Study On The Division And Sedimentary Facies Of The Quondam Kangtuo Formation In Rongma Area,Nima County,Tibet

Based on the 1:5 000 regional geological mapping,research quondam Kangtog Formation sedimentary facies and depositional environment in Rongma area,Nima County,Tibet,made the following main results and understanding:(1)Based on the field measurements,according to lithology,lithofacies characteristics and regional stratigraphic correlation,the quondam "Kangtuo Formation" were determined,the stratigraphic division of the lower Cretaceous Abushan Formation,Paleogene Eocene Eocene Niubao Formation and Neogene Kangtog Formation.(2)According to the lithology,sedimentary structure and fossil character,in Abushan Formation,Niubao Formation and Kangtog Formation is divided into 3 sedimentary facies,6 sedimentary subfacies and 11 microfacies.(3)According to the profile of phase structure,the quondam "Kangtog Formation" can be divided into at least 5 sedimentary cycles,including Abushan Formation 1,Niubao Formation 3 and Kangtog Formation 1.Taking into account that there are no peaks and no bottom in each formation,the actual cycle number should be more.