Question

Тектоническое строение Восточной сибири

Answer 1

В основании сибирской платформы залегает архейско-протерозойский складчатый кристаллический фундамент, на котором располагается осадочный чехол более позднего периода мощностью 10-12 километров. На севере и юго-западе породы фундамента выступает на поверхность (Анабарский массив, Алданский щит, Прибайкальское поднятие). Общая мощность земной коры – 25-30 километров (в некоторых местах достигает 40-45 километров). Мощность и подвижность ледников в этой части Земли была незначительна, поэтому и такого существенного влияния на рельеф, как в других местах они не оказали. 

Answer 2

Tectonic Structure of Eastern Siberia

Eastern Siberia is characterized by a complex tectonic structure, influenced by various geological processes and events. The region is located in northeastern Asia, covering a vast area of Russia. Here, I will provide a detailed overview of the tectonic structure of Eastern Siberia.

Eastern Siberia is part of the larger Siberian Craton, which is one of the oldest and most stable continental blocks on Earth. The craton consists of ancient rocks that formed during the Archean and Proterozoic eons, dating back billions of years. The Siberian Craton is surrounded by younger orogenic belts, which have been formed by tectonic collisions and other geological processes.

The tectonic structure of Eastern Siberia can be divided into several major components:

1. Siberian Platform: The Siberian Platform is the stable interior part of the Siberian Craton. It consists of ancient rocks, including granite, gneiss, and sedimentary formations. The platform is characterized by a relatively flat topography and low seismic activity.

2. Verkhoyansk-Kolyma Folded System: Located in the northeastern part of Eastern Siberia, the Verkhoyansk-Kolyma Folded System is a major tectonic zone. It is characterized by fold and thrust structures, resulting from the collision between the Siberian Craton and the Pacific Ocean plate. This tectonic zone is associated with the formation of the Verkhoyansk and Chersky mountain ranges.

3. Baikal Rift Zone: The Baikal Rift Zone is a prominent tectonic feature in Eastern Siberia. It is an active rift system that extends along the southern shore of Lake Baikal. The rift zone is characterized by normal faulting and volcanic activity. It is believed to be associated with the ongoing extension and thinning of the Earth's crust in this region.

4. Lena-Vilyui Rift Zone: The Lena-Vilyui Rift Zone is another significant tectonic feature in Eastern Siberia. It is located in the central part of the region and extends from the Lena River to the Vilyui River. The rift zone is characterized by graben structures and normal faulting. It is believed to be associated with the extension and rifting of the Earth's crust in this area.

5. Tunguska Basin: The Tunguska Basin is a large sedimentary basin located in the central part of Eastern Siberia. It is characterized by thick sedimentary deposits, including sandstones, shales, and coal seams. The basin is believed to have formed as a result of tectonic subsidence and sedimentation during the Mesozoic and Cenozoic eras.

These are some of the major components of the tectonic structure of Eastern Siberia. It is important to note that the region has undergone significant tectonic activity throughout its geological history, resulting in the formation of various geological features and landscapes.