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Abstract A total of 146 glass samples from Daoye, Daoye South, and Wujiancuo in southwestern Taiwan were subjected to elemental analysis using LA-ICP-MS and SEM–EDS. These samples cover a time span from the first to the eighth century CE. The results provide evidence of the existence of multiple long-distance glass exchange networks that directly or indirectly connected Taiwan to Southeast Asia, South Asia, West Asia, and possibly the Mediterranean region. The predominance of the South Asian m-Na-Al glass sub-type 1 suggests that Taiwan mainly participated in the South China Sea maritime glass exchange network, while the identification of a newly recognised sub-type, m-Na-Al low Al low Ca, indicates the possibility of small-scale glass production workshops or a less controlled recipe for m-Na-Al glass production. Furthermore, this research reveals compelling evidence linking early v-Na-Ca glass found in Taiwan to origins in Mesopotamia or Sasanian territories, with the secondary production areas remain unclear. In addition, a potash glass and a Roman HIMT glass were also discovered. The chemical profiles of the potash glass do not align with those of early potash glass, while the HIMT glass can be attributed to the Roman Mediterranean. Taken together, these findings shed light on the intricate maritime exchange networks that operated over vast distances, spanning from the eastern part of the South China Sea to West Asia, covering over eight thousand kilometers. This study thus addresses a significant research gap regarding the maritime exchange of glass during the understudied period of the early to mid-1st millennium CE around the South China Sea and beyond.

The Mae Ping shear zone (MPSZ), a major shear zone trending NW-SE in Thailand, is responsible for the left-lateral displacement of the N-S Triassic-Jurassic granitoid and gneiss belt. This displacement is postulated to have contributed to Cenozoic extrusion tectonics. Within the Lan Sang National Park, the MPSZ exposes several intensely deformed lithologies, collectively known as the Lan Sang gneisses. These gneisses have attracted considerable attention for their potential to substantiate the extrusion model. However, the timing of the emplacement of the orthogneiss protolith is still debated. Moreover, the origin and distribution of the Eocene syn-shearing granodiorite within this shear zone are not well understood. To shed light on the magmatic history of the MPSZ, this study utilized zircon U-Pb geochronology to systematically investigate the Lan Sang gneisses. Our findings demonstrate that these gneisses can be categorized into paragneiss and orthogneiss groups. Paragneiss samples feature zircons displaying rounded detrital cores ranging from 3,078 to 450 Ma, with metamorphic rim overgrowth of ca. 200 Ma (most Th/U

Development and maintenance of coral reef ecosystems rely on daily micro-biological activities of healthy corals. Although a comprehensive understanding of coral biological properties, as well as factors negatively affecting coral growth, are essential to conserve existing corals, the current lack of a tractable culture and experimental platform has delayed acquisition of such knowledge. Here we show a highly versatile culture system, “coral-on-a-laboratory dish” (CLD), allowing long-term culturing of various corals in plastic/glass Petri dishes with maintenance of their biological properties. Under optimized conditions, coral microcolonies (~5 mm x 5 mm fragments) of Pocillopora damicornis were cultured for several months in dishes with high survivorship and characteristic growth. These microcolonies maintained their biological properties, such as reproduction, skeleton formation, coral-algal symbiosis, ingestion, and digestion. Thus far, CLD has been used to maintain at least 4 other coral species from 4 other families, including the Acroporidae, the Pocilloporidae, the Poritidae, and the Merulinidae for more than 2 months with 100% survivorship. CLD is applicable to a variety of biophysiological studies, including coral-algal symbiosis and impact assessment of marine pollutants, e.g., a sunscreen substance, oxybenzone, and an organic biocide, Irgarol 1051, at cellular-level resolution. The CLD platform, which allows easy and inexpensive coral maintenance in a laboratory incubator, represents a technological breakthrough that will greatly advance coral studies.

Abstract The evolution of the Taiwan orogen, an active arc–continent collision zone between the North Luzon Arc (NLA) and the Eurasian continent, is recorded in arc volcanic and sedimentary rocks from the Taiyuan retro‐foredeep basin of the Coastal Range, eastern Taiwan. Arc volcanism in the northern NLA experienced a magmatic culmination at 9–7 Ma and a cessation at 5.3–4.3 Ma, based on new U‐Pb zircon ages. Young zircon U‐Pb ages (1.74, 1.58, and

Abstract The crust of Venus is composed of the low lying volcanic planitiae and the elevated, deformed tesserae. It is thought that the tesserae may be composed of silicic igneous rocks and that it may resemble proto-continental crust. The initial development of terrestrial continental crust is likely due to melting and deformation of primitive mafic crust via mantle-plume upwelling and collisional plate processes. Unlike Earth, the lithosphere of Venus is not divided into plates and therefore evolved continental crust, if present, developed primarily by melting of pre-existing mafic crust. Here, we report the results of high pressure equilibrium partial melting experiments using a parental composition similar to the basalt measured at the Venera 14 landing site in order to determine if silicic melts can be generated. It was found that at pressures of 1.5 GPa and 2.0 GPa and temperatures of 1080 °C, 1090 °C, and 1285 °C that tonalitic and granodioritic melts can be generated. The experimental results indicate that silicic rocks may be able to form in the crust of Venus providing the thermal regime is suitable and that the lower crust is basaltic. The implication is that the older, thicker regions of Venusian crust may be partially composed of silicic igneous rocks.

