Development of level-set inversion methodology and software for radio imaging (RIM) data

无线电成像方法（RIM）是一种地球物理技术，其中电磁（EM）信号（类似于无线电波，但在地面上）在钻孔之间发送。这些电磁信号受到岩石类型以及钻孔之间是否存在矿化带的影响。因此，对一个井眼中发射器的多个位置和另一个井眼中接收器的多个位置进行RIM测量，可以提供信息，用于绘制井眼之间的任何矿化带，从而绘制矿体。然而，目前的计算机模拟和解释程序是基于一些重要的近似值。这些近似值使得RIM数据集的计算机建模相对较快。然而，这些近似也意味着建模和解释程序在绘制和描绘任何矿体的准确性和可靠性方面受到限制。这里提出的研究旨在产生建模和解释方法，这些方法不利用这些近似，而是考虑到地面上电磁信号的全部行为。我们将开发用于预测的计算数学和软件，考虑到完整的EM物理情况，将根据给定的假设模型测量钻孔之间的岩石类型和矿化的RIM数据。我们还将开发解释方法和软件，根据RIM数据集构建钻孔之间的岩石和矿化模型，即“反转”RIM数据。我们预计，我们将为RIM数据制定一个解释程序，将能够提供比目前可能的更准确、更可靠的结果。从RIM数据中获得更清晰、更可靠的地下图像，将使矿产勘探公司能够使用更少的钻孔来描绘和评估潜在的矿体。这降低了寻找和开发矿产资源的成本。这反过来又有助于矿产勘探行业的健康和竞争力，矿产勘探行业是纽芬兰和拉布拉多以及加拿大的重要财富创造者和就业提供者。

The radio imaging method (RIM) is a geophysical technique in which electromagnetic (EM) signals (similar to radio waves, but in the ground) are sent between boreholes. These EM signals are affected by the types of rocks, and whether or not there are zones of mineralization, between the boreholes. Making RIM measurements for many locations of the transmitter in one borehole and many locations of the receiver in the other borehole therefore provides information that could be used to map out any zones of mineralization, and hence ore bodies, between the boreholes. However, current computer modelling and interpretation procedures are based on some significant approximations. These approximations make the computer modelling of a RIM data-set relatively fast. However, these approximations also mean that the modelling and interpretation procedures are limited in how well and how reliably they can map and delineate any ore body. The research proposed here is intended to produce modelling and interpretation methods that do not make use of these approximations but rather take into account the full behaviour of the EM signals in the ground. We will develop the computational mathematics and software for predicting, taking into account the full EM physics of the situation, the RIM data that would be measured for a given hypothesized model of the rock types and mineralization between the boreholes. We will also develop interpretation methodology and software that constructs, from a RIM data-set, a model of the rocks and mineralization between the boreholes, i.e., "inverts" the RIM data. We anticipate that we shall produce an interpretation procedure for RIM data that will be able to provide more accurate and more reliable results than is currently possible. Obtaining a clearer, more reliable picture of the subsurface from RIM data will enable mineral exploration companies to use fewer boreholes to delineate and assess prospective ore bodies. This reduces the cost of finding and developing mineral resources. This in turn helps the health and competitiveness of the mineral exploration industry, which is a significant generator of wealth and provider of employment in Newfoundland and Labrador and in Canada.