Detrital zircon age constraints on the provenance of sandstones on Hatton Bank and Edoras Bank, NE Atlantic

U-Pb dating of detrital zircons shows that the provenance of Cretaceous-Palaeogene sandstones on Hatton and Edoras banks (SW Rockall Plateau) comprises magmatic rocks dated at c. 1800 Ma and c. 1750 Ma respectively. Their depositional setting, first-cycle mineralogy and unimodal nature detrital zircon populations suggest these sandstones are of local origin. The zircon age data are therefore considered to provide constraints on these poorly-understood areas of the Rockall Plateau. The U-Pb dates are directly comparable with U-Pb zircon crystallisation ages from granitoid rocks reported from the Ketilidian Belt of southern Greenland and from the Rhinns Complex of western Britain. Hf isotopic data from the Edoras Bank sample are consistent with derivation from a juvenile Palaeoproterozoic block. In conjunction with previously reported Sm-Nd TDM model ages from the Ketilidian Belt, Rockall Bank and the Rhinns Complex, these data extend the known distribution of a large juvenile Palaeoproterozoic terrane spanning the southern NE Atlantic. By contrast, Hf isotopic data from the Hatton Bank sample imply a large contribution from Archaean crust. The zircon population from Edoras Bank also contains sparse Mesoproterozoic grains, providing evidence for the presence of volumetrically minor Grenville-age intrusions in the southern part of the Rockall Plateau

Kilometre-scale polygonal seabed depressions in the Hatton Basin, NE Atlantic Ocean: constraints on the origin of polygonal faulting

Polygonal faulting is a widespread phenomenon in sedimentary basins worldwide. It changes basin-scale fluid flow patterns and alters the physical properties of the sediments making it important for hydrocarbon exploration and geohazard analysis. It is generally accepted that polygonal fault patterns derive from dewatering and compaction of the host sediments, but there is debate regarding the processes that control polygonal faulting. New multibeam-bathymetry data from the Hatton Basin, NE Atlantic, show up to 10 m deep and 200–600 m wide troughs at the seabed. They connect to each other forming polygons that are several hundred metres across, i.e. of similar size as buried polygonal fault systems observed in 3D seismic data. The troughs are symmetrical and resemble elongated pockmarks. Previously unpublished high-resolution 2D seismic data from the same area show seismic disturbance zones similar to pipes observed under pockmarks elsewhere as well as faults that have all the characteristics of polygonal fault systems. The observation of the wide disturbance zones is enigmatic, as they appear to follow the polygonal seafloor pattern. The observed extent of the polygonal sediment contraction system is substantial covering almost 37,000 km2. We calculate that some 2600 km3 of possibly carbon-bearing fluids have been expelled from this system and we expect that this will affect the benthic ecosystems, although so far there is only limited evidence for chemosynthetic habitats

Hermeneutics of Self as a Research Approach

Circumstances shaped the decision to engage in a hermeneutics of self. In contrast to a common research approach, the researcher became the participant. The purpose of the research was to reveal interpretive meaning of that experience toward the view of becoming a global coworker. Philosophical insights informing the methodological approach and the analysis were drawn from Heidegger, Gadamer, and theological authors. Twelve people drawn from a variety of backgrounds were invited to interview the researcher following a 3-week field visit to explore HIV/AIDs in Malawi. Interviews were transcribed and analysis achieved through THREADs: Thinking Hermeneutically and Reflecting through the Experience, Asking questions while Dwelling in the everyday. For the researcher the experience was at times painful but deeply rewarding. The insights that emerged provide a mirror through which intending global coworkers can consider their own assumptions, values, and motivations. Such an approach is worthy of adding to the research repertoire

Evidence for current-controlled morphology along the western slope of Hatton Bank (Rockall Plateau, NE Atlantic Ocean)

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