摘要
从河道类型的划分、河床演变与河型转换、河道沉积与河流砂体的建筑结构要素、河漫滩沉积、季节性河流与分支河流体系、河流沉积相模式、河流沉积学研究技术与方法等方面对国内外河流沉积模式的研究进展进行了综述,认为近十年来河流沉积学的理论和方法都发生了重要的变化。地貌学家、沉积学家和工程师认识到河道形态是连续可变的,而不是只有4~40多个端点类型。河床的演变受河床比降、流量变幅、河岸沉积物粒度构成、气候、植被以及构造沉降速率等多方面的影响。垂向剖面分析法难以对古河流类型做出正确的判断,运用建筑结构要素分析法重建河道内大型底形的地貌形态是河型判别和河流相模式重建的正确方法。河漫滩是河流沉积事件记录最为齐全的部位,对河漫滩、天然堤和泛滥平原沉积层序的研究能够揭示更多古河流沉积过程以及古环境、古气候和古生物方面的信息。对季节性河流、受季风强烈影响地区的河流、以及不同气候带河流所发育的独特沉积构造和建筑结构要素的研究不断增加。分支河流体系的概念得到越来越多的应用,但也得到不少质疑。我国学者应当注重对现代河流地貌形态和沉积过程的观察,把河床演变学的定量方法与沉积学的观点、理论和资料相结合,利用露头、三维地震资料和探地雷达技术建立河流砂体内部建筑结构信息数据库,加强对古河流河漫滩和泛滥平原的沉积过程、特征及其控制因素的研究,加强对不同构造和气候条件下河流沉积的差异性研究,不断发展河流沉积学研究技术,加强河流沉积学实验室建设和研究队伍建设,加强国际交流与合作,使我国河流沉积学为国家经济社会发展提供更加有力和有效的支撑,为推动国际河流沉积学发展做出中国人自己的贡献。
This paper reviewed recent development in the areas including river pattern classification,channel evolution and transformation,fluvial channel architectural elements distribution,overbank deposition,ephemeral river and distributive fluvial system,fluvial facies models,and new technologies for fluvial sedimentological research.The authors concluded that fluvial sedimentology has witnessed significant improvement in the theory and the methodology since the past two decades.Some geomorphologists,sedimentologists,and engineers recognize a continuum of channel forms rather than only several tens of end members.Channel transitions are controlled by river bed gradient,variations in river discharge,composition of river bank materials,climate,vegetation and tectonic activities along their courses.Vertical profile analysis has great difficulties in differentiating ancient fluvial channel pattern in rock record.Therefore,macro-form geometrical reconstruction based on analysis of architectural element may be the right way to recognize ancestral river pattern and construct fluvial facies model.Overbank deposits record most complete information regarding ancient floods and palaeoenvironmental,palaeoclimatic and palaeontological information of a river.Ephemeral,seasonal,and strong monsoon-affected tropical and sub-tropical rivers have unique sedimentary structures and architectural elements.Distributive fluvial system （DFS） has been received more attentions though it has some doubts.Chinese fluvial sedimentologists need to investigate more modern rivers to observe their geomorphological characteristics and depositional processes,and should refer the quantitative methods of river evolution research and integrate them with sedimentological methods.We should build up the database in fluvial architectural element by using outcrop anatomy,3D seismic and GPR technology.We should improve our research about overbank and floodplain processes,as well as the depositional regime of rivers in different climate zones.We need to develop new techniques,strengthen research team and laboratory construction,and enhance international exchange and cooperation.The ultimate objective is to make Chinese fluvial sedimentology to provide more strong and effective support for national social and economic development,and to make our own contributions to the development of fluvial sedimentology in the world.
出处
《沉积学报》
CAS
CSCD
北大核心
2017年第5期926-944,共19页
Acta Sedimentologica Sinica
基金
国家自然科学基金项目(41772094
41302096)
国家科技重大专项(2016ZX05027-002-007)~~
关键词
河流
河流沉积学
河道
建筑结构要素
相模式
综述
river
fluvial sedimentology
fluvial channel
architectural element
facies model
review
