cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.3454007.v1
title: Talas–Fergana Fault Cenozoic timing of deformation and its relation to Pamir indentation

description: Regional strike-slip faults are widely distributed in continental interiors and play a major role in the distribution of far-field deformation due to continental collisions. Constraining the deformation history of the Talas–Fergana Fault (TFF), one of the largest of such faults in the Himalayan deformed interior, is vital to comprehend the hinterland kinematics of the India–Asia collision. New apatite fission track results from the NW Tien Shan define a rapid exhumation event at <em>c.</em> 25 Ma. This event is correlated with a synchronous pulse in the South Tien Shan, implying that both ranges experienced a simultaneous onset of rapid exhumation. We suggest that strike-slip motion along the TFF commenced at <em>c.</em> 25 Ma, facilitating counter-clockwise rotation of the Fergana Basin and enabling exhumation of the linked horsetail splays. Pamir indentation, located south of the Western Tien Shan, is postulated to be underway by <em>c.</em> 20 Ma. Recently published results suggest synchronous strike-slip deformation in the western Tarim Basin and eastern flank of the Pamir. Based on our results and published data, we are able to connect Tarim and Pamir deformation to the onset of TFF slip. We suggest that this pre-existing regional structure was responsible for transferring Pamir-induced shortening to the NW Tien Shan.
DOI: 10.6084/m9.figshare.3454001
title: The Fezouata fossils of Morocco; an extraordinary record of marine life in the Early Ordovician

description: The discovery of the Fezouata biota in the latest Tremadocian of southeastern Morocco has significantly changed our understanding of the early Phanerozoic radiation. The shelly fossil record shows a well-recognized pattern of macroevolutionary stasis between the Cambrian Explosion and the Great Ordovician Biodiversification Event, but the rich soft-bodied Fezouata biota paints a different evolutionary picture. The Fezouata assemblage includes a considerable component of Cambrian holdovers alongside a surprising number of crown group taxa previously unknown to have evolved by the Early Ordovician. Study of the Fezouata biota is in its early stages, and future discoveries will continue to enrich our view of the dynamics of the early Phanerozoic radiation and of the nature of the fossil record.
DOI: 10.6084/m9.figshare.3454001.v1
title: The Fezouata fossils of Morocco; an extraordinary record of marine life in the Early Ordovician

description: The discovery of the Fezouata biota in the latest Tremadocian of southeastern Morocco has significantly changed our understanding of the early Phanerozoic radiation. The shelly fossil record shows a well-recognized pattern of macroevolutionary stasis between the Cambrian Explosion and the Great Ordovician Biodiversification Event, but the rich soft-bodied Fezouata biota paints a different evolutionary picture. The Fezouata assemblage includes a considerable component of Cambrian holdovers alongside a surprising number of crown group taxa previously unknown to have evolved by the Early Ordovician. Study of the Fezouata biota is in its early stages, and future discoveries will continue to enrich our view of the dynamics of the early Phanerozoic radiation and of the nature of the fossil record.
DOI: 10.6084/m9.figshare.3453998
title: Anisotropy of magnetic susceptibility (AMS) records synsedimentary deformation kinematics at Pico del Aguila anticline, Pyrenees, Spain

description: Pico del Aguila anticline is a transverse décollement fold located at the Pyrenean thrust front. The anticline is a synsedimentary structure buried during growth by delta front mudstones and sands of the Eocene Arguis and Belsué-Atares formations. Both the anisotropy of magnetic susceptibility measured at 77 K and 294 K and the anisotropy of anhysteretic remanence show that susceptibility is dominated by paramagnetic clay minerals and can be used as a proxy for depositional and tectonic fabric orientations. In general, the maximum and intermediate principal susceptibilities (<em>k</em><sub>1</sub> and <em>k</em><sub>2</sub>) of the AMS lie in bedding and the minimum principal susceptibility (<em>k</em><sub>3</sub>) is oriented nearly normal to bedding. Layer-parallel shortening (LPS) produced a <em>c.</em> north–south-trending magnetic intersection lineation in bedding on anticline limbs and in the adjacent Belsué and Arguis synclines by deforming the depositional and diagenetic compaction fabric. The degree of magnetic anisotropy is higher along axial surfaces than on limbs. At the anticline hinge, oblate magnetic ellipsoids with an east–west-aligned lineation and a bedding-parallel magnetic foliation demonstrate the overprinting of the LPS magnetic fabric during the emplacement of the underlying thrust sheet. AMS data record fold kinematics characterized by constant-length limb rotation about pinned hinges and are compatible with kinematics recorded by growth strata geometries. This study emphasizes that AMS is a very sensitive measure of depositional, compaction and tectonic fabrics in marine clastic rocks in the diagenetic realm.
DOI: 10.6084/m9.figshare.3453998.v1
title: Anisotropy of magnetic susceptibility (AMS) records synsedimentary deformation kinematics at Pico del Aguila anticline, Pyrenees, Spain