The Singhbhum craton, eastern India records multiple stages of emplacement of Precambrian dyke swarms with contrasting petrogenetic models proposed for their formation. In this study, we document elemental and Sr-Nd isotopic data for three major dyke swarms in the southern part of the craton, including the ca. 2.7 Ga Ghatgaon dyke swarm, the Early Proterozoic Keonjhar dyke swarm and the ca. 1.76 Ga Pipilia dyke swarm. Dyke compositions are dominated by basalt and basaltic andesite with minor andesite, showing trace element signatures typical of continental crustal rocks. Age-corrected Nd isotopic data for Ghatgaon (εNdt = −4.8 to + 4.6), Keonjhar (εNdt = −11.9 to + 3.8), and Pipilia (a single sample with εNdt = −8.8) dyke swarms display substantial variations. The lack of magma compositions that could indicate the presence of elevated mantle potential temperature among the rocks suggests melting regime was likely similar to the ambient mantle. The Dy/Yb and Dy/Dy* systematics of the rocks indicates melting occurred between spinel-stable depths and the spinel-garnet transition zone. The dominantly mafic compositions of the rocks and ubiquitous continental crustal trace element signature are best explained by peridotite source with recycled crustal components, probably in the form of pyroxenites. Our new Nd isotopic data, which argue against any simple secular evolution trend invoked in previous studies, indicate that crustal recycling was likely an episodic phenomenon rather than a discrete, single-stage process since the Archean. Geochemical modelling indicates that a sublithospheric mantle source with (10% or less) recycled crustal components satisfactorily explains the trace element variations of the dyke swarms.

The white ignimbrite layer on top of volcanic sequences in the Coastal Range is the youngest eruption of the northern Luzon Arc in the Taiwan region. A gabbroic enclave was coexisting with the andesitic ignimbrite in this sequence. This study reports the dating results, textural and petrographic descriptions, and geochemical characteristics of the gabbroic enclave and andesitic breccias in the ignimbrite. Both components erupted approximately at 4 Ma, and show enrichment in large ion lithophile elements and depletion in high field strength elements, which are important island arc characteristics. Major and trace elements indicated that the andesitic magma shows larger fractionation and lower degrees of partial melting than the basaltic magma which formed the gabbroic enclaves. We suggest that three sub-stages of magmatism occur during the youngest eruption of the northern Luzon Arc at ~4 Ma. In the first sub-stage, the basaltic magma generated by higher degrees of partial melting from the source rose to a shallow reservoir and cooled to build up the gabbroic wall rocks. Later, lower degrees of partial melting magma were injected into the shallow reservoir and fractionated to intermediate magma causing the second substage. The third sub-stage was activated by the recharged magma, which triggered the intermediate magma to rise along the earlier pathway and assimilated within the gabbroic wall rock. This magma eventually erupted to form the andesitic ignimbrite with gabbroic enclaves within.

The modern coast of China is characterized by complicated hydrology, which might be a potential factor shaping genetic structure of marine organisms. Tridentiger barbatus is a widespread benthic goby in coastal China whose range expansion might depend on larval dispersal in its spawning season. We explored the genetic structure of T. barbatus and its interrelationships with coastal currents, planktonic larval duration, and Pleistocene climate fluctuations. Genealogies of Cytb, Rh, and RAG1 reveal two lineages in T. barbatus, namely the southern and northern lineages. The southern lineage is distributed through the South China Sea to the South Yellow Sea but is absent from the North Yellow Sea and Bohai Sea. The HYCOM average flow field indicates an eddy between the North and South Yellow Seas, which might cause larval retention and limit dispersal of the southern lineage into the North Yellow Sea and the Bohai Sea. The northern lineage is distributed through the South Yellow Sea to the Bohai Sea but is absent from the South China Sea and East China Sea. The distribution of the northern lineage fits the eastward deflection of the Yellow Sea Coastal Current at the boundary of the East China Sea and South Yellow Sea, which might limit southward larval dispersal of the northern lineage into the East China Sea. We also uncovered two Cytb haplotype groups within the southern lineage, namely groups A and B, whose distributions might be shaped by the northward Taiwan Strait Current. The coincidence between the genetic structure of T. barbatus and the coastal currents and eddies strongly implies significant roles of larval dispersal and current transportation in shaping the genetic structure of T. barbatus. In addition, significant isolation by distance is found in the southern lineage, which coincides with its short planktonic larval duration (20–30 days). The inference on divergence time suggests that the observed lineages and haplotype groups in T. barbatus originated in the Pleistocene glaciations. Therefore, the coastal currents, planktonic larval duration, and historical glacial isolation are proposed as important factors shaping the genetic structure of T. barbatus.

