Middle Miocene

... the Periadriatic–Drava fault in the marginal zone of Pohorje Mts., 7 km along the southern marginal fault of the Pannonian basin in the vicinity of Karlovac, and 10 km along the branching fault of the Periadriatic–Drava fault marking the southern border of the Kalnik–Ivan ica Mts. ...

1] The long-term erosional evolution of relief is revealed by low-temperature thermochronometric data, whereas geomorphic features give constraints on the short-term evolution. We discuss the topographic evolution of northeastern Corsica by fission track and (U-Th)/He dating of apatite, the provenance of Neogene alluvial sediments, an analysis of uplifted strath terraces, and the shape of river profiles. Cooling ages indicate high cooling rates of up to 40°C/Myr during the early-middle Miocene, when this region was affected by extensional tectonics. Cooling rates are less than 7.5°C/Myr from the middle Miocene to the present, when topographic perturbations are detected by variations in the source areas of middle-to-late Miocene alluvial sediments and by the presence of large-scale irregularities along modern river longitudinal profiles. We suggest that the contrast of slow long-term erosion rates and the high local relief in the present Corsican landscape require that the landscape be in a transient state in response to a recent tectonic event. Citation: Fellin, M. G., M. Zattin, V. Picotti, P. W. Reiners, and S. Nicolescu (2005), Relief evolution in northern Corsica (western Mediterranean): Constraints on uplift and erosion on long-term and short-term timescales,

The NNE-SSW striking Giudicarie Fault System (composed of the Northern and Southern Giudicarie Fault and the Meran-Mauls Fault) represents a distinctive bend and offset in the Periadriatic Fault System (PFS). It terminates the E-W striking Tonale Fault Zone to the east, and the ESE-WNW striking Pustertal-Gailtal Fault to the west. Along the Giudicarie Fault System Oligocene tonalitic bodies occur, subsumed under the term 'Oligocene Tonalitic lamellae'. Along the southern part of the Northern Giudicarie Fault only a few < 50 m thick and 200 m long lenses crop out, often strongly affected by brittle deformation. So far no tonalitic bodies have been found between the locality Rumo (Val di Non) and Pawigl (south of Meran), i.e. for some 20 km. From Pawigl to the NE the lenses are more continuous, up to 150 m thick and less affected by brittle deformation. Fission Track analyses was carried out on samples from tonalitic lenses along the Northern Giudicarie Fault and the Meran ...

The Romeral Fault System (RFS) extends 1600 km from Barranquilla-Colombia to Talara city-Peru and before the Pliocene. In the Middle Eocene RFS defi ned the northwestern border of the South America plate, being originated by a triple junction rift- rift- rift occurred from lower to middle Jurassic, when the South American sector separated from Chortis, Oaxaca and Yucatan blocks. From Late Mesozoic until Early Paleocene, the Paleo Pacifi c plate converged on NW South America corner being subducted when an anomalous thick oceanic crust, represented by the Caribbean plate, was accreted extinguishing gradually from the North of Peru to the North of Colombia. The collision generated a transtensive fi eld stress in back arc region, due to the ancestral Central Cordillera rising in continental border. The RFS rocks suffered low grade metamorphism and some rocks of extinct subduction zone suffered metamorphic inversion. During Late Paleogene until Early Miocene, the convergence South Americ...

The distribution of seismic units in deposits of the basins near the Antarctic-Scotia plate boundary is described based on the analysis of multichannel seismic reflection profiles. Five main seismic units are identified. The units are bounded by high-amplitude continuous reflectors, named a to d from top to bottom. The two older units are of different age and seismic facies in each basin and were generally deposited during active rifting and seafloor spreading.

A thick sequence of volcaniclastic sediments drilled at site 953 during Ocean Drilling Program (ODP) Leg 157 northeast of Gran Canaria (Canary Islands) contains an almost complete magneto-stratigraphy back to the shield stage of the island 14.8 Ma ago. Onshore, a sequence of reversals has been identified and dated in 19 dominantly peralkaline rhyolitic ignimbrites, one rhyolitic, and one basaltic lava flow of the Mogán Group (13.35–13.95 Ma), which overlie basalt flows of the island's shield stage (>14 Ma). The magneto-stratigraphy of the ignimbrites onshore has been correlated with the marine magneto-stratigraphy at site 953, determined in syn-ignimbritic volcaniclastic turbidites, which were deposited practically synchronously immediately following the entry of the parent pyroclastic flows into the sea around the circumference of the island. The four polarity intervals recorded in the sequence of the Mogán Group ignimbrites correspond to C5ACr, C5ACn, C5ADr and C5ADn. Single crystal 40Ar/39Ar-age determinations of the ignimbrites bracketing the polarity changes gave the following ages and uncertainties for the reversals C5AD (t) (13.95±0.07 Ma), C5AC(o) (13.89±0.08 Ma), and C5AC(t) (13.47±0.09 Ma). The newly dated polarity changes fit and refine the Miocene age model proposed in the global polarity time scale.

The present-day bathymetric profile in the Ross Sea, as in other regions around the Antarctic margin, is deepening landward and shows unusually high water-depths: up to 1000 m in the inner shelf. These two features are the product of multiple ice sheet advances and retreats on the continental shelf. In this paper, we present a reconstruction of paleo-bathymetric profiles of the Eastern Ross Sea throughout the Cenozoic. The evolution of the sea-floor morphology from shallow and seaward dipping to the present-day configuration gives new insights into the understanding of the West Antarctic Ice Ž . Sheet WAIS history in this sector. Paleo-bathymetric profiles have been calculated by applying a reverse post-rift modelling, starting from a cross-section derived from multichannel seismic data. The post-rift reverse modelling includes: sediment decompaction, isostatic compensation after removing and recovering sediments of the post-rift thermal subsidence. The major uncertainty in our model is due to the paucity of stratigraphic constraints for the late Miocene and Pliocene sequences that prevents precise values of paleowater-depth being estimated. Nevertheless, major changes in the shape of the continental shelf and slope throughout the Cenozoic can be recognised, and mark some critical steps in the Ross Sea Ž . Ž evolution. 1 Pre-Miocene: the Eastern Ross Sea was a deep structural basin bordered to the west by areas e.g., the Central . High outcropping the sea level and hosting valley glaciers or small ice caps. A continental shelf edge was not clearly Ž . developed yet, the eastern flank of the Central High appeared as an inclined ramp, dipping towards the ocean. 2 Early to middle Miocene: tectonic subsidence gradually produced a marine flooding over most of the pre-Miocene sub-aerial areas. A continental shelf, slope and rise are gradually delineated. The shelf profile was seaward dipping and not yet overdeepened.

