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黄土高原晚第三纪红黏土地层的成因和沉积环境在相当长的时期里是存有争议的科学问题,由于它涉及到红黏土地层能否提取正确的古环境信息等最基础的问题,近年来越来越受到学术界关注.通过对甘肃西峰赵家川晚第三纪红黏土蜗牛化石组合的组成以及保存方式的系统分析,认为红黏土中的陆生蜗牛化石为原生的生物群落,反映了原始的沉积环境;红黏土中大多数属种为第四纪黄土地层的常见类型,表明红黏土与黄土的形成环境背景是相同的,蜗牛化石的组成提供了该区红黏土陆相风尘沉积成因的生物证据.西峰红黏土蜗牛化石组合记录了6.2~2.4MaBP时期4次大的环境变化,6.2~5.4MaBP为干冷的气候环境,自5.4MaBP之后,气候从暖湿逐步变得冷干,呈明显的阶段性的变化.陆生蜗牛化石记录的气候环境演变历史与北极冰盖的起源、演化和青藏高原隆升在大的时段上具有很好的一致性,表明陆生蜗牛是指示晚第三纪环境变化敏感的环境指标.
The origin and sedimentary environment of the Late Triassic red clay stratum in the Loess Plateau has been a controversial scientific issue for a long period of time. Due to its involvement in the most basic problems of whether the red clay stratum can extract correct paleoenvironmental information, More and more concerned by the academia.Through the systematic analysis of the compositions and preservation ways of the late Triassic red clay snail fossils in the Xijiang Zhaojiachuan, Gansu, the terrestrial snail fossils in the red clay are considered as the original biomes, reflecting the original The most common genera of red clay are the common types of Quaternary loess stratum, which indicates that the formation background of red clay and loess is the same, and the composition of snail fossils provides the origin of continental clay dust deposition in this area Bioaccumulation Xifeng red clay snail fossil assemblage recorded four major environmental changes during the period of 6.2 ~ 2.4MaBP, 6.2 ~ 5.4MaBP was dry and cold climate environment, since 5.4MaBP, the climate gradually became warm and humid from warm and humid, showing obvious . The history of climatic environment recorded by terrestrial snail fossils is consistent with the origin and evolution of the Arctic ice sheet and the uplift of the Qinghai-Tibet Plateau over a long period of time Consistency, suggesting that terrestrial snails is an indication of the Neogene sensitive environmental indicators of environmental change.