The Baima igneous complex (BIC) consists of a cumulate layered gabbroic unit, an Fe-Ti oxide ore zone, and an isotropic quartz syenite. The formation of the BIC is attributed to a variety of petrological processes including: silicate immiscibility, fractional crystallization, and fluxing of fO2 by either internal or external factors. This study attempts to determine if a parental magma similar to high-Ti Emeishan basalt can produce the syenitic rocks of the BIC. The experimental results at atmospheric pressure show that the liquidus temperature and solidus temperature of the basaltic melt are estimated to be 1303 and 1120°C. The crystallization sequence is: titanomagnetite, clinopyroxene (Wo43-47En32-45Fs11-23), and plagioclase (An65-31). The residual liquid composition, represented by quenched glass, evolves from lower SiO2 (~45 wt%) values to higher values (~60 wt%) with corresponding decreases in Ti, Fe, Mg, Ca and increases of Na and K. The results show that a starting composition of high-Ti basalt from the Emeishan large igneous province can produce evolved silicic liquids that resemble the compositions of microgranular enclaves from the Baima syenitic unit.

ABSTRACT Methane-oxidizing bacteria (methanotrophs) play an ecological role in methane and nitrogen fluxes because they are capable of nitrogen fixation and methane oxidation, as indicated by genomic and cultivation-dependent studies. However, the chemical relationships between methanotrophy and diazotrophy and aerobic and anaerobic reactions, respectively, in methanotrophs remain unclear. No study has demonstrated the cooccurrence of both bioactivities in a single methanotroph bacterium in its natural environment. Here, we demonstrate that both bioactivities in type II methanotrophs occur at the single-cell level in the root tissues of paddy rice (Oryza sativa L. cv. Nipponbare). We first verified that difluoromethane, an inhibitor of methane monooxygenase, affected methane oxidation in rice roots. The results indicated that methane assimilation in the roots mostly occurred due to oxygen-dependent processes. Moreover, the results indicated that methane oxidation-dependent and methane oxidation-independent nitrogen fixation concurrently occurred in bulk root tissues. Subsequently, we performed fluorescence in situ hybridization and NanoSIMS analyses, which revealed that single cells of type II methanotrophs (involving six amplicon sequence variants) in paddy rice roots simultaneously and logarithmically fixed stable isotope gases 15N2 and 13CH4 during incubation periods of 0, 23, and 42 h, providing in vivo functional evidence of nitrogen fixation in methanotrophic cells. Furthermore, 15N enrichment in type II methanotrophs at 42 h varied among cells with an increase in 13C accumulation, suggesting that either the release of fixed nitrogen into root systems or methanotroph metabolic specialization is dependent on different microenvironmental niches in the root. IMPORTANCE Atmospheric methane concentrations have been continually increasing, causing methane to become a considerable environmental concern. Methanotrophy may be the key to regulating methane fluxes. Although research suggests that type II methanotrophs are involved in methane oxidation aerobically and nitrogen fixation anaerobically, direct evidence of simultaneous aerobic and anaerobic bioreactions of methanotrophs in situ is still lacking. In this study, a single-cell isotope analysis was performed to demonstrate these in vivo parallel functions of type II methanotrophs in the root tissues of paddy rice (Oryza sativa L. cv. Nipponbare). The results of this study indicated that methanotrophs might provide fixed nitrogen to root systems or depend on cells present in the spatially localized niche of the root tissue. Furthermore, our results suggested that single type II methanotrophic cells performed simultaneous methane oxidation and nitrogen fixation in vivo. Under natural conditions, however, nitrogen accumulation varied at the single-cell level.

Abstract The feeding behavior of the giant ambush-predator “Bobbit worm” (Eunice aphroditois) is spectacular. They hide in their burrows until they explode upwards grabbing unsuspecting prey with a snap of their powerful jaws. The still living prey are then pulled into the sediment for consumption. Although predatory polychaetes have existed since the early Paleozoic, their bodies comprise mainly soft tissue, resulting in a very incomplete fossil record, and virtually nothing is known about their burrows and behavior beneath the seafloor. Here we use morphological, sedimentological, and geochemical data from Miocene strata in northeast Taiwan to erect a new ichnogenus, Pennichnus. This trace fossil consists of an up to 2 m long, 2–3 cm in diameter, L-shaped burrow with distinct feather-like structures around the upper shaft. A comparison of Pennichnus to biological analogs strongly suggests that this new ichnogenus is associated with ambush-predatory worms that lived about 20 million years ago.

