Basement Tectonics of China--Continental-Scale Cataclastic Flow: ABSTRACT

Abstract

The basement rock of China deforms by cataclastic flow because at the continental scale (103 km) China maintains the continuity during deformation necessary for flow. Moreover China's constituent basement elements undergo cataclasis because they rearrange by brittle mechanisms in response to compression in the west and extension in the east. Structures, sedimentologic patterns, and earthquakes suggest brittle basement elements at two scales which are distinguished by their mechanical behavior. Larger elements have characteristic dimensions of 102 km and behave as rigid blocks. Smaller brittle elements, 10 km and smaller, occur in zones with flow characteristics at the scale of 102 km. Clay models support the interpretation of flow for Chin as a whole and for ductile zones in particular. The geology of China is used as a guide to prepare clay models and pieces of wood to simulate rigid basement elements. The space between the pieces is filled with clay which simulates zones of ductile basement and both the wood and the clay are covered with a layer of clay which simulates sedimentary rock cover. Wood blocks are moved in a sequence, in directions, and for distances suggested by the tectonic history of China. The resulting location, trend, type, and relative degree End_Page 710------------------------------ of development of clay structures bear remarkable similarities to the structures of China. A few examples are intensely deformed clay analogous to the central China foldbelt, undeformed clay analogous to the Tarim, Ala Shan, Ordos, and other stable areas, and intensely deformed and elevated clay analogous to the upthrusts surrounding the stable areas of China. End_of_Article - Last_Page 711------------