Studies of fracture network geometry of reservoir outcrop analogues from terrestrial lidar data: attempts to quantify spatial variations of fracture characteristics
We describe studies analysing terrestrial lidar datasets of fracture systems from a range of reservoir analogues in clastic and carbonate lithologies that represent geological analogues of offshore hydrocarbon reservoirs for the UK continental shelf. As fracture networks (observed here from centimetre to kilometre scale) can significantly affect the permeability of a fractured reservoir, the definition…
Read MoreMulti-scale characterization of the seismogenic Gole Larghe Fault Zone (Southern Alps, Italy): methodology and results
The Gole Larghe Fault Zone (GLFZ) in the Italian Southern Alps is characterized by the occurrence of cataclasites and pseudotachylytes (solidified frictional melts) formed along pre-existing magmatic cooling joints over a fault zone width of ca. 500 m, under ambient conditions of 9-11 km depth and 250-300C (the base of the seismogenic zone in the…
Read MoreStrain compatibility and fault linkage in relay zones on normal faults
Relay zones on normal faults are unlikely to have tabular geometries as depicted in idealised models. Rotation of a relay ramp between non-parallel and non-planar relay-bounding faults will inevitably lead to strain compatibility problems causing open gaps or overlaps within the relay zone. Linkage of relay-bounding faults does not evolve from a single branch point.…
Read MoreCharacterising fracture systems within the Lewisian Gneiss Complex, northwest Scotland: An onshore analogue for the Clair Field.
The Clair Field lies in the Faroe-Shetland Basin, with reservoirs in Devonian and Carboniferous sediments overlying and onlapping a basement high that was upfaulted in the Mesozoic. At Clair, the basement is considered an important control on fluid flow and structural development of the field due to its highly fractured nature. Consequently, it is important…
Read MoreCharacterising fracture systems within fractured crystalline reservoirs: the Lewisian Gneiss Complex, Scotland as an onshore analogue for the Clair Field basement
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- Carboniferous clastics overlying and onlapping a basement high that was upfaulted in the Mesozoic. This basement is known to control fluid…
Read MoreGeological controls on fault relay zone scaling
The overlap and separation distances of relay zones follow a power-law scaling relationship over nearly 8 orders of magnitude. Approximately one order of magnitude scatter in both separation and overlap exists at all scales. The strong power-law relationship (R2 = 0.98) suggests that the primary control on relay aspect ratio (overlap/separation) is a scale-invariant process,…
Read MoreCharacterisation 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 MoreCombining GPR and Terrestrial LiDAR to Produce 3D Virtual Outcrop Models
Terrestrial LiDAR provides high-resolution outcrop data in 2.5D to provide quantitative reservoir analogues through the interpretation of structural geometries and sedimentological architectures within the outcrop at sub-centimeter scale. The resulting interpretation is used to provide a qualitative check on the validity of reservoir models. However, without subsurface information geological surfaces and features are usually extrapolated…
Read MoreExtending digital outcrop geology into the subsurface
Digital survey methods, including terrestrial laser scanning (lidar) and differential GPS, allow geological and topographic data from outcrops to be recorded very rapidly, in 3D, at detailed resolutions and with high spatial precision. Geological interpretations of outcrop datasets (e.g., fault or bedding traces) can be extended into the subsurface using geometric, probabilistic, or deterministic methods.…
Read MoreExperimental insights on geomorphological processes within dam break outburst floods
Hydraulic behavior and unsteady sediment transport within dam break outburst floods are inherently inter-dependent, yet poorly constrained. This study experimentally determined how the mobility and clast size of channel bed sediments affected the peak flow depth and flow velocities, wave propagation and attenuation, sediment entrainment and duration of transport, flood power, energy transfer and geomorphological…
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