顾及地质产状信息的三维地质空间场表达模式研究

With field surveying geological occurrence and boundary, coupling with geological tectonic constraints which consist of a number of faults, geologists can build up the three-dimensional shape of geological body in their minds. This project plans to restore the three-dimensional geological spatial reasoning way of geologists, which emphasizes the geological body shape controlling by the geological tectonic and geological occurrence, and to propose a three-dimensional geological spatial expression pattern based on potential field, which uses a three-dimensional geological structure field to express the full parameters of geological body, including nature, shape, topology and attribute. In this three-dimensional geological structure field, geologic time is treated as field value of the potential field, geological interface as certain isosurface of potential field, geological occurrence as gradient of potential field, and fault, intrusive or unconformity contact as discontinuity of potential field. The self-similarity of geophysical and geochemical properties in geological body is restricted by both geologic time and spatial distance, while geological tectonic movement usually folded or broke the spatial distance into unrecognizable situation after geological body formed. Based the field value of geologic time in the three-dimensional geological spatial expression pattern, combining with the deformation restoring balance model form three-dimensional geological structure field, this project plans to carry out a space-time coupling interpolation of geophysical and geochemical properties in geological body. The project will present the theory and method of the three-dimensional geological spatial field modeling, and provide various type of geosciences numerical simulations with the fine three-dimensional geological structure model and attribute model.

地质学家凭借野外测量的地质体产状和边界线，再结合若干断层组成的地质构造格架约束，就能在脑海中构建出地质体的三维形态。项目拟还原地质学家对三维地质空间的推断方式，强调地质构造格架和地质体产状对地质体形态的控制作用，建立基于位势场的三维地质空间表达模式，用三维地质构造场全参数地表达地质体的性质、形态、拓扑和属性。将地质年代作为位势场的场值，地质界面作为位势场的特定等值面，地质体产状作为位势场的梯度，不整合、侵入和断层等接触面作为位势场的不连续面。地质体物化属性的自相似性受到地质年代和空间距离的共同制约，地质构造运动又将地质体形成时的空间距离或褶曲、或错断而变得面目全非。项目通过以地质年代为场值的三维地质空间表达模式，拟结合三维地质构造场变形恢复的平衡模型，开展地质体物化属性的时空耦合插值。项目研究将形成三维地质空间场建模理论与方法，可为各类地学数值模拟提供精细的三维地质结构模型和属性模型。

地质学家凭借野外测量的地质体产状和边界线，再结合若干主要断层组成的地质构造格架约束，就能在脑海中构建出地质体的三维形态。项目还原地质学家对三维地质空间的推断方式，强调地质构造格架和地质体产状对地质体形态的控制作用。在基于HRBFs插值的地层位势场建模方法中，用三维地质构造场全参数地表达地质体的性质、形态、拓扑和属性。将地层边界的相对埋深作为位势场的属性值，位势场的梯度方向由地层产状变换得到，地质界面作为位势场的特定等值面，不整合、侵入和断层等接触面作为位势场的不连续面。项目提出的使用HRBFs插值对三维空间中地层的位置、属性和产状离散点集来构建地层位势场模型的方法，可以有效地建立起精确的地层界面，以及完整地表达地层内部的属性和产状信息。为了利用已知地质知识来降低三维地质模型的不确定性，项目提出了一种基于Bayesian-MCMC方法的三维地质模型的概率性推断框架，在三维地质隐式建模过程中，显式地考虑建模数据源的不确定性，并将地质知识（如地层厚度、地层产状、断层产状等）或地球物理勘探数据以似然函数的方式嵌入到推断框架中。利用Bayesian-MCMC迭代采样的方法对先验参数的后验概率空间进行随机采样，获得大量既满足建模数据先验分布、又符合已知地质知识似然约束的建模数据样本。项目提出的基于Bayesian-MCMC方法的概率性三维地质建模方法可充分保证三维地质模型的地质语义合理性，又为地质学家通过已知地质知识来降低三维地质模型的不确定性提供了有效的途径。项目研究形成的三维地质空间场建模理论与方法，可为各类地学数值模拟提供精细的三维地质结构模型和属性模型。