Abstract:

Ice-molten sedimentary structure is a kind of ice-induced sedimentary structure controlled mainly by ice.Ice-molten sedimentary structures produced in not only glacial zone and permafrost but also seasonal frozen zone．Through field observations,seven ice-molten sedimentary structures,i.e.ice-molten water flow mark，ice-induced rip current mark,ice-molten dome(mark)，ice-induced silt or mud slices,ice-induced mud-sand stalagmite，ice-induced pisolite,ice-induced rhizome,are recognized in the Yellow River delta and described in this paper,Totally,ice-molten sedimentary structures formed under condition of low temperature,fresh sediments saturated with water.An analysis by synthesis about the characters of modern ice-molten sedimentary structures and ancient ice-molten sedimentary structures in Maershan Member,Laiyang Formation in the Jiaolai basin,east China,shows that ice-molten sedimentary structures are important for the identification of sedimentary environments such as river channel,delta and tidal flat,and low temperature climate.Additionally，systematical classification on ice-formed sedimentary structures is made,and the relationship on characters of ice-formed sedimentary structures between permafrost zone and seasonal frozen zone is discussed in this paper.Though scales and species of ice-formed sedimentary structures produced from permafrost zone and seasonal frozen zone are great different,their mechanisms of formation are basically similar.

Key words: ice-molten sedimentary structure, ice-formed sedimentary structure, sedimentary environment, climate, the Yellow River deIta