A single-stage megaflood at the termination of the Messinian salinity crisis: Geophysical and modelling evidence from the eastern Mediterranean Basin

Highlights • We analyse seismic stratigraphy of post-Messinian succession in west Ionian Basin. • Termination of Messinian salinity crisis consisted of a single-stage Zanclean flood. • Megaflood followed a sea level drawdown of 1900 m in eastern Mediterranean. • Fine, well-sorted sediments are predicted in the thicker sections of flood deposit. • NW Ionian Basin hosts evidence of episodic slope instability after 1.8 Ma. Abstract The Messinian salinity crisis was an extraordinary event that resulted in the deposition of kilometre-thick evaporite sequences in the Mediterranean Sea after the latter became disconnected from the world's oceans. The return to fully and stable marine conditions at the end of the crisis is still subject to debate. Three main hypotheses, based on geophysical and borehole data, onshore outcrops and climate simulations, have been put forward. These include a single-stage catastrophic flood, a two-step reflooding scenario, and an overspill of Paratethyan water followed by Atlantic inflow. In this study, two research questions are addressed: (i) Which event marked the termination of the Messinian salinity crisis? (ii) What was the sea level in the eastern Mediterranean Sea during this event? Geophysical data from the western Ionian Basin are integrated with numerical simulations to infer that the termination of the crisis consisted of a single-stage megaflood following a sea level drawdown of 1900 m. This megaflood deposited an extensive sedimentary body with a chaotic to transparent seismic signature at the base of the Malta Escarpment. Fine, well-sorted sediments are predicted to have been deposited within the thicker sections of the flood deposit, whereas a more variable distribution of coarser sediments is expected elsewhere. The north-western Ionian Basin hosts evidence of episodic post-Messinian salinity crisis slope instability events in the last ~1.8 Ma. The largest of these emplaced a >200 km3 deposit and is associated with failure of the head of Noto Canyon (offshore SE Sicily). Apart from unravelling the final phase of the Messinian salinity crisis and the ensuing stratigraphic evolution of the western Ionian Basin, our results are also relevant to better understand megafloods, which are some of the most catastrophic geological processes on Earth and Mars

SOME PRODUCTION AND NUTRITION PARAMETERS IN VARIOUS SYSTEMS OF COW KEEPING IN EARLY LACTATION

Analizirani su proizvodni pokazatelji i utrošak hrane po jedinici proizvoda u dvije grupe od po 26 grla muznih krava, holštajn-frizijske pasmine koje su se telile u siječnju 1989. godine. Ispitivanja su vršena na farmi slobodnog sistema držanja, kapaciteta 1000 grla s instaliranom kompjuterskom opremom za rukovođenje procesima proizvodnje. Životinje su praćene od telenja do 35. dana laktacije. Ogledna grupa je od 6. dana laktacije bila u slobodnom sistemu držanja, dok je kontrolna grupa bila tokom čitavog trajanja ogleda u klasičnoj staji na vezu. Željelo se ustanoviti mogućnost uvoda krava u mlječnost u slobodnom sistemu držanja s hranidbom koncentrata preko automatskih hranilica i mužnjom u izmuzištu, sa automatikom za individualno praćenje proizvodnje. Ustanovljeno je da kompjuterski sistem omogućava uvod krava u mlječnost u slobodnom sistemu držanja,bez negativnih posljedica na proizvodnju, te da se ostvaruje utrošak hrane po jedinici proizvoda isti kao u klasičnoj staji na vezu.Production indicators and food consumption per product unit in two groups of 26 Holstein-Frisian dairy cows calved in January 1989 were analyzed. Investigations were carried out on a free system dairy farm, capacity a 1000 head, with a computer installed to follow\u27 the production processes. The cows were followed from calčvng until 35- day of lactation. The trial group was kept free from the 6rh lactation day hile the control group was kept tied in a traditional shed during the trial period. The aim was to establish a possibility of introducing the cows to being milked in a free system and fed on concentrates by means of automatic feeding system and milked in the milking parlour; each animal as followed by the computer system. It as established that the computer system enabled initiations of cows into milking in the free keeping system without negative effects on production and that the food consumption per production unit as the same as when the cows were kept tied in a traditional shed

A STEP fault in Central Betics, associated with lateral lithospheric tearing at the northern edge of the Gibraltar arc subduction system

We study the crustal and lithospheric mantle structure under central Betics in the westernmost Mediterranean region by migrating P-receiver functions along a dense seismic profile (∼2 km interstation distance). The profile, North–South oriented, probes the crustal structure of different geological units, from the Alboran domain in the south with metamorphic rocks, through the External Zones with sedimentary rocks to the Variscan terrains of the Iberian Massif in the north. From north to south, the Moho depth increases from ∼30 km to ∼46 km underneath the Guadix basin, due to the underthrusting of the Iberian crust below the Alboran crust, and suddenly shallows to ∼30 km underneath the Internal Zones with a step of 17 km. This sharp Moho step correlates well with a lithospheric step of ∼40 km, where the thickness of the lithosphere changes abruptly from ∼100 km in the north to ∼50 km in the south. We interpret this sharp and prominent lithospheric step as the termination of the Iberian lithosphere caused by a near-vertical STEP (Subduction-Transform-Edge-Propagator) fault that continues towards the surface as a positive flower tectonic structure of crustal scale. This STEP fault is located at the northern edge of the narrow Westernmost Mediterranean subduction system facilitating the slab rollback motion towards the west. The sharp termination of the Iberian lithosphere occurs under the contact between the Alpujarride and the Nevado-Filabride complexes of the Alboran domain in an ENE-WSW right-lateral transpressive shear zone. The thickest crust and lithosphere do not correlate with the highest topography along the profile suggesting that this high topography is a combined effect of the positive flower structure, and the push up of the asthenosphere produced by the removal of the Iberian lithosphere.This work was sup-ported by the projects: CGL2015-67130-C2-2-R, GCL2012-31472 (TRANSCORBE), HIRE (GFZ Potsdam) and PP2012-PIJD003 (Granada University). We acknowledge work on free softwares SAC and GMT

