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[1] The Sea of Marmara is presently the site of pure dextral strike-slip faulting that connects the Izmit Fault in the east to the Ganos Fault in the west along a linear strike-slip fault that is part of the northwestern branch of the North Anatolian Fault. This active Main Marmara Fault (MMF) cuts across a succession of depocenters and highs. Analysis of a large data set that includes multichannel seismic lines, sparker and deep towed high definition seismics, shows that most of the N120[degrees]E trending normal faults framing these depocenters are now inactive as they are sealed by an average thickness of 300 m of sediments. The highs correspond to a series of NE-SW trending anticlines and reverse faults blanketed by a thin cover of undeformed sediments. We interpret these structures as inverted former transfer faults of the now inactive Sea of Marmara pull-apart system. Depocenters and highs are the relicts of a former pull-apart basins and transfer faults system that accommodated the North Anatolian Fault motion within the Sea of Marmara prior to the formation of the MMF. We propose that a relatively short (a few hundreds of thousands of years) period of basin inversion accompanied the localization of strain along the present Main Marmara Fault, until it was fully formed, 200 [+ or -] 100 Kyr ago. The preexisting pull-apart basin system accounts for about 30 km of motion along this fault system and thus probably appeared sometime in late Pliocene or early Pleistocene as a reactivated portion of the old Thrace basin. During the Plio-Quaternary the Sea of Marmara has been the site of progressive localization of strain. INDEX TERMS. 8107 Tectonophysics: Continental neotectonics; 8010 Structural Geology: Fractures and faults; 8122 Tectonophysics: Dynamics, gravity and tectonics; 8109 Tectonophysics: Continental tectonics--extensional (0905); KEYWORDS: Sea of Marmara, tectonics, geodynamics, strain localization, strike-slip fault, basin inversion.

The collision of India with Asia results in a rapidly changing stress pattern around both Himalayan syntaxes. The maximum compressive stress, which is north-south north of the indenter, fans radially through nearly 180 degrees around the syntaxes to accommodate the necessary strike-slip motion on the edges of the indenter. Thus, the whole Indochina Peninsula was swept by the migrating stress and associated strain pattern as the eastern syntaxis moved to the north. As a result, the maximum horizontal component of the stress field is predicted to have been first oriented east-west, then north-south. We propose that this changing stress field controlled the opening of the sedimentary basins and of the South China Sea as well as the direction of motion of the major strike-slip faults.

Summary: Investigation of niche specialization in microbial communities is important in assessing consequences of environmental change for ecosystem processes. Ammonia oxidizing bacteria (AOB) and archaea (AOA) present a convenient model for studying niche specialization. They coexist in most soils and effects of soil characteristics on their relative abundances have been studied extensively. This study integrated published information on the influence of temperature and pH on AOB and AOA into several hypotheses, generating predictions that were tested in soil microcosms. The influence of perturbations in temperature was determined in pH 4.5, 6 and 7.5 soils and perturbations in pH were investigated at 15°C, 25°C and 35°C. AO activities were determined by analysing changes in amoA gene and transcript abundances, stable isotope probing and nitrate production. Experimental data supported major predictions of the effects of temperature and pH, but with several significant discrepancies, some of which may have resulted from experimental limitations. The study also provided evidence for unpredicted activity of AOB in pH 4.5 soil. Other discrepancies highlighted important deficiencies in current knowledge, particularly lack of consideration of niche overlap and the need to consider combinations of factors when assessing the influence of environmental change on microbial communities and their activities. [ABSTRACT FROM AUTHOR]

The Black Sea is considered to be a Mesozoic–Early Cenozoic marginal basin related to the north-dipping subduction of Tethys beneath Europe. However deformation of this basin during the successive Eocene to Neogene collisions of African-derived continental fragments (Kirshehir and Arabian micro plates) remains poorly understood. A multi-channel seismic survey conducted in the central part of the Black Sea has shed light on the superimposed tectonic fabrics of the Central Ridge (the Mid Black Sea High, MBSH) in response to these successive collisions. The MBSH is formed by a series of large NW–SE trending anticlines and synclines, and possible northeast-verging thrusts were identified at the boundary with the deep East Black Sea Basin northeast of the ridge. These buried folds and thrusts, blanketed by 3 to 8 s TWT of undeformed sediments, are interpreted as the offshore extension of the Early Cenozoic tectonic belt resulting from the collision between the Pontides in the north and the Kirshehir block to the south. The offshore part of the belt forming the ridge could have then collapsed when collision ended. Neogene structures also affect the MBSH. A recent graben (the Sinop Trough) extends between this central high and mainland Turkey. This graben could have been formed during the late Miocene incipient dextral strike slip motion of the North Anatolian Fault that was initiated during extrusion of the Anatolian microplate. Active tectonic inversion of deep-seated normal faults present along the Pontides passive margin was also observed along the northeastern flank of the Eastern Pontides. This deformation is the westernmost extension of the Lesser Caucasus front that outlines the suturing of the Eastern Black Sea Basin in easternmost Turkey and in Georgia. [Copyright &y& Elsevier]

Focuses on the boundary of the Philippine Sea Plate and eastern Indonesia corresponds to a wide deformation zone that includes the stretched continental margin of Sundalan. Evaluation of relative motion in tectonic boundaries; Discussion of the kinematic pattern in Global Positioning System; Establishment of simple model on the pattern of transfer.

Presents a report from the Leg 124 shipboard scientific party in the western Pacific Ocean. Compositions of marginal basins.