Reassessment of the Bivalvia (Mollusca) from the Boom Formation (Rupelian, Oligocene) of Belgium, with description of new species

The bivalve species found in the Boom Formation (Rupelian, Early Oligocene) in Belgium are taxonomically revised. The distribution of the species over the Members and beds of this Formation is detailed. Of the 39 species occurring in the Boom Formation, 11 are recorded for the first time in Belgium, four of which are new to science: Semierycina (Semierycina) kruibekensis nov. sp., Scacchia (Scacchia) dufraingi nov. sp., Thracia (Thracia) vanremoorteli nov. sp. and Cardiomya (sensu lato) annamariae nov. sp. The large majority of the species seems to be endemic to the North Sea Basin. It is attemped to link the distribution of the species to ecological conditions (especially bathymetry) of the different beds

Ecology and evolution of Pliocene bivalves from the Antwerp Basin

The dock construction works in the port of Antwerp at Doel and Kallo (prov. Oost-Vlaanderen, Belgium) have allowed the collection of a rich and diverse Pliocene bivalve fauna. It contains 182 taxa, 178 species and four subspecies. 90 species out of 178 (51%) are extinct. The rate of extinction does not significantly vary between the recognised strata, ranging from Lower to Upper Pliocene. The average longevity of the species is calculated at 10.7 Ma. This long range makes most of these bivalve species unfit for use in Neogene stratigraphy. The bathymetry of the different levels of the Pliocene is assessed, using the species still occurring in the Recent fauna (49% of the total number): it decreases towards the end of the Pliocene

The family Triphoridae in the Neogene of Belgium (Mollusca, Gastropoda)

The taxonomy of the Neogene Triphoridae of Belgium is revised. From the Pliocene, the species Marshallora adverse (MONTAGU, 1803), Triphora radiospirata sp. nov., Triphora antwerpiensis sp. nov., Obesula scaldensis sp. nov., Norephora pliocaenica sp. nov., Subuliphora fritschi (von KOENEN, 1882), Inella vandermarki sp. nov., and Metaxia metaxae (DELLE CHIAJE, 1828) are described from the Kattendijk Formation and the Luchtbal and Oorderen Sand Members. Three Miocene species are studied: Subuliphora fritschi (von KOENEN, 1882), Triphora borealis KAUTSKY, 1925 and Metaxia degrangei (COSSMANN & PEYROT, 1922)

Gaps between jets in double-Pomeron-exchange processes at the LHC

The possibility to measure jet-gap-jet final states in double-Pomeron-exchange events at the LHC is presented. In the context of the ATLAS experiment with additional forward physics detectors, cross sections for different experimental settings and gap definitions are estimated. This is done in the framework of the Forward Physics Monte Carlo interfaced with a perturbative QCD model that successfully reproduces standard jet-gap-jet cross sections at the Tevatron. The extrapolation to LHC energies follows from the Balitsky-Fadin-Kuraev-Lipatov dynamics, implemented in the model at next-to-leading logarithmic accuracy.Comment: 8 pages, 5 figures, version to appear in PR

Next-leading BFKL effects in forward-jet production at HERA

We show that next-leading logarithmic (NLL) Balitsky-Fadin-Kuraev-Lipatov (BFKL) effects can be tested by the forward-jet cross sections recently measured at HERA. For d\sigma/dx, the NLL corrections are small which confirms the stability of the BFKL description. The triple differential cross section d\sigma/dxdk_T^2dQ^2 is sensitive to NLL effects and opens the way for an experimental test of the full BFKL theoretical framework at NLL accuracy.Comment: 5 pages, 4 figures, NLL-BFKL saddle-point approximation now compared with exact integration, version to appear in PL

Testing saturation with diffractive jet production in deep inelastic scattering

We analyse the dissociation of a photon in diffractive deep inelastic scattering in the kinematic regime where the diffractive mass is much bigger than the photon virtuality. We consider the dominant q\bar{q}g component keeping track of the transverse momentum of the gluon which can be measured as a final-state jet. We show that the diffractive gluon-jet production cross-section is strongly sensitive to unitarity constraints. In particular, in a model with parton saturation, this cross-section is sensitive to the scale at which unitarity effects become important, the saturation scale. We argue that the measurement of diffractive jets at HERA in the limit of high diffractive mass can provide useful information on the saturation regime of QCD.Comment: 12 pages, 5 figures, misprints corrected, published versio

QCD traveling waves at non-asymptotic energies

Using consistent truncations of the BFKL kernel, we derive analytical traveling-wave solutions of the Balitsky-Kovchegov saturation equation for both fixed and running coupling. A universal parametrization of the ``interior'' of the wave front is obtained and compares well with numerical simulations of the original Balitsky-Kovchegov equation, even at non-asymptotic energies. Using this universal parametrization, we find evidence for a traveling-wave pattern of the dipole amplitude determined from the gluon distribution extracted from deep inelastic scattering data.Comment: 10 pages, 5 figures, minor revision, version to appear in PL

Stratigraphy of an Early-Middle Miocene sequence near Antwerp in northern Belgium (southern North Sea Basin)

The lithostratigraphy and biostratigraphy of a temporary outcrop in the Antwerp area is described. The deposits can be attributed to the Kiel Sands and the Antwerpen Sands members, both belonging to the Lower and Middle Miocene Berchem Formation. Invertebrate and vertebrate macrofossils are abundantly present. The molluscan fauna compares well to former findings in the Antwerpen Sands Member. It can be concluded that the studied sequence is continuously present in the Antwerp area, and thickens in a northward direction. The study of the marine mammal fauna shows that eurhinodelphinids are the most common fossil odontocete (toothed-bearing cetaceans) in the Antwerpen Sands Member, associated here with kentriodontine, physeteroid, squalodontid, mysticete (baleen whales) and pinniped (seals) fragmentary remains. Both the molluscan fauna and the organic-walled palynomorphs indicate for the Antwerpen Sands Member deposition in a neritic, energetic environment, which shallowed upwards. The dinoflagellate cysts indicate that the Antwerpen Sands Member was deposited during late Burdigalian to Langhian times