大斜度井中非平行地层几何真厚度计算方法

Calculation Method of Geometric True Thickness of Non-parallel Formation in Highly Deviated Wells

正确求解地层真厚度是估算石油储量的基础,传统的求解公式采用垂直深度数据进行计算,对于非平行地层情况的适用性有所下降。为解决此问题,在非平行地层几何模型中,从更常用的测井深度数据出发,依据数学方法和三角函数关系,推导上下界面非平行条件下地层真厚度的求解公式,并讨论由于地层厚度参数变化对石油储量估算的影响。结果表明,新公式利用测井深度、地层倾角、钻孔与地层倾向夹角及井斜角等信息可准确求解非平行地层的几何真厚度,地层厚度参数变化对石油估算的影响不可忽略。该研究为容积法估算石油储量工作提出需要注意的新问题。

The correct calculation of the true thickness of the formation is the basis for estimating oil reserves.TVD data is usually used for calculation in the traditional calculation formula,which has decreased its applicability for non-parallel formation situations.In order to solve this problem,according to the geometric modeling of non-parallel formation,starting from the MLT data,based on the mathematical method and trigonometric function relationship,the formula for solving the true thickness of the formation under the condition of non-parallel upper and lower interfaces is derived,and the influence of the change of formation thickness parameters on the estimation of stone oil reserves is discussed.The results indicate that the new formula can accurately calculate the geometric true thickness of non-parallel formations using information such as logging depth,formation dip angle,angle between drilling and formation dip,and well inclination angle.The impact of changes in formation thickness parameters on oil estimation cannot be ignored.This study proposes new issues that need to be noted for the use of volumetric methods to estimate oil reserves.