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在以往的沉积学研究中，常常用剖面中的相对水深变化来讨论海平面的变化规律。本文通过对塔里木盆地北部寒武纪上超点变化曲线与肖尔布拉克地区寒武系露头剖面中相对水深变化曲线的对比研究发现，上超点变化曲线与相对水深变化曲线具有明显的差异，前者在寒武纪呈持续上升趋势，而后者除早期有一快速上升外，总体呈持续下降趋势，这说明相对水深变化虽与海平面变化存在着本质的联系，但单凭露头剖面中相对水深变化的研究是难以对海平面变化作出正确估价的，还必须综合考虑基底沉降、沉积物供给等多种因素的影响。计算机模拟结果也证实了，在碳酸盐台地的浅水处，当基底沉降速率较低时，无论是海平面上升还是下降时期，相对水深均呈现持续下降趋势。为了能从露头剖面的地层层序中来了解海平面的变化规律，本文应用作者改进后的Ｆｉｓｃｈｅｒ图解和数学方法对肖尔布拉克寒武系剖面进行了海平面变化的重建，结果发现，它们与上超点变化曲线的变化趋势完全一致。这充分说明了海平面变化对沉积层序的控制作用，同时也告诉我们，不能简单地利用露头剖面中的相对水深变化来研究地质历史时期的海平面变化规律。只有在排除了不同沉积背景上基底沉降速率和沉积物供给速率对沉积层序的控制效应后，才能从露头剖面?
In the past sedimentology research, the change of sea level was often discussed by the change of relative water depth in the section. In this paper, a comparative study on the relative water depth curves in the northern Cambrian of the Tarim Basin and the Cambrian outcrop sections in the Shorbuluk region shows that there is a significant difference between the curves of the over-superstratum and the relative water depths, The former shows a continuous upward trend during the Cambrian period, while the latter shows a continuous downward trend except for a rapid increase in the early period. This shows that although the relative water depth is intrinsically linked with the sea level change, Of the study is difficult to correct the sea level to make a correct assessment, we must also consider the substrate sedimentation, sediment supply and other factors. Computer simulation results also confirmed that in the shallow water of carbonate platform, when the substrate sedimentation rate is low, both the sea level rise or fall period, the relative water depth shows a downward trend. In order to understand the variation of sea level from the sequence of outcrops, this paper uses the improved Fischer diagram and mathematical method to reconstruct the sea level changes of the Shoballak profile, and found that they The trend of change with the super-point curve is exactly the same. This fully illustrates the controlling role of sea level changes on sedimentary sequence and tells us that the change of relative water depth in outcrop profile can not be simply used to study the sea level change law in geological history. Only from the outcrop profile can we remove the controlling effect of sedimentation rate and sediment supply rate on sedimentary sequences on different sedimentary backgrounds?