description: Pico del Aguila anticline is a transverse décollement fold located at the Pyrenean thrust front. The anticline is a synsedimentary structure buried during growth by delta front mudstones and sands of the Eocene Arguis and Belsué-Atares formations. Both the anisotropy of magnetic susceptibility measured at 77 K and 294 K and the anisotropy of anhysteretic remanence show that susceptibility is dominated by paramagnetic clay minerals and can be used as a proxy for depositional and tectonic fabric orientations. In general, the maximum and intermediate principal susceptibilities (<em>k</em><sub>1</sub> and <em>k</em><sub>2</sub>) of the AMS lie in bedding and the minimum principal susceptibility (<em>k</em><sub>3</sub>) is oriented nearly normal to bedding. Layer-parallel shortening (LPS) produced a <em>c.</em> north–south-trending magnetic intersection lineation in bedding on anticline limbs and in the adjacent Belsué and Arguis synclines by deforming the depositional and diagenetic compaction fabric. The degree of magnetic anisotropy is higher along axial surfaces than on limbs. At the anticline hinge, oblate magnetic ellipsoids with an east–west-aligned lineation and a bedding-parallel magnetic foliation demonstrate the overprinting of the LPS magnetic fabric during the emplacement of the underlying thrust sheet. AMS data record fold kinematics characterized by constant-length limb rotation about pinned hinges and are compatible with kinematics recorded by growth strata geometries. This study emphasizes that AMS is a very sensitive measure of depositional, compaction and tectonic fabrics in marine clastic rocks in the diagenetic realm.
DOI: 10.6084/m9.figshare.3453989
title: A carbonate carbon isotope record for the late Givetian (Middle Devonian) Global Taghanic Biocrisis in the type region (northern Appalachian Basin)

description: During the Global Taghanic Biocrisis (<em>c.</em> 385 Ma), Middle Devonian faunas worldwide underwent extinction. In the biocrisis type region, the northern Appalachian Basin, biodiversity changes occurred through three bioevents that ultimately resulted in the loss of numerous endemic taxa. Carbon isotope excursions during this biocrisis have been documented in various stratigraphic successions, but never in the type region. Herein, we reconstruct changes in δ<sup>13</sup>C<sub>carb</sub> from the biocrisis type region and compare these changes to local faunal transitions. An approximately 1.5‰ negative excursion corresponds to the first bioevent, a time of inferred global warming and replacement of most endemic taxa of the mid-palaeolatitude Appalachian Basin by invasive palaeoequatorial taxa. An approximately 2‰ positive excursion is associated with the second bioevent, recognized as a return of the endemic fauna and the loss of invasive taxa. This positive excursion occurs near the <em>Polygnathus ansatus–Ozarkodina semialternans</em> zonal boundary and is recognized elsewhere. Faunal cosmopolitanism associated with the third bioevent corresponds with an inflection in the carbon isotope record from negative to positive trending values, which agrees with a positive carbon record excursion seen elsewhere at the <em>semialternans</em>–<em>Schmidtognathus hermanni</em> zonal boundary. This new carbon isotope record provides an important reference for recognizing this biocrisis in other areas and facies.
DOI: 10.6084/m9.figshare.3453989.v1
title: A carbonate carbon isotope record for the late Givetian (Middle Devonian) Global Taghanic Biocrisis in the type region (northern Appalachian Basin)

