单斜构造区岩溶倾斜洞穴发育趋势与岩层产状相关性识别

Relationship between development of inclined karst cave and bedrock orientation in a monoclinal structure area

通过构建岩溶倾斜洞穴发育趋势面和岩层倾向面,探讨在单斜构造区岩溶倾斜洞发育趋势与岩层产状的相关性。首先,根据洞穴探测导线长度、方向、倾角等要素,以测量初始点为原点建立空间直角坐标系,将测量空间方位角转换为平面直角坐标系中的方向角,将测量数据投影在平面直角坐标系上,运用向量加法原理求出各测点平面向量及坐标,结合各测点的相对高差,运用趋势面分析方法进行一次拟合,构建洞道空间展布平面方程;其次,根据岩层产状信息在空间坐标系中构建平面方程;最后,通过计算两平面法向量的夹角,来判断洞穴空间展布平面和岩层产状平面的重合度,同时求出两平面与同一水平面的交线所成角来判断洞穴空间展布趋势面与岩层面的倾向关系。通过实例证明,该方法用于探讨单斜构造区岩层产状对倾斜洞穴发育趋势的影响识别具有一定的实用性。

In this paper,the relationship between the developmental trend of karst inclined cave and the orientation of rock formation in monoclinal structural area by constructing cave spatial distribution trend surface and rock dipping surface.Firstly,measurement initial point is regarded as original point for establishment of spatial Cartesian coordinate system according to cave exploration wire length,direction,inclination and other factors.The measurement wire is projected on the plane so that the spatial azimuth is converted to orientation angle in plane rectangular coordinate system,and the angle values are calculated.Principle of vector addition is used for calculating plane vectors and coordinates of each measured point.Relative elevation difference of each measuring point is recorded,trend surface analysis method is utilized for primary fitting,which could construct channel space distribution plane equation.Secondly,the plane equation is constructed in spatial coordinate system according to the rock orientation information.Finally,the coincidence degree of cave spatial distribution plane and rock occurrence plane is judged by calculating the angle between two plane normal vectors.Meanwhile,the trend relationship between cave spatial distribution trend surface and rock surface is judged by the angle formed by two planes and crossed line on the same level.Example analysis shows that the method is used for investigating quantitative analysis between karst cave spatial distribution and rock correlation with certain practicality and scientific value.