Seismic geomorphology of submarine landslides in the Chalk Group of the Danish Central Graben:implications for reservoir potential

This study documents a variety of deposits created by submarine landslides within the Upper Cretaceous to lowermost Paleocene Chalk Group in the Danish Central Graben and investigates the impact of remo-bilization on porosity. Improved visualization of the landslides in 3D seismic data compared with previous studies was facilitated by better seismic data quality for the Chalk Group, the availability of a large stack of stratigraphy-consistent horizons and the use of spectral decomposition data. The illustrated examples are chosen to reflect the spectrum of deformation styles seen in the chalk and all have a well penetrating the affected suc-cession. They include a large collapse (375 km2) of an inversion ridge within the Kraka and Gorm formations, a field of large slide blocks (100–1000 m, 10–26 m) of likely lowermost Danian age embedded in the uppermost Ekofisk Formation, a debris flow system within the uppermost Tor Formation probably originating from the Ringkøbing–Fyn High and fine-grained bottom current sediment waves within the lowermost Danian Ekofisk Formation. In general, porosities are higher (10–25 porosity units) in the remobilized chalk compared with time-equivalent pelagic chalk in nearby reference wells. In earlier studies this has been linked to lack of bioturbation (resulting in limited grain repacking) in the remobilized chalks owing to high sedimentation rates, resulting in a relatively open fabric during initial burial. In contrast, surrounding and covering pelagic deposits could be much more effectively bioturbated, leading to tighter grain packing during burial. The insights of this study help in the seismic characterization of mud-grade carbonate oozes and have important applications in the reservoir modelling of mud-grade carbonate reservoirs (also in light of carbon capture and storage), and in palaeo-reconstructions of pelagic seafloors since submarine landslides provide kinematic indicators.</p

Search for a heavy Standard Model Higgs boson in the channel H→ZZ→l+l−qqˉH\rightarrow ZZ\rightarrow l^{+}l^{-} q\bar{q} using the ATLAS detector

A search for a heavy Standard Model Higgs boson decaying via H->ZZ->llqq, where l=e,mu, is presented. The search is performed using a data set of pp collisions at sqrt(s)=7 TeV, corresponding to an integrated luminosity of 1.04 fb^-1 collected in 2011 by the ATLAS detector at the CERN LHC collider. No significant excess of events above the estimated background is found. Upper limits at 95% confidence level on the production cross section (relative to that expected from the Standard Model) of a Higgs boson with a mass in the range between 200 and 600 GeV are derived. Within this mass range, there is at present insufficient sensitivity to exclude a Standard Model Higgs boson. For a Higgs boson with a mass of 360 GeV, where the sensitivity is maximal, the observed and expected cross section upper limits are factors of 1.7 and 2.7, respectively, larger than the Standard Model prediction.Comment: 11 pages plus author list (26 pages total), 4 figures, 1 table, final version to appear in Physics Letters