Seismic tomography models of the three-dimensional upper mantle velocity structure of the Mediterranean-Carpathian region provide a better understanding of the lithospheric processes governing its geodynamical evolution. Slab detachment, in particular lateral migration of this process along the plate boundary, is a key element in the lithospheric dynamics of the region during the last 20 to 30 million years. It strongly affects arc and trench migration, and causes along-strike variations in vertical motions, stress fields, and magmatism. In a terminal-stage subduction zone, involving collision and suturing, slab detachment is the natural last stage in the gravitational settling of subducted lithosphere.

http://www.mantleplumes.org/WebDocuments/Wortel2000.pdf

Subduction and Slab Detachment in the Mediterranean-Carpathian Region

An Astronomically Tuned Neogene Time Scale (ATNTS2012) is presented, as an update of ATNTS2004 in GTS2004. The new scale is not fundamentally different from its predecessor and the numerical ages are identical or almost so. Astronomical tuning has in principle the potential of generating a stable Neogene time scale as a function of the accuracy of the La2004 astronomical solution used for both scales. Minor problems remain in the tuning of the Lower Miocene. In GTS2012 we will summarize what has been modified or added since the publication of ATNTS2004 for incorporation in its successor, ATNTS2012. Mammal biostratigraphy and its chronology are elaborated, and the regional Neogene stages of the Paratethys and New Zealand are briefy discussed. To keep changes to ATNTS2004 transparent we maintain its subdivision into headings as much as possible.

The Neogene Period

Geological atlas of western and central Europe

The new tectonic map of the Alps is based on the combination of purely structural data with criteria regarding paleogeographical affiliation and/or tectono-metamorphic evolution. The orogenic evolution of the Alps is discussed using a combination of maps and paleogeographical reconstructions. It is proposed that the Alps are the product of two orogenies, a Cretaceous followed by a Tertiary one. While the former is related to the closure of an embayment of the Meliata ocean into Apulia, the latter is due to the closure of the Alpine Tethys between Apulia and Europe. The along-strike changes in the overall architecture, as for example revealed by geophysical-geological transects, are by far more substantial than hitherto believed. It appears that the Alps are still far from being over-investigated, as is demonstrated by many surprising recent findings based on field geology, laboratory results and geophysical methods of deep sounding.

/pdf/tectonic-map-and-overall-architecture-of-the-alpine-orogen-23efh3jp0j.pdf

Tectonic map and overall architecture of the Alpine orogen

A correlation of tectonic units of the Alpine-Carpathian-Dinaridic system of orogens, including the substrate of the Pannonian and Transylvanian basins, is presented in the form of a map. Combined with a series of crustal-scale cross sections this correlation of tectonic units yields a clearer picture of the three-dimensional architecture of this system of orogens that owes its considerable complexity to multiple overprinting of earlier by younger deformations.

/pdf/the-alpine-carpathian-dinaridic-orogenic-system-correlation-2gm3qeefzn.pdf

The Alpine-Carpathian-Dinaridic orogenic system: correlation and evolution of tectonic units

Map 1. Late Eocene (Priabonian-Beloglinian) -- Map 2. Early Oligocene (Early Rupelian, Early Kiscellian - Pschekhian) -- Map 3. Late Oligocene (Chattian - Egerian - Kalmykian) -- Map 4. Early Miocene (Burdigalian, Eggenburgian, Sakaraulian) -- Map 5. Early Middle Miocene (Langhian, Early Badenian, Chokrakian) -- Map 6. Mid Middle Miocene (Middle Serrvallian, Late Badenian, Konkian) -- Map 7. Late Middle Miocene (Late Serrvallian, Sarmatian s.s., Middle Sarmatian s.l.) -- Map 8. Mid Late Miocene (Late Tortonian - Early Messinian - Early Maeotian - Late Pannonian) -- Map 9. Latest Miocene (Late Messinian, Early Pontian - Late Pannonian) -- Map. 10. Middle Late Pliocene (Piacentian - Gelasian, Late Romanian - Akchagilian) -- [chart] Stratigraphic scheme of the Late Paleogene - Neogene Paratethys and mapped intervals.

