Os Signatures Research Articles

A Novel Risk Score Model of Lactate Metabolism for Predicting over Survival and Immune Signature in Lung Adenocarcinoma

Simple SummarySince the discovery of the WarBurg effect, the veil of the tumorigenic role of lactic acid has been gradually revealed. Recently, it was proposed that lactic acid that is produced by tumor cells was secreted into the extracellular space to create immunosuppressive tumor microenvironment (TME) in a variety of ways. However, the intersection genes and the association with immunotherapy are unclear. At present, we identified six lactate-metabolism-associated genes, which were thought to enable tumor progression, that were related to LUAD immunotherapy and we constructed an LAR-score risk model. Background: The role of lactate acid in tumor progression was well proved. Recently, it was found that lactate acid accumulation induced an immunosuppressive microenvironment. However, these results were based on a single gene and it was unclear that lactate acid genes were associated with immunotherapy and able to predict overall survival. Methods: Genes and survival data were acquired from TCGA, GEO and GENECARDS. PCA and TSNE were used to distinguish sample types according to lactate metabolism-associated gene expression. A Wilcox-test examined the expression differences between normal and tumor samples. The distribution in chromatin and mutant levels were displayed by Circo and MAfTools. The lactate metabolism-associated gene were divided into categories by consistent clustering and visualized by Cytoscape. Immune cell infiltration was evaluated by CIBERSORT and LM22 matrix. Enrichment analysis was performed by GSVA. We used the ConsensusClusterPlus package for consistent cluster analysis. A prognostic model was constructed by Univariate Cox regression and Lasso regression analysis. Clinical specimens were detected their expression of genes in model by IHC. Results: Most lactate metabolism-associated gene were significantly differently expressed between normal and tumor samples. There was a strong correlation between the expression of lactate metabolism-associated gene and the abundance of immune cells. We divided them into two clusters (lactate.cluster A,B) with significantly different survival. The two clusters showed a difference in signal, immune cells, immune signatures, chemokines, and clinical features. We identified 162 differential genes from the two clusters, by which the samples were divided into three categories (gene.cluster A,B,C). They also showed a difference in OS and immune infiltration. Finally, a risk score model that was composed of six genes was constructed. There was significant difference in the survival between the high and low risk groups. ROC curves of 1, 3, 5, and 10 years verified the model had good predictive efficiency. Gene expression were correlated with ORR and PFS in patients who received anti-PD-1/L1. Conclusion: The lactate metabolism-associated genes in LUAD were significantly associated with OS and immune signatures. The risk scoring model that was constructed by us was able to well identify and predict OS and were related with anti-PD-1/L1 therapy outcome.

Osmium isotope evidence for rapid melt migration towards the Moho in the Oman ophiolite

The oceanic crust, covering two-thirds of the Earth's surface, is formed along mid-oceanic ridges by crystallization at shallow levels of melts formed at depth by partial melting of mantle peridotite. Yet, the process of melt transport to the ridge axis remains poorly understood. Ophiolites, which provide a window into the uppermost mantle, contain dunite bodies often interpreted as relics of melt flow conduits, formed by pyroxene dissolution during melt-peridotite interaction. Here, we present structural and geochemical data on peridotites from the southeastern Oman ophiolite where three types of dunite, corresponding to the Moho transition zone (MTZ), the main and basal mantle sections, are identified. We focus on osmium isotopes, which are particularly well-adapted to tracing melt flow through peridotites. Osmium isotope signatures from host harzburgites accord with abyssal peridotite values and do not vary systematically with setting. In contrast, dunite Os compositions depend on structural context. Basal dunites display compositions similar to harzburgite values, while MTZ dunites have highly radiogenic compositions similar to those of the overlying crust, requiring extensive interaction with melts more radiogenic than MORB. Modeling shows that melts percolating through and equilibrating with dunite channels would acquire unradiogenic compositions, inconsistent with the observed Os signatures of MTZ dunites and lower crust. Thus, our findings require melt transport without equilibration with dunite or harzburgite, arguing for rapid or at least chemically isolated melt migration from the mantle source to the Moho.

