郯庐断裂带演化动力学——多力源多时期分段作用模式

提出了郯庐断裂带的演化动力学--多力源多时期分段作用模式.早-中侏罗世,扬子与华北地块碰撞后的持续会聚力、古太平洋板块的挤压力(安第斯型)联合作用于郯庐断裂带,产生了左旋压扭活动.晚侏罗世,西太平洋型的古太平洋板块挤压力作用机制率先作用于中国大陆边缘的北部地区,并一直持续到古近纪.其在郯庐断裂带中、北段诱发出上地幔上涌力,使其产生了右旋拉张活动;郯庐断裂带南段直至晚白垩世才受到这种机制作用.晚新生代以来,西太平洋俯冲带后退,上地幔上涌力作用已退到边缘海地区,郯庐断裂带全段受到边缘海地区上地幔上涌力诱发的次级挤压作用力,形成了右旋挤压活动.

Dynamics of the evolution of the Tanlu fault zone: A multiforce-in-multiphase acting model

This paper proposes a new dynamic model to explain the evolution of the Tanlu fault zone,that is,the multiforce-in-multiphase acting(on the Tanlu fault zone) model. In the Early and Middle Jurassic,two kinds of forces,the lasting convergent force(NNE-SSW orientation) after Late Triassic collision of Yangtze and North China blocks and the force(NW sense) from paleo-Pacific plate,acted on the paleo-Asian continental margin(Andes-type) to produce a compressional and sinistral strike-slip displacement of the Tanlu fault zone.In Late Jurassic,the northern paleo-Asian continental margin converted to the West Pacifictype,and the Pacific Plate's subduction induced the upper mantle's upward movement on the middle and northern Tanlu fault zone,which resulted in an extensional and dextral displacement of the Tanlu fault zone.The similar action did not take place on the southern section of the Tanlu fault zone until Late Cretaceous.Since Late Cenozoic,the Pacific Plate's subduction has withdrawn and its induced upper mantle's upward movement also has withdrawn to the present Marginal Sea area.The NWW-sense compression deriving from sub-convection of the upper mantle under the above Marginal Sea area makes the Tanlu fault zone slip compressionally and dextrally.