Late orogenic doming in the Eastern Betics : final exhumation of the Nevado-Filabride complex and its relation to basin genesis.

The geometry, timing, and kinematics of late orogenic extension in the Betic Cordilleras pose the problem of a decoupling of upper crustal and lower crustal deformation regimes. Perpendicular directions of extension in metamorphic domes and nearby sedimentary basins remain unexplained. This paper puts kinematic constraints on the final exhumation of the Nevado-Filabride complex, focusing on the formation of metamorphic domes and their relations with the adjacent basins. Structural fabrics and kinematic indicators below the main shear zones as well as their relations with both published changing metamorphic P-T conditions and geochronological data were studied. Our approach describes (1) a consistent top-to-the-west shear parallel to dome axes of during D2 (i.e., during decompression) with distributed ductile flow and the onset of strain localization along major shear zones, (2) further strain localization along the major shear zones under greenschist facies conditions, during D3 leading to S-C′ mylonites formation accompanied with a rock strong thickness reduction, (3) the divergence of shear direction on either limbs of domes during D3 showing the appearance of the dome geometry, and (4) a local evolution toward N-S brittle extension (D4) in the upper plate and formation of sedimentary basins. Continuous ductile to brittle top-to-the-west shear is compatible with the slab retreat hypothesis from the Miocene; the formation of domes which adds gravitational forces responsible for the final stages of exhumation is thus characterized by important kinematics changes necessary to explain coeval N-S opened basins. Later, from the upper Tortonian, a contractional event (D5) amplified the earlier domal structures forming the present north vergent folds

Burgdorf. Ehemaliges Siechenhaus. Ergebnisse der archäologischen Grabungen und Bauforschung 1989–1991

Der Archäologische Dienst des Kantons Bern führte 1989–1991 beim ehemaligen Siechenhaus in Burgdorf Bauuntersuchungen und eine Ausgrabung durch, die neue Einblicke in das Alltagsleben der Siechen erlaubten. Da bisher nur Siechenkapellen und dazugehörige Friedhöfe bekannt waren, stellt das Siechenhaus von Burgdorf, das 1506/1508 erbaut wurde, schweizweit einen einmaligen Befund dar. Die Publikation umfasst die Vorlage der Befunde und Funde, wobei der Aussen- und Innenbau besonders detailliert vorgelegt und diskutiert wird

Bern. Die Skulpturenfunde der Münsterplattform. Katalog der figürlichen und architektonischen Plastik

Restaurierungsarbeiten auf der Münsterplattform in Bern führten 1986 zur Entdeckung einer Schüttungsschicht mit insgesamt etwa 500 teils beschädigten Skulpturen. Es handelt sich dabei um die Spuren des schriftlich überlieferten «Bildersturms», der – durch die Reformation 1528 ausgelöst – ein Zeugnis der Bildkritik der Reformatoren darstellt. Im Katalogband werden die Ausgrabungsresultate vorgelegt und die Restaurierung und Konservierung der Funde dokumentiert

Burgdorf Kornhaus. Eine mittelalterliche Häuserzeile in der Burgdorfer Unterstadt

In den Jahren 1988–1991 wurde das zuletzt als städtische Lagerhalle genutzte Kornhaus zum Schweizerischen Museum und Institut für Volksmusik und Musikinstrumente umgebaut. Der Eingriff machte archäologische Untersuchungen notwendig, die einen umfassenden Einblick in einen Teilbereich der mittelalterlichen Siedlung und deren Entwicklung gewährten, deren Ergebnisse in dieser Publikation vorgelegt werden. Der Fokus liegt dabei auf den mittelalterlichen Hausbauten und der Fundvorlage

Laufen Rathausplatz. Eine hölzerne Häuserzeile in einer mittelalterlichen Kleinstadt: Hausbau, Sachkultur und Alltag. Die Ergebnisse der Grabungskampagnen 1988 und 1989

Eine geplante Neupflästerung des Rathausplatzes von Laufen führte 1988/89 zu einer Rettungsgrabung, mit welcher sechs spätmittelalterliche (13.–16. Jh.) mehrphasige Häuser erfasst werden konnten. Die Publikation umfasst neben einer Einführung in den Naturraum und das historische Umfeld die detaillierte Auswertung der Hausbefunde und des umfangreichen Fundmaterials (inkl. botanische und osteologische Reste) und beleuchtet in der Synthese aus einer interdisziplinären Perspektive das Alltagsleben in der spätmittelalterlichen Stadt Laufen