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沉积物沉积环境的判别对于沉积物物源的分析、古地理重建、古环境和古气候的恢复均具有重要的意义。通过研究发现鄱阳湖松门山岛沉积颗粒表面具有丰富的特征,主要是:贝壳状断口、V形撞击坑、撞击沟、碟形撞击坑与新月形撞击坑等。利用扫描电镜对鄱阳湖松门山岛的样品进行了研究,发现鄱阳湖松门山岛的水下砂体样品普遍可见贝壳状断口、V形撞击坑与撞击沟等,说明该类样品为水成环境;沙丘样品普遍可见标准的碟形撞击坑与新月形撞击坑等,说明为风成环境;处于水下砂体和沙丘过渡带之间的样品上述现象几乎均存在,说明这些沉积物经过风成和水成两种环境的共同改造。分析水成和风成环境下的石英颗粒的不同特征,对这些特征利用线测法进行统计分析,发现不同环境下石英颗粒的特征不仅可以定性判别,还可以半定量区分:在水成环境下的样品撞击沟所占的比值高,通常大于30%,而在风成环境中的样品碟形坑所占的比值高,通常大于40%。这一发现对该地区的沉积环境分析有指导作用,并且对于该地区沉积微相划分具有一定意义。
Sediment sedimentary environment discrimination For sediment source analysis, paleogeographic reconstruction, paleoenvironment and paleoclimate recovery are of great significance. Through the research, it is found that the surface of the sedimentary particles in Songmen Mountain Island of Poyang Lake is rich in features, such as shell-shaped fracture, V-shaped impact crater, impact ditch, crustal craters and crescent-shaped impact crater. Scanning electron microscopy of Songyangshan Island in Poyang Lake samples were studied and found that the Songshan Island, Poyang Lake, underwater sand samples generally see the shell-shaped fracture, V-shaped impact crater and impact groove, indicating that such samples are water Into the environment; sand dune samples generally visible standard craters craters and crescent craters, etc., described as aeolian environment; in the underwater sand body and dune transitional zone of the sample above-mentioned phenomena exist, indicating that these sediments After the wind and water into the environment of the two common transformation. Analyze the different characteristics of quartz particles under the conditions of water and wind, and make statistical analysis of these characteristics by using the line method. It is found that the characteristics of quartz particles under different environments can not only be qualitatively discriminated, but also be semi-quantitatively distinguished: The ratio of the sample impact gully is high, usually greater than 30%, whereas the ratio of sample craters in windy environments is high, usually greater than 40%. This finding has a guiding role in the analysis of sedimentary environment in the area and is of some significance for the classification of sedimentary microfacies in the area.