cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.3454370
title: Early and Middle Miocene dinoflagellate cyst stratigraphy of the Central Paratethys, Central Europe

description: Marine organic-walled dinoflagellate cysts have been studied from the Early and Middle Miocene of the Central Paratethys in Austria (Vienna and eastern Alpine Foreland basins) and Hungary (Pannonian Basin), and compared with assemblages of similar age from the Atlantic Ocean and Mediterranean Sea. The presence of a diverse flora of 71 taxa, including such biostratigraphical markers as <em>Apteodinium spiridoides</em>, <em>Cerebrocysta poulsenii</em>, <em>Cordosphaeridium cantharellus</em>, <em>Cribroperidinium tenuitabulatum</em>, <em>Exochosphaeridium insigne</em>, <em>Glaphyrocysta reticulosa</em> s.l., <em>Habibacysta tectata</em>, <em>Labyrinthodinium truncatum</em> subsp. <em>truncatum</em>, <em>Palaeocystodinium miocaenicum</em>, and <em>Unipontidinium aquaeductus</em>, has allowed the establishment of five biozones that characterize the Ottnangian, Badenian and Sarmatian local stages (collectively equivalent to the mid-Burdigalian, upper Langhian and Serravallian stages). This is the first study to demonstrate the applicability of dinoflagellate cysts for detailed stratigraphic correlation and palaeoenvironmental interpretation in the Early and Middle Miocene of the Central Paratethys area.
DOI: 10.6084/m9.figshare.3454370.v1
title: Early and Middle Miocene dinoflagellate cyst stratigraphy of the Central Paratethys, Central Europe

description: Marine organic-walled dinoflagellate cysts have been studied from the Early and Middle Miocene of the Central Paratethys in Austria (Vienna and eastern Alpine Foreland basins) and Hungary (Pannonian Basin), and compared with assemblages of similar age from the Atlantic Ocean and Mediterranean Sea. The presence of a diverse flora of 71 taxa, including such biostratigraphical markers as <em>Apteodinium spiridoides</em>, <em>Cerebrocysta poulsenii</em>, <em>Cordosphaeridium cantharellus</em>, <em>Cribroperidinium tenuitabulatum</em>, <em>Exochosphaeridium insigne</em>, <em>Glaphyrocysta reticulosa</em> s.l., <em>Habibacysta tectata</em>, <em>Labyrinthodinium truncatum</em> subsp. <em>truncatum</em>, <em>Palaeocystodinium miocaenicum</em>, and <em>Unipontidinium aquaeductus</em>, has allowed the establishment of five biozones that characterize the Ottnangian, Badenian and Sarmatian local stages (collectively equivalent to the mid-Burdigalian, upper Langhian and Serravallian stages). This is the first study to demonstrate the applicability of dinoflagellate cysts for detailed stratigraphic correlation and palaeoenvironmental interpretation in the Early and Middle Miocene of the Central Paratethys area.
DOI: 10.6084/m9.figshare.3454367
title: Oligocene-Miocene middle crustal flow in southern Tibet: geochronology of Mabja Dome