description: During the Global Taghanic Biocrisis (<em>c.</em> 385 Ma), Middle Devonian faunas worldwide underwent extinction. In the biocrisis type region, the northern Appalachian Basin, biodiversity changes occurred through three bioevents that ultimately resulted in the loss of numerous endemic taxa. Carbon isotope excursions during this biocrisis have been documented in various stratigraphic successions, but never in the type region. Herein, we reconstruct changes in δ<sup>13</sup>C<sub>carb</sub> from the biocrisis type region and compare these changes to local faunal transitions. An approximately 1.5‰ negative excursion corresponds to the first bioevent, a time of inferred global warming and replacement of most endemic taxa of the mid-palaeolatitude Appalachian Basin by invasive palaeoequatorial taxa. An approximately 2‰ positive excursion is associated with the second bioevent, recognized as a return of the endemic fauna and the loss of invasive taxa. This positive excursion occurs near the <em>Polygnathus ansatus–Ozarkodina semialternans</em> zonal boundary and is recognized elsewhere. Faunal cosmopolitanism associated with the third bioevent corresponds with an inflection in the carbon isotope record from negative to positive trending values, which agrees with a positive carbon record excursion seen elsewhere at the <em>semialternans</em>–<em>Schmidtognathus hermanni</em> zonal boundary. This new carbon isotope record provides an important reference for recognizing this biocrisis in other areas and facies.
DOI: 10.6084/m9.figshare.3453986
title: Palaeogene climate evolution in the Paris Basin from oxygen stable isotope (δ<sup>18</sup>O) compositions of marine molluscs

description: The constraint of temperature evolution in coastal environments is an important factor in deciphering the Earth’s global climatic history. In this study, we reconstruct the evolution of sea-surface palaeotemperatures from the oxygen stable isotope compositions in four marine molluscs families in the Paris Basin during the Palaeogene. The combination of several taxa living in different environments is used to limit uncertainties related to the influence of salinity variations on palaeotemperature estimations. One family of bivalves (oysters) and three families of gastropods (Volutidae, Cerithiidae and Turritellidae) were sampled in the French part of the Paris Basin, in Belgium and in the Isle of Wight (southern England). Maximum seawater temperatures were observed during the Early Eocene (<em>c</em>. 30°C), which correspond to the Early Eocene Climatic Optimum, and temperatures then decreased until the Lutetian (<em>c</em>. 20°C). A transient warming, identified as the Middle Eocene Climatic Optimum, occurred during the Bartonian, when temperatures reached 32°C. Temperatures decreased through the Eocene–Oligocene boundary, the coolest interval of the Palaeogene (<em>c</em>. 12°C). A final warming period occurred throughout the Early Oligocene, with temperatures reaching 24°C. The fossils analysed thus record the global climatic intervals of the Palaeogene.
DOI: 10.6084/m9.figshare.3453986.v1
title: Palaeogene climate evolution in the Paris Basin from oxygen stable isotope (δ<sup>18</sup>O) compositions of marine molluscs

description: The constraint of temperature evolution in coastal environments is an important factor in deciphering the Earth’s global climatic history. In this study, we reconstruct the evolution of sea-surface palaeotemperatures from the oxygen stable isotope compositions in four marine molluscs families in the Paris Basin during the Palaeogene. The combination of several taxa living in different environments is used to limit uncertainties related to the influence of salinity variations on palaeotemperature estimations. One family of bivalves (oysters) and three families of gastropods (Volutidae, Cerithiidae and Turritellidae) were sampled in the French part of the Paris Basin, in Belgium and in the Isle of Wight (southern England). Maximum seawater temperatures were observed during the Early Eocene (<em>c</em>. 30°C), which correspond to the Early Eocene Climatic Optimum, and temperatures then decreased until the Lutetian (<em>c</em>. 20°C). A transient warming, identified as the Middle Eocene Climatic Optimum, occurred during the Bartonian, when temperatures reached 32°C. Temperatures decreased through the Eocene–Oligocene boundary, the coolest interval of the Palaeogene (<em>c</em>. 12°C). A final warming period occurred throughout the Early Oligocene, with temperatures reaching 24°C. The fossils analysed thus record the global climatic intervals of the Palaeogene.
DOI: 10.6084/m9.figshare.3453983
title: <sup>40</sup>Ar/<sup>39</sup>Ar phlogopite geochronology of lamprophyre dykes in Cornwall, UK: new age constraints on Early Permian post-collisional magmatism in the Rhenohercynian Zone, SW England