AbstractThe Ortosuu and Uchkuduk regions of the Tianshan orogen contain a volumetrically small series of basaltic rocks erupted primarily during the late Mesozoic-Paleogene. Petrology, chemical composition, and P-T geotherm data from xenoliths within the basalts characterize the nature of the lithospheric mantle beneath this orogenic belt. Two groups of clinopyroxene can be identified from the studied xenoliths based on their Mg# and trace element patterns. Group 1, primitive clinopyroxenes, has lower Mg# (86–90) and LREE-depleted patterns than group 2, depleted clinopyroxenes, which are characterized by a relatively high Mg#, 91–92, and LREE-enriched patterns. The REE distribution in group 1 clinopyroxenes suggests that they were controlled by partial melting, whereas group 2 clinopyroxenes are far more complex involving partial melting degrees of 6–11%, and later metasomatism by carbonatite and/or silicate melts. Coupled P-T estimations from geothermobarometry indicate that the more fertile group 1 xenoliths were probably derived from the uppermost mantle, and the more depleted group 2 xenoliths were likely derived from a depth close to the crust mantle boundary.

Rhinogobius formosanus Oshima, 1919 has long been considered an amphidromous goby. However, a landlocked population recently found in the Jingualiao Creek upstream of the Feitsui Reservoir in Taipei suggests that R. formosanus may complete its life in the river. This study aims to verify the habitat use of the landlocked population of R. formosanus collected from the Feitsui Reservoir and an amphidromous population collected in Malian Creek using otolith Sr:Ca ratio analysis. The hypothesis that early life history varies between the landlocked and migratory gobies was also tested. Genetic analyses show that the Feitsui Reservoir and Malian Creek populations are not genetically different. Rhinogobius formosanus from Malian Creek showed high-to-low otolith Sr:Ca ratios suggesting that these specimens spent a planktonic larval stage in the sea followed by a freshwater life at later stages. In contrast, R. formosanus from the Feitsui Reservoir showed constant lower otolith Sr:Ca ratios, implying a landlocked life history of fish in the creek upstream of the reservoir. In addition, the analysis of growth increments showed a longer pelagic larval duration for the fish in the Malian Creek (58.8 days) than those in the Feitsui Reservoir (38.8). Variation of pelagic larval duration in two genetically homogenous populations implies acclimatization to the reservoir by the landlocked gobies. This study shows that R. formosanus, like some other congeners, is capable of adapting to a freshwater landlocked environment in its early developmental stage and supports the hypothesis that landlocked populations may have a shorter pelagic larval duration.

Mineral soda alumina (m-Na-Al) glass is a common glass production group found around the Indo-Pacific region. In Iron Age Taiwan, its presence dates back to the early 1st millennium AD. This research discusses m-Na-Al glass beads excavated from Iron Age sites in Taiwan. No production sites for m-Na-Al have been found, but microstructural analysis suggests m-Na-Al glass appears to originate around South Asia and is exchanged widely. SEM-EDS and EPMA were used to analyse red, orange, yellow, green and blue m-Na-Al glass. The microstructure of the glass shows the presence of plagioclase and alkali feldspar relics in the glass, suggesting a low manufacturing temperature. Copper-based colourants are identified in red, orange, blue and green glass, while lead tin oxide is used in yellow and green glass. It appears that various types of copper-containing raw materials were procured by craftspeople, and a self-reduction process for producing red and orange glass is tentatively proposed. Additionally, the microstructure of yellow glass reveals different colouring paths were used. These results increase our understanding of the selection of raw materials, and provide an impetus for further research on the cross craft interaction between glass and copper production.

Dental modifications, especially dental inlays, were one of the most characteristic biocultural traditions in Ancient Mesoamerica. The main objective of this brief report is to identify the raw material used to elaborate dental inlays in the archaeological site of Reynosa, located in the Southern Pacific Coast of Guatemala. The recent discovery of a massive burial, dated roughly in the Middle-Late Preclassic Period (500 BC–200 BC), put the site in the spotlight. There were found some of the earliest carriers of dental incrustations in Mesoamerica, which represent part of the beginning of the inlay tradition. The analytical method used to determine the raw material was scanning electron microscopy (SEM) with X-ray spectroscopy. The identified raw materials were pyrite and hematite. These findings have opened new concerns about the obtaining and the usage of those materials in this millennial tradition.

