Quantitative 3D remote digital compositional and structural characterisation of outcrops

陆上盆地三维地下地理空间模型的构建是油气勘探的一个重要方面，并且严重依赖于从地质露头和钻孔岩心分析中获得的信息。目前的分析技术产生非常有限的数据集，不能完全捕获这些地质特征的固有3D性质，这导致结构信息中的显著差距，从而严重影响地质解释的准确性。一种新开发的野外便携式成像仪器（MicroFTS）已证明能够精确地远程识别关键沉积岩性。该项目将证明MicroFTS能够以极低的成本显著增加样品-钻孔-现场和盆地尺度的结构和成分信息的数量、覆盖范围和详细程度。地质露头为地质学家提供了重要的主要数据来源，并在学术界和工业界广泛用于教学、培训和研究。以及开发概念性和预测性地质模型。准确描述岩石体积中的岩性和矿物学特征以及油气盆地的沉积结构对于预测油气资源的存在或量化油气资源的体积是至关重要的。地震反射数据可以对大规模储层结构成像，但垂直和水平分辨率通常限于数十米。相反，岩心和电缆测井可提供高得多的分辨率，但威尔斯井通常分布稀疏，仅对岩石体积的很小百分比进行采样。然而，露头提供了对岩体及其几何形状、结构和岩性不均匀性的直接观测，范围从不到1厘米到几十公里。传统的露头分析技术（如沉积测井、地表地质图和剖面图）提供了有关地质系统的宝贵信息，促进了许多当代构造和地层分析和综合。然而，野外数据通常是通过一维和二维纸质方法收集的，这些方法不能完全捕捉地质特征固有的3D性质。相关的准确度、精确度和不确定性很少定义，而且往往难以提取关于沉积岩体几何形状和空间不均匀性的可靠定量信息，而这些数据对于基于计算机的三维地质统计储层建模至关重要。然而，可访问性问题大大限制了使用传统制图方法从这些网站获得的数据。地质暴露也可能超过数十平方公里，导致数据集严重采样不足和不具代表性。使用钻孔岩心和露头的定量、数字化表征来分析沉积结构的更加综合的方法将提高盆地分析的准确性。虽然使用陆地激光雷达扫描（TLS）在远程模拟地质界面几何形状的准确性方面取得了重大进展，岩石体积本身的定义受到可使用照片检索的矿物学和岩性学信息的范围和准确性的严重限制的限制。虽然基于光谱反射率的遥感方法已证明在分辨岩石成分方面具有一定的能力，但由于可探测矿物的范围和准确性有限，以及观测配置和照明条件的影响，业务效用受到严重限制。因此，迫切需要一种方法，可以远程探测石油和天然气部门感兴趣的岩性。发射光谱学具有许多可以满足这一要求的能力。

The construction of 3D sub-surface geospatial models of onshore basins is a vital aspect of hydrocarbon exploration and is critically dependant on the information derived from the analysis of geological outcrops and borehole cores. Current analysis techniques produce very limited datasets that do not fully capture the inherent 3D nature of these geological features which result in significant gaps in structural information with consequent severe effects on the accuracy of geological interpretation. A newly developed field portable imaging instrument (MicroFTS) has demonstrated the capability to remotely identify the key sedimentary lithologies accurately. This project will demonstrate the capability of the MicroFTS to significantly increase the volume, coverage, and level of detail, of structural and compositional information at sample-borehole-site and basin scales, at very low cost.Geological outcrops provide an important primary source of data for geologists and are extensively used within both academia and industry for teaching, training and research, and for the development of conceptual and predictive geological models. Accurate characterisation of lithology and mineralogy in rock volumes and the sedimentary architecture of a hydrocarbon basin is central to predicting the presence or quantifying the volumetrics of hydrocarbon resources. Seismic reflection data can image large-scale reservoir architectures but vertical and horizontal resolution is typically limited to tens of metres. Conversely, core and wireline logs can provide much higher resolution but wells are typically sparsely distributed, sampling only a very small percentage of the rock volume. Outcrops, however, offer direct observations of rock bodies and their geometries, architecture and lithological heterogeneities over scales ranging from less than 1 cm to several tens of kilometres. Conventional outcrop analysis techniques (e.g. sedimentary logs, surface geological maps and cross-sections provide invaluable information on geological systems, facilitating many contemporary structural and stratigraphical and syntheses.However, field data are typically collected by one- and two dimensional paper-based methods that do not fully capture the inherent 3D nature of geological features. Associated accuracy, precision and uncertainty are rarely defined, and it is often difficult to extract reliable quantitative information on the geometries and spatial heterogeneities of sedimentary rock bodies, data which are essential for 3D computer-based geostatistical reservoir modelling. However accessibility issues significantly limit the data acquired from such sites using traditional mapping methods. Geological exposures can also extend over 10s of square kilometres, resulting in a significantly under sampled and unrepresentative dataset. A more integrated approach to the analysis of the sedimentary architecture using a quantitative, digital- based characterisation of borehole cores and outcrops would enhance the accuracy of basin analysis.Although there have been significant advances in the accuracy of modelling the geometry of geological interfaces remotely using Terrestrial LiDAR Scanning (TLS), the definition of the rock volume itself has been restricted by severe limitations in the range and accuracy of the mineralogical and lithological information retrievable using photographs. While spectral reflectance based remote sensing methods have demonstrated some capabilities in resolving rock compositions the operational utility is severely restricted by the limited range and accuracy of minerals that can be detected and the effects of viewing configuration and illumination conditions. There is therefore an urgent requirement for a methodology that can remotely characterise the lithologies of interest to the oil and gas sector. Emission spectroscopy has a number of capabilities that can meet this requirement.