An incomplete dolphin skeleton was found and excavated in the Brusturilor Valley near the village Tngad (Bihor County, Romania) in 2000. The remains came from a layer of greenish clay that was deposited in the Early Sarmatian. The carcass was likely complete when it reached the sea floor, but the skeleton was slowly buried in a disturbed environment where the elements became unassociated and displaced. The dolphin from Tigad is a delphinoid, whose periotic closely resembles those of Miocene kentriodontids. A comparison of these elements to known kentriodontid species suggests that the dolphin ofTdgad represents a new species. In the lack of the diagnostic features of the skull, however, its formal description must await the discovery of more complete material.

The brickyard of Baden-Sooss, in the Austrian part of the Vienna Basin was selected as the stratotype of the Middle Miocene regional stage Badenian for the Central Paratethys. Stratigraphy and correlation are up-dated, and the present state of the art on fossil groups is shown. The stratotype belongs to the Upper Lagenidae Zone in a regional paleoecological zonation. For interregional correlation the section belongs to a part of calcareous nannoplankton Zone NN5 without Helicosphaera waltrans, to dinocyst Zone Cte, and in planktonic foraminiferal zonation by the occurrence of Orbulina suturalis to Zone M6, and to the middle part of the Langhian stage. The sediments of the so-called "Badener Tegel" are part of the Baden Formation, correlated with the Lanžhot Formation in the Czech and Slovak part of the basin. Deposition of the calcareous silty clays occurred at a water depth of around 200 m in a relatively warm, well-stratified water column. Re-deposition of fossiliferous coarser sediments from shallow regions occurs.

There are three parallel magmatic arcs in the northwest of Iran, of Cretaceous and Eocene-Miocene to Quaternary ages, trending in a NW-SE direction between the Main Zagros Thrust (MZT) in the southwest and the Tabriz Fault in the northeast. In this study, these volcanic belts are referred to as the Sanandaj Cretaceous volcanic (SCV), Sonqor-Baneh volcanic (SBV), and Hamedan-Tabriz volcanic (HTV) belts, respectively. The SCV belt consists mainly of mafic to intermediate submarine rocks with calc-alkaline affinity, and the SBV belt is composed of basalt, gabbro to dioritic bodies, with extrusive to subvolcanic magmatic textures and tholeiitic to alkaline affinity. These extend along the MZT between the Zagros ophiolite in the west and the SCV belt in the east. The HTV belt is part of the Urmieh-Dokhtar Magmatic Arc belt that extends across the Hamedan to Tabriz, and was active in the Miocene to Quaternary. The petrology and geochemistry of the northwestern Iranian volcanic zones indicate that they were generated at an active continental margin. In addition to the volcanic belts, there is a dismembered ophiolite along the MZT from Kermanshah to Turkey, in a NW-SE direction. These ophiolites are remnants of Neo-Tethyan oceanic crust which was obducted over the Arabian passive margin in the late Cretaceous. In this study, we propose that a collision between the Arabian and Iranian plates may have occurred in the middle to late Miocene, and that the Neo-Tethyan oceanic subduction beneath northwestern Iran ceased for a while. As a result, a gap in volcanic activity occurred between the Cretaceous and the Middle Miocene-Quaternary volcanism events. This gap in activity is not observed in southwestern Iran.

Cockatoos are the distinctive family Cacatuidae, a major lineage of the order of parrots (Psittaciformes) and distributed throughout the Australasian region of the world. However, the evolutionary history of cockatoos is not well understood. We investigated the phylogeny of cockatoos based on three mitochon- drial and three nuclear DNA genes obtained from 16 of 21 species of Cacatuidae. In addition, five novel mitochondrial genomes were used to estimate time of divergence and our estimates indicate Cacatuidae diverged from Psittacidae approximately 40.7 million years ago (95% CI 51.6–30.3 Ma) during the Eocene. Our data shows Cacatuidae began to diversify approximately 27.9 Ma (95% CI 38.1–18.3 Ma) during the Oligocene. The early to middle Miocene (20–10 Ma) was a significant period in the evolution of modern Australian environments and vegetation, in which a transformation from mainly mesic to xeric habitats (e.g., fire-adapted sclerophyll vegetation and grasslands) occurred. We hypothesize that this environmen- tal transformation was a driving force behind the diversification of cockatoos. A detailed multi-locus molecular phylogeny enabled us to resolve the phylogenetic placements of the Palm Cockatoo (Probosciger aterrimus), Galah (Eolophus roseicapillus), Gang-gang Cockatoo (Callocephalon fimbriatum) and Cockatiel (Nymphicus hollandicus), which have historically been difficult to place within Cacatuidae. When the molecular evidence is analysed in concert with morphology, it is clear that many of the cockatoo species’ diagnostic phenotypic traits such as plumage colour, body size, wing shape and bill morphology have evolved in parallel or convergently across lineages.

The Iberian Peninsula has a complete Mio-Pliocene fossil record in which all biostratigraphic units are represented. As a consequence, there is an exceptional proboscidean record including deinotheres, mastodonts and elephants, which has increased significantly in recent years. Many of the older localities are not known in the common paleontological literature because only or mainly proboscidean remains were collected. This paper presents an overview of the localities yielding mastodont remains.

Stable isotope data of the foraminiferal carbonate shells and bulk sediment samples from the Central Paratethys were investigated to contribute to better knowledge of the paleoenvironmental changes in Badenian (Middle Miocene). Five benthic (Uvigerina semiornata, U. aculeata, Ammonia beccarii, Elphidium sp. and Heterolepa dutemplei) and three planktonic taxa (Globigerina bulloides, G. diplostoma and Globigerinoides trilobus), characterising the bottom, intermediate and superficial layers of the water column, were selected from the Vienna Basin (W Slovakia). The foraminiferal fauna and its isotope signal point out to temperature-stratified, nutrient-rich and consequently less-oxygenated marine water during the Middle/Late Badenian. Negative carbon isotope ratios indicate increased input of 12 C-enriched organic matter to the bottom of the Vienna Basin. Positive benthic d 18 O implies that the global cooling tendency recorded in the Middle Miocene has also affected the intramountain Vienna Basin. In this time, the Central Paratethys has been in the process of isolation. Our stable isotope trend suggests that the communication with Mediterranean Sea has been still more or less active on the south of Vienna Basin (Slovak part) in the Late Badenian, whereas the seawater exchange towards north was apparently reduced already during the Middle Badenian.