Lithological-paleogeographic maps of Paratethys : 10 maps late Eocene to Pliocene

Tertiary evolution of the Intra-Carpathian area: A model

Lithological -paleogeographic maps of paratethys

The Miocene Central Paratethys Sea covered wide areas of the Pannonian Basin System, bordered by the mountain chains of the Alps, Carpathians and Dinarides. The epicontinental sea spread not only in the back-arc basin area, but flooded even the Alpine-Carpathian Foredeep, situated along the front of gradually uplifting mountains. The Early Badenian (early Langhian) transgressions from the Mediterranean toward the Central Paratethys realm, via Slovenia and northern Croatia (Transtethyan Trench Corridor or Trans Dinaride Corridor) flooded the Pannonian Basin and continued along straits in the Carpathian Chain into the Carpathian Foredeep. The isolation of eastern parts of the Central Paratethys at the end of this period (late Langhian) resulted in the "Middle Badenian" salinity crisis. Thick evaporite sediments, above all halite and gypsum were deposited in the Transcarpathian Basin, Transylvanian Basin and Carpathian Foredeep. During the Late Badenian (early Serravallian), the latest full marine flooding covered the whole back-arc basin and a great part of the foredeep. The main problem is to create a model of sea connections during that time, because some authors consider the western Transtethyan Trench Corridor (Trans Dinaride Corridor) closed and there is no evidence to prove a supposed strait towards the Eastern Mediterranean. A proposed possibility is a connection towards the Konkian Sea of the Eastern Paratethys. The Badenian climate of the Central Paratethys realm can be characterized as fairly uniform, reflecting the stable subtropical conditions of the Miocene Climatic Optimum. No considerable changes in terrestrial ecosystems were documented. Nevertheless, evolution of steep landscape associated with rapid uplift of the East Alpine and Western Carpathian mountain chains (including high stratovolcanoes) caused development of vertical zonation of dry land and consequently close occurrence of different vegetation zones in a relatively small distance during this time. In the Central Paratethys Sea a slight N-S climatic gradient seems to be expressed already from the Early Badenian, but a biogeographic differentiation between basins in the North and South starts to become more prominent first during the Late Badenian, when a moderate cooling of the seawater can also be documented. The Late Badenian sea-level highstand coincides with the appearance of stress factors such as stratification of the water column and hypoxic conditions at the basin bottom in the whole area. Taking into account all bioevents and changes of paleogeography in the Central Paratethys realm, we can very roughly correlate the Early (and "Middle") Badenian with the eustatic sea-level changes of TB 2.3, TB 2.4 or Bur5/Lan1, Lan2/Ser1 and the Late Badenian with TB 2.5 or Ser2 cycles (sensu Haq et al. 1988; Hardenbol et al. 1998). Generally, we can assign the Early Badenian transgressions to be controlled by both, tectonics (induced mainly by back-arc basin REVIEW

Badenian evolution of the Central Paratethys Sea: paleogeography, climate and eustatic sea level changes

Geodynamic evolution of the Carpathian arc and Pannonian basin during the Neogene times is presented as a set of palinspastic reconstructions. The structural evolution is modeled in terms of a coupled system of: (1) Alpine (Atype) subduction and compressive orogene belt development owing to compression by the Adriatic microplate, (2) lateral extrusion of Alcapa lithosphere from the Alpine collision assisted by transform faults, (3) Carpathian gravity driven (Btype) subduction of oceanic or suboceanic lithosphere underlying former flysch basins and (4) back arc extension associated with the diapiric uprise of asthenospheric mantle. The variable timing of accretionary prism and back arc basin evolution in the Western Carpathians, the NW part of the Eastern Carpathians, and the SE part of the Eastern Carpathians confirms that the final Tertiary evolution of the Carpathian arc and Pannonian basin was not a uniform process. Rather, it took place successively in three segments, reflecting gravity driven subductions compensated by return asthenospheric flows (involving the back-arc diapiric uprise of asthenospheric mantle). The observed low subduction rate implies obstacles to the compensating asthenosphere flow, perhaps represented by confining thick lithosphere at the NW and SE sides of the arc. This segmentation may arise from a gravity driven process allowing asthenospheric side flow to take place speeding up the gravity driven overturn (subduction). Structural evolution as well as the timing and spatial distribution of the arc-type (subduction-related) andesite volcanics suggests that subduction halted because the subducting plate became nearly vertical, followed closely by the detachment of the sinking lithosphere slab from the continental margin. Late stage alkali basalt volcanic rocks imply that during the final stage of back arc basin evolution the related diapiric uprise of asthenospheric mantle incorporated unmetasomatized mantle material, brought possibly into the area of the diapiric uprise by compensating athenosheric mantle counterflows. Correspondence to: J. Lexa (lexa@gssr.sk)

/pdf/neogene-evolution-of-the-carpatho-pannonian-region-an-1iwu5izhd1.pdf

Michal Kováč

Papers

Lithological-paleogeographic maps of Paratethys : 10 maps late Eocene to Pliocene

Tertiary evolution of the Intra-Carpathian area: A model

Lithological -paleogeographic maps of paratethys

Badenian evolution of the Central Paratethys Sea: paleogeography, climate and eustatic sea level changes

Neogene evolution of the Carpatho-Pannonian region: an interplay of subduction and back-arc diapiric uprise in the mantle