description: The spatial and temporal association of post-collisional granites and lamprophyre dykes is a common but enigmatic relationship in many orogenic belts, including the Variscan orogenic belt of SW England. The geology of SW England has long been interpreted to reflect orogenic processes associated with the closure of the Rheic Ocean and the formation of Pangaea. The SW England peninsula is composed largely of Early Devonian to Carboniferous volcano-sedimentary successions deposited in synrift and subsequent syncollisional basins that underwent deformation and low-grade regional metamorphism during the Variscan orogeny. Voluminous Early Permian granitic magmatism (Cornubian Batholith) is considered to be broadly coeval with the emplacement of lamprophyric dykes and lamprophyric and basaltic lava flows, largely on the basis of geochronological data from lamprophyric lavas in Devon. Although published geochronological data for Cornish lamprophyre dykes are consistent with this interpretation, these data are limited largely to imprecise K–Ar whole-rock and biotite analyses, hindering the understanding of the processes responsible for their genesis and their relationship to granitic magmatism and regional Variscan tectonics. <sup>40</sup>Ar/<sup>39</sup>Ar geochronological data for four previously undated lamprophyre dykes from Cornwall, combined with published data, suggest that lamprophyre magmatism occurred between <em>c</em>. 293.6 and <em>c</em>. 285.4 Ma, supporting previous inferences that their emplacement was coeval with the Cornubian Batholith. These data provide insights into (1) the relative timing between the lamprophyres and basalts, the Cornubian batholith and post-collisional magmatism elsewhere in the European Variscides, and (2) the post-collisional processes responsible for the generation and emplacement of lamprophyres, basalts and granitoids.
DOI: 10.6084/m9.figshare.3453983.v1
title: <sup>40</sup>Ar/<sup>39</sup>Ar phlogopite geochronology of lamprophyre dykes in Cornwall, UK: new age constraints on Early Permian post-collisional magmatism in the Rhenohercynian Zone, SW England

description: The spatial and temporal association of post-collisional granites and lamprophyre dykes is a common but enigmatic relationship in many orogenic belts, including the Variscan orogenic belt of SW England. The geology of SW England has long been interpreted to reflect orogenic processes associated with the closure of the Rheic Ocean and the formation of Pangaea. The SW England peninsula is composed largely of Early Devonian to Carboniferous volcano-sedimentary successions deposited in synrift and subsequent syncollisional basins that underwent deformation and low-grade regional metamorphism during the Variscan orogeny. Voluminous Early Permian granitic magmatism (Cornubian Batholith) is considered to be broadly coeval with the emplacement of lamprophyric dykes and lamprophyric and basaltic lava flows, largely on the basis of geochronological data from lamprophyric lavas in Devon. Although published geochronological data for Cornish lamprophyre dykes are consistent with this interpretation, these data are limited largely to imprecise K–Ar whole-rock and biotite analyses, hindering the understanding of the processes responsible for their genesis and their relationship to granitic magmatism and regional Variscan tectonics. <sup>40</sup>Ar/<sup>39</sup>Ar geochronological data for four previously undated lamprophyre dykes from Cornwall, combined with published data, suggest that lamprophyre magmatism occurred between <em>c</em>. 293.6 and <em>c</em>. 285.4 Ma, supporting previous inferences that their emplacement was coeval with the Cornubian Batholith. These data provide insights into (1) the relative timing between the lamprophyres and basalts, the Cornubian batholith and post-collisional magmatism elsewhere in the European Variscides, and (2) the post-collisional processes responsible for the generation and emplacement of lamprophyres, basalts and granitoids.
DOI: 10.6084/m9.figshare.3453980
title: Distinguishing diapirs from inflated plutons: an integrated rock magnetic fabric and structural study on the Roundstone Pluton, western Ireland

