The paper describes the sedimentary features and biostratigraphy of the transitional Jurassic to Cretaceous deposits in the continental basins of Priamurie formed after the collision between the Siberian and North Chi...The paper describes the sedimentary features and biostratigraphy of the transitional Jurassic to Cretaceous deposits in the continental basins of Priamurie formed after the collision between the Siberian and North China blocks. In Upper Priamurie, the collision occurred in the late Early Jurassic as dated by the emplacement of the post-collisional granites （ 191 Ma）. While in Lower Priamurie and West Priokhotie it could take place in the late Middle Jurassic on the basis of fossil evidence from an aceretionary turbidite complex. This event reflected the environmental change from coastal-marine to alluvial plains, often boggy, where coals aecmnulated. The environinental change is in harmony with that of biota. Systematic study of floral and spores/pollen assemblages, particularly in the sections of interbedded marine and non-marine deposits, makes clear the chronostrati-graphic succession of floral associations and shows the possibility of their application for subdivision and correlation of the continental deposits of Priamurie. Tire coastal-marine environment of the residual post-collisional sublatitudinal basins in the uestern part of Priamurie （Upper Amur and Dep basins） was replaced by the continental in the late Middle Jurassic and in the eastern part in the Berriasian-Valanginian （Torom Basin）. Similar environmental change commenced in the submeridional rift basins： the Bureya Basin in the Callovian and the Partizansk Basin in the Hauterivian. Changes in ecosystems ocemTed frequently during the Middle Jurassic-Ne- ocomian, but the most substantial changes took place in the late Middle Jurassic and in the end of Late Jurassie.展开更多
文摘The paper describes the sedimentary features and biostratigraphy of the transitional Jurassic to Cretaceous deposits in the continental basins of Priamurie formed after the collision between the Siberian and North China blocks. In Upper Priamurie, the collision occurred in the late Early Jurassic as dated by the emplacement of the post-collisional granites （ 191 Ma）. While in Lower Priamurie and West Priokhotie it could take place in the late Middle Jurassic on the basis of fossil evidence from an aceretionary turbidite complex. This event reflected the environmental change from coastal-marine to alluvial plains, often boggy, where coals aecmnulated. The environinental change is in harmony with that of biota. Systematic study of floral and spores/pollen assemblages, particularly in the sections of interbedded marine and non-marine deposits, makes clear the chronostrati-graphic succession of floral associations and shows the possibility of their application for subdivision and correlation of the continental deposits of Priamurie. Tire coastal-marine environment of the residual post-collisional sublatitudinal basins in the uestern part of Priamurie （Upper Amur and Dep basins） was replaced by the continental in the late Middle Jurassic and in the eastern part in the Berriasian-Valanginian （Torom Basin）. Similar environmental change commenced in the submeridional rift basins： the Bureya Basin in the Callovian and the Partizansk Basin in the Hauterivian. Changes in ecosystems ocemTed frequently during the Middle Jurassic-Ne- ocomian, but the most substantial changes took place in the late Middle Jurassic and in the end of Late Jurassie.