Vermetids are a poorly known family of reef-building gastropods characterized by an extremely irregular growth of the shell. Vermetid reefs are known from the Badenian (Middle Miocene) to present-day and their main importance is related to their use as sea-level indicators, strictly associated to the intertidal or immediate subtidal zone. During their evolution, two different vermetid genera have been recognized as reef-builders: Petaloconchus was the major component of vermetid reefs until the Holocene when, for still unknown reasons, it was almost completely replaced by Dendropoma. In the Mediterranean Basin, Petaloconchus reefs have been frequently found in close association to Late Miocene coral bioconstructions. New finding of Petaloconchus reefs within the slope facies of the Salento Messinian reef complex (southern Italy), together with new data from late Tortonian-early Messinian reefs of Crete (Greece) provide further information on the palaeoecology of these peculiar bioconstructions. Stratigraphical and sedimentological contexts of Salento and Crete vermetid reefs have been described, together with an account of their size, shape and inner structure. Biotic (vermetids, serpulids, bryozoans and coralline algae) and abiotic components (early marine cements and intra-reef sediment) have been identified by microfacies analysis, and their percentage-abundance has been reported. These data allow the description of vermetid reefs from two different depositional settings: along the shelf edge and, for the first time, within the coral reef slope. Shelf-edge and slope Petaloconchus reefs show the same inner structure and composition, but they differ by their shape, by the density of the framework, and by the relative proportion of the associated reef-building organisms (serpulids, bryozoans and coralline algae). Additional information on their palaeobathymetric setting have been acquired from the presence of other reef-building biota (Porites corals and Halimeda green algae) which occur in close proximity to slope vermetid reefs, together with observations on some anatomical feature of Petaloconchus shells. Results clearly indicate for Petaloconchus reefs a palaeobathymetric range spanning from the upper subtidal zone down to 30-50 m of depth. The present study confirms vermetid reefs as important tools for the reconstructions of ancient sea-level, but great attention has to be paid to the identification of the main reef-building vermetid. Actually, while a great number of present-day Dendropoma reefs can be associated to the mean sea-level, Late Miocene vermetid reefs from Salento and Crete indicate for Petaloconchus bioconstructions a wider palaeobathymetric range.

Ocean Drilling Program Leg 133 core data, samples, and geophysical data (logs and seismics) were analyzed to document late Miocene--early Pliocene partial drowning of the Queensland Plateau carbonate platform off Northeast Australia. The modern plateau consists of a mosaic of pinnacle reefs and larger (10 × 50 km) reefs representing relicts of early to middle Miocene buildups. Late Miocene-early Pliocene floatstones, packstones, and mudstones, rich in the larger benthic foraminifers Lepidocyclina and Cycloclypeus, drilled in a transect of sites across the drowned margin of a middle Miocene buildup show that the late Pliocene partial drowning of the platform was preceded by 4 Myr of neritic carbonate deposition without any reefs. The carbonate factory was unable to aggrade to sea level during this period as indicated by the lack of any shallowing trend in the succession. Monitoring of the Miocene to Recent neritic shedding pattern on the windward and leeward side of a pinnacle reef on the Queensland Plateau supports this interpretation. Shedding on the leeward side of the reef, which records periods of active reef growth, played a minor role during the late Miocene, increased during the Pliocene, and reached very high values during the late Pliocene and Pleistocene. Shedding on the windward side of the reef, which was active during lowstands of relative sea level, occurred during the late middle-early late Miocene and during the Pliocene--Quaternary. The data presented here, when combined with paleoceanographic data points to low surface water temperatures (17°-19°C) as a major factor which suppressed reef growth during the late Miocene-early Pliocene period.

The Laventan Quebrada Honda Fauna of southern Bolivia is one of the best sampled middle Miocene South American faunas. The present study describes the toxodontid, interatheriid and mesotheriid notoungulates from Quebrada Honda and summarizes the present state of knowledge of the fauna. Toxodontid specimens from Quebrada Honda include two isolated molars, one upper and one lower. The upper molar compares favourably with Paratrigodon and may represent a new species, but too little material is known to make an adequate diagnosis. The lower molar may pertain to the same taxon, or to a distinct species that is even more poorly represented. A new species of the interatheriid Miocochilius is described, M. federicoi, on the basis of a partial skull. It differs from M. anomopodus in its significantly smaller size (at least 20 per cent smaller based on linear upper molar dimensions); relatively wider P4 with deeper lingual sulcus; more prominent middle lobes on upper molars; and M3 with deeper lingual sulcus and more prominent metastyle (distal lobe). The generic allocation of this new species is considered tentative, pending a better understanding of the phylogenetic relationships among currently recognized species of Miocochilius and Protypotherium. Mesotheriids are represented at Quebrada Honda by a pair of poorly preserved mandibles that are referred to Plesiotypotherium minor, a species previously recorded from slightly older deposits near Cerdas, Bolivia. A newly revised faunal list for Quebrada Honda is compiled that includes 30 species of non-volant mammals, 27 of which have been identified to at least genus level. This revised faunal list is used to compare Quebrada Honda to other well-sampled middle-late Miocene faunas (including La Venta, Columbia; Colló n-Curá, Argentina; and Arroyo Chasicó , Argentina) using the Simpson Index of faunal similarity. In order to compensate for inadequately identified specimens (i.e. those not identified to genus level), minimum and maximum values of faunal similarly were estimated using two different sets of assumptions. The analysis indicates that the middle-latitude Quebrada Honda Fauna is more similar to the slightly older high-latitude fauna of Colló n-Curá than to the contemporaneous low-latitude fauna of La Venta, suggesting that isolating mechanisms between the low and middle latitudes were in place during the early and ⁄ or middle Miocene. The relative paucity of taxa shared between Quebrada Honda and La Venta, despite their contemporaneity, suggests that the system of South American Land Mammal 'Ages' (SALMAs) may not be useful for biocorrelation between low-latitude faunas and those from elsewhere in South America.

The world's river dolphins [Inia, Pontoporia, Lipotes and Platanista) are among the least known and most endangered of all cetaceans. The four extant genera inhabit geographically disjunct river systems and exhibit highly modified morphologies, leading many cetologists to regard river dolphins as an unnatural group. Numerous arrangements have been proposed for their phylogenetic relationships to one another and to other odontocete cetaceans. These alternative views strongly affect the biogeographical and evolutionary implications raised by the important, although limited, fossil record of river dolphins. We present a hypothesis of river dolphin relationships based on phylogenetic analysis of three mitochondrial genes for 29 cetacean species, concluding that the four genera represent three separate, ancient branches in odontocete evolution. Our molecular phylogeny corresponds well with the first fossil appearances of the primary lineages of modern odontocetes. Integrating relevant events in Tertiary palaeoceanography, we develop a scenario for river dolphin evolution during the globally high sea levels of the Middle Miocene. We suggest that ancestors of the four extant river dolphin lineages colonized the shallow epicontinental seas that inundated the Amazon, Parana, Yangtze and Indo-Gangetic river basins, subsequently remaining in these extensive waterways during their transition to freshwater with the Late Neogene trend of sea-level lowering.

