CAJ | 학술논문

青藏高原的形成是特提斯演化的结果.本文根据区域大地构造演化和沉积学证据,将青藏高原特提斯在时间上划分为3个阶段,即早期、中期和晚期.早期从震旦纪开始至奥陶-志留纪结束,这个阶段的大洋我们称作"原特提斯".中期从泥盆纪开始至石炭-二叠纪结束,通常称这个大洋为"古特提斯".晚期从二叠纪末、三叠纪初开始一直延续到第三纪早期,这个阶段的大洋通常被称作"新特提斯".在空间上,青藏高原特提斯可以划分为3个区域相,即北区、中区和南区.上述3个阶段完全可以与空间上的3个区域相对应,原特提斯主要发育于北区,大洋消亡后的遗迹残留在青藏高原第5缝合带中,即西昆仑-阿尔金-北祁连缝合带.古特提斯主要发育于中区,大洋消亡后的遗迹残留在青藏高原第3、4缝合带中,即金沙江缝合带和昆仑南缘缝合带.新特提斯主要发育于南区,大洋主洋盆消亡后的遗迹残留在青藏高原第1缝合带中,即雅鲁藏布江缝合带,它的弧后盆地消亡后的遗迹残留在第2缝合带中,即班公湖-怒江缝合带.
청장고원적형성시특제사연화적결과.본문근거구역대지구조연화화침적학증거,장청장고원특제사재시간상화분위3개계단,즉조기、중기화만기.조기종진단기개시지오도-지류기결속,저개계단적대양아문칭작"원특제사".중기종니분기개시지석탄-이첩기결속,통상칭저개대양위"고특제사".만기종이첩기말、삼첩기초개시일직연속도제삼기조기,저개계단적대양통상피칭작"신특제사".재공간상,청장고원특제사가이화분위3개구역상,즉북구、중구화남구.상술3개계단완전가이여공간상적3개구역상대응,원특제사주요발육우북구,대양소망후적유적잔류재청장고원제5봉합대중,즉서곤륜-아이금-북기련봉합대.고특제사주요발육우중구,대양소망후적유적잔류재청장고원제3、4봉합대중,즉금사강봉합대화곤륜남연봉합대.신특제사주요발육우남구,대양주양분소망후적유적잔류재청장고원제1봉합대중,즉아로장포강봉합대,타적호후분지소망후적유적잔류재제2봉합대중,즉반공호-노강봉합대.
The Tibetan Plateau is closely related to the evolution of Tethys,and it constitutes the main scope of the eastern Tethys.According to current data from regional tectonic studies and sedimentary records,Tethys in Tibetan Plateau can be divided into three different stages,namely,Neo-Tethys,Paleo-Tethys,and Proto-Tethys,representing the Tethys in MesozoicCenozoic,Late Paleozoic and Early Paleozoic,respectively.Furthermore,they correspond to three zones in the Tibetan Plateau,namely the northern Tethyan,the central Tethyan region and the southern Tethyan region,respectively.The Proto-Tethys lies in Kunlun and Qilian Mountains in the northern Tethyan region.represented by the Fifth Suture Zone as its remnant.It had been formed in Sinian and closed in Ordovician and Silurian.It was the earliest Tethyan ocean known up to now.The Paleo-Tethys lies in Hoh Xil-Bayan Har in the central of Tibet Tethyan.represented by the Third and Fourth Suture Zones.It initiated as a back-arc basin in Ordovician and eventually formed as a basin typical oceanic crust in Carboniferous and Permian due to its continuous back-arc breaking and spreading.The Paleo-Tethys ocean still existed until the end of the Triassic.The Neo-Tethys lies in the southern Tethyan region,represented by the Yarlung Zangbo Suture Zone.It initiated on the shelf in the northern part ot Gondwanaland at the end of Permian and the beginning of Triassic and formed in Mesozoic and Cenozoic.It began to subduct northward and was consumed very soon at the end of Jurassic,however,the main oceanic basin,which is represented by the Yarlung Zangbo Suture Zone and named Neo-Tethys,didn't consume until Early-Mid Eocene.It is obvious that the Tethyan ocean moved southward step by step according to the space distribution pattern of major Tethyan oceans in different periods.The evolution of Tethys,combined with the characteristics of terranes and distribution pattern of biogeography,also indicates the plate tectonic model that the Tibetan Plateau was formed by the continuous rifting of Gondwanaland and the accretion of the Eurasia.