description: New U-Pb zircon, monazite, <sup>40</sup>Ar/<sup>39</sup>Ar, and apatite fission track ages provide constraints on the timing of formation and exhumation of the Mabja Dome, southern Tibet, shed light on how this gneiss dome formed, and provide important clues on the tectonic evolution of middle crustal rocks in southern Tibet. Zircons from a deformed leucocratic dyke swarm yield a U-Pb age of 23.1 ± 0.8 Ma, providing the first age constraint on the timing of middle crustal ductile horizontal extension in the North Himalayan gneiss domes. Zircons and monazite from a post-tectonic two-mica granite yield ages of 14.2 ± 0.2 Ma and 14.5 ± 0.1, respectively, indicating that vertical thinning and subhorizontal stretching had ceased by the middle Miocene. Mica <sup>40</sup>Ar/<sup>39</sup>Ar ages from schists and orthogneisses increase structurally down-section from 12.85 ± 0.13 Ma to 17.0 ± 0.19 Ma and then decrease at the deepest structural levels to 13.29 ± 0.09 Ma. Micas from the leucocratic dyke swarm and post-tectonic two-mica granites yield similar <sup>40</sup>Ar/<sup>39</sup>Ar cooling ages of 13.48 ± 0.13 to 12.84 ± 0.08 Ma. The low-temperature steps of potassium feldspar <sup>40</sup>Ar/<sup>39</sup>Ar spectra yield ages of <em>c.</em> 11.0–12.5 Ma and apatite fission track analyses indicate the dome uniformly cooled below <em>c.</em> 115°C at 9.5 ± 0.6 Ma. Based on these data, calculated average cooling rates across the dome range from <em>c.</em> 40–60°C/million years in schist and orthogneiss and following emplacement of the leucocratic dyke swarm, to <em>c.</em> 350°C/million years following emplacement of the two-mica granites. The mylonitic foliation, peak metamorphic isograds, and mica <sup>40</sup>Ar/<sup>39</sup>Ar chrontours are domed, whereas the low-temperature step potassium feldspar <sup>40</sup>Ar/<sup>39</sup>Ar and apatite fission track chrontours are not, suggesting that doming occurred between 13.0 and 12.5 Ma and at temperatures between 370 and 200°C. Our new ages, along with field, structural and metamorphic data, indicate that the domal geometry observed at Mabja developed by middle-Miocene southward-directed thrust faulting upward and southward along a north-dipping ramp above cold Tethyan sediments. The structural, metamorphic and geochronologic histories documented at Mabja Dome are similar to those of Kangmar Dome, suggesting a common mode of occurrence of these events throughout southern Tibet. Vertical thinning and horizontal stretching, metamorphism, generation of migmatites, and emplacement of leucogranites in the domes of southern Tibet are synchronous with similar events in the Greater Himalayan Sequence that underlie the high Himalaya. These relations are consistent with previously proposed models for a ductile middle-crustal channel bounded above by the South Tibetan detachment system and below by the Main Central thrust in the High Himalaya that extended northward beneath southern Tibet.
DOI: 10.6084/m9.figshare.3454367.v1
title: Oligocene-Miocene middle crustal flow in southern Tibet: geochronology of Mabja Dome

description: New U-Pb zircon, monazite, <sup>40</sup>Ar/<sup>39</sup>Ar, and apatite fission track ages provide constraints on the timing of formation and exhumation of the Mabja Dome, southern Tibet, shed light on how this gneiss dome formed, and provide important clues on the tectonic evolution of middle crustal rocks in southern Tibet. Zircons from a deformed leucocratic dyke swarm yield a U-Pb age of 23.1 ± 0.8 Ma, providing the first age constraint on the timing of middle crustal ductile horizontal extension in the North Himalayan gneiss domes. Zircons and monazite from a post-tectonic two-mica granite yield ages of 14.2 ± 0.2 Ma and 14.5 ± 0.1, respectively, indicating that vertical thinning and subhorizontal stretching had ceased by the middle Miocene. Mica <sup>40</sup>Ar/<sup>39</sup>Ar ages from schists and orthogneisses increase structurally down-section from 12.85 ± 0.13 Ma to 17.0 ± 0.19 Ma and then decrease at the deepest structural levels to 13.29 ± 0.09 Ma. Micas from the leucocratic dyke swarm and post-tectonic two-mica granites yield similar <sup>40</sup>Ar/<sup>39</sup>Ar cooling ages of 13.48 ± 0.13 to 12.84 ± 0.08 Ma. The low-temperature steps of potassium feldspar <sup>40</sup>Ar/<sup>39</sup>Ar spectra yield ages of <em>c.</em> 11.0–12.5 Ma and apatite fission track analyses indicate the dome uniformly cooled below <em>c.</em> 115°C at 9.5 ± 0.6 Ma. Based on these data, calculated average cooling rates across the dome range from <em>c.</em> 40–60°C/million years in schist and orthogneiss and following emplacement of the leucocratic dyke swarm, to <em>c.</em> 350°C/million years following emplacement of the two-mica granites. The mylonitic foliation, peak metamorphic isograds, and mica <sup>40</sup>Ar/<sup>39</sup>Ar chrontours are domed, whereas the low-temperature step potassium feldspar <sup>40</sup>Ar/<sup>39</sup>Ar and apatite fission track chrontours are not, suggesting that doming occurred between 13.0 and 12.5 Ma and at temperatures between 370 and 200°C. Our new ages, along with field, structural and metamorphic data, indicate that the domal geometry observed at Mabja developed by middle-Miocene southward-directed thrust faulting upward and southward along a north-dipping ramp above cold Tethyan sediments. The structural, metamorphic and geochronologic histories documented at Mabja Dome are similar to those of Kangmar Dome, suggesting a common mode of occurrence of these events throughout southern Tibet. Vertical thinning and horizontal stretching, metamorphism, generation of migmatites, and emplacement of leucogranites in the domes of southern Tibet are synchronous with similar events in the Greater Himalayan Sequence that underlie the high Himalaya. These relations are consistent with previously proposed models for a ductile middle-crustal channel bounded above by the South Tibetan detachment system and below by the Main Central thrust in the High Himalaya that extended northward beneath southern Tibet.
DOI: 10.6084/m9.figshare.3454364
title: Chronology of the Middle-Upper Pliocene succession in the Strongoli area: constraints on the geological evolution of the Crotone Basin (Southern Italy)