The Guéra Massif, in South-Central Chad hosts granitic rocks that were emplaced during distinct intervals (595–590; ∼570; ∼560 Ma) of the Late Ediacaran Central African Orogenic Belt. To the northwest of the Guéra Massif, younger post-collisional granites (554–545 Ma) are found near Lake Fitri. The older (≥590 Ma) rocks have geochemical characteristics of collisional granites whereas the younger (≤570 Ma) rocks are similar to post-collisional granites. Biotite and amphibole were analyzed to constrain the magmatic conditions of the granites. The biotite from the collisional granites tends to have higher Al and Ti and lower Fe# (Fe#average ≈ 0.67) than the post-collisional granites (Fe#average ≈ 0.88). The average crystallization temperatures range from 696 ± 37 to 612 ± 8°C, with the average pressure of crystallization from 0.25 ± 0.09 to 0.13 ± 0.02 GPa, and redox conditions between the nickel-nickel oxide (NNO) and quartz-fayalite-magnetite (QFM) buffers. The biotite crystallization temperatures of the post-collisional rocks are generally lower than the collisional rocks (570 Ma = 630 ± 26 to 619 ± 30°C, 560 Ma = 626 ± 20 to 607 ± 4°C, 550 Ma = 639 ± 18 to 612 ± 13°C), but the crystallization pressures are similar (0.27 ± 0.05 to 0.14 ± 0.04 GPa). The redox conditions transition from the QFM buffer to the wüstite-magnetite (WM) buffer. In contrast, the biotite from the Lake Fitri post-collisional granites crystallized at higher pressure (0.39 ± 0.08 to 0.35 ± 0.03 GPa) but similar redox conditions. The amphiboles in the younger (∼590 Ma) collisional granites and the post-collisional granites yielded crystallization pressure estimates that are generally higher (∼0.6 to 0.1 GPa) than the biotite estimates but there is overlap. The difference in pressure may be due to the timing of crystallization and/or crystal redistribution. Overall, there appears to be a secular change from high to low temperature and pressure whereas the redox conditions appear to be spatially related. The biotite crystallization pressure of the Lake Fitri granites suggests they were likely emplaced into a different domain/terrane of the Saharan Metacraton than the Guéra Massif.

The Yanshanian Orogeny consists of Jurassic to Cretaceous compressional-extensional cycles related to the subduction of the Paleo-Pacific Ocean beneath East Asia. Numerous granitic plutons were emplaced across southeast China at distinct intervals over a period of ∼100 million years that migrate from the interior to the coast. A key region to help constrain the secular evolution of granitic magmatism related to the Yanshanian Orogeny is the Peal River estuary as three distinct Mesozoic magmatic belts congregate. The islands of Taipa and Coloane, Macau Special Administrative Region, are located along the western bank of the Pearl River estuary and are composed of spessartine-bearing biotite leucogranite. In situ zircon geochronology yielded Late Jurassic weighted-mean 206Pb/238U ages of 160.0 ± 2.0 and 161.5 ± 2.0 Ma that correlate to the late Early Yanshanian Orogeny. Inherited zircons of Middle Triassic to Middle Jurassic age were also identified. The rocks are peraluminous, ferroan, calc-alkalic to calcic and classify as post-collisional granite. Geochemical modeling indicates that the chemical variability of the rocks is related to hydrous fractional crystallization under reducing conditions (ΔFMQ −1) at ∼7 km depth. The Sr-Nd isotopes [ISr = 0.71156 to 0.72477; εNd(t) = −7.9 to –8.6], zircon Hf isotopes [εHf(t) = −3.8 to −8.8], incompatible trace element ratios, and whole rock composition indicate that the parental magma was derived primarily from a sedimentary source. It is likely that the islands of Taipa and Coloane form a coherent plutonic complex that may be a member of larger batholith that extends across the Pearl River estuary to Hong Kong. The emplacement of the leucogranites is attributed to decompressional melting associated with a period of crustal relaxation or tensional plate stress that occurred during the transition from low angle subduction to high angle subduction of the Paleo-Pacific plate.

The garnet-amphibolites in Aliabad-Damagh area, occurs as layers and are enveloped by staurolite-schist. They composed predominantly of garnet, hornblende, feldspar (± muscovite and quartz) with titanite, epidote, ilmenite and graphite as accessory minerals. The euhedral garnet porphyroblasts mainly composed of almandine and grossular components, with normal compositional zoning. The hornblende crystals as prophyroblast or in the matrix, are magnesio- and ferro-hornblende (amphibole core) to tchermakitic-hornbelende (amphibole rim) in composition. Muscovites, if present, with minor phengite and paragonite components, are foliated forming minerals. Feldspars vary from pure K-feldspar to sanidine composition in the vicinity of hornblendes and oligoclase in matrix. Epidotes as pure clinozoisite to epidote, form small crystals inside hornblende or in the matrix. Using different thermobarometry methods, T and P estimated as 600-620 (± 25) °C and 5-6 (± 1) kbar, respectively. Calculated P-T-t path, considering core and rim composition of hornblendes, is in accordance with low-pressure (at the beginning of metamorphism) to medium-pressure type (at the end). Considering P-T-t path, metamorphism could occur during Neo-Tethys subduction and collision process in the Mesozoic time