Osmium isotopic constraints on sulphide formation in the epithermal environment of magmatic-hydrothermal mineral deposits

In the magmatic-hydrothermal environment, fluids with similar metal concentrations and sources may yield contrasting mineral assemblages in successive stages of sulphide mineralization. These differences are linked to the physico-chemical conditions of the mineralizing fluids (e.g., T, pH, fS2, fO2) acquired during their interaction with country rocks and/or by mixing with groundwater. Here, we integrate petrography and osmium (Os) isotope (187Os/188Os) sulphide geochemistry, and discuss novel constraints on magmatic fluid-rock interaction and magmatic fluid-groundwater mixing that are deemed to govern sulphide deposition in magmatic-hydrothermal systems. We studied pyrite (FeS2) and enargite (Cu3AsS4) from the porphyry-related polymetallic Cerro de Pasco (14.54–14.41 Ma) and Colquijirca (10.83–10.56 Ma) epithermal deposits in the Central Andes, Peru. Sulphide mineralization is genetically associated with Miocene magmatism and includes breccia and replacement bodies of carbonate country rocks, and veins cutting the magmatic and sedimentary country rocks.At both deposits, pyrite is followed by enargite in the paragenesis. Pyrite has a radiogenic initial 187Os/188Os isotopic composition (187Os/188Osi-pyrite or Osi-pyrite = 0.80 to 1.45). Enargite (I) enclosing pyrite or filling in cracks in pyrite also has a radiogenic initial 187Os/188Os isotopic composition (Osi-enargite I = 0.56 to 1.24). Conversely, enargite (II) that formed on irregular surfaces on earlier pyrite has an unradiogenic 187Os/188Os isotopic composition (Osi-enargite II = 0.13 to 0.17). Our data show that the paragenetic evolution from pyrite to enargite records a sharp change in the osmium isotope composition within these sulphides.Pyrite and enargite (I) record radiogenic initial 187Os/188Os isotopic compositions, indicating interaction of magmatic hydrothermal fluids with the sedimentary country rocks. However, the unradiogenic initial 187Os/188Os isotopic composition of enargite (II) suggests that magmatic fluids with a mantle-like 187Os/188Os signature ascended from parental magmatic chambers to the epithermal environment without incorporation of crustal Os via fluid-rock interaction or mixing with groundwater. This difference may be due to the country rocks being altered during previous stages, with the radiogenic crustal Os signature being flushed by earlier magmatic pulses. Our findings imply that ore metals (i.e., Cu, Au) are magma-derived, whereas the Os isotopic composition of pyrite and some enargite in epithermal deposits may capture the signature of the interaction of magmatic fluids with country rock lithologies (e.g., the Eifelian black shale in the study area) and/or groundwater. Thus, the isotopic composition of the siderophile and chalcophile trace element Os in sulphides may act as a tracer of metal source, and degree of wall-rock interaction.

Os isotopic constraints on crustal contamination in Auckland Volcanic Field basalts, New Zealand

The Auckland Volcanic Field (AVF) represents the youngest and northernmost of three subjacent Quaternary intraplate basaltic volcanic fields in the North Island, New Zealand. Previous studies on AVF eruptive products suggested that their major- and trace-element, and Sr-, Nd- and Pb-isotopic signatures primarily reflect their derivation from the underlying asthenospheric and lithospheric mantle. All AVF lavas however ascend through a ca. 20–30km thick continental crust, and some do carry crustal xenoliths, posing the question whether or not crustal contamination plays a role in their formation. Here we present new Os and Pb isotopic data, and Os and Re concentrations for 15 rock samples from 7 AVF volcanic centres to investigate mantle and crustal petrogenetic processes. The samples include the most primitive lavas from the field (Mg# 59–69) and span a range of eruption sizes, ages, locations, and geochemical signatures. The data show a large range in Os concentrations (6–579ppt) and 187Os/188Os isotope ratios from mantle-like (0.123) to highly radiogenic (0.547). Highly radiogenic Os signatures together with relatively low Os contents in most samples suggest that ascending melts experienced contamination primarily from metasedimentary crustal rocks with high 187Os/188Os ratios (e.g., greywacke). We further demonstrate that <1% metasedimentary crustal input into the ascending melt can produce the radiogenic Os isotope signatures observed in the AVF data. This low level of crustal contamination has no measurable effect on the corresponding trace element ratios and Sr-Nd-Pb isotopic compositions. In addition, high Os contents (195–578ppt) at slightly elevated but mantle-like Os isotopic compositions (187Os/188Os=0.1374–0.1377) in some samples suggest accumulation of xenocrystic olivine-hosted mantle sulphides from the Permian-Triassic ultramafic Dun Mountain Ophiolite Belt, which traverses the crust beneath the Auckland Volcanic Field. We therefore infer that the AVF Os isotopic compositions and Os contents reflect contamination from varying proportions of heterogeneous crustal components, composed of Waipapa and Murihiku terrane metasediments, and ultramafic rocks of the Dun Mountain Ophiolite Belt. This demonstrates, contrary to previous models that primitive lavas from the Auckland Volcanic Field do show evidence for variable interaction with the crust.

