cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.28621534
title: Accreted seamounts/oceanic plateaus in the Fuyun accretionary complex in the southern Altaids

description: The Late Palaeozoic tectonic evolution of the Chinese Altai-East Junggar orogenic belt, particularly regarding the subduction of the Ob-Zaisan Ocean, remains a topic of ongoing debate. In this study, we present geochronological, geochemical, and Sr-Nd isotopic data of alkaline basic blocks recently discovered in the Fuyun accretionary complex along the Erqis tectonic belt, which represents a relic of the Ob-Zaisan Ocean in the southwest of Fuyun County. Apatite U-Pb dating of three gabbro and one basalt samples reveals that they were formed in the Early Carboniferous (334 ± 8 Ma, 344 ± 19 Ma, 347 ± 28 Ma, and 350 ± 13 Ma, respectively). The gabbro samples display similar geochemical characteristics, with strong enrichment in light rare-earth elements and depletion in heavy rare-earth elements, which are comparable to typical ocean island basalts (OIB). In addition, the OIB-type basic samples (three gabbros and one basalt) exhibit depleted isotopic compositions with low initial <sup>87</sup>Sr/<sup>86</sup>Sr ratios of 0.7041 to 0.7051 and positive εNd(t) values of + 5.24 to + 7.11. Thus, we suggest that the OIB-type gabbro and basalt blocks within the tectonic mélange were derived from a plume-related mantle source. Integrating these results with previous studies, we propose that these OIB-like basic blocks in the tectonic mélange might represent the relics of mantle plume-derived seamounts/oceanic plateaus. These blocks were likely accreted into the Fuyun accretionary complex due to its convex topography, associated with the southward subduction of the Ob-Zaisan Ocean during the latest Early Carboniferous.
DOI: 10.6084/m9.figshare.28621534.v1
title: Accreted seamounts/oceanic plateaus in the Fuyun accretionary complex in the southern Altaids

description: The Late Palaeozoic tectonic evolution of the Chinese Altai-East Junggar orogenic belt, particularly regarding the subduction of the Ob-Zaisan Ocean, remains a topic of ongoing debate. In this study, we present geochronological, geochemical, and Sr-Nd isotopic data of alkaline basic blocks recently discovered in the Fuyun accretionary complex along the Erqis tectonic belt, which represents a relic of the Ob-Zaisan Ocean in the southwest of Fuyun County. Apatite U-Pb dating of three gabbro and one basalt samples reveals that they were formed in the Early Carboniferous (334 ± 8 Ma, 344 ± 19 Ma, 347 ± 28 Ma, and 350 ± 13 Ma, respectively). The gabbro samples display similar geochemical characteristics, with strong enrichment in light rare-earth elements and depletion in heavy rare-earth elements, which are comparable to typical ocean island basalts (OIB). In addition, the OIB-type basic samples (three gabbros and one basalt) exhibit depleted isotopic compositions with low initial <sup>87</sup>Sr/<sup>86</sup>Sr ratios of 0.7041 to 0.7051 and positive εNd(t) values of + 5.24 to + 7.11. Thus, we suggest that the OIB-type gabbro and basalt blocks within the tectonic mélange were derived from a plume-related mantle source. Integrating these results with previous studies, we propose that these OIB-like basic blocks in the tectonic mélange might represent the relics of mantle plume-derived seamounts/oceanic plateaus. These blocks were likely accreted into the Fuyun accretionary complex due to its convex topography, associated with the southward subduction of the Ob-Zaisan Ocean during the latest Early Carboniferous.
DOI: 10.3535/e08-2e3-2f5
title: Gammarus tigrinus Sexton, 1939

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/jad-hgj-vrd
title: Gammarus salinus Spooner, 1947

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.6084/m9.figshare.28563978
title: India-Asia collisional processes: constraints from the Eocene magmatic rocks in the southern Tibetan Plateau