The rhynchonellid brachiopod species Cryptopora lovisati has been identified in the Middle Miocene sandy deposits of France, and its ontogeny and variability are described. This is the first record of the genus Cryptopora Jeffreys from France, although several species of Cryptopora have been already reported from other regions of Europe. Being known since the Lower Palaeocene, Cryptopora is widely distributed in modern seas, ranging from about 60 m down to over 4000 m, and is represented by six extant and about 12 fossil species. C. lovisati has been interpreted as relatively shallow water species living attached to the sediment by a long pedicle. The affinity between C. lovisati and Recent C. curiosa Cooper is discussed.

Cenozoic eastward migration of the Caribbean plate relative to the South American plate is recorded by an 1100-km-long Venezuela-Trinidad foreland basin which is oldest in western Venezuela (65-55 Ma), of intermediate age in eastern Venezuela (34-20 Ma) and youngest beneath the shelf and slope area of eastern offshore Trinidad (submarine Columbus basin, 15.0 Ma-Recent). In this study of the regional structure, fault families, and chronology of faulting and tectonic events affecting the hydrocarbon-rich Columbus foreland basin of eastern offshore Trinidad, we have integrated approximately 775 km of deep-penetration 2D seismic lines acquired by the 2004 Broadband Ocean-Land Investigations of Venezuela and the Antilles arc Region (BOLIVAR) survey, 325 km of vintage GULFREX seismic data collected by Gulf Oil Company in 1974, and published industry well data that can be tied to some of the seismic reflection lines. Top Cretaceous depth structure maps in the Columbus basin made from integration of all available seismic and well data define for the first time the elongate subsurface geometry of the 11-15 km thick and highly asymmetrical middle Miocene-Recent depocenter of the Columbus basin. The main depocenter located 150-200 km east of Trinidad and now the object of deepwater hydrocarbon exploration is completely filled by shelf and deepwater sediments derived mainly from the Orinoco delta. The submarine Darien ridge exhibits moderate (20-140 m) seafloor relief, forms the steep (12-24), northern structural boundary of the Columbus basin, and is known from industry wells to be composed of 0.5-4.5 km thick, folded and thrust-imbricated, hydrocarbon-bearing section of Cretaceous and early Tertiary limestones and clastic rocks. The eastern and southern boundaries of the basin are formed by the gently (1.7-4.5), northward-dipping Cretaceous-Paleogene passive margin of South America that is in turn underlain by Precambrian rocks of the Guyana shield. Interpretation of seismic sections tied to wells reveals the following fault chronology: (1) middle Miocene thrusting along the Darien ridge related to highly oblique convergence between the Caribbean plate and the passive margin of northern South America; continuing thrusting and transpression in an oblique foreland basin setting through the early Pleistocene; (2) early Pliocene-recent low-angle normal faults along the top of the Cretaceous passive margin; these faults were triggered by oversteepening related to formation of the downdip, structurally and bathymetrically deeper, and more seaward Columbus basin; large transfer faults with dominantly strike-slip displacements connect gravity-driven normal faults that cluster near the modern shelf-slope break and trend in the downslope direction; to the south no normal faults are present because the top Cretaceous horizon has not been oversteepened as it is adjacent to the foreland basin; (3) early Pliocene-Recent strike-slip faults parallel the trend of the Darien ridge and accommodate present-day plate motions.

Die Lage der Gemeinde Winden zwischen
den Abhängen des Leithagebirges und
dem Westufer des Neusiedler Sees weist
nicht nur in historischer, sondern auch aus geowissenschaftlicher
Sicht überaus interessante Aspekte
auf. Die Positionierung an einer uralten Nord-Süd
Hauptverkehrsader, der Bernsteinstraße1, sowie
die Verfügbarkeit von diversen Rohstoffen und ein
fruchtbarer Boden stellten günstige Bedingungen
für eine prosperierende Gemeinde dar. Neben dem
Weinbau war in der Vergangenheit aber vor allem
die Gewinnung von Baugesteinen von großer
wirtschaftlicher Bedeutung. Vor allem die nahezu
weißen, fein- bis grobkörnigen miozänen Leithakalke
wurden in mehreren, bis in römische Zeiten
zurückgehenden Steinbrüchen in großer Menge
abgebaut. Die morphologischen und bodenkundlichen
Eigenheiten der Gemeinde stehen naturgemäß
in engem Zusammenhang mit dem geologischen
Aufbau dieser Region. Die Beschreibung
der geologischen Verhältnisse des Windener Untergrundes
erfordert ein etwas weiteres Ausholen,
da die vorliegende Situation eng mit der jüngsten
geologischen Geschichte des Ostalpen–Karpaten–
Gebirgssystems im Neogen zusammenhängt. Besonders
hervorzuheben sind hier die Entstehung des
Wiener Beckens, des Eisenstädter Beckens und der
Kleinen Ungarischen Tiefebene.

The study provides a regional seismic interpretation and mapping of the Mesozoic and Cenozoic succession of the Lusitanian Basin and the shelf and slope area off Portugal. The seismic study is compared with previous studies of the Lusitanian Basin. From the Late Triassic to the Cretaceous the study area experienced four rift phases and intermittent periods of tectonic quiescence. The

