SENGER K.

Closely spaced, sub-parallel fracture networks contained within localized tabular zones that are fracture corridors may compromise top seal integrity and form pathways for vertical fluid flow between reservoirs at different stratigraphic levels. This geometry is exemplified by fracture corridors found in outcrops of the Jurassic Entrada...

We discuss discrete zones of enhanced fracturing characterized by closely-spaced, sub-parallel fracture networks (i.e. fracture corridors) as preferential fluid flow pathways which serve to bypass sealing systems and to connect reservoirs at different stratigraphic levels. We identify 3 types of fracture corridors on the basis of their...

Late Mesozoic mafic igneous rocks are widespread across the Arctic region, and are collectively referred to as the High Arctic Large Igneous Province (HALIP). In Svalbard the HALIP is represented by the Diabasodden Suite, an extensive system of predominantly basic intrusive doleritic rocks. Associated lava flows are exposed on the far east of...

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This baseline study on fracture populations affecting the Mesozoic sedimentary succession of central Spitsbergen (Svalbard) has been performed to characterize the reservoir-caprock system explored for potential subsurface CO2 storage by the Longyearbyen CO2 Lab project. Integrating structural and stratigraphie analyses of outcrop and borehole...

Both thermogenic and biogenic gas were encountered during scientific drilling on Svalbard, Arctic Norway. The thermogenic gas has been encountered in an interval at 650-703 m depth, spanning both the lower part of the caprock, an organic-rich shale unit with subordinate siltstone intervals, and the upper part of the siliciclastic reservoir...

We present a geological model of an unconventional siliciclastic reservoir projected for CO2 sequestration near Longyearbyen, Svalbard. The reservoir is characterized by a substantial sub-hydrostatic pressure regime, very low matrix porosity and -permeability values, extensive natural fracturing and the presence of igneous dykes and sills. Due...

The target siliciclastic aquifer investigated by the Longyearbyen CO2 Lab as a possible test-scale CO2 storage unit is a dual-permeability reservoir characterized by fractured, tight lithologies. By integrating borehole and outcrop data, the reservoir section has been subdivided in intervals defined by 5 lithostructural units (LSUs), each one...

Storage capacity is a key aspect when validating potential CO2 sequestration sites. Most CO2 storage projects, for obvious reasons, target conventional aquifers (e.g., saline aquifers, depleted hydrocarbon fields) with good reservoir properties and ample subsurface data. However, non-geological factors, such as proximity to the CO2 source, may...

Structure-from-motion (SfM) photogrammetry enables the cost-effective digital characterisation of seismic- to sub-decimetre-scale geoscientific samples. The technique is commonly used for the characterisation of outcrops, fracture mapping, and increasingly so for the quantification of deformation during geotechnical stress tests. We here apply...

Structure-from-motion (SfM) photogrammetry has become an important tool for the digitalisation of outcrops as digital outcrop models (DOMs). DOMs facilitate the mapping of stratigraphy and discontinuous structures like folds, faults, and fractures from the centimetre to kilometre scale. With pristine, treeless exposures, the outcropping strata...

Marine controlled source electromagnetic (CSEM) data have been utilized in the past decade during petroleum exploration of the Barents Shelf, particularly for de-risking the highly porous sandstone reservoirs of the Upper Triassic to Middle Jurassic Realgrunnen Subgroup. In this contribution we compare the resistivity response from CSEM data to...

Cooling fracture orientations in diabase sills associated with the Cretaceous High Arctic Large Igneous Province and syn-sedimentary Triassic faults help constrain a model for Svalbard's (NE Barents Shelf) Mesozoic stress field evolution. Fracture data from Edgeøya and adjacent islands in SE Svalbard, from S Spitsbergen, and from literature...

Igneous intrusions act as both carriers and barriers to subsurface fluid flow and are therefore expected to significantly influence the distribution and migration of groundwater and hydrocarbons in volcanic basins. Given the low matrix permeability of igneous rocks, the effective permeability in- and around intrusions is intimately linked to...