description: The aim of this study is to reconstruct the evolution of the Strongoli area, a critical sector of the Crotone Basin (Calabria, Southern Italy), where a thick Middle-Upper Pliocene marine succession is present. The Strongoli succession shows prominent changes in the sedimentary environment that are partly forced by tectonics. Major tectonostratigraphic events have been recognized that might correlate with spreading pulses in the back-arc Tyrrhenian Sea. In particular, we demonstrate that a dramatic basinal collapse at <em>c.</em> 2.3 Ma correlates with the so-called ‘Calabrian transgression’ <em>Auctorum</em> and is close in age to the oceanization of the Marsili Basin.
DOI: 10.6084/m9.figshare.3454364.v1
title: Chronology of the Middle-Upper Pliocene succession in the Strongoli area: constraints on the geological evolution of the Crotone Basin (Southern Italy)

description: The aim of this study is to reconstruct the evolution of the Strongoli area, a critical sector of the Crotone Basin (Calabria, Southern Italy), where a thick Middle-Upper Pliocene marine succession is present. The Strongoli succession shows prominent changes in the sedimentary environment that are partly forced by tectonics. Major tectonostratigraphic events have been recognized that might correlate with spreading pulses in the back-arc Tyrrhenian Sea. In particular, we demonstrate that a dramatic basinal collapse at <em>c.</em> 2.3 Ma correlates with the so-called ‘Calabrian transgression’ <em>Auctorum</em> and is close in age to the oceanization of the Marsili Basin.
DOI: 10.6084/m9.figshare.3454361
title: First results from the CROP-11 deep seismic profile, central Apennines, Italy: evidence of mid-crustal folding

description: The CROP-11 deep seismic profile across the central Apennines, Italy, reveals a previously unknown, mid-crustal antiform here interpreted as a fault-bend fold-like structure. The seismic facies and gravity signature suggest that this structure consists of low-grade metamorphic rocks. Geomorphological, stratigraphic and tectonic evidence in the overlying shallow thrusts suggests that this structure developed in early to mid-Messinian time and grew out of sequence in late Messinian–Pliocene time. The out-of-sequence growth may reflect a taper subcriticality stage of the Apenninic thrust wedge, which induced renewed contraction in the rear.
DOI: 10.6084/m9.figshare.3454361.v1
title: First results from the CROP-11 deep seismic profile, central Apennines, Italy: evidence of mid-crustal folding

description: The CROP-11 deep seismic profile across the central Apennines, Italy, reveals a previously unknown, mid-crustal antiform here interpreted as a fault-bend fold-like structure. The seismic facies and gravity signature suggest that this structure consists of low-grade metamorphic rocks. Geomorphological, stratigraphic and tectonic evidence in the overlying shallow thrusts suggests that this structure developed in early to mid-Messinian time and grew out of sequence in late Messinian–Pliocene time. The out-of-sequence growth may reflect a taper subcriticality stage of the Apenninic thrust wedge, which induced renewed contraction in the rear.
DOI: 10.6084/m9.figshare.3454358
title: Provenance of Cambrian conglomerates from New Zealand: implications for the tectonomagmatic evolution of the SE Gondwana margin

description: The oldest rocks in New Zealand are the Mid- to Late Cambrian intra-oceanic island arc rocks of the Takaka terrane (Devil River arc). The provenance of Cambrian conglomerates stratigraphically above the exposed arc succession was studied to constrain the late stages of arc evolution and its accretion to continental crust. The Dead Goat Conglomerate contains two distinct groups of igneous clasts: (1) intermediate to felsic volcanic clasts with moderately enriched light rare earth element (LREE) and high field strength element (HFSE) contents and positive ϵNd<sub>500</sub> (+2.1) that were derived from a medium-K calc-alkaline source, probably the main sequence of the Devil River arc; (2) dioritic to metagranitic plutonic clasts strongly enriched in LREE and HFSE and with ϵNd<sub>500</sub> of +3.5 to +5.9 that were derived from a high-K arc source, probably the uppermost units of the Devil River arc. This is consistent with a new U–Pb sensitive high-resolution ion microprobe age of 496 ± 6 Ma. The Lockett Conglomerate also contains two distinct groups of igneous clasts: (1) ultramafic to intermediate igneous clasts identified as boninitic to transitional low-K calc-alkaline arc-related rocks based on depleted REE and HFSE abundances; (2) ‘I’-type metagranitoid clasts derived from a distinct Andean type continental margin, as indicated by ϵNd<sub>500</sub> as low as −7.1. Both conglomerates contain sandstone clasts derived from a common old, multi-cycle continental source with ϵNd<sub>500</sub> of −14.2 to −15.7, and no suitable source has been found in present-day New Zealand. The new provenance data from these conglomerates constrain the time of accretion of the Devil River arc to the palaeo-Pacific Gondwana margin and provide new information on the structural evolution of the accretionary event.
DOI: 10.6084/m9.figshare.3454358.v1
title: Provenance of Cambrian conglomerates from New Zealand: implications for the tectonomagmatic evolution of the SE Gondwana margin