description: The India-Asia collision has been one of the most significant geological events on Earth over the last 100 Ma. However, the understanding of this collisional process remains highly controversial. In this study, we examined Eocene magmatic rocks in the Qiongguo area, southern Tibet, using geochemistry, zircon U-Pb age, and Lu-Hf isotopic analysis. The results show that the Qiongguo magmatic rocks were formed at 52–48 Ma. The dacites were derived from partial melting of the lower crust, and the rhyolites formed by the mixing of mantle- and crust-derived magmas. The La/Yb, Sm/Yb, and Dy/Yb values are widely used for the quantitative inversion of crustal thickness. We found that the La/Yb, Sm/Yb, and Dy/Yb values of 70–40 Ma intermediate-acidic magmatic rocks in the southern Tibetan Plateau began to increase from ca. 58 Ma, reached a peak at ca. 52 Ma, and then slowly decreased, indicating that crustal thickening-thinning processes may have occurred during the Eocene and crustal thickening peaked at ca. 52 Ma. The values of the zircon U-Pb ages, zircon saturation temperatures, ε<sub>Hf</sub>(t), and ε<sub>Nd</sub>(t) of magmatic rocks in the southern Tibetan Plateau all peaked at ca. 52 Ma, indicating the occurrence of a significant tectono-thermal anomaly and mantle upwelling event, which may have been the result of the slab breakoff of the Neo-Tethyan oceanic lithosphere after the India-Asia collision. Combined with previous data, these data show that the initial India-Asia collision began no later than ca. 58 Ma, and the continental crust gradually thickened and peaked at ca. 52 Ma. Subsequently, owing to the obstruction of the negative buoyancy of the continental crust, the continental crust decoupled from the oceanic crust and slab breakoff occurred, resulting in a wide range of tectono-thermal anomalies and mantle upwelling events and changing the tectonic background of the orogenic belt from extrusion to extension.
DOI: 10.6084/m9.figshare.28572250
title: Alkaline-rich intermediate and felsic melts beneath the NW Iranian plate: new insights from coeval silica-undersaturated and -saturated rocks

description: New whole-rock major and trace element data, coupled with Sr–Nd isotopic ratios data, zircon Hf isotopes, and U–Pb geochronology are presented for three alkaline intrusions (Hashroud, Sisan, and Sarab) in the Zanjan-Takab complex in northwestern Iran, to investigate their sources, petrogenesis, and tectonic implications of emplacement. The Hashroud and Sisan plutons are mainly composed of silica-saturated granite and syenogranite, respectively, whereas the Sarab region consists of nepheline-bearing syenite, and associated undersaturated lavas ranging in composition from tephri-phonolite to trachy-basalt/andesite. Zircon U–Pb geochronology gives emplacement ages of 38 and 36 Ma for the Hashroud and Sisan silica-saturated rocks, which are slightly younger than the Sarab silica-undersaturated rocks (40 Ma). Silica-undersaturated and silica-saturated rocks differ from each other mostly in terms of their silica content, but show comparable incompatible trace element distributions, typical of subduction-related magmatic rocks. The undersaturated rocks display higher LILE/HFSE (Ba/Th: up to 365), but relatively similar LILE/LREE (Ba/La: 13–44) values to those of saturated rocks (Ba/Th: up to 38; Ba/La: up to 27). Silica-undersaturated and -saturated rocks also show distinct Sr–Nd–Pb isotopic compositions, with the former having less radiogenic Sr (<sup>87</sup>Sr/<sup>86</sup>Sr, 0.70452–0.70510) and Pb (<sup>206</sup>Pb/<sup>204</sup>Pb, 18.61–18.67; <sup>207</sup>Pb/<sup>204</sup>Pb, 15.57–15.60; <sup>208</sup>Pb/<sup>204</sup>Pb, 38.64–38.74) and more radiogenic Nd (<sup>143</sup>Nd/<sup>144</sup>Nd, 0.512648–0.512674) than the latter (<sup>87</sup>Sr/<sup>86</sup>Sr, 0.70619–0.71409; <sup>206</sup>Pb/<sup>204</sup>Pb, 18.78–18.82; <sup>207</sup>Pb/<sup>204</sup>Pb, 15.60–15.63; <sup>208</sup>Pb/<sup>204</sup>Pb, 38.78–38.82; <sup>143</sup>Nd/<sup>144</sup>Nd, 0.512613–0.512620). Geochemical and isotopic compositions of the silica-undersaturated rocks suggest the involvement of fluids derived from subducted oceanic crust and subordinate sediment as metasomatizing agents in their mantle source. On the other hand, the studied silica-saturated units, which crystallized from mafic parental melts modified by crustal assimilation and fractional crystallization, originated from a lithospheric mantle source that had been metasomatized via a relatively high volume of terrigenous subducted sediment melts. Both the Eocene saturated and undersaturated igneous rocks formed in a post-collisional extensional setting. Our study, along with compiled data, also finally settles the long-standing debate about the geodynamic evolution of the NW Iranian belt, showing that a compressive to extensional tectonic regime existed during the Arabia–Eurasia collision. This was related to the Neo-Tethyan slab roll-back, which generated alkali-rich magmatic rocks throughout the NW Iranian belt.
DOI: 10.6084/m9.figshare.28572250.v1
title: Alkaline-rich intermediate and felsic melts beneath the NW Iranian plate: new insights from coeval silica-undersaturated and -saturated rocks

