三维地质结构模型是地质空间内地质构造和地质体对象边界的数字化表征模型。随着地质数据矢量栅格一体化集成和地质数据空间查询分析需求增多,构建统一表达地质结构的一体化空间数据模型成为三维地质信息科学领域需要解决的基础性问题之一。针对规则网格、PillarGrid和SBRT模型等难以实现复杂地质结构的精细表达问题,本研究提出InterfaceGrid数据模型,充分考虑地质结构和属性的地下分布具有极强的非均匀性、不连续性和空间多尺度性,且表现出纵向分层特性和多属性场耦合的相关性。基于InterfaceGrid设计理论模型和数据结构,构建统一描述三维地质结构的InterfaceGrid数据模型,实现复杂地质结构的矢量栅格一体化表达。基于GeoAtom地原子理论构建InterfaceGrid的形式化表达框架,提出InterfaceGrid的构建流程,以及基于InterfaceGrid模型设计数据更新和空间查询算法。采用GPU光线投射和自适应采样策略实现地质网格的体可视化和在线浏览,结果显示,与SBRT模型相比较,InterfaceGrid能够更加真实地描述地质边界情况,提高了三维地质结构模型的准确性。在全球岩石圈三维网格化构建应用InterfaceGrid,验证了InterfaceGrid在大规模地质数据组织管理中的适用性,相比较PillarGrid数据量减少约1/3,更加适合基于大数据量的网络地学应用服务。

3D structural geological models are a digital representation of geological structures and geological body (object) boundaries in geological space. With the increasing demands for raster and vector integration and spatial query and analysis of geological data, the construction of integrated spatial data model for unified expression of geological structures has become one of the basic problems of 3D geological information science. To address the problem of expressing complex geological structures by regular grids, PillarGrid, Stack-Based Representation of Terrains (SBRT), etc., this study proposes the InterfaceGrid data model to fully consider that the distribution of geological structures/attributes underground exhibit strong non-uniformity, discontinuity, spatially multi-scaled, and show longitudinal stratification and multi-attribute field coupling. By design, this InterfaceGrid data model can uniformly describe 3D geological structures and realize the vector raster integration expression of complex geological structures. In this paper, the formal expression framework of InterfaceGrid is constructed based on GeoAtom theory; the construction process of the InterfaceGrid model is described; and the data update and spatial query algorithms are designed based on the InterfaceGrid model. The volume visualization and online browsing of geological grid are realized using GPU ray casting and adaptive sampling strategy. Compared with SBRT, InterfaceGrid can more truly describe the geological boundaries and improve the accuracy of 3D structural geological models. The application of InterfaceGrid in the 3D grid construction of the global lithosphere verifies the applicability of InterfaceGrid in the organization and management of large-scale geological data. Compared with PillarGrid, the data volume is reduced by about 1/3 in InterfaceGrid, making it more suitable for the data-intensive geoscience network applications.