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Collin, United States

Csato I.,Collin College | Granjeon D.,French Institute of Petroleum | Catuneanu O.,University of Alberta | Baum G.R.,G.R. Baum and Associates LLC
Basin Research | Year: 2013

A three-dimensional quantitative stratigraphic forward model is employed to investigate the controls leading to the Messinian events in the lacustrine Pannonian Basin of Central Paratethys, and the link between the Messinian salinity crisis in the Mediterranean and the late Miocene-Pliocene stratigraphy of the Pannonian Basin. Subsurface geological data show that a prominent unconformity surface formed during Messinian time in the Pannonian Basin associated with a sudden forced regression, abrupt basinward shift of facies and a subsequent, prolonged lowstand normal regression. The lowstand prograding series filled up the shallow basin fast, while, at the same time, the marginal areas of the basin were subject to tectonic inversion. The Dionisos program used in this research is built on a nonlinear water-driven sediment diffusion process, and it employs multiple sediment classes, basin flexure and compaction. Four different scenarios were built in the experiments to test possible basin histories with different rates and timing of tectonic inversion. Each scenario was modelled in two versions: including and not including a lake-level fall in the Messinian. The results confirm that the Pannonian Basin in the study area has undergone a tectonic inversion since the Messinian, although the exact rates of uplift at different locations remain uncertain. The unconformity and the observed stratigraphic architecture and facies pattern could be modelled adequately only in the versions that applied a Messinian lake-level fall. Our research concludes that the Messinian unconformity in the Pannonian Basin was caused by an absolute lake-level drop, likely linked to the desiccation of the Mediterranean, followed by subsidence and normal regression in the basin centre and concomitant tectonic inversion and uplift along the basin margins. © 2012 Blackwell Publishing Ltd, European Association of Geoscientists & Engineers and International Association of Sedimentologists.

Gvirtzman Z.,Geological Survey of Israel | Csato I.,Collin College | Granjeon D.,French Institute of Petroleum
Marine Geology | Year: 2014

The recent world-class gas discoveries in Early Miocene sand units offshore Israel raises the question of their origin. Apparently, the simplest explanation is to relate them to a fluvial system that arrived from Arabia at that time. This system predated the modern (Pliocene) Nile River supply and existed until captured by the Dead Sea valley. Interestingly, however, very little sedimentation occurred along the Levant continental margin before the Pliocene in spite of its stepped structure that provided much space for accommodation. The only way that sediments could have bypassed the continental margin and arrive at the deep basin without being trapped in the middle is through submarine channels that crossed the continental margin. Here we explore this possibility using 3-D stratigraphic modeling techniques that quantify the sediment load and the water discharge required to fill the basin by pushing enough sediment through submarine channels. We show that such a scenario requires a fluvial system in the order of the largest rivers that exist today on earth in terms of drainage area and water discharge. Alternatively, it requires extreme hydraulic conditions in terms of diffusion coefficients and an elevated drainage basin that could not have existed in the study area. We therefore challenge the traditional view of Arabia as the main source for Oligo-Miocene deposits in the Levant Basin and suggest that the basin was mainly fed by a proto-Nile system that transported clastic material to the North African margin and then farther east by ocean currents. In a wider view we demonstrate how numerical modeling can constrain sediment transport through submarine channels as a function of basin geometry and hydraulic conditions, and how paleogeographic knowledge can be combined with current data on world rivers to evaluate if modeling results are plausible. © 2013 Elsevier B.V.

Lombricine kinase is an annelid enzyme that belongs to the phosphagen kinase family of which creatine kinase and arginine kinase are the typical representatives. The enzymes play important roles in the cellular energy metabolism of animals. Biochemical, physiological and molecular information with respect to lombricine kinase is limited compared to other phosphagen kinases. This study presents data on the cDNA sequences of lombricine kinase from two smaller oligochaetes, Enchytraeus sp. and Stylaria sp. The deduced amino acid sequences are analyzed and compared with other selected phosphagen kinases. The intron/exon structure of the lombricine kinase gene was determined for these two species as well as two additional oligochaetes, Lumbriculus variegatus and Tubifex tubifex, and compared with available data for annelid phosphagen kinases. The data indicate the existence of a variable organization of the proposed 8-intron/9-exon gene structure. The results provide further insights in the evolution and position of these enzymes within the phosphagen kinase family. © 2012 Elsevier B.V.

Yang C.,University of North Texas | Arvapally R.K.,University of North Texas | Tekarli S.M.,University of North Texas | Tekarli S.M.,Collin College | And 5 more authors.
Angewandte Chemie - International Edition | Year: 2015

The trinuclear triangle-shaped system [tris{3,5-bis(heptafluoropropyl)-1,2,4-triazolatosilver(I)}] (1) and the multi-armed square-shaped metalloporphyrin PtOEP or the free porphyrin base H2OEP serve as excellent octopus hosts (OEP=2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphine). Coupling of the fluorous/organic molecular octopi 1 and H2OEP or PtOEP by strong quadrupole-quadrupole and metal-π interactions affords the supramolecular assemblies [1·PtOEP] or [1·H2OEP] (2 a), which feature nanoscopic cavities surrounding the upper triangular and lower square cores. The fluorous/organic biphasic configuration of [1·PtOEP] leads to an increase in the phosphorescence of PtOEP under ambient conditions. Guest molecules can be included in the biphasic double-octopus assembly in three different site-selective modes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Csato I.,Collin College | Catuneanu O.,University of Alberta
Stratigraphy | Year: 2012

Systems tracts are linkages of contemporaneous depositional systems that accumulate under specific conditions of accommodation and sediment supply. They are identified by their stratal stacking pattern and position within the sequence. In practice, it is often difficult to assign accurately relative sea-level position to stacking patterns. Observations also show that systems tracts may succeed each other in different orders, not necessarily according to the prediction of an ideal model. The purpose of this study is to analyze the quantitative conditions for different possible combinations of systems tractswithin a cycle of relative sea-level change. Icehouse and greenhouse eustatic trends, active and passive tectonics, and varying depositional rates are considered as conditions. The systems tracts were defined based on the rate of accommodation change and depositional rate.Our quantitative calculations revealed that if the tectonics is active and the basement motion-time curve is segmented with sharp turning points between segments, eight possible successions of systems tracts may occur. If the basement motion is transitional between segments of subsidence and uplift, six scenarios are possible. Only three possible combinations of systems tracts can form in a sea-level cycle if the basement tectonics is passive. Variable depositional rate alone can be responsible for four different combinations of systems tracts under similar accommodation conditions. These combinations of systems tracts may occur primarily in greenhouse world. Eustasy under icehouse climatic conditions has rapid rates of change (up to 4000 m/myr), which are likelymany times faster thanwhat subsidence/uplift rates realistically can reach.As a consequence, only the full series of systems tract in the order of forced regression-lowstand normal regression-transgression-highstand normal regression can be predicted in icehouse, although the thickness of systems tracts in the real rock record may be rather small because of the fast rate of sea-level change.

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