description: New whole-rock major and trace element data, coupled with Sr–Nd isotopic ratios data, zircon Hf isotopes, and U–Pb geochronology are presented for three alkaline intrusions (Hashroud, Sisan, and Sarab) in the Zanjan-Takab complex in northwestern Iran, to investigate their sources, petrogenesis, and tectonic implications of emplacement. The Hashroud and Sisan plutons are mainly composed of silica-saturated granite and syenogranite, respectively, whereas the Sarab region consists of nepheline-bearing syenite, and associated undersaturated lavas ranging in composition from tephri-phonolite to trachy-basalt/andesite. Zircon U–Pb geochronology gives emplacement ages of 38 and 36 Ma for the Hashroud and Sisan silica-saturated rocks, which are slightly younger than the Sarab silica-undersaturated rocks (40 Ma). Silica-undersaturated and silica-saturated rocks differ from each other mostly in terms of their silica content, but show comparable incompatible trace element distributions, typical of subduction-related magmatic rocks. The undersaturated rocks display higher LILE/HFSE (Ba/Th: up to 365), but relatively similar LILE/LREE (Ba/La: 13–44) values to those of saturated rocks (Ba/Th: up to 38; Ba/La: up to 27). Silica-undersaturated and -saturated rocks also show distinct Sr–Nd–Pb isotopic compositions, with the former having less radiogenic Sr (<sup>87</sup>Sr/<sup>86</sup>Sr, 0.70452–0.70510) and Pb (<sup>206</sup>Pb/<sup>204</sup>Pb, 18.61–18.67; <sup>207</sup>Pb/<sup>204</sup>Pb, 15.57–15.60; <sup>208</sup>Pb/<sup>204</sup>Pb, 38.64–38.74) and more radiogenic Nd (<sup>143</sup>Nd/<sup>144</sup>Nd, 0.512648–0.512674) than the latter (<sup>87</sup>Sr/<sup>86</sup>Sr, 0.70619–0.71409; <sup>206</sup>Pb/<sup>204</sup>Pb, 18.78–18.82; <sup>207</sup>Pb/<sup>204</sup>Pb, 15.60–15.63; <sup>208</sup>Pb/<sup>204</sup>Pb, 38.78–38.82; <sup>143</sup>Nd/<sup>144</sup>Nd, 0.512613–0.512620). Geochemical and isotopic compositions of the silica-undersaturated rocks suggest the involvement of fluids derived from subducted oceanic crust and subordinate sediment as metasomatizing agents in their mantle source. On the other hand, the studied silica-saturated units, which crystallized from mafic parental melts modified by crustal assimilation and fractional crystallization, originated from a lithospheric mantle source that had been metasomatized via a relatively high volume of terrigenous subducted sediment melts. Both the Eocene saturated and undersaturated igneous rocks formed in a post-collisional extensional setting. Our study, along with compiled data, also finally settles the long-standing debate about the geodynamic evolution of the NW Iranian belt, showing that a compressive to extensional tectonic regime existed during the Arabia–Eurasia collision. This was related to the Neo-Tethyan slab roll-back, which generated alkali-rich magmatic rocks throughout the NW Iranian belt.
DOI: 10.3535/864-mtg-qr0
title: Gammarus pulex gallicus (S. Karaman, 1931)

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.6084/m9.figshare.28510723
title: Deciphering the origin of early continental crust: insights from newly identified ~3.8 Ga granitoids in the Anshan area, North China Craton

