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山东沂水地区早中寒武世地层同陆表海沉积．根据岩性组合、沉积旋回、岩相、相序以及地层结构、层序界面标志等特征，将区内中下家武统划分９个层序（包括１个Ⅰ型、１个Ⅱ型和７个Ⅱ型展序）和识别出１０个层序界面．Ⅰ型和Ⅱ垫层序均由海侵体系域和高水位体系域组成，凝缩段不甚发育．Ⅲ型层序由凝缩段与高水位体系域组成．地球化学研究表明：微量元素（Ｎｉ，Ｖ，Ｂ，Ｓｒ）含量及Ｓｔ／Ｂａ比值在海侵体系域逐渐增高，在高水位体系域中降低；而δ１３Ｃ，δ１８Ｏ和Ｂａ元素含量和古温度则相反．上述各值在层序界面及附近，一般表现为突变．层序的形成是盆地构造沉降，全球海平面升降、沉积物供应速度及古气候四大因素的综合作用结果．本文建立了Ｆ４断到以西早、中寒武武世地层空间格架，总结了由北向南地层厚度增大，沉积环境由浅到深变化规律．从而明确了岩石地层单位的空间分布关系。
Precambrian Cambrian strata in Yishui area of Shandong are deposited with the continental shelf. According to lithologic assemblage, sedimentary cycle, lithofacies, facies sequence, stratigraphic structure and sequence boundary markers, the middle-lower Wuzhan area is divided into 9 sequences (including 1 type Ⅰ, 1 type Ⅱ and 7 A type Ⅱ sequence) and identify 10 sequence interfaces. The type Ⅰ and Ⅱ cushion sequences are composed of transgressive system tract and high water system tract, and the condensation section is not well developed. Type Ⅲ sequence consists of condensation section and high water system tract. Geochemical studies show that the contents of trace elements (Ni, V, B, Sr) and St / Ba increase gradually in the transgressive system tract and decrease in the high-water system tract. The contents of δ13C, δ18O and Ba and the palaeoclimate in contrast. The above values in the sequence interface and near the general performance of the mutation. The formation of the sequence is the result of the combined action of the four factors of basin structural settlement, global sea level rise and fall, sediment supply speed and paleoclimate. This paper established the F4 fault to the early and middle Cambrian stratigraphic framework in the west of the strata, and summarized the variation of the sedimentary environment from shallow to deep with the thickness increasing from north to south. Thus, the spatial distribution of lithostratigraphic unit is clarified.