1] The Rhodope Metamorphic Province in the area around the Mesta Graben (SW Bulgaria) exposes a structurally lower complex, the Pangaion-Pirin Complex of Variscan continental crust and its cover (mostly orthogneiss and marble), and a higher complex, the Rhodope Terrane of mixed oceanic and continental origin with metamorphosed Jurassic arc magmatites. The boundary between the two is the top-to-thesouthwest Nestos Shear Zone. The regional top-tothe-southwest shearing of the two basement complexes is related to the emplacement of the Rhodope Terrane over the Pangaion-Pirin Complex along this shear zone. Syntectonic and posttectonic Alpine intrusions within the basement can provide age limits for the thrusting. Zircons from the posttectonic Teshovo (south Pirin) Granitoid Pluton in the Pangaion-Pirin Complex yielded crystallization ages of 32 ± 0.2 Ma (LA-SF-ICP-MS U-Pb method). Zircons from two syntectonic granite plutons in the Rhodope Terrane (Dolno Dryanovo and Spanchevo) have circa 143 to 145 Ma old inherited magmatic cores and circa 55 to 56 Ma old magmatic rims. These ages, especially the presence of the Upper Jurassic/Lower Cretaceous cores in the plutons from the Rhodope Terrane, and the structural relations indicate that the southwestward thrusting of the Rhodope Terrane over the Pangaion-Pirin Complex took place in the Paleogene. A model is proposed in which the Pangaion-Pirin Complex represents the margin of Apulia and the structure of the Rhodopes is explained by a switch of subduction polarity from SW dipping in the Jurassic and Early Cretaceous to NE dipping in the Late Cretaceous and Paleogene. Citation: Jahn-Awe, S., N. Froitzheim, T. J. Nagel, D. Frei, N. Georgiev, and J. Pleuger (2010), Structural and geochronological evidence for Paleogene thrusting in the western Rhodopes, SW Bulgaria: Elements for a new tectonic model of the Rhodope

Sedimentologicand biostratigraphic studies from the Oligocene to Middle Miocene deposits, exposed in central and north Tunisia, lead to a sequence stratigraphy subdivision of these deposits into several third order depositional sequences. The north-south correlations show that the detrital quartz pebbles appeared much later in central Tunisia (within a 'fluvial-deltaic' complex), than in the Numidian in northern Tunisia (characterised by deep submarine channels filled with high density turbidites). Thus, in central Tunisia, the Fortuna Formation (from Rupelian to Lower Burdigalian) could not have supplied Numidian sands from the Saharan region as has been proposed by several authors. © 2000 Académie des sciences / Éditions scientifiques et médicales Elsevier SAS

Eobalaenoptera harrisoni, gen. et sp. nov., is described from a partial skeleton collected from the middle Miocene Calvert Formation of Virginia. Characteristics of this taxon, particularly of the petrosal, indicate that the new whale is a member of the clade that includes the Balaenopteridae (rorquals) and Eschrichtidae (gray whales) to the exclusion of “cetotheres” and the Balaenidae (right whales). Some of the probable synapomorphies of this clade include an elongate pars cochlearis, a tubular internal auditory meatus, the greater petrosal nerve foramen on the tympanic side of the petrosal, the stylomastoid fossa extending onto the posterior process of the petrosal, no medial groove on the pars cochlearis, four digits on each forelimb, depressed supraorbital processes, and ascending processes of maxillae extending onto the vertex. The approximate 14-million-year age of the specimen makes it the oldest known member of the clade by some 3 to 5 million years, and extends the fossil record of this clade closer to the divergence time estimated by some recent molecular studies.

We describe an early middle Miocene (late Langhian) terrestrial mollusc fauna from Nowa Wieś Królewska at Opole in Silesia (Poland). This survey is based on the rich collection stored in the Natural History Museum in Vienna and represents the first revision of this classical fauna. The assemblage is extraordinarily diverse and comprises 82 gastropod species and one bivalve species. About 56% of the taxa are known so far only from Nowa Wieś Królewska, emphasizing the preeminent position of this fauna within the European Neogene. The fauna reveals taxonomic affinities with early and early middle Miocene faunas. Stratigraphic overlap of several species and genera would suggest a correlation with the mammal biozone MN 5; integrating mammal data, however, indicates correlation with the biozone MN 6. This discrepancy is explained best by the lack of other adequately revised European MN 6 mollusc faunas. Consequently, the fauna from Nowa Wieś Królewska is proposed here as type of a MN 6 mollusc fauna in Central Europe. As such, this fauna represents the best-documented terrestrial mollusc fauna from the late Miocene Climate Optimum. Semi-quantitative abundance data of the terrestrial gastropods suggests the presence of ephemeral ponds and fens that formed on Cret-aceous limestones, surrounded by forested environments with leaf litter and dead wood. Occidentina gen. nov., Mennoia gen. nov., Neubertella gen. nov. and Eurocystina gen. nov. are described as new genera. Martinietta kadolskyi sp. nov., Carychium stworzewiczae sp. nov., Gastrocopta (Albinula) polonica sp. nov., Leiostyla piserai sp. nov., Vertigo antipygmaea sp. nov., Mennoia sculpturata sp. nov., Neubertella pulchra sp. nov., Aegopinella depressula sp. nov., Eurocystina nordsiecki sp. nov. and Vitrea angustaeumbilicata sp. nov. are introduced as new species. •

Middle Miocene chalicotheriine remains from France have played an important part in the palaeontological history of chalicotheres. For example, both the first known skull and first complete individual come from Sansan (MN 6, Gers, France). Nevertheless, these remains have never been described in detail until now. Firstly, cranial remains of Anisodon grande from Sansan are described. A review of nomenclatural problems supports Anisodon Lartet, 1851 as the appropriate genus name for this species and a new lectotype is designated. Secondly, the description of new remains of Chalicotherium goldfussi from Saint-Gaudens (MN 8, Haute-Garonne, France) considerably increases knowledge of this taxon. Thirdly, a skull from La Grive Saint-Alban (MN 7-8, Isère, France) is reassessed. A new cladistic analysis of the Chalicotheriinae is proposed incorporating these new data. This analysis, including 12 taxa and 51 cranio-mandibular and dental characters, supports the division of Middle and Late Miocene chalicotheriines into two clades. A novel pattern of relationships is proposed and the systematics is revised. However, chalicotheriine relationships remain labile because of the need for both a revision of pre-Middle Miocene taxa and the addition of postcranial data.

The fauna of gastropods and bivalves from the amber-bearing lithostratigraphic units of the Simojovel area, Chiapas is reported, including the description of two new species and one subspecies: Turbinella maya new species, Melongena corona tzeltal new subspecies and Agladrillia (Eumetadrillia) vermeiji new species. Stratigraphic affinities of the previously described species suggest an Early Miocene age for the Mazantic Shale, and a Middle Miocene age for the overlying Balumtum Sandstone. One specimen of gastropod, with a relatively large piece of amber attached to the adapertural part of the shell is representative for an Early Miocene age and estuarine paleoenvironmental interpretation for the Mazantic Shale. Mollusca, Miocene, Chiapas, Amber, Mexico.

