[关键词]
[摘要]
最近从藏北安多地区中侏罗统发现较丰富的菊石类化石,巴通期的菊石有OxyceritesoppeliElmi,Ho moeoplanulitescf. homoeomorphus(Buckman),H. cf. acuticosta(Roemer), Choffatiacf. vicentiMangold, Siemiradzkiacf. matisconensis(Lissajous), Proceritessp., Neuquenicerascf. yokoyamaiKobayashiandFukada和Indosphinctessp.。卡洛夫期的菊石有Oxyceritescf. subcotarius(Oppel), Macrocephalites? sp., Homoeoplanulitescf. furculus(Neumayr),Indospinctes(Elatmites) cf. reveliMangold和Reineckeitessp.。其中Indosphinctes,Indospinctes(Elatmites),Neu queniceras,Siemiradzkia和Procerites等属(或亚属)在西藏北部地区为首次报道。安多地区中—晚巴通期和早卡洛夫期菊石动物群凸现较强的地方性色彩; 晚巴通期ORBIS菊石带和早卡洛夫期KOENIGI菊石带是藏北地区菊石动物群扩散的重要时期。
[Key word]
[Abstract]
New collections of ammonites have been recently carried out in the Amdo area, northern Tibet. The Bathonian ammonites have been referred to Oxycerites oppeli Elmi,Homoeoplanulites cf. homoeomorphus (Buckman),H. cf. acuticosta (Roemer), Choffatia cf. vicenti Mangold, Siemiradzkia cf. matisconensis (Lissajous), Procerites sp., Neuqueniceras cf. yokoyamai Kobayashi and Fukada, and Indosphinctes sp. The Callovian ammonites include Oxycerites cf. subcotarius (Oppel),Macrocephalites? sp., Homoeoplanulites cf. furculus (Neumayr), Indospinctes (Elatmites) cf. reveli Mangold and Reineckeites sp. At generic level Indosphinctes,Indospinctes (Elatmites),Neuqueniceras, Siemiradzkia and Procerites are found in North Tibet for the first time, suggesting an age from middle Bathonian to early Callovian. The Middle Jurassic ammonites in this area exhibit a strong endemicity. Both ORBIS of the Upper Bathonian and KOENIGI zones of the Lower Callovian are significant intervals for faunal dispersal.
[中图分类号]
Q915.818.4
[基金项目]
国家自然科学基金(No. 40072001)资助课题
