About 200 mafic dykes intruded Mesoproterozoic gneisses and granites of Bornholm,a Danish island situated in the southern Baltic Sea between Sweden,Germany and Poland.Field studies along the northern coast document
From an angle of integrative analysis on historical-dynamic geotectonics, the formation mechanism of the Eastern Asia continental-margin and historical background of the evolution-movement of the crustobody are discus...From an angle of integrative analysis on historical-dynamic geotectonics, the formation mechanism of the Eastern Asia continental-margin and historical background of the evolution-movement of the crustobody are discussed. The pull-breaking-extending and thinning of the continental margin crustobody in the region result in the formation of the continental-margin extensional belt.Finally, the theoretical and practical significance of the study is pointed out.展开更多
There is a belt of metamorphic core complexes in the western margin of the Yangtze craton . The geological setting of the belt is similar to that of the Cordilleran metamorphic core complexes . A typical one in this b...There is a belt of metamorphic core complexes in the western margin of the Yangtze craton . The geological setting of the belt is similar to that of the Cordilleran metamorphic core complexes . A typical one in this belt is the Jianglang metamorphic core complex , which has a configuration consisting of three layers : a core complex consisting of Mesoproterozoic schist sequence . a ductile middle slab consisting of Paleozoic meta- sedimentary -basalt characterized by the development of ' folding layer' and an upper cover consisting of Xikang Group which has suffered both buckling and flattening . A detachment fault developed along the contact boundary between the cover and basement causes the omission of Upper Sinian and Cambrian at the base of cover . A lot of normal ductile shear zones developed in the cover causes the thinning of it . All the features show that the early extension results in the thinning of crust , but the formation of the dome and exposure of basement rocks may be the results of superimposing of the E-W directed contraction and the following southward thrusting during Indosinian to Yanshanian orogeny . Syntectonic plutonism and pervasive thermo - metamor-phism in the cover suggest that the thermal uplift also causes the uplift of the MCC .展开更多
文摘About 200 mafic dykes intruded Mesoproterozoic gneisses and granites of Bornholm,a Danish island situated in the southern Baltic Sea between Sweden,Germany and Poland.Field studies along the northern coast document
文摘From an angle of integrative analysis on historical-dynamic geotectonics, the formation mechanism of the Eastern Asia continental-margin and historical background of the evolution-movement of the crustobody are discussed. The pull-breaking-extending and thinning of the continental margin crustobody in the region result in the formation of the continental-margin extensional belt.Finally, the theoretical and practical significance of the study is pointed out.
基金The study is supported by the key project of science and technology of the Ministry of Geology and Mineral Resources (NO .85-01-005-1 )
文摘There is a belt of metamorphic core complexes in the western margin of the Yangtze craton . The geological setting of the belt is similar to that of the Cordilleran metamorphic core complexes . A typical one in this belt is the Jianglang metamorphic core complex , which has a configuration consisting of three layers : a core complex consisting of Mesoproterozoic schist sequence . a ductile middle slab consisting of Paleozoic meta- sedimentary -basalt characterized by the development of ' folding layer' and an upper cover consisting of Xikang Group which has suffered both buckling and flattening . A detachment fault developed along the contact boundary between the cover and basement causes the omission of Upper Sinian and Cambrian at the base of cover . A lot of normal ductile shear zones developed in the cover causes the thinning of it . All the features show that the early extension results in the thinning of crust , but the formation of the dome and exposure of basement rocks may be the results of superimposing of the E-W directed contraction and the following southward thrusting during Indosinian to Yanshanian orogeny . Syntectonic plutonism and pervasive thermo - metamor-phism in the cover suggest that the thermal uplift also causes the uplift of the MCC .