In this paper, we describe a non-marine mollusk fauna deriving from late middle Miocene (late Serravallian; Sarmatian) deposits of western Serbia. The assemblage encompasses a diverse land snail fauna with twenty-four species, along with four species of freshwater pulmonate gastropods and one bivalve species. While the aquatic snails are ubiquitous elements in Europe during the middle Miocene, the terrestrial gastropod fauna, consisting of both common and rare species, offers the first comprehensive insight into land snail diversity on the Balkan Peninsula during that time and permits conclusions on regional biogeography. The fauna shows high affinities to the middle Miocene faunas of central Europe and shares only few elements with western and eastern European and Anatolian assemblages. Ecologically, the freshwater mollusks point to a standing or slowing moving, probably highly vegetated, lacustrine environment. The land snails indicate the presence of humid forests around Lake Vračević, which is in line with current climatic reconstruction for the Sarmatian of southeastern Europe. ?Vertigo vracevicensis Neubauer & Harzhauser sp. nov. and Pisidium mionicense Neubauer, Harzhauser & Mandic sp. nov. are introduced as new species. Discus costatus (Gottschick, 1911) is shown to be a junior objective synonym of Discus solarioides (Sandberger, 1872). •

The Ocean Drilling Program (ODP) Leg 161 drilled in the Western Mediterranean Sea (May-June, 1995) to investigate outstanding processes in the origin and structural evolution of the Alboran Basin. Studies at the Site 976 basement high, in the West Alboran Basin, demonstrate that the basin is floored with metamorphic rocks of continental origin (high-grade schist, migmatitic gneiss, marble, and calc-silicate rock, cross-cut by granite dikes) from the Alpujárride Complex of the Alboran Crustal Domain. Sediments encountered at the tops of the basement high are middle Miocene in age (about 11-12 Ma, late Serravallian). The pressure-temperature (P-T) evolution of the high-grade schist shows heating during decompression, from pressures of up to 10.5 kbar at about 500°C (corresponding to a burial depth of around 40 km) to final temperature conditions of 650º-700°C at a pressure of 3-4 kbar. The decompression was followed by cooling to T < 500º-600°C and P < 2-3 kbar. Ar/Ar dating on coexisting muscovite and biotite shows that this cooling occurred from 426°C at 20.0 ± 0.2 Ma to 330°C at 19.2 ± 0.7 Ma. Apatite fission-track shows that final cooling of the basement below 60°C took place at 18.3 ± 1.0 Ma (Burdigalian). Site 976 reveals two periods of subsidence, in the middle Miocene (synrift subsidence, at 11-10.7 Ma; rate of 3 km/m.y.) and since the latest Pliocene (postrift transtensive? subsidence, at 2.5-0 Ma earliest rate of 0.5 km /m.y.), and uplift at 5-2.5 Ma (early Pliocene). Conspicuous lateral variations in rift-related subsidence phases in the basin suggest migration of the locus of extension, and probably also changes in tectonic-transport direction during the Miocene rifting. Miocene crustal thinning in the Alboran Domain is related to low-angle intracrustal detachments and shallow normal faulting. Since the latest Tortonian, relatively uplifted and subsided areas coexist, but a generalized, continuous, and slower subsidence developed within the marine basin. Drilling results in the East and South Alboran basins (Sites 977, 978, and 979) define the timing of the later (post-Messinian) tectonic reorganization of the Alboran Basin into the present-day Alboran Sea basin. Ar/Ar dating of reworked but representative volcanic pebbles from tholeiitic, calc-alkaline, and shoshonitic series (Sites 977 and 978) constrains episodes of middle-tolate Miocene volcanism in the eastern Alboran region at 12.1 ± 0.2 Ma, 9.90 ± 0.4 Ma, 9.29 ± 0.02 Ma, and 6.1 ± 0.3 Ma. Incompatible elements in these rocks include both depleted (MORB-source) component and an ocean-island or plume-type component ("arc signature"). Calc-alkaline magmatic affinities and incompatible-element systematics were considered to support a Miocene oceanic subduction zone (from 6 Ma to at least 12 Ma) beneath the eastern Alboran region. However, these magmatic signatures prove to have also originated from variable crustal-contamination of MORB-type melts, produced by shallow melting during asthenosphere-mantle upwelling. Alternatively, modeled P-T paths in basement rocks suggest removal of mantle lithosphere below about 60 km depth (to explain further heating during decompression at shallow depth) and rapid exhumation during lithosphere stretching (4.5 km/m.y.), followed by final cooling with a minimum exhumation rate of 4 km/ m.y. It took ~9 m.y. for the exhumation of the basement rocks from 40 km depth to reach the surface at about 18 Ma, thus suggesting that extension in the Alboran Domain started at about 27 m.y. (late Oligocene), before the marine transgression occurred. We consider that strong evidence from rocks at the Site 976 basement high favors models that use the removal of mantle lithosphere as the driving force for extension generating the Alboran Basin. Further geological and geophysical data from the westernmost Mediterranean region are needed to corroborate our conclusions to define a fully satisfying model for the Neogene evolution of the lithosphere beneath the Alboran Basin. 1 Zahn, R., Comas, M.C., and Klaus, A. (Eds.), 1999. Proc. ODP, Sci. Results, 161: College Station, TX (Ocean Drilling Program).

Data from the literature are integrated in a regional Digital Elevation Model (DEM ) in order to analyse the motion of the Danakil block with regard to the Arabian and Somalian plates. The application of the poles and angles of rotation taken from the literature, induces a superposition of the Danakil block on the Arabian plate, and the formation of a gap in the Afar region. The determination of new poles of rotation using a best-fitting procedure allows one to avoid these drawbacks. In all cases, calculations are carried out keeping the Nubian plate stationary. The present approach shows that the Danakil block is an independent entity and is not related to the Nubian and Arabian plates. Between the Oligocene and the Miocene, it has been submitted to a N20°E sinistral strike-slip motion anterior to the rotation itself that was started in the middle Miocene. This rotation is directed by a mechanical couple due to the combination of the Red Sea and North Afar extensions.