We have developed porTable 950 keV/3.95 MeV X-band (9.3 GHz) electron linear accelerator (LINAC)-based X-ray sources and conducted onsite prestressed concrete (PC) bridge inspection in the last 10 years. A T-shaped PC girder bridge with a thickness of 200–400 mm and a box-shaped PC girder bridge with a thickness of 200–800 mm were tested. X-ray transmission images of flaws such as thinning, fray, and disconnection caused by corrosion of PC wires and unfilled grout were observed. A three-dimensional structural analysis was performed to estimate the reduction in the yield stress of the bridge. In this study, we attempted to evaluate the unfilled grout quantitatively because it is the main flaw that results in water filling and corrosion. In the measured X-ray images, we obtained gray values, which correspond to the X-ray attenuation coefficients of filled/unfilled grouts, PC wires (steel) in a sheath, and concrete. Then, we compared the ratio of the gray values of the filled/unfilled grouts and PC wires to determine the stage of the unfilled grout. We examined this quantitative evaluation using the data obtained from a real T-shaped PC girder bridge and model samples to simulate thick box-shaped PC girder bridges. We obtained a clear quantitative difference in the ratios for unfilled and filled grouts, which coincided with our visual perception. We synthesized the experience and data and proposed a quantitative analysis for evaluating the unfilled grout for subsequent steps such as structural analysis and destructive evaluation by boring surveys.

The relationships between pelagic larval duration (PLD) and geographic distribution patterns or population genetic structures of fishes remain obscure and highly variable among species. To further understand the early life history of the tidepool snake moray Uropterygius micropterus and the potential relationship between PLD and population genetic structure of this species, otolith microstructure and population genetics based on concatenated mtDNA sequence (cytochrome b and cytochrome oxidase subunit I, 1,336 bp) were analyzed for 195 specimens collected from eight locations around the southern Ryukyu Islands, Taiwan, and the central Philippines. Eels with longer PLD and lower otolith growth rates were observed at relatively higher latitudes with lower water temperatures (54.6 ± 7.7 days and 1.28 ± 0.16 µm day−1 on Ishigaki Island, Japan, vs. 43.9 ± 4.9 days and 1.60 ± 0.19 µm day−1 on Badian, the Philippines), suggesting that leptocephali grew faster and had shortened pelagic periods in warmer waters. Meanwhile, the eels along the southwest coast of Taiwan had relatively longer PLD (57.9 ± 10.5 days), which might be associated with the more complex ocean current systems compared to their counterparts collected along the east coast of Taiwan (52.6 ± 8.0 days). However, the southwestern and eastern Taiwan groups had similar otolith growth rates (1.33 ± 0.19 µm day−1 vs. 1.36 ± 0.16 µm day−1). Despite the intergroup variation in PLD, genetic analysis revealed fluent gene flow among the tidepool snake morays in the study regions, implying that intraspecies PLD variation had a weak effect on genetic structure. The leptocephalus stage might have ensured the widespread gene flow among the study areas and leptocephalus growth was likely influenced by regional water temperature.

Spawning ground of Japanese eel (Anguilla japonica) is located near the West Mariana Ridge seamount. The species travels through the North Equatorial Current (NEC) and then enters the Kuroshio Current (KC) on the migration toward East Asian growth habitats. Therefore, El Niño-Southern Oscillation (ENSO) events serve as the potentially important drivers of interannual variability across the equatorial Pacific. Because the NEC bifurcation and salinity profiles are related to ENSO events, we investigated the influence of locations of the NEC bifurcation and salinity front on the success of larval entry to the KC by numerically modeling particle transport in ocean currents from 1972 to 2013 and possible effects on the size of glass eels at continental recruitment and, via otolithometry on the duration of larval migration. Circulation and hydrography used for particle tracking were obtained from the results of the Model for Interdisciplinary Research on Climate (MIROC) high-resolution forecasting experiment. Our results demonstrated that during El Niño years, (1) the southward movement of the salinity front might cause the larvae to experience slower currents and (2) the northward movement of the NEC bifurcation might broaden the separation between their spawning ground and NEC bifurcation, thus prolonging the time needed for the larvae to enter the KC from their spawning ground, because of which the duration of entrainment in the water column and body size increase when eels reach estuarine waters. In addition, this might cause more water to flow into the Mindanao Current (MC), leading to a decline in the rate at which larvae get entrained into the KC.

