The Uralian orogeny refers to the long series of linear deformation and mountain building
events that raised the Ural Mountains
, starting in the Late Carboniferous
periods of the Palaeozoic
Era, 323–299 and 299–251 million years ago (Mya) respectively, and ending with the last series of continental collisions in Triassic
to early Jurassic
The region affected by the orogeny, the ''Uralian orogenic belt'' or the ''Uralides'', is usually thought of as the boundary between Europe
. It extends from the Aral Sea
to Novaya Zemlya
, and it includes in addition to the Ural Mountains, the Pay-Khoy Ridge
of northwest Russia and the Mugodzhar Hills
of northwest Kazakhstan
. Its total length is about , of which the Ural Mountains are about .
At the latitude of the Middle-Urals Ring Structure
(''c.'' 56° N, between Perm
) the Ural mountains have a eastward-convex bend. It has been proposed that the Precambrian
Middle-Urals Ring Structure caused a disturbance in the orogeny leading to the formation the bend.
[G. Burba (2003).]
The geologic evolution of the Ural Mountains: A supposed exposure to a giant impact
Microsymposium 38, MS011, 2003
The Uralian orogen (''sensu stricto
'') occurred between three Palaeozoic continents, Baltica
, and Siberia
. In the late Precambrian, the northeast margin of Baltica was deformed in the Timanide
orogenies or the assembly of the Pannotia
supercontinent. The break-up of this supercontinent opened the Palaeo-Uralian Ocean, in which a number of unidentified continental fragments rifted
from Baltica. As Baltica collided with Laurentia to form Laurussia, island arc
s and other microcontinent
s were accreted
to Baltica in the Late Devonian-Early Carboniferous.
In the Ordovician-Silurian, Kazakhstania formed separately when subduction
-driven growth accreted crust to a series of small, late Precambrian microcontinents. In the early Late Carboniferous, Kazakhstania began to collide with Laurussia as the Palaeo-Uralian ocean subducted beneath the margins of the latter.
The northern continuation of the Ural mountains, the Pay-Khoy-Novaya Zemlya foldbelt, is the result of the collision between Laurussia and Siberia in the Early Jurassic.
The southern continuation of the Ural mountains, the southern Tian-Shan
mountains, formed in the late Palaeozoic with the closure of the Turkestanian Ocean, an Ordovician-Carboniferous southern branch of the Palaeo-Uralian Ocean. Tian-Shan remained a stable platform
until the Alpine-Himalayan orogeny in the Pliocene-Quaternary.
External links Late Permian Period map
Category:Orogenies of Europe
Category:Geology of European Russia
Category:Geology of Russia