Print this pageAbstract: Plate-Tectonic Evolution of the Far East
New geologic maps prepared in China showing details of calc-alkalic belts and ophiolite belts are the basis for improved interpretations in the tectonic evolution of the Far East.
Pre-Late Triassic history of small plates:
Widespread geologic exposures south of the Siberian craton provide a unique record of subduction and accretion along margins of more than a dozen small plates during Sinian (late Proterozoic) and Paleozoic times. The north-south agglomeration of these blocks began in the west during the Carboniferous and climaxed in the east by Late Triassic. Most Paleozoic deformation appears related to thermalization above subduction zones; however, deformation related to plate collision is evident between north and south China.
Late Triassic to middle Cretaceous history of peripheral subduction:
A largely agglomerated Asian continent was bordered by subduction zones dipping northward under the southwest and southeast edges, and westward under the east edge; some magmatic arcs superjacent to these zones have commercial tin and tungsten mineral deposits. Hydrocarbon-rich basins developed by major epeirogenic subsidence on western margins of the oldest continental nuclei farthest from the eastern subduction zones. Rates of subsidence and subduction appear correlative; areas of magmatic arcs and volumes of sedimentary basins reflect subduction rates; both reached a maximum in Late Jurassic and Early Cretaceous times.
Late Cretaceous and Cenozoic history of peripheral collision and internal extension:
The fully agglomerated Asian continent underwent plate collisions in the northeast, southeast, and southwest. The continuing convergence of the Indian continental plate is causing much neotectonism (seismicity, uplift, and subsidence) in adjacent southwest Asia, particularly along Paleozoic sutures and in flanking reactivated fold systems. Contemporaneous crustal extension between the Siberian craton and the continental margin from Primorye to Taiwan, most evident since Miocene time, is indicated by scattered intraplate shallow seismicity and hydrocarbon-rich grabens, and by voluminous alkalic-basalt volcanism localized along former plate sutures.
AAPG Search and Discovery Article #90962©1978 AAPG 2nd Circum-Pacific Energy and Minerals Resource Conference, Honolulu, Hawaii