description: Numerous questions regarding the formation and evolution of Earth’s early continental crust remain unresolved. Ancient rocks are essential to understanding these early geological processes. This study provides new geochronology, geochemistry, and zircon Hf-O isotope data from recently discovered Eoarchean granitoids in the Anshan area of the North China Craton (NCC). Zircon U-Pb dating indicates that these granitoids formed at <i>ca</i>. 3.8 Ga and include both trondhjemitic and monzogranitic gneisses. The trondhjemitic gneisses are characterized by high SiO<sub>2</sub> and Na<sub>2</sub>O contents, low magnesium number (Mg#), low Sr/Y and (La/Yb)<sub>N</sub> ratios, and slightly negative Eu anomalies. These rocks exhibit enrichment in light rare earth elements (LREE) with flat heavy rare earth element (HREE) patterns. Their zircon ε<sub>Hf</sub>(<i>t</i>) values range from −3.34 to + 1.09, with two-stage model ages (T<sub>DM</sub><sup>2</sup>) between 4.43 and 3.99 Ga. The magmatic zircons show δ<sup>18</sup>O values of + 5.33‰ – +6.98‰. These geochemical and Hf-O isotope features suggest that the trondhjemitic gneisses, classified as low-pressure type, likely formed through the partial melting of Hadean to early Eoarchean mafic proto-crust under upper-amphibolite facies conditions. In comparison, the monzogranitic gneisses display higher SiO<sub>2</sub> and K<sub>2</sub>O levels, lower Sr/Y, (La/Yb)<sub>N</sub>, and (Gd/Yb)<sub>N</sub> ratios, and more pronounced negative Eu anomalies. These monzogranitic gneisses are enriched in Rb, Th, and U and depleted in Ba, Sr, Nb, P and Ti. Such geochemical traits classify them as highly differentiated granites. Zircon Hf isotope data reveal radiogenic values, with T<sub>DM</sub><sup>2</sup> ages between 4.23 and 4.01 Ga and ε<sub>Hf</sub>(<i>t</i>) values ranging from −1.60 to + 0.85. These evidences suggest that the monzogranitic gneisses were derived from the partial melting of ancient felsic source and underwent fractional crystallization during the late stages of magma evolution. The diversity of the <i>ca</i>. 3.8 Ga granitoids indicates the presence of a highly evolved continental crust in the NCC during the early Eoarchean. Hf isotope data show that the earliest crust grew primarily through the partial melting of juvenile crust derived from a depleted mantle, accompanied by certain reworking or recycling of pre-existing continental material. The <i>ca</i>. 3.8 Ga trondhjemitic and monzogranitic gneisses likely formed in an extension environment, such as intraplate rifting setting. Continental crust evolution in the NCC during early Eoarchean was primarily driven by magma underplating associated with asthenospheric mantle upwelling, potentially linked to mantle plume activity.
DOI: 10.6084/m9.figshare.28510723.v1
title: Deciphering the origin of early continental crust: insights from newly identified ~3.8 Ga granitoids in the Anshan area, North China Craton

description: Numerous questions regarding the formation and evolution of Earth’s early continental crust remain unresolved. Ancient rocks are essential to understanding these early geological processes. This study provides new geochronology, geochemistry, and zircon Hf-O isotope data from recently discovered Eoarchean granitoids in the Anshan area of the North China Craton (NCC). Zircon U-Pb dating indicates that these granitoids formed at <i>ca</i>. 3.8 Ga and include both trondhjemitic and monzogranitic gneisses. The trondhjemitic gneisses are characterized by high SiO<sub>2</sub> and Na<sub>2</sub>O contents, low magnesium number (Mg#), low Sr/Y and (La/Yb)<sub>N</sub> ratios, and slightly negative Eu anomalies. These rocks exhibit enrichment in light rare earth elements (LREE) with flat heavy rare earth element (HREE) patterns. Their zircon ε<sub>Hf</sub>(<i>t</i>) values range from −3.34 to + 1.09, with two-stage model ages (T<sub>DM</sub><sup>2</sup>) between 4.43 and 3.99 Ga. The magmatic zircons show δ<sup>18</sup>O values of + 5.33‰ – +6.98‰. These geochemical and Hf-O isotope features suggest that the trondhjemitic gneisses, classified as low-pressure type, likely formed through the partial melting of Hadean to early Eoarchean mafic proto-crust under upper-amphibolite facies conditions. In comparison, the monzogranitic gneisses display higher SiO<sub>2</sub> and K<sub>2</sub>O levels, lower Sr/Y, (La/Yb)<sub>N</sub>, and (Gd/Yb)<sub>N</sub> ratios, and more pronounced negative Eu anomalies. These monzogranitic gneisses are enriched in Rb, Th, and U and depleted in Ba, Sr, Nb, P and Ti. Such geochemical traits classify them as highly differentiated granites. Zircon Hf isotope data reveal radiogenic values, with T<sub>DM</sub><sup>2</sup> ages between 4.23 and 4.01 Ga and ε<sub>Hf</sub>(<i>t</i>) values ranging from −1.60 to + 0.85. These evidences suggest that the monzogranitic gneisses were derived from the partial melting of ancient felsic source and underwent fractional crystallization during the late stages of magma evolution. The diversity of the <i>ca</i>. 3.8 Ga granitoids indicates the presence of a highly evolved continental crust in the NCC during the early Eoarchean. Hf isotope data show that the earliest crust grew primarily through the partial melting of juvenile crust derived from a depleted mantle, accompanied by certain reworking or recycling of pre-existing continental material. The <i>ca</i>. 3.8 Ga trondhjemitic and monzogranitic gneisses likely formed in an extension environment, such as intraplate rifting setting. Continental crust evolution in the NCC during early Eoarchean was primarily driven by magma underplating associated with asthenospheric mantle upwelling, potentially linked to mantle plume activity.
DOI: 10.6084/m9.figshare.28563978.v1
title: India-Asia collisional processes: constraints from the Eocene magmatic rocks in the southern Tibetan Plateau