description: The oldest rocks in New Zealand are the Mid- to Late Cambrian intra-oceanic island arc rocks of the Takaka terrane (Devil River arc). The provenance of Cambrian conglomerates stratigraphically above the exposed arc succession was studied to constrain the late stages of arc evolution and its accretion to continental crust. The Dead Goat Conglomerate contains two distinct groups of igneous clasts: (1) intermediate to felsic volcanic clasts with moderately enriched light rare earth element (LREE) and high field strength element (HFSE) contents and positive ϵNd<sub>500</sub> (+2.1) that were derived from a medium-K calc-alkaline source, probably the main sequence of the Devil River arc; (2) dioritic to metagranitic plutonic clasts strongly enriched in LREE and HFSE and with ϵNd<sub>500</sub> of +3.5 to +5.9 that were derived from a high-K arc source, probably the uppermost units of the Devil River arc. This is consistent with a new U–Pb sensitive high-resolution ion microprobe age of 496 ± 6 Ma. The Lockett Conglomerate also contains two distinct groups of igneous clasts: (1) ultramafic to intermediate igneous clasts identified as boninitic to transitional low-K calc-alkaline arc-related rocks based on depleted REE and HFSE abundances; (2) ‘I’-type metagranitoid clasts derived from a distinct Andean type continental margin, as indicated by ϵNd<sub>500</sub> as low as −7.1. Both conglomerates contain sandstone clasts derived from a common old, multi-cycle continental source with ϵNd<sub>500</sub> of −14.2 to −15.7, and no suitable source has been found in present-day New Zealand. The new provenance data from these conglomerates constrain the time of accretion of the Devil River arc to the palaeo-Pacific Gondwana margin and provide new information on the structural evolution of the accretionary event.
DOI: 10.6084/m9.figshare.3454355
title: Provenance of late Palaeozoic metasediments of the SW South American Gondwana margin: a combined U–Pb and Hf-isotope study of single detrital zircons

description: Combined U–Pb and Lu–Hf isotope measurements of single detrital zircon grains in Carboniferous metasediments from Patagonia delineate the source areas of the sediments. The detritus, represented by four metasandstone samples, was deposited prior to onset of subduction in Late Carboniferous time along the south Patagonian proto-Pacific Gondwana margin. A broad series of detrital zircon age peaks (0.35–0.7 Ga, 0.9–1.5 Ga) and a large spread (0.3–3.5 Ga) in the age spectra require numerous sources. A fifth metasediment was deposited after the onset of subduction. This syncollisional sample shows two distinct U–Pb age peaks at <em>c</em>. 290 Ma and 305 Ma. This points to a few sources only (Patagonia, West Antarctica). Initial Hf-isotope compositions of selected U–Pb dated zircons from the Carboniferous metasediments reveal zircon protoliths originating from both recycled crust and juvenile sources (εHf<sub>(T=0.4–3.5Ga)</sub>=−14 to +12). A comparison with crustal compositions of possible source areas indicates that the detritus mainly originated from the interior of Gondwana (Extra-Andean Patagonia, the Argentine Sierra de la Ventana, southernmost Africa, East Antarctica), as well as northern Chile and northwestern Argentina. The sediment transportation paths are consistent with an autochthonous palaeogeographical position of Patagonia with respect to Gondwana in Carboniferous time.
DOI: 10.6084/m9.figshare.3454352
title: Age constraints for the thermal evolution and erosional history of the central European Variscan belt: new data from the sediments and basement of the Carboniferous foreland basin in western Poland