Re-Os pyrite geochronology of Zn-Pb mineralization in the giant Caixiashan deposit, NW China

The newly discovered Caixiashan Irish-type Zn-Pb deposit (∼131 Mt at 3.95 % Zn + Pb), located in the Eastern Tianshan of Xinjiang, is one of the largest Zn-Pb deposits in NW China. Massive colloform/framboidal textured syn-sedimentary pyrite yielded a Re-Os isochron age of 1019 ± 70 Ma (MSWD = 3.5), which is interpreted to be the depositional age of the Kawabulake group that hosts the ore. The age of the main mineralization stage is constrained by two types of pyrite: the layered pyrite coexists with recrystallized calcite and dolomite and is locally replaced by sphalerite, whereas the euhedral pyrite occurs with galena that crosscuts the massive sphalerite. The layered pyrite yielded a Re-Os age of 859 ± 79 Ma (MSWD = 6.7; initial 187Os/188Os ratio [IOs] = 0.19 ± 0.25) and the euhedral pyrite 837 ± 39 Ma (MSWD = 6.5; [IOs] = 0.16 ± 0.09), which are interpreted to be the Zn and Pb mineralization ages, respectively. The low radiogenic initial Os values of the Zn-Pb mineralization suggest interaction between a hydrothermal fluid and a mafic or ultramafic source rock with a mantle Os signature with some contamination with Mesoproterozoic Kawabulake group. Based on our new Re-Os ages, we conclude that the giant Caixiashan Zn-Pb deposit formed in the early Neoproterozoic and it represents a newly identified mineralization epoch in the Eastern Tianshan of the Central Asia Orogenic Belt.

Rhenium-osmium isotope fractionation at the oceanic crust-mantle boundary

It has been proposed that the oceanic crust-mantle boundary may partly form through interactions between melts and the shallow mantle. Although this process may have a key role in defining the chemical signature of the oceanic crust, the effect of such melt-mantle interactions on the isotopic composition of the reacting melts has rarely been investigated. Here we report Re-Os isotopes and platinum group element (PGE) compositions of residual mantle harzburgites (olivine forsterite, Fo 91–90 ) and troctolites (olivine Fo 89–87 ) likely produced by melt-rock reactions at the Central Indian Ridge crust-mantle boundary. Although the harzburgites have high Os (4000–2500 pg/g) and unradiogenic isotopic signatures ( 187 Os/ 188 Os = 0.128–0.124), the troctolites show variable Os (383–16 pg/g) and highly fractionated 187 Os/ 188 Os ratios (0.129–0.140), which correlate with mineral (e.g., olivine Fo) and bulk-rock (e.g., CaO, Ni, and Cu) compositions. We relate this isotopic variability to the melt-mantle interaction process by which the troctolites generated. In particular, we suggest that the radiogenic Os signature was produced by selective assimilation of radiogenic interstitial sulfides from the reacted mantle. This mechanism is able to mimic the isotope variability of erupted melts, sustaining the idea that the crust-mantle boundary can act as a reactive filter for the melts extracted from the source region.

