基于TIN的地质界面三维形态分析方法与应用

毛先成^{1, 2}，赵莹^{1, 2}，唐艳华^{1, 2}，彭正林^{1, 2}，陈进^{1, 2}，邓浩^{1, 2}

(1. 中南大学 有色金属成矿预测教育部重点实验室，湖南 长沙，410083；2. 中南大学 地球科学与信息物理学院，湖南 长沙，410083)

摘 要：现有的空间分析方法难以有效地提取地质界面空间形态这种控矿因素，针对该问题，基于三维地质建模、空间插值、地质场分析等方法，提出基于TIN模型的地质界面三维形态分析的新方法。该方法在使用三维TIN模型来模拟地质界面的基础上，使用空间几何和计算机图形学原理计算地质界面的一般几何形态参数(坡度、夹角等)和距离场，然后利用空间插值和趋势剩余分析技术，分级提取出地质界面的总体形态趋势以及形态起伏，最后以栅格模型来表达控矿地质因素场，实现各种控矿地质因素的定量模拟。以福建丁家山铅锌矿床的主要控矿地质界面为例进行三维形态分析。研究结果表明：采用基于TIN的地质界面三维形态分析方法能够更精确、更高效的提取地质界面的各种形态参数，有效的定量化表达控矿地质因素，在隐伏矿体立体定量预测中具有重要意义。

关键词：地质界面；三维形态分析；不规则三角网；控矿地质因素

Three-dimensional morphological analysis method for geological interfaces based on TIN and its application

MAO Xiancheng^{1, 2}, ZHAO Ying^{1, 2}, TANG Yanhua^{1, 2}, PENG Zhenglin¹, CHEN Jin^{1, 2}, DENG Hao^{1, 2}

(1. Ministry of Education Key Laboratory of Metallogenic Prediction of Nonferrous Metals,Central South University, Changsha 410083, China;2. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China)

Abstract:Existing spatial analysis methods cannot effectively extract and express the ore-controlling factors of geological interface shapes. By combining three-dimensional geological modeling, spatial interpolation, geological field analysis method, a new method of morphological analysis method for geological interfaces based on TIN model is proposed. The method uses three-dimensional TIN model to simulate geological interfaces, and calculate the general geometry parameters (slope, angle, etc.) and distance field of geological surfaces with geometric and computer graphics principles. Then, based on space interpolation and trend-residue analysis, hierarchical trends and fluctuations of geological interfaces are extracted. Finally quantitative simulation of geological ore-controlling factors is achieved by using 3D raster model to express fields of ore-controlling factors. Taking the Dingjiashan lead-zinc deposit in Fujian province as a case, the main ore-controlling geological interfaces of the deposit were analyzed by using the 3D morphological analysis method. The results show that the method is efficient and accurate for extraction of various geological shape parameters, and it could be used to quantitatively express geological ore-controlling factors, which has important significance in stereoscopic quantitative prediction of concealed ore bodies.

Key words:geological interfaces; 3D morphological analysis; triangulated irregular network; geological ore-controlling factors