通过对沧州CZ01孔岩芯野外描述,采样以及室内粒度分析和光释光(OSL)年代测定,探讨了沧州地区晚更新世以来的环境演变过程。结果表明,该岩芯垂直剖面沉积物颗粒基本构成是以黏土、粉砂、砂为主,沉积环境变化频繁。根据岩性特征及粒度参数特征可以划分为3大阶段:深度201.2～159.6 m为阶段Ⅰ,年代对应于200～128 ka B.P.,为中更新世晚期河流相与河湖交替沉积环境,下部以灰色-灰黄色粉细砂、细砂及中细砂为主,为河流相沉积,上部主要为棕黄色、灰黄色黏土、粉砂质黏土,为河湖相沉积;深度159.5～26.6 m为阶段Ⅱ,年代对应于128～12 ka B.P.,为晚更新世两个完整的沉积旋回,沉积物粒度经历了由粗-细-粗-细的变化过程。其中,第一旋回上部为灰黄色、浅黄色粉砂质黏土与黏土质粉砂,中夹灰色或灰黑色海侵相沉积的黏土质粉砂或粉砂质黏土,下部为灰色灰黄色粉细砂、中细砂,含小砾石。第二旋回上部以灰色-灰黄色黏土、黏土质粉砂为主,下部为浅灰色、灰黄色粉细砂、细砂、中砂;深度26.6～0 m为阶段Ⅲ,对应于全新世以来(12 ka B.P.以来)河湖相沉积,主要以灰色、灰黑色、灰黄色、黄灰色黏土质粉砂、黏土为主,中间分布海相层或海陆过渡相(潮滩相)的灰色、灰黑色或黑色黏土质粉砂或粉砂质黏土。
In order to study the water quality of the Shichuan River basin in Fuping,Shaanxi Province,based on improved Nemerow index method,comprehensive pollution index method and principal component analysis method,eight water quality indexes such as pH,dissolved oxygen(DO),total dissolved solids(TDS),COD,total hardness,total phosphorus,total nitrogen and Zn in three monitoring sections of Fuping section of the Shichuan River in Shaanxi Province were detected and analyzed.The results show that the water quality of the surface water in the Shichuan River basin is gradeⅢorⅣwater,that is,the water is slightly polluted and moderately polluted.It is necessary to monitor the water quality after regulation and clarify the main factors causing the water pollution.
