Development of new, integrated computer modelling and inversion methods for applied geophysics and for joint geology-geophysics Earth modelling

拟议研究方案的目标是改进地球物理测量数据的计算机建模和解释方法，使之能够真正与现代计算机化地质建模技术相结合。 人们普遍认为，易发现的矿床都已被发现。由于赋存的地质环境的复杂性，矿床往往被遗漏，特别是当赋存岩石的几何和构造关系复杂且难以解体时。 在过去十年左右的时间里，地球物理反演软件的使用已经变得普遍，该软件可以根据大多数类型的地球物理测量数据来构造物理属性(即地球物理地球模型)的3D地下分布。事实证明，在地质环境不是特别复杂的情况下，现有的反演技术能够成功地提供有关矿床位置、深度、大小和成分的可靠、可靠的定量信息。然而，现有的反演技术本身在地下较复杂的情况下识别特征的能力有限，不适合与地质建模方法相结合。 最近，已经开发了用于构建3D地质模型的方法和软件，即包括表示岩石单元、断层和矿床轮廓之间的接触的线框表面的计算机模型。这种模型基本上是地下的3D地图，然后可以用来更好地了解矿藏与其周围地质特征之间的空间和结构关系，并提供对矿藏的位置、深度和大小的定量估计。然而，这种地质建模方法使用的数据仅限于非常稀疏的点测量，所构建的表面是在没有地质数据的大片地下进行外推的。 将这两个过程结合成一个单一的、集成的过程将产生能够处理比目前可能的更复杂的地下场景的地球建模能力：构造地质信息将减少地球物理反演的不唯一性和模糊性，并且关于更大规模、平均物理性质分布的地球物理信息将指导整个地下地质表面的外推， 因此，新的方法将特别有利于矿产勘探业，这是加拿大经济的重要贡献，以及它对新矿藏的寻找。这项研究还将极大地促进我们对计算地球物理方法的认识和理解。

The goal of the proposed research programme is to develop improved computer modelling and interpretation methods for geophysical survey data that can be truly integrated with modern computerized geological model-building techniques. It is generally recognized that the easy-to-find ore deposits have all been discovered. Deposits are often missed because of the complexity of the geological environment in which they are hosted, especially when the geometrical and structural relationships of the host rocks are complicated and hard to unravel. In the last decade or so, the use of geophysical inversion software that can construct 3D subsurface distributions of a physical property (i.e., a geophysical Earth model) from most types of geophysical survey data has become widespread. Existing inversion technology has proven to be successful in providing reliable, robust quantitative information about the location, depth, size and composition of ore deposits when the geological environment is not particularly complicated. However, on its own, existing inversion technology is limited in its ability to distinguish features when the subsurface is more complex, and it is not suited for integration with geological modelling methods. Recently, methodology and software for constructing 3D geological models, i.e, computer models comprising wireframe surfaces that represent contacts between rock units, faults, and outlines of ore deposits, have been developed. Such models, which are essentially 3D maps of the subsurface, can then be used to better understand the spatial and structural relationships between an ore deposit and its surrounding geological features, and to provide quantitative estimates of the location, depth and size of a mineral deposit. However, the data that such geological model-building methods use is limited to very sparse point measurements and the constructed surfaces are extrapolated throughout large expanses of the subsurface where no geological data exists. Combining these two processes into a single, integrated procedure will result in Earth modelling capabilities that can handle significantly more complex subsurface scenarios than is currently possible: the structural geological information will reduce the non-uniqueness and indistinctness of the geophysical inversion, and the geophysical information about the larger-scale, averaged physical property distribution will guide extrapolation of the geological surfaces throughout the subsurface, As such, the new methods will be of particular benefit to the mineral exploration industry, which is a significant contributor to Canada's economy, and its search for new ore deposits. The research will also significantly advance our knowledge and understanding of computational geophysical methods.