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
The shortfall of timber resource in China constantly keeps about 150 million m3, which mainly relies on import to fill in the gap. However, Russia, the key timber supply state of China, has encouraged the development ...The shortfall of timber resource in China constantly keeps about 150 million m3, which mainly relies on import to fill in the gap. However, Russia, the key timber supply state of China, has encouraged the development of its national intensive timber processing and therefore the Russian Far East Region started to gradually restrict log export. To this end, this paper analyzes the situation of forest industry and timber production in Russian Far East and discusses the current status and existing problems in timber trade between Russian Far East and China. At the end, the paper presents policy recommendation for future timber trade between Russian Far East and China and views their forestry cooperation prospect.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.
基金Supported by National Key Basic Research Plan of China (Grant No.2005CB724801)
文摘The shortfall of timber resource in China constantly keeps about 150 million m3, which mainly relies on import to fill in the gap. However, Russia, the key timber supply state of China, has encouraged the development of its national intensive timber processing and therefore the Russian Far East Region started to gradually restrict log export. To this end, this paper analyzes the situation of forest industry and timber production in Russian Far East and discusses the current status and existing problems in timber trade between Russian Far East and China. At the end, the paper presents policy recommendation for future timber trade between Russian Far East and China and views their forestry cooperation prospect.