摘要:
滇西高原的隆升引起莺歌海盆地的沉积速率、沉积通量的陡增、层序界面间的不整合,高原内部盆地沉积速率增加、充填序列改变、间歇性隆升剥蚀。根据这些响应标志重塑了滇西高原的隆升历史 :(1 ) 2 3~ 1 9Ma的初始隆升;(2 ) 1 6.2~ 1 1Ma的快速隆升;(3) 1 1~ 5.3Ma的剥蚀夷平;(4) 5.3~ 1.6Ma的急剧隆升,滇西高原基本定型;(5)1.6~ 0Ma的剥蚀 -隆升加速期。
Abstract:
The Western Yunnan Plateau (WYP) is located at the southeastern Qinghai- Tib et plateau.The Yinggehai at the southeast termination of the Red River Fault Zo ne is a new (mainly Neogene) strike-slip basin which is one of the peripheral b asins of the WYP.The WYP uplift results in not only sharply increasing of sedime ntation rate and sedimentation flux in the Yinggehai basin,discordance of se qu ence interface,violently increasing of clastic supplying volume from the WYP,but also increasing of sedimentation rate in the interior plateau basins,changing o f filling sequence and uplift-denudation peridically.The history of tectonic su bsidence is very similiar in both Yinggehai basin and interior plateau basin s and,t hey kept basically the same pace in tectonic subsidence.The marks such as the ac cumu lation peak period in Yinggehai basin and interior plateau basins,the denuda tio n period of interior plateau basins,the peak period of clastic supplying from WY P denuded,respond to a rapid upliftiong of WYP.The lower accumulation rate and t h e reduction steeply of clastic supplying from WYP denuded respond to relative st able period of WYP.Based on these marks respond to uplift,we reconstruct uplifti n g history of WYP,including initial uplifting (23~19 Ma),rapid uplifting (16.2 ~11 Ma),denudation planation(11~5.3 Ma),accelerated denudation and uplift(1.6~0 Ma).T he WYP was formed basically in 5.3~1.6 Ma,the average relative to uplifting rat e wa s 0.5~0.57mm/a and maximmum in 2.5 Ma.The altitude above sea-level of WYP was uplifted regionally about 610~700 m in past 1.6 Ma.