description: Granitoid plutons account for much of the continental crust and are critical in the generation of several economic resources. Despite over a century of research, the fundamental process by which large felsic bodies intrude remains controversial. Two contrasting models persist: (1) mass ascent and subsequent cooling of magma (diapirism); (2) sheet ascent and subsequent emplacement (laccoliths). The latter hypothesis is different from the former as distinct ascent and emplacement processes must occur and be identifiable; traditional field methods rarely allow this important distinction to be made. We present field, petrographic and anisotropy of magnetic susceptibility data from the Roundstone Pluton, Connemara, western Ireland, which was previously considered a diapiric intrusion. The new data reveal anomalous subvertical magmatic lineations in the core of this circular intrusion as well as a suite of magmatic and submagmatic fabrics that parallel NNW–SSE country rock faults and coeval G2 sheets within the pluton. We deduce that these structures reflect a distinct centralized ascent process along a NNW–SSE conduit. Lateral emplacement and pluton inflation followed, ultimately forming a punched laccolith. We conclude that the combined application of the above techniques provides a unique insight into pluton architecture that removes ambiguity between contrasting diapiric and inflated pluton models.
DOI: 10.6084/m9.figshare.3453980.v1
title: Distinguishing diapirs from inflated plutons: an integrated rock magnetic fabric and structural study on the Roundstone Pluton, western Ireland

description: Granitoid plutons account for much of the continental crust and are critical in the generation of several economic resources. Despite over a century of research, the fundamental process by which large felsic bodies intrude remains controversial. Two contrasting models persist: (1) mass ascent and subsequent cooling of magma (diapirism); (2) sheet ascent and subsequent emplacement (laccoliths). The latter hypothesis is different from the former as distinct ascent and emplacement processes must occur and be identifiable; traditional field methods rarely allow this important distinction to be made. We present field, petrographic and anisotropy of magnetic susceptibility data from the Roundstone Pluton, Connemara, western Ireland, which was previously considered a diapiric intrusion. The new data reveal anomalous subvertical magmatic lineations in the core of this circular intrusion as well as a suite of magmatic and submagmatic fabrics that parallel NNW–SSE country rock faults and coeval G2 sheets within the pluton. We deduce that these structures reflect a distinct centralized ascent process along a NNW–SSE conduit. Lateral emplacement and pluton inflation followed, ultimately forming a punched laccolith. We conclude that the combined application of the above techniques provides a unique insight into pluton architecture that removes ambiguity between contrasting diapiric and inflated pluton models.
DOI: 10.6084/m9.figshare.3453971
title: New constraints on the timing of partial melting and deformation along the Nyalam section (central Himalaya): implications for extrusion models

description: New structural, U–Th/Pb and Ar/Ar data along the Nyalam section constrain the timing of partial melting, crystallization and deformation in the Greater Himalayan Sequence. Prograde metamorphism was followed by the onset of partial melting at <em>c.</em> 30 Ma. In the central Greater Himalayan Sequence, <em>in situ</em> melts crystallized between 24 and 18 Ma. Subsequent cooling was very fast (<em>c.</em> 200 °C Ma<sup>−1</sup>) and coeval with the emplacement of undeformed dykes that lasted until <em>c.</em> 15 Ma. In the upper Greater Himalayan Sequence, fast cooling continued until <em>c.</em> 13 Ma. Combined with published <em>P</em>–<em>T</em> and thermochronological data from the Langtang and Dudh Kosi valleys, these data imply that: (a) the partial melt zone thinned over time; (b) the end of melting preceded the end of motion on the Main Central Thrust and the South Tibetan Detachment by 6 and 2 Ma, respectively; (c) the South Tibetan Detachment possibly initiated at <em>c.</em> 25 Ma, probably reactivating a pre-existing thrust; and (d) the present-day topography has been established for &lt;6 Ma and focused erosion on the present-day southern slopes of the Himalaya was not active at the time of the exhumation of the Greater Himalayan Sequence. These observations suggest that the Main Central Thrust/South Tibetan Detachment systems are not passive structures induced by focused erosion, as has been suggested previously by some lower crustal channel flow models.