Crystal nucleation and growth are first order processes captured in volcanic rocks and record important information about the rates of magmatic processes and chemical evolution of magmas during their ascent and eruption. We have studied glass-rich andesitic tephras from the Central Plateau of the Southern Taupo Volcanic Zone by electron- and ion-microbeam imaging techniques to investigate down to sub-micrometre scale the potential effects of compositional boundary layers (CBLs) of melt around crystals on the nucleation and growth of mineral phases and the chemistry of crystal growth zones. We find that CBLs may influence the types of mineral phases nucleating and growing, and growth textures such as the development of swallowtails. The chemistry of the CBLs also has the capacity to trigger intermittent overgrowths of nanometre-scale bands of different phases in rapidly growing crystals, resulting in what we refer to as cryptic phase zoning. The existence of cryptic phase zoning has implications for the interpretation of microprobe compositional data, and the resulting inferences made on the conditions of magmatic evolution. Identification of cryptic phase zoning may in future lead to more accurate thermobarometric estimates and thus geospeedometric constraints. In future, a more quantitative characterization of CBL formation and its effects on crystal nucleation and growth may contribute to a better understanding of melt rheology and magma ascent processes at the onset of explosive volcanic eruptions, and will likely be of benefit to hazard mitigation efforts.

We report a maximal figure of merit (ZT) value of 1.1 at 600 K was obtained for the sample of which x = 0.03, representing an enhancement greater than 20% compared with a pristine AgSbTe2 sample. This favorable thermoelectric performance originated from the optimal Sn2+ substitution for Sb3+ in AgSbTe2, which not only increased electrical conductivity but also led to a substantial reduction in thermal conductivity that was likely caused by an enhanced phonon-scattering mechanism through the combined effects of lattice defects and the presence of Ag2Te nanoprecipitates dispersed in the matrix.

A gab bro from Chintan, Sindian, was subjected to experiments at atmospheric pressure to study the fractional crystallization of the gabbroic melt. The range of experimental temperatures was from 1120 to 1262°C, and the durations were from about 16 to 150 hours. The mineral phases and the glass compositions in the quenching products were analyzed with the SEM-EDS.

Eclogite compositions are critical parameters for under standing chemical evolution in the Earth, particularly in subduction zones. A group of eclogites from the Sulu ultra-high pres sure (UHP) metamorphic terrane in eastern China shows uncommon petrographic and compositional features. They are characterized by (1) zoisite porphyroblasts coexisting with inclusion-free, inclusion-containing, and net work kyanite, (2) high Al2O3 of 18.4 - 29.2% with high MgO of 8.59 - 11.3%, and (3) intensive HFSE-REE fractionations represented by [Zr/Sm]ch and [Ti/Gd]ch ratios of 0.1 - 3.9 and 1.1 - 9.0, respectively. High-pressure fluids played a major role on developing these features. Kyanite shows two textural varieties. KyI is inclusion-free and in apparent textural equilibrium with gar net and omphacite, implying formation from plagioclase break down. KyII includes kyanite networks and porphyroblasts; the former occurs mostly in gar net, whereas the latter encloses gar net and omphacite grains. KyII were crystallized at the expense of gar net and omphacite during eclogite-fluid interaction. The low [HREE]ch ratios of 1 - 2 indicate that the protoliths were arc cumulates. The well-de fined in verse Al2O3-SiO2 and Al2O3-CaO correlations are not the characteristics of igneous precursors; there fore, must reflect metamorphic modifications. The comparison to mafic cumulates shows that the low-Al samples are compositionally better representatives of protoliths. Mass balance calculations point to anolivine gabbronoritic protolith. The intensive HFSE-REE fractionations reflect compositional differences between two sample groups. Group I samples have superchondritic HFSE-REE ratios [(Nb/La, Zr/Sm, Ti/Gd)ch = 2 - 7] with depletions in LREE. In contrast, group II samples show HFSE depletions and LREE enrichments. These compositional differences were explained as reflecting element mobility during eclogite-fluid inter action. Released at temperatures > 750°C, the high-pres sure flu ids were enriched in HFSE, REE, and LILE. Upon migration, the flu ids first precipitated HFSE into the group I samples, then, LILE and LREE into the group II samples. This model is sup ported by the occurrence of zoisite porphyroblasts in the group II samples, and interstitial zircon and clusters of small rutilegrains along annealed fractures in the group I samples. Our interpretation for the observed compositional variations implies limited element mobility during subduction and exhumation of continental lithosphere, consistent with existing models, which proposed that the chemical flux to metasomatized mantle wedge is mainly from subducted sediments.