description: Three Carboniferous-age detrital muscovites from the Variscan foreland basin of SW Poland and two muscovites from phyllites underlying the basement have been dated by the <sup>40</sup>Ar/<sup>39</sup>Ar step-heating and single-crystal laser fusion method. <sup>40</sup>Ar/<sup>39</sup>Ar analysis of the detrital micas defines step-heating preferred ages of 370.7 ± 1.4, 363.0 ± 1.9 and 355.0 ± 1.3 Ma. Single-crystal laser fusion data indicate little dispersion for the first of three samples, with an integrated age that closely matches the step-heating data, but the latter two describe inhomogeneous populations. The white mica concentrate from one phyllite yields a step-heating preferred age of 358.6 ± 1.8 Ma. The second phyllite sample displays an incremental discordant apparent age spectrum representing a mixture of white mica grains of varying ages. Our most important finding is that the Variscan foreland basin was supplied by source rocks that were exhumed and cooled in the Late Devonian, probably as a result of an early Variscan collisional event, previously largely undocumented. Although accessible exposures of the Variscan basement in SW Poland exhibit only a minor component of rocks exhumed before the Carboniferous, our work suggests that large tracts of rocks with a Devonian cooling signature are preserved at depth beneath the foreland basin.
DOI: 10.6084/m9.figshare.3454352.v1
title: Age constraints for the thermal evolution and erosional history of the central European Variscan belt: new data from the sediments and basement of the Carboniferous foreland basin in western Poland

description: Three Carboniferous-age detrital muscovites from the Variscan foreland basin of SW Poland and two muscovites from phyllites underlying the basement have been dated by the <sup>40</sup>Ar/<sup>39</sup>Ar step-heating and single-crystal laser fusion method. <sup>40</sup>Ar/<sup>39</sup>Ar analysis of the detrital micas defines step-heating preferred ages of 370.7 ± 1.4, 363.0 ± 1.9 and 355.0 ± 1.3 Ma. Single-crystal laser fusion data indicate little dispersion for the first of three samples, with an integrated age that closely matches the step-heating data, but the latter two describe inhomogeneous populations. The white mica concentrate from one phyllite yields a step-heating preferred age of 358.6 ± 1.8 Ma. The second phyllite sample displays an incremental discordant apparent age spectrum representing a mixture of white mica grains of varying ages. Our most important finding is that the Variscan foreland basin was supplied by source rocks that were exhumed and cooled in the Late Devonian, probably as a result of an early Variscan collisional event, previously largely undocumented. Although accessible exposures of the Variscan basement in SW Poland exhibit only a minor component of rocks exhumed before the Carboniferous, our work suggests that large tracts of rocks with a Devonian cooling signature are preserved at depth beneath the foreland basin.
DOI: 10.6084/m9.figshare.3454349
title: The effect of broadleaved woodland on Chalk groundwater resources

description: The impact of broadleaved woodland on chalk groundwater resources, in Hampshire, UK, was assessed with a comparative study of beech woodland at Black Wood near Micheldever and grass at Bridgets Farm near Winchester. At both sites, parallel estimates of evaporation and detailed studies of the changes in soil water content and the direction of water movement were made. Beneath both sites, a reduction in soil water content was observed during the summer to a depth of 6 m. However, total water potential measurements showed that upward movement of water was only occurring in the upper 2 m of the profile, whilst drainage was occurring below this point. Drainage continued even when soil moisture deficits existed in the upper part of the profile. Seasonal differences between woodland and grass do exist, however annual differences in evaporation and drainage are insignificant. The similarity of evaporation from and drainage below the broadleaved woodland and grass sites contrasts markedly with several other studies that show greater drying below woodland. Unlike other comparisons, this study was made within a large block of woodland and both sites were on chalk. The relevance of woodland size and chalk substrate are discussed.
DOI: 10.6084/m9.figshare.3454349.v1
title: The effect of broadleaved woodland on Chalk groundwater resources

description: The impact of broadleaved woodland on chalk groundwater resources, in Hampshire, UK, was assessed with a comparative study of beech woodland at Black Wood near Micheldever and grass at Bridgets Farm near Winchester. At both sites, parallel estimates of evaporation and detailed studies of the changes in soil water content and the direction of water movement were made. Beneath both sites, a reduction in soil water content was observed during the summer to a depth of 6 m. However, total water potential measurements showed that upward movement of water was only occurring in the upper 2 m of the profile, whilst drainage was occurring below this point. Drainage continued even when soil moisture deficits existed in the upper part of the profile. Seasonal differences between woodland and grass do exist, however annual differences in evaporation and drainage are insignificant. The similarity of evaporation from and drainage below the broadleaved woodland and grass sites contrasts markedly with several other studies that show greater drying below woodland. Unlike other comparisons, this study was made within a large block of woodland and both sites were on chalk. The relevance of woodland size and chalk substrate are discussed.