The nature of the pre-Cretaceous “Tanlu fault zone” viewed in the light of basin-range coupling evolution on its both sides

The Tanlu fault zone is regarded as an intracontinental sinistral strike-slip fault. The predecessor of the fault zone was three important pre-Cretaceous boundary faults, the Paleo-Tanlu fault, Liao-Bo fault and Dunhua-Mishan fault; therefore the ranges and basins on its both sides belonged to different orogenic and basin-making dynamic systems. To the west of the fault zone, the Qinling-Dabie orogen between the Yangtze and the North China craton was an Indosinian collisional one, and the Hinggan-Mongolia (for short, Hing-Meng) orogen was a Hercynian Turkic-type (accretional arc-type) one. Both became intracontinental orogens during the Yanshanian movement. To the east of the fault zone, the Sulu orogen was a Yanshanides formed by collision between the Su-Wan block and Jiao-Liao craton; the Yanji-Chongjin orogen was an Indosinides formed by collision between the Jiao-Liao craton and Khanka block; and farther northwards, there occurred an oblique convergence-shear orogen (interplate orogen) resulting from amalgamation of a group of allochthonous terranes on the Siberian subcontinent along the Dunhua-Mishan fault. Based on what are mentioned above, three generations (Late Paleozoic-Triassic, Jurassic and Cretaceous) of basins have been distinguished and the evolution of the orogeny-coupled molasse basins and volcanic basins on both sides of the Tanlu fault zone have been analyzed. The comparative study confirms that the basins on both sides of the pre-Cretaceous Tanlu fault zone have their respective unique evolutional histories, rather than belonged to the same basin displaced sinistrally by the Tanlu fault zone. The study of the Paleozoic-Triassic epicontinental sediments on both sides of the fault further demonstrates that the Yangtze and North China cratons and Burean-Jiamusi block to the west of the fault zone had once been independent of the Su-Wan block, Jiao-Liao craton and Khanka block to the east. With the closure of part of the Neo-Tethyan oceanic basins in the Early Cretaceous, the embryonic form of the Asian continent appeared. The above-mentioned three boundary faults linked up each other and became an intracontinental sinistral strike-slip fault (the Tanlu fault zone), and then the regional tectonic evolution on both sides of the fault zone tended to be uniform.