description: The India-Asia collision has been one of the most significant geological events on Earth over the last 100 Ma. However, the understanding of this collisional process remains highly controversial. In this study, we examined Eocene magmatic rocks in the Qiongguo area, southern Tibet, using geochemistry, zircon U-Pb age, and Lu-Hf isotopic analysis. The results show that the Qiongguo magmatic rocks were formed at 52–48 Ma. The dacites were derived from partial melting of the lower crust, and the rhyolites formed by the mixing of mantle- and crust-derived magmas. The La/Yb, Sm/Yb, and Dy/Yb values are widely used for the quantitative inversion of crustal thickness. We found that the La/Yb, Sm/Yb, and Dy/Yb values of 70–40 Ma intermediate-acidic magmatic rocks in the southern Tibetan Plateau began to increase from ca. 58 Ma, reached a peak at ca. 52 Ma, and then slowly decreased, indicating that crustal thickening-thinning processes may have occurred during the Eocene and crustal thickening peaked at ca. 52 Ma. The values of the zircon U-Pb ages, zircon saturation temperatures, ε<sub>Hf</sub>(t), and ε<sub>Nd</sub>(t) of magmatic rocks in the southern Tibetan Plateau all peaked at ca. 52 Ma, indicating the occurrence of a significant tectono-thermal anomaly and mantle upwelling event, which may have been the result of the slab breakoff of the Neo-Tethyan oceanic lithosphere after the India-Asia collision. Combined with previous data, these data show that the initial India-Asia collision began no later than ca. 58 Ma, and the continental crust gradually thickened and peaked at ca. 52 Ma. Subsequently, owing to the obstruction of the negative buoyancy of the continental crust, the continental crust decoupled from the oceanic crust and slab breakoff occurred, resulting in a wide range of tectono-thermal anomalies and mantle upwelling events and changing the tectonic background of the orogenic belt from extrusion to extension.
DOI: 10.3535/ldn-2jk-v64
title: Gammarus pulex (Linnaeus, 1758)

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/qhj-dkt-f5p
title: Gammarus pulex (Linnaeus, 1758)

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/h7p-cad-z33
title: Gammarus fossarum Koch, 1836

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/wgq-9bb-w9k
title: Niphargus schellenbergi S. Karaman, 1932

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/j99-jxg-hnw
title: Gammarus balcanicus Schäferna, 1923

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/qzr-ax8-bbj
title: Pectenogammarus stammeri (S. Karaman, 1931)

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/y7k-c1a-8xz
title: Grandidierella Coutière, 1904

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/260-g6g-ks4
title: Parascelus edwardsi Claus, 1879

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/71f-lv3-x0b
title: Parhomoeogammarus pacaudi (Hubault & Ruffo, 1956)

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/arv-5rk-bpa
title: Gammarella fucicola (Leach, 1814)

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/5kn-rs9-gae
title: Parascelus edwardsi Claus, 1879

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/xsf-k4q-735
title: Marinogammarus marinus (Leach, 1816)

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/kkc-jsn-ktn
title: Niphargus schellenbergi S. Karaman, 1932

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/tbx-tlf-0qh
title: Elasmopus pocillimanus (Spence Bate, 1863)

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/hfy-v61-m67
title: Gammarus fossarum Koch, 1836

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/tzn-78v-hhv
title: Quadrimaera inaequipes (A. Costa in Hope, 1851)

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/r3p-mr1-n7f
title: Gammarus zaddachi Sexton, 1912

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/1ls-75p-6gw
title: Gammarus tigrinus Sexton, 1939

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/ta6-v17-kst
title: Echinogammarus berilloni (Catta, 1878)

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/kb7-y8x-lds
title: Pectenogammarus tibaldii (Pinkster & Stock, 1970)

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/64w-ggw-0f6
title: Gammarus zaddachi Sexton, 1912

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/a6r-y2q-56e
title: Bathyporeia guilliamsoniana (Spence Bate, 1857)

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.
DOI: 10.3535/8v0-28s-yxl
title: Gammarus zaddachi Sexton, 1912

description: Digital Specimen for the physical specimen hosted at Naturalis Biodiversity Center.