Characterisation of 3D Fracture Networks using Quantitative Outcrop Analogues Analysed with Lidar and Shallow Geophysics
Improving our understanding of flow of hydrocarbons and CO2 in fractured reservoirs requires detailed characterisation of three-dimensional fracture networks at seismic and sub-seismic scales. Terrestrial laser scanning (ground-based lidar) is a very rapid method to record the three-dimensional surface of outcrops, at centimetre resolution, with high spatial precision. Geological processing of the resultant lidar outcrop…
Read MoreQuantification of fold curvature and fracturing using terrestrial laser scanning
Terrestrial laser scanning is used to capture the geometry of three single folded bedding surfaces. The resulting light detection and ranging (LIDAR) point clouds are filtered and smoothed to enable meshing and calculation of principal curvatures. Fracture traces, picked from the LIDAR data, are used to calculate fracture densities. The rich data sets produced by…
Read MoreFracture Network Characteristics and Velocity Structure of a Seismic Fault Zone
Fault zone structure over a wide range of scales strongly influences earthquake mechanics. In this work we quantify the hierarchical structure, fracture network characteristics, and velocity structure of the seismic Gole Larghe Fault Zone (GLFZ) in the Italian Alps using a range of digital fieldwork techniques and experimental facilities. The GLFZ is c.500m thick and…
Read MoreQuantitative characterization of fracture networks using terrestrial lidar data, an example from high porosity sandstones at Appleby
Quantifying spatial variations in fracture orientations and fracture density with respect to position in a rock unit is an important part of the complete description of a 3D fracture network. We interpret terrestrial lidar data obtained from an outcrop of fractured Permo-Triassic aeolian red sandstone in the Vale of Eden half graben at George Gill,…
Read MoreCO2 Dissolution From Inclined Fractures in Deep Saline Formations
Supercritical CO2 injected into a deep saline formation will eventually dissolve in the formation waters. The density of formation waters increases with CO2 concentration and becomes negatively buoyant. In time convective instabilities could form and move CO2 downwards away from the caprock. This is favourable for carbon capture and storage as it reduces the risk…
Read MoreCharacterising Fracture Systems on the Isle of Lewis: An Onshore Analogue for the Clair Field
The Clair oil field lies offshore from western Shetland and is estimated to contain over 4 billion bbl. The basement here is composed of Lewisian-like rocks that are overlain by a reservoir of Devonian-Carboniferous sandstones and conglomerates of the Clair Group. Reservoir performance indicates that fractured basement rocks play a significant role in the resource…
Read More3D Modeling of Fracture Density and Connectivity Within Faulted Chalk Reservoirs – A Case Study From Flamborough Head, UK
The anisotropic distribution of fracture density and connectivity in 3D across a fault zone can exert a strong control on fluid flow. However, fracture density and connectivity values are usually estimated quantitatively using 1D and 2D fracture datasets, which do not take into account the aspect ratio of the individual fractures. In this study LiDAR…
Read MoreCharacterising Fault Networks in Three Dimensions in the Lewisian Gneiss Complex, NW Scotland: Implications for Petroleum Potential in the Clair Field Basement, Faroe-Shetland Basin
Fractured crystalline basement rocks are increasingly a target for hydrocarbon exploration in the development of existing fields. In the Clair field that lies 75km west of the Shetland Isles, the primary clastic reservoirs of Devonian and Carboniferous age overlie and onlap fractured Lewisian basement. Fractures in the basement are thought to play a significant role…
Read MoreComparison between faults extracted from seismic and Elastic Dislocation Modelling
Most fault enhancement techniques rely on enhancing the discontinuities within the seismic signal. However, there is a large variety of phenomena that cause discontinuities in the seismic signal. Furthermore, fault heaves are lower than the Fresnel zone width thus not fully resolvable and as a result, faults are often poorly imaged and can be blurry…
Read MoreCharacterising fracture systems on the Isle of Lewis: An onshore analogue for the Clair Field
Exotic hydrocarbon reservoirs such as crystalline basement are increasingly a target for hydrocarbon exploration in the development of new and existing fields. The Clair field lies in the Faroe-Shetland basin with reservoirs in Devonian and Carboniferous sediments that overlie and onlap a basement high that was up-faulted during the Mesozoic. At Clair the basement is…
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