The tectonic mechanisms controlling how volcanic arcs migrate through space and geologic time within dynamic subduction environments is a fundamental tectonic process that remains poorly understood. This paper presents an integrated stratigraphic and tectonic evolution of Late Cretaceous to Recent volcanic arcs and associated basins in the southeastern Caribbean Sea using seismic reflection data, wideangle seismic refraction data, well data, and onland geologic data. We propose a new tectonic model for the opening of the Grenada and Tobago basins and the 50-250-km eastward jump of arc volcanism from the Late Cretaceous Aves Ridge to the Miocene to Recent Lesser Antilles arc in the southeast Caribbean based on the mapping of three seismic megasequences. The striking similarity of the half-graben structure of the Grenada and Tobago basins that flank the Lesser Antilles arc, their similar smooth basement character, their similar deep-marine seismic facies, and their similar Paleogene sediment thickness mapped on a regional grid of seismic data suggest that the two basins formed as a single, saucer-shaped, oceanic crust Paleogene forearc basin adjacent to the now dormant Aves Ridge. This single forearc basin continued to extend and widen through flexural subsidence during the early to middle Eocene probably because of slow rollback of the subducting Atlantic oceanic slab. Rollback may have been accelerated by oblique collision of the southern Aves Ridge and southern Lesser Antilles arc with the South American continent. Uplift and growth of the southern Lesser Antilles arc divided the Grenada and Tobago basins by early to middle Miocene time. Inversion of normal faults and uplift effects along both edges of the Lesser Antilles arc are most pronounced in its southern zone of arc collision with the South American continent. The late Miocene to Recent depositional histories of the Grenada and Tobago basins are distinct because of isolation of the Grenada basin by growth and uplift of the Neogene Lesser Antilles volcanic ridge.

Bathymetric, 9.5-kHz long-range sidescan sonar (OKEAN), seismic reflection and sediment-core data are used in the analysis of two tectonic troughs south of Crete, Eastern Mediterranean Sea. Here, up to 1.2 s two-way travel time (TWTT) of strata have accumulated since the Middle Miocene in association with extension in the South Aegean region. The study area comprises >100-km- long by >25-km-wide basins filled by sediments subdivided into two seismic units: (1) an upper Unit 1 deposited in sub-basins which follow the present-day configuration of the southern Cretan margin; (2) a basal Unit 2, more than 500 ms (TWTT) thick, accumulated in deeper half-graben/grabens distinct from the present-day depocentres. Both units overlap a locally stratified Unit 3 comprising the pre-Neogene core complex of Crete and Gavdos. In this work, the interpreted seismic units are correlated with the onshore stratigraphy, demonstrating that denudation processes occurring on Crete and Gavdos in response to major tectonic events have been responsible for high sedimentation rates along the proximal southern Cretan margin. Consequently, topographically confined sedimentary units have been deposited south of Crete in the last 12 Ma, including turbidites and other mass-flow deposits fed by evolving transverse and axial channel systems. Surface processes controlling facies distribution include the direct inflow of sediment from alluvial-fan systems and incising mountain rivers onto the Cretan slope, where significant sediment instability processes occur at present. In this setting, seismic profiles reveal eight different types of stratigraphic contacts on basin-margin highs, and basinal areas show evidence of halokinesis and/or fluid escape. The acquired data also show that significant changes to the margin’s configuration occurred in association with the post-Alpine tectonic and eustatic episodes affecting the Eastern Mediterranean.

The Gunung Sewu area of South Central Java, Indonesia during Mid Miocene, Langhian-Serravallian (Tf1-Tf2), was deposited in a large area of warm, very shallow-marine water. Coralline algae and abundant larger benthic foraminifera dominate the carbonate lithologies. Larger benthic foraminifera from previously unstudied sections in South Central Java are described and figured. They have led to an understanding of sequence stratigraphic and facies relationship of Miocene carbonates in Indonesia. Thirteen larger foraminifera species are described and illustrated. A detailed biostratigraphical studies of The phylogeny Katacycloclypeus annulatus -K. martini and the gradual evolution from Austrotrillina asmariensis into A. howchini are recognised. Analysis of the larger benthic foraminifera has allowed accurate dating of the carbonate sections studied using the East Indian Letter Classification.

A quantitative paleobathymetric study of Badenian foraminifera was carried out from Tekeres-1 and Tengelic-2 boreholes, north of the Mecsek Mts., SW Hungary. Paleobathymetric data, based on plankton/benthos ratio provided input for the analysis of the subsidence history. The biostratigraphic framework is mainly provided by calcareous nannoplankton (zones NN5–NN7). Changes in sedimentation rates are also considered, partly calculated from number of benthos per unit sediment, and partly estimated from the changes of lithofacies. Relative sea-level changes are calculated from changes of paleowater depth and coeval sedimentary thickness. The result is examined as the sum of accommodation space created by subsidence and eustasy. In that period of time eustatic changes were about an order of magnitude smaller than changes created by movements of the basin floor. According to our model in early Badenian (up to the half of NN5 nannozone) a very rapid transtension-related subsidence of about 500 m occurred. This was interrupted by a short period of uplift of minor magnitude at about the first third of NN5 zone; thereafter, subsidence continued and the basin floor reached its deepest position. Still within the NN5 nannozone (Early Badenian) a significant uplift occurred, terminating the life of the deep basin. The Late Badenian (NN6) is characterized by a relatively small rate of subsidence and presumably quiet tectonism. During this period bathymetric changes are thought to be controlled primarily by eustatic changes. The first uplift – only interrupting subsidence – is regarded as the result of the change of the local stress field because of convergence along the curvature of strike slip faults. The second uplift, which stopped the subsidence of the basin floor is thought to be of a regional character and is attributed to the compression generated between Tisza and Alcapa tectonic units.

A new species of fossil hominoid is described from the middle Miocene deposits at Pas xalar, Turkey. It is the less common of the two Pas xalar species discussed by , making up approximately 10% of the individuals in the Pas xalar hominoid sample according to analyses of the minimum number of individuals. To the diagnostic features of I 1 described by and can now be added further diagnostic features of all the anterior teeth, as well as both upper premolars and P 3 . These include discrete, nonmetric features and metric differences at all the noted tooth positions. Attempts to distinguish the upper and lower molars of the two species have so far been unsuccessful, with the possible exception of M 3 . The morphology of the new species is similar in most respects to that of Kenyapithecus wickeri from Fort Ternan, especially concerning maxillary morphology. They share robust and moderately deep maxillary alveolar processes, a restricted maxillary sinus with an elevated and uncomplicated floor, lacking the compartmentalization evident to varying degrees in many other taxa, and a zygomatic process that originates and turns laterally fairly high above the alveolar margin. There are also a number of distinctive similarities in the dentition, particularly for I 1 , C 1 , P 4 and P 3 . The I 1 morphology in particular, with greatly hypertrophied lingual marginal ridges bounding a uniformly thickened basal crown area, is distinctive among Miocene hominoids. All of these similarities serve to reinforce the differences noted by others between the derived morphology of K. wickeri and the more primitive morphology of Equatorius africanus from Maboko and Kipsaramon. The new species differs from K. wickeri in morphological details of most of the anterior and premolar teeth that are known for both species, despite the general morphological similarity, and in the size of I 1 versus I 2 . One striking feature of the new species is a relatively large incisive fossa, although it cannot be determined if this is associated with an open palatine fenestra, as in many early Miocene hominoids, or a minimally overlapping palate and nasoalveolar clivus, as in some middle and late Miocene hominoids.