Significance of ancient sulfide PGE and Re–Os signatures in the mantle beneath Calatrava, Central Spain

Spinel lherzolite and wehrlite xenoliths from the Cenozoic Calatrava volcanic field carry the geochemical imprint of metasomatic agents that have affected the subcontinental lithospheric mantle beneath Central Iberia. Some xenoliths (mainly wehrlites) were enriched in REE, Sr, P, and CO2 by silicic-carbonate-rich metasomatic melts/fluids, while others record the effects of subduction-related hydrous silicate fluids that have precipitated amphibole and induced high Ti/Eu in primary clinopyroxene. The petrographic observations and geochemical data suggest that interstitial glass in the xenoliths represent the quenched products of Si-rich melts that infiltrated the mantle peridotite shortly before the entrainment of the xenoliths in the host magmas that erupted ca 2 million years ago. During their infiltration, the metasomatic melts reacted with peridotite, resulting in silica enrichment, while remobilizing grains of iron-rich monosulfide solid solution (Fe-rich Mss) initially enclosed in, or intergranular to, primary olivine and pyroxenes. In situ laser ablation inductively coupled plasma-mass spectrometry analysis of single sulfide grains reveals that the Fe-rich Mss in glass shows platinum-group element (PGE) patterns and 187Os/188Os compositions identical to the Fe-rich Mss occurring as inclusions in, or at grain boundaries of primary silicates. Moreover, independent of its microstructural position, Fe-rich Mss exhibits PGE and 187Os/188Os signatures typical of Mss either residual after partial melting or crystallized directly from sulfide melts. Our findings reveal that young metasomatic melt(s)/fluid(s) may carry remobilized sulfides with PGE and Os-isotopic signatures identical to those of texturally older sulfides in the peridotite xenolith. These sulfides thus still provide useful information about the timing and nature of older magmatic events in the subcontinental mantle.

Evidence for mixing of Re–Os isotopes at < 2.7 Ga and support of a remobilized placer model in Witwatersrand sulfides and native Au

This study analyzes Re and Os contents of Au rich sulfides from the Carbon Leader (Tau Lekoa and Mponeng), the VCR (Mponeng and Tau Lekoa), and the Black Reef (Modder East), as well as native Au in the Carbon Leader, to further investigate the detrital (placer), modified detrital (placer), and hydrothermal models for the source of Au in mines from the Witwatersrand. An isochron plot of the results from the four locations yields an imprecise isochron age of 2381±140Ma (MSWD=17) and initial 187Os/188Os=0.24±0.21. Isochron plots for the individual reefs also yielded ages that are younger than the deposition of the basin Witwatersrand sediments. Samples that possess higher concentrations of Os (>100ppb) and low 187Re/188Os ratios (<0.02) yield model ages of the same age or older than the basin formation (2820 to 3270Ma).To unify all of the data providing a large variation of chronologic information, Os mixing diagrams for both gold and sulfide minerals produce realistic mixing trends when solving Os initial ratios for 2050Ma. The two most probable end members for the mixing relationships are a high Os concentration non-radiogenic source and a low Os concentration highly radiogenic source. The high concentration non-radiogenic Os source has been measured in multiple studies and has been clearly derived from the subcontinental lithospheric mantle (SCLM). The low concentration, highly radiogenic source is debatable. The measured concentrations of Os in the Witwatersrand ores are much greater than published Os concentrations in other hydrothermal ores. The data could indicate a redistribution of the detrital Os signatures at 2050Ma; thus a modified detrital model best explains the previously published data and this data.

The role of recycled oceanic crust in magmatism and metallogeny: Os–Sr–Nd isotopes, U–Pb geochronology and geochemistry of picritic dykes in the Panzhihua giant Fe–Ti oxide deposit, central Emeishan large igneous province, SW China

The picritic dykes occurring within fine-grained gabbro in the marginal zone and in the surrounding Proterozoic wall-rock marbles of the Panzhihua Fe–Ti oxide deposit closely correspond in bulk composition with the nearby Panzhihua intrusion. These dykes offer important constraints on the nature of the mantle source of the Panzhihua ore-bearing intrusion and its possible link to the Emeishan plume. U–Pb zircon dating of the picritic dyke yields a crystallization age of 261.4 ± 4.6 Ma, coeval with the timing of the main Panzhihua gabbroic intrusion and Late Permian Emeishan flood basalts. The Panzhihua picritic dykes contain 37.63–43.41 wt% SiO2, 1.15–1.56 wt% TiO2, 11.43–13.25 wt% TFe2O3, and 20.96–28.87 wt% MgO. Primitive-mantle-normalized patterns of the rocks are comparable to those of ocean island basalt. The rocks define a relatively small range of Os isotopic compositions and a low Os signature of −0.13 to +2.76 for γOs (261 Ma). In combination with their Sr–Nd–Os isotopic compositions, we interpret that these rocks were derived from the Emeishan plume sources as well as the interactions of plume melts with the overlying lithosphere which had been extensively affected by eclogite-derived melts from the deep-subducted oceanic slab. Partial melting induced by an upwelling mantle plume that involved an eclogite or pyroxenite component in the lithospheric mantle could have produced the parental Fe-rich magma. Our study suggests that plume-lithosphere interaction might have played a key role in generating many world-class Fe–Ti oxide deposits clustered in the Panxi area.

