V.A. Viginsky (Russia)
Neotectonics of Black Sea and surroundings
During compiling "Neotectonic Map of Northern Eurasia» (editor-in-chief A.F.Grachev) author built a map of Black Sea vertical amplitudes of neotectonic
moves. The tectonic modes were selected: platform, orogenic and "deep-sea basin" mode. Orogens in a surrounding of
the Black
Sea were
learnt later. Two their types are selected: collisional (the Strandja-massive,
Pontides, Central&Little Caucasus Syntax, Western Crimea) and Cober orogens (Balkan, Eastern
Crimea, Northwest Caucasus). The orogens of last type were
formed above flysch compensation troughs of Cretaceous rear basin island arcs
as a result of isostatic up-floating light flysch stratas. For collisional
orogens twinning of an earth-crust is characteristic. Mechanics of its
uplifting also is an isostatic nature. It’s caused by earth-crust augmented
thicknesses in their limits testify to it. "Deep-sea basin" mode caused by compensational
movements in a result of lateral flows mantle material towards the deficit
areas under circum Black Sea orogens.
Last years the inner structure of Black Sea northeast part sedimentary stratas was
subjected to close learning. The vertical amplitudes of the neotectonic moves
in this area were minimized, however, intensity of deformations were high
enough. The applying of tectonofacial analysis has allowed learning conditions
of forming of stratas caused by extended horizontal tectonic stream of Tuapse
trough Maycop clays aslope of the Black Sea trough. It has given in forming mud volcano,
progressing turbidities during late Miocene-Pliocene, intensive deformation of
stratas and, thereof, - to making favorable conditions for oil-gas bearing.