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Localization of the processes of rocks eclogitization in shear zones is a reason to assume presence of superpressure in them. However, the thesis about connection of superpressure with ductile shear zones may be discussed.
Known tests of metals show, that plastic shear deformations following for elastic, occur without increase of pressure (they are located in discrete subparallel shear zones in condition of compression and a stretching - strips Luders-Tchernov). Shear zones of area of village Gridino with eclogitized rocks are similar to shear zones in metals and, apparently, were formed in the same way. There are some parallel shear zones with mafic dykes; they have uniform style of deformations, scales and character of eclogitization and structural transformations of dyke rocks. Within the shear zones the dykes rocks have shown the bigger competence than containing gneisses. Also there are no large rigid bodies in the studied shear zones about which pressure will be increased.
Localization of rocks eclogitization within studied shear zones we are inclined to explain as follows. Shear zones and wall rocks were in the same pressure-themperature conditions. However, intensive plastic deformations located in shear zones. It's the reason of various behavior of rocks in shear zone and wall rocks. The rocks in shear zones were undergone eclogitization, while undeformed wall rocks remained in metastable conditions and did not undergone the metamorphic recristallization. It is known, that shear zones are favorable for penetration of the fluid, which is the conventional catalyst of the eclogitization. However the presence in studied shear zones of "dry" (or "almost dry") kinds of eclogites (which sharply differ from paragenetic them amphibole eclogites) allows to assume, that plastic shear deformation was enough to initiate the eclogitization at small amounts of a fluid or even without it.
Thus, the available data lead us to idea that eclogitization of rocks may be caused by the plastic deformation (not by superpressure!).
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