摘要
The development of a plateau is an integral part of the evolution of recent large orogens. This is suggested by the presence of wide regions of high topographic relief in many Phanerozoic collisional belts, with the Tibetan, Anatolian, Altiplano and Colorado plateaus forming the most often cited examples. To date, plateaus have not been documented in Proterozoic orogens. However, if large Proterozoic convergent belts developed plateaus, evidence should be preserved in the geologic record.Proterozoic belts expose deeper crustal levels that are not directly accessible in modern analogues. Therefore, if they represent the final product of a plateau style evolution, their study may give direct insight on the nature of the middle to lower crust beneath modern orogenic plateaus. The Grenville Province of the Canadian Shield is a Mesoproterozoic continental collision belt of Himalayan scale that contains various lines of evidence suggesting an early plateau\|type evolution. Here we discuss this evidence and draw comparisons with the prime example of a present day plateau in a continental collision setting, the Tibetan plateau.
The development of a plateau is an integral part of the evolution of recent large orogens. This is suggested by the presence of wide regions of high topographic relief in many Phanerozoic collisional belts, with the Tibetan, Anatolian, Altiplano and Colorado plateaus forming the most often cited examples. To date, plateaus have not been documented in Proterozoic orogens. However, if large Proterozoic convergent belts developed plateaus, evidence should be preserved in the geologic record.Proterozoic belts expose deeper crustal levels that are not directly accessible in modern analogues. Therefore, if they represent the final product of a plateau style evolution, their study may give direct insight on the nature of the middle to lower crust beneath modern orogenic plateaus. The Grenville Province of the Canadian Shield is a Mesoproterozoic continental collision belt of Himalayan scale that contains various lines of evidence suggesting an early plateau\|type evolution. Here we discuss this evidence and draw comparisons with the prime example of a present day plateau in a continental collision setting, the Tibetan plateau.
出处
《地学前缘》
EI
CAS
CSCD
2000年第S1期320-321,共2页
Earth Science Frontiers