Pliocene and Quaternary tectonic structures mainly consisting of segmented northwest-southeast normal faults, and associated seismicity in the central Betics do not agree with the transpressive tectonic nature of the Africa-Eurasia plate boundary in the Ibero-Maghrebian region. Active extensional deformation here is heterogeneous, individual segmented normal faults being linked by relay ramps and transfer faults, including oblique-slip and both dextral and sinistral strike-slip faults. Normal faults extend the hanging wall of an extensional detachment that is the active segment of a complex system of successive WSW-directed extensional detachments which have thinned the Betic upper crust since middle Miocene. Two areas, which are connected by an active 40-km long dextral strike-slip transfer fault zone, concentrate present-day extension. Both the seismicity distribution and focal mechanisms agree with the position and regime of the observed faults. The activity of the transfer zone during middle Miocene to present implies a mode of extension which must have remained substantially the same over the entire period. Thus, the mechanisms driving extension should still be operating. Both the westward migration of the extensional loci and the high asymmetry of the extensional systems can be related to edge delamination below the south Iberian margin coupled with roll-back under the Alborán Sea; involving the asymmetric westward inflow of asthenospheric material under the margins.

Most of the 29 living species of Potamididae show a close association with mangroves. The trees provide the snails with shelter, protection from predators, a solid substrate and sometimes food. Using sequences from three genes (nuclear 18S rRNA and 28S rRNA, mitochondrial COI) we derive a molecular phylogeny and recognize six living genera (Terebralia, Telescopium, Tympanotonos, Cerithidea, Cerithideopsis, Cerithideopsilla). The oldest modern genera (Terebralia, Cerithideopsis) appeared in the Tethyan realm in the Middle Eocene, shortly after the origin of mangrove trees. Whereas most potamidid genera are now restricted to either the Indo-West Pacific (IWP) or to the eastern Pacific plus Atlantic (EPA), sister clades of Cerithideopsis survive in both realms. Based on a reinterpretation of the fossil record (particularly of the monotypic Tympanotonos and extinct Potamides), and parsimonious reconstruction of ancestral habitats, we suggest that the living potamidids are an adaptive radiation that has always been closely associated with mangroves. The specialized tree-climbing groups Cerithidea and Cerithideopsis were independently derived from mud-dwelling ancestors. Cerithideopsilla cingulata (a species complex in the IWP) and 'Potamides' conicus (in the Mediterranean and Indian Ocean) form a single clade within the genus Cerithideopsilla. This refutes the hypothesis that 'P.' conicus is the sole relict of the Tethyan Potamides that has occurred in the Mediterranean region since the Palaeocene. Instead, the phylogeny and fossil record suggest that an ancestor of Cerithideopsilla conica with planktotrophic larvae dispersed from the IWP to the Mediterranean in the Middle Miocene, that its direct development evolved in the Mediterranean during the Pliocene, and that it reinvaded the Indian Ocean during the Plio-Pleistocene.

Messinian evaporites, which resulted from the salinity crisis during the final closure of the Mediterranean Sea, are exposed in SE Turkey. These evaporites formed in two isolated sub-basins, Iskenderun-Arsuz (IA) and Hatay-Samandağ (HS), which belong to different depositional configurations and tectonic structures. The Neogene fill of these sub-basins consists of a thick sedimentary succession that started with Early Miocene terrestrial clastics, followed by reefs (Middle Miocene) and shallow water siliciclastics (Tortonian - Early to Late Miocene) and finally Messinian evaporates. These sub-basins accumulated in a diverse range of depositional environments from very shallow to deeper water. Evaporite facies in the IA sub-basin consist of sabkhas, saline lagoons and ponds. They are mainly represented by chemical deposits such as scattered gypsum nodules and balls, nodular bedded gypsum, laminated gypsum (Type-A) and selenites (Type-S1). Evaporites in the HS sub-basin mainly consist of detrital gypsum composed of gypsum laminae (Type-B, C), gypsum arenite-rudites and deeper water selenites (≤ 20 m), and resedimented selenites (Type-S2), which were deposited on a sulfate platform with a slope-basin transitional zone. Secondary gypsum with alabastrine and porphyroblastic textures as well as satin spar veins is commonly associated with the sabkha-type evaporites of the IA sub-basin. Deeper-water clastic evaporites of the HS sub-basin have generally remained as primary gypsum or have only been slightly affected by diagenetic alterations. The isotope values ( 87/86Sr; δ 18O SMOW; and δ 34S CDT) from the different kinds of gypsum lithofacies of the sub-basin are similar to those of the Messinian evaporites in other peri-Mediterranean basins, indicating an origin from marine water without external or basinal contributions. The Messinian evaporites examined in this paper are overlain by Early Pliocene (Zanclean) deposits composed of shallow- and deep-water siliciclastics and carbonates with local intercalations of Lago-Mare-type strata. Throughout the Messinian evaporitic stage, the IA sub-basin was mainly comprised of shallow water evaporites, while the HS sub-basin underwent deepening related to regional tectonics induced by the Dead Sea Fault during the construction of the Hatay Graben.

Coupled analysis of the pressure-temperature (PT) evolution and accessory phase geochronology of a single sample reveals the burial-uplift history of part of the Lesser Himalaya during the Middle Miocene. Phase-equilibria calculations indicate that a peak temperature of 600-640°C followed burial to approximately 25 km depth. Laser-ablation monazite geochronology yields a weighted mean 206 Pb ⁎ / 238 U age of 11.1 ± 2.0 Ma and a Tera-Wasserburg Concordia intercept age of 10.6 ± 0.9 Ma, with no distinguishable age difference between matrix and inclusion grains. Considerations of the likelihood of excess 206 Pb further suggest that the crystallization age lies in the range 9-10 Ma. Textural analysis suggests that monazite grew during prograde metamorphism. Peak metamorphic conditions were followed by exhumation and cooling, forming a distinctively tight PT path closure. Both the shape of this path and its relatively young prograde phase distinguish Lesser Himalayan evolution from that typically inferred for the High Himalaya, and allow exploration of the thermal mechanisms that operated in the western Himalaya during the interval ca. 23-6 Ma. The PTt history is characteristic of footwall heating due to rapid overthrusting of hot rock (the Higher Himalaya), followed by incorporation into a thrust sheet that exhumed the sequence rapidly enough to preserve an inverted metamorphic gradient.