Abstract:

Yangjiaping,Northwestern Hunan,is situated in the west margin of Central Hubei carbonate platform.In the Cambrian,there occurred successively a series of catastrophic events in the study area,including oceanic anoxic event,turbidity event and tempest event.According to the petrological characterisitics of the black rock series and the facts that they occur on the bases of the rapid transgressional sequences and are distributed widely in South China and the whole world,the formation of the black rock series should be related to the meteorite impact,the break up of pancontinent and the eustatic sealevel abrupt rising between the Sinian and Cambrian.The turbidity events and tempest events were all strong local catastrophic events.The former resulted in phosphorous turbidites and calcareous turbidites,their induced factors were related to tempest activities;the latter resulted in near source tempestites and scoured basement autochthonous tempestites.

Key words: Cambrian System, Northwestern Hunan, oceanic anoxic event, turbidity event, tempest event