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鄱阳湖滨沙岭地区的沙山由交替出现的砂层与粉砂层构成。对3个剖面的调查发现,该地区发育的网纹大体可分为3种类型,Ⅰ类网纹密集且粗大,为典型的网纹,位于剖面底部,Ⅱ类网纹较稀疏、细,位于Ⅰ类网纹之上,Ⅲ类网纹界线模糊,位于剖面上部。Ⅰ类、Ⅱ类网纹属于成熟的网纹,而Ⅲ类属于不成熟的网纹。对剖面中砂层的光释光测年表明,测量等效剂量时没有出现信号饱和的问题,年剂量也没有受风化作用的影响,因而OSL年龄可以视为砂层的沉积年龄。基于砂层的沉积年龄,我们判断成熟网纹层的沉积时代早于80 ka,不成熟网纹层的沉积时代略晚于71 ka,而早于29 ka。
The sand hills in Pingshan Lake Shaling area are composed of alternating layers of sand and silt. According to the survey of three sections, there are three types of aniloxia in the area, which are generally classified into three types. Class I is dense and coarse. It is a typical anilox, which is located at the bottom of the section. Class I on top of the network, Class III network lines fuzzy, located in the upper section. Class I, II class lines are mature textured, and Class III are immature textured. Optical dating of the sand layer in the profile shows that there is no signal saturation when measuring the equivalent dose and the annual dose is not affected by weathering. Therefore, the OSL age can be regarded as the sedimentary age of the sand layer. Based on the sedimentary ages of the sand layers, we determine that the depositional age of the mature reticulate layer is earlier than 80 ka and that of the immature reticulate layer is slightly later than 71 ka and earlier than 29 ka.