We have been developing Laser Ablation Multi-Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS) technique to measure titanium isotopic composition in situ. A principal aim of this work is to search for isotopic heterogeneities larger than the few epsilons (e, in parts in 10^4) of the solar system. Our analytical precision of the ratios of 46Ti, 48Ti, and 50Ti to 49Ti after exponential-law mass discrimination correction normalizing 47Ti/49Ti to 1.33375 were about 2.5 £` (2£m). Mixture solutions were prepared by adding the expected level of Ca, Cr, Mg, and Alto the Ti solutions to demonstrate that our interference correction is effective. We then applied our technique with 213 nm Nd-YAG laser ablation to five Ti-rich terrestrial solids, and all of them also showed titanium isotopic composition that was consistent with one an other and agreed with that for the solution standard. It appears that the in situ laser technique did not significantly in crease the long-term reproducibility be yond the 2.5 established using the solution method. This is an order of magnitude better than the typical precision of a few permil for secondary ion mass spectrometry (SIMS). The combination of the ability to perform in situ analysis on 30 mm spots with e level precision is a niche for LA-MC-ICP-MS. We also ablated two lines on a fassaite grain from a large well studied CAI Egg-6 of the Allende meteorite. After the mass discrimination was corrected by normalizing 47Ti/49Ti, the 46Ti and 48Ti are nor mal within about 2 £ while 50Ti/49Ti shows a 9 £ excess. These data are in excellent agreement with thermalion ization mass spectrometry (TIMS) results. Comparing our ICP-MS results against the results from TIMS studies, we found that our normal titanium isotopic ratios were closest to the less precise data of Heydegger et al. (1979) who measured Ti+. We support the proposal to IUPAC to change the accepted Ti abundance to that measured by ICP-MS and TIMS without using Ti oxides.

The origin of Chinese culture during the Neolithic age has long been a focus of academic debate. The controversy is centered on whether the origins of Neolithic culture in China were singular or more di verse. Con se quently, understanding the spatial distribution of archaeological jade artifacts in the context of the sources of raw jade has been one of the most reason ablemeans to infer the routes of cultural migration and trade activities during the Neo lithic period. It was widely advocated that HeTian Jade from XinJiang was the sole source of jade for all of Neo lithic China. However, the discovery of jade mines at MeiLing (JiangSu Prov ince) in 1989 raises the question as to whether raw jade could have come from an alternate source other than XinJiang during this period. Using 40Ar/39Ar laser dating technique, this study at tempts to correlate the formation ages of excavated jade artifacts at LingJiaTan (AnHui Prov ince) to the nearby MeiLing jade mines and far away HeTian jade mines, in the hope of trac ing the pos si ble cul ture in ter ac tions and trad ing ac tiv i ties among these ar eas. The re sults show that the for ma tion ages of LingJiaTan jade ar ti facts are around 120 Ma, about the same age as jade from the nearby MeiLing jade mines. In addition, both jades are tremolite with similar chemical compositions and mineral characteristics. There fore, the material source of jade artifacts ex cavated at LingJiaTan archeological site most likely originated from these nearby MeiLing jade mines. By contrast, there is a big difference in the formation ages between Meiling jade artifacts and raw HeTian Jade (277.3 Ma). Based on these results, weconclude that in the Neo lithic age, people living in LingJiaTan (AnHui Province) probably had interactions with people around MeiLing (JiangSu Province), but not with peoples of XinJiang Province.

The giant piston core MD01-2387 taken from the eastern Celebes Sea basin provides a marine tephrostratigraphy with higher solution for inferring explosive volcanism in the area surrounding the basin for the past 350 kyr. The sequence contains 65 tephra layers com posed of volcanic minerals and glassy particles. The compositional characteristics of crystal enriched tephra layers and the 87Sr/86Sr of the glass particles (0.7039 to 0.7042) suggest that these ashes were re leased by the volcanoes in the Mindanao-Molucca Sea collision zone, including the south Philippine Arc system, the Sangehi Arc and the Halmahera Arc. The up ward decrease of tephra layers in this core indicates a declining trend of explosive volcanic activity of this collision zone, particularly, after ca. 180 ka in the late Middle Pleistocene. This record also suggests that the shoshonitic volcanism in Central Mindanao be came extinct at ca. 151 ka, which is much younger than what reported previously by onland investigations

Granite from the transition zone of the Huang Yang Dam in the Qilian orogenic belt, NW China, is studied using a high-temperature furnace at atmospheric condition. Twenty-two runs are made to locate the liquidus temperature, the solidus temperature, and the melting interval of the granite of Huang Yang Dam, Gansu Province. The experimental temperatures range from 1010¢XC to 1297¢XC. The duration time is between thirty hours to sixteen days and two hours. Compositions of glass and phenocrysts are analyzed with an electron microprobe.

Pogonophoran tube worms, elongated pyrite tubes and authigenic carbonate nodules are used to evaluate the occurrence of potential cold seeps in the syn-collision accretionary prism Kaoping Slope off SW Taiwan. At least two species of pogonophoran tubeworms were found in surface and core sediments. Pyrites occur in three different forms: fillings inside foraminiferal chambers, cements between calcareous microfossils, and elongated tubes. The bottom water off SW Taiwan is aerobic, but authigenic pyrites are found in the surface sediments at several sites, suggesting the existence of local reducing environments enabling the formation of pyrites. These environments are most likely caused by the occurrence of active cold seeps where methane expulses. Authigenic carbonates with highly depleted carbon isotope values (-54 to -43â°) were found at more than 5 locations, in agreement with a methane-derived source for the carbon.