JURASSIC OCEANIC GATEWAYS OF THE NORTH ATLANTIC

Jurassic rifting and breakup are still poorly understood in the North Atlantic region, particularly when considering
that large swathes of NW Europe record the development of proto-oceanic gateways as early as the Late Triassic-
Jurassic [1]. The first of these proto-oceanic gateways to form, and to effectively link the North and Central Atlantic
regions, was the Iberia- Newfoundland gateway with its prolongation towards Ireland and the North Sea.
Following widespread evaporite deposition in the Late Triassic-earliest Jurassic, marine strata were first deposited
during the Sinemurian in West Iberia. Black shales were episodically developed during the Pliensbachian-Toarcian and
again during Oxfordian-Kimmeridgian. Outcrop and borehole data provide information on these periods of basinal
deoxygenation in Iberia, Southern UK, and in extended areas of the Central North Sea [2]. However, an integrated
analysis of the petrophysical, geochemical and stratigraphic significance of 'North Atlantic' black shale events is still
to be undertaken to unravel the tectonic, climatic, and eustatic controls.
The project will use seismic, borehole and outcrop data from West Iberia, Canada, Southern UK and North Sea to
investigate the conditions in which Jurassic black shales were deposited. We aim to document at seismic, borehole
and outcrop scales the occurrence (and distribution) of these black shale events and to understand the main local and
regional controls on their generation, and at what time and length scales these operate. The student will interpret a
suite of 50+ boreholes from the region, tying stratigraphic, petrophysical and geochemical information to 2D and 3D
seismic data. In parallel, field analogues from the Lusitanian (Portugal) and Wessex Basins (England) will be
comprehensively studied and sampled. Data from these sites are necessary to correlate petrophysical, seismic and
geochemical data at different scales, and to document the stratigraphic architecture of black shales.
Training in seismic interpretation will be provided using state-of-the-art workstations. Following a recent upgrade,
Cardiff houses one of the most advanced seismic interpretation laboratories in Europe and the student will have
access to leading edge computational facilities, namely Schlumberger's Petrel, CGG-Veritas Hampson-Russell and
IKON Rock-Doc for petrophysical modelling and borehole analyses. IGI Ltd. will provide geochemical data and the
P:IGI software.