Vv. Reverdatto et Vs. Sheplev, Geodynamic factors of metamorphism and their modeling: Review and analysisof the problem, GEOL GEOFIZ, 39(12), 1998, pp. 1679-1692
Deep geodynamic (tectonic and magmatic) activity disturbs matter and temper
ature balance established previously in the Earth's crust; this results in
metamorphism of the rocks. Five types of metamorphism can be recognized: co
ntact, in low-pressure high-temperature belts, burial (subsidence), Archean
, and collisional. These types are different in thermodynamic conditions, p
aleogeothermal gradients, and metamorphism duration. They are usually assoc
iated with each other. These associations are not casual and reflect certai
n tectonic regularities in the crust evolution. Magmatic intrusions are con
sidered the most important elements of an additional heat supply into the E
arth's crust. In the absence of attendant magmatism, rock temperatures duri
ng the burial metamorphism in the Phanerozoic usually did not exceed those
typical of prehnite-pumpellyite subfacies/facies, and, rarely, greenschist
facies. The collisional metamorphism caused by the subduction or superimpos
ed load manifested itself at nonestablished thermal equilibrium owing to th
e rapid setting and subsequent rapid exhumation of crustal blacks and erosi
on. At present, determination of P-T-t-trends without invoking supplementar
y information can be used only for approximate evaluation of tectonic situa
tions and elucidation of the types (causes) of metamorphism.