using the latest data. In particular, the complex oroclinal structure of the Ural-Pai-Khoi bend of a primary rectilinear island arc due to a two-stage collision of the arc with the Baltica continent in the Early Carboniferous and Early Jurassic is characterized. It is suggested that the ancient Cimmerian structures of Pai-Khoi and Novaya Zemlya were formed as a result of the collision of the passive margin of the northern part of the Baltic continent with the buried island arc of the Uralides, which was a continuation or analogue of the Tagil island arc. The deep subsidence of the basement of the central part of the Kara Basin (up to 13 km) and the increased heat flow in this part of it may be associated with the effect of back-arc extension in the pre-Middle Jurassic u1074 time. The location of Yamal on the elevated eastern shoulder of this anomalous area of ​​super-high heat flow is probably the reason for the high oil and gas potential of the peninsula.