Osmium behavior in a subduction system elucidated from chromian spinel in Bonin Island beach sands

Research Article| November 01, 2011 Osmium behavior in a subduction system elucidated from chromian spinel in Bonin Island beach sands Katsuhiko Suzuki; Katsuhiko Suzuki * 1Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine Earth Science and Technology (JAMSTEC), 2-15 Natsushima, Yokosuka 237-0061, Japan2Precambrian Ecosystem Laboratory, Japan Agency for Marine Earth Science and Technology (JAMSTEC), 2-15 Natsushima, Yokosuka 237-0061, Japan *E-mail: katz@jamstec.go.jp. Search for other works by this author on: GSW Google Scholar Ryoko Senda; Ryoko Senda 1Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine Earth Science and Technology (JAMSTEC), 2-15 Natsushima, Yokosuka 237-0061, Japan Search for other works by this author on: GSW Google Scholar Kenji Shimizu Kenji Shimizu 1Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine Earth Science and Technology (JAMSTEC), 2-15 Natsushima, Yokosuka 237-0061, Japan2Precambrian Ecosystem Laboratory, Japan Agency for Marine Earth Science and Technology (JAMSTEC), 2-15 Natsushima, Yokosuka 237-0061, Japan Search for other works by this author on: GSW Google Scholar Geology (2011) 39 (11): 999–1002. https://doi.org/10.1130/G32044.1 Article history received: 05 Jan 2011 rev-recd: 17 May 2011 accepted: 24 May 2011 first online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Katsuhiko Suzuki, Ryoko Senda, Kenji Shimizu; Osmium behavior in a subduction system elucidated from chromian spinel in Bonin Island beach sands. Geology 2011;; 39 (11): 999–1002. doi: https://doi.org/10.1130/G32044.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract The Os isotopic system is a potential tracer of a recycled crustal component in mantle or volcanic rocks because of the significant contrast between Os isotope ratios of crust and mantle. However, the potential for crustal contamination overprinting this possible signal has hampered the utility of Os isotopic ratios. We explored the use of Os isotopes in chromian spinel (Cr-spinel) as a discriminator of primitive magma Os compositions in the Izu-Bonin arc, using beach sands as composite samples of the boninite and tholeiite magmas in three different islands. Cr-spinel is an early-stage crystal that preserves its isotopic composition even during later crustal contamination of the bulk rock. We found highly unradiogenic Os isotopic compositions in Cr-spinels from boninites, suggesting that they represent primitive magmas with slight or no Os contribution from the subducting slab during the generation of boninites in the infant arc stage (48–46 Ma). Conversely, the radiogenic Os isotopic ratios in Cr-spinels from tholeiites most likely reflect the contribution from a slab-derived component, because more oxidative conditions in the subarc mantle probably allowed Os to mobilize from the subducting slab during the transitional arc stage (45–41 Ma). Although shallow-level assimilation of crustal components with radiogenic Os may overprint the original Os signature of tholeiite magma during its ascent, Cr-spinel allows us to compensate such possibilities. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Preservation of ancient Os isotope signatures in the Yungbwa ophiolite (southwestern Tibet) after subduction modification

Both spinel and plagioclase harzburgites from the Yungbwa ophiolite, southwestern Tibet, have been studied for highly siderophile elements (HSEs) and Re–Os isotopes. The spinel harzburgites can be subdivided into low-Cr# and high-Cr# groups, according to the spinel Cr#. The low-Cr# harzburgites have been estimated to experience with ca. 13% degrees of partial melting, whereas the high-Cr# harzburgites have been subjected to 16–18% degrees of melting. Clinopyroxenes in the low-Cr# harzburgites show depleted REE patterns, indicating they have been negligibly modified by melts. In contrast, both high-Cr# and plagioclase harzburgites have been metasomatized to different extents, as evidenced by the variable enrichment of LREE in their clinopyroxenes. Compositions of the metasomatic agents are of affinities to the subduction-related magmas. The low-Cr# harzburgites have equilibrium temperatures higher than both high-Cr# and plagioclase harzburgites. We explain that the low-Cr# harzburgites represent mantle residues after melt extraction at mid-ocean ridge (MOR), whereas both high-Cr# and plagioclase harzburgites were originated from the supra-subduction zone (SSZ) settings. These different types of mantle peridotites were tectonically juxtaposed during the emplacement of the Yungbwa ophiolite. The low-Cr# harzburgites display consistent highly siderophile element (HSE) patterns with suprachondritic Ru/Ir and Pd/Ir ratios, whereas both high-Cr# and plagioclase harzburgites show fractionated HSE patterns. A high-Cr# harzburgite, GHP-86, is strongly depleted in both Pd and Re. The Yungbwa harzburgites have variable 187Os/188Os ratios ranging from 0.12228 to 0.12876. Sample GHP-86 has the less radiogenic 187Os/188Os ratio, giving a depletion age (TRD) of ∼1Ga. The Re–Os isotope compositions of different types of the Yungbwa harzburgites suggest that their 187Os/188Os ratios have not been remarkably modified by subduction-related melts. Furthermore, subduction modification has not erased the ancient Os signatures in the Yungbwa peridotites. The reason is probably because the primary unradiogenic Os in the Yungbwa harzburgites had not been significantly reduced during the metasomatism. The asthenospheric mantle beneath the Neo-Tethys Ocean, from which the Yungbwa ophiolite was derived, had heterogeneous Os isotope compositions and contained some ancient mantle domains.

실시간 트래픽 분석을 위한 운영체제 판별 방법에 관한 연구

현대인의 삶에서 인터넷은 다양한 정보를 제공하는 필수 요소가 되었다. 이에 따라 네트워크 트래픽은 폭발적으로 증가하였고, 효율적 네트워크 관리를 위해 네트워크 트래픽 분석의 중요성이 강조되고 있다. 네트워크 트래픽 분석 방법 중 시그니쳐 기반의 분석 방법론이 많이 사용되고 있으며, 이는 다양한 응용의 증가로 시그니쳐의 탐색 공간 증가에 따라 실시간 트래픽 분석에 문제점이 나타나고 있다. 운영체제 정보를 활용하면 해당 운영체제에서 사용되는 응용의 시그니쳐만을 검색하도록 함으로써 앞선 문제점을 해결할 수 있다. 본 논문에서는 실시간 트래픽 분석을 위한 효과적인 운영체제 판별 방법을 제안한다. 본 논문에서 제안하는 운영체제 판별 방법은 실시간 트래픽 분석에 적합한 가볍고 빠른 수동형 방법을 사용하였으며, 기존 수동형 방법이 가지는 분석률과 정확성이 낮은 문제를 해결하였다. 분석률을 향상시키기 위해 입력데이터를 확장시켰으며, 운영체제 판별을 위한 시그니쳐를 HTTP의 User-Agent를 이용하여 생성함으로써 다양한 운영체제에 대한 시그니쳐를 추출하였다. 또한 기존 패킷 기반의 분석을 플로우 단위의 분석으로 변경함으로써 정확성을 향상시켰다. The Internet has become an essential part in our modern life by providing useful information. So, the volume of Internet traffic has been increasing rapidly, which emphasizes the importance of network traffic analysis for effective network operation and management. Signature based analysis have been commonly used, but it is shown that the increase of signatures due to the increase of applications causes the performance degradation of real-time traffic analysis on high-speed network links. In this paper, we propose OS fingerprinting method for real-time traffic analysis. The previous problems can be solved by utilizing the OS information. The OS fingerprinting method for real-time traffic analysis, proposed in this paper, conducts under passive mode, and improves the limitation of a previous method such as low completeness and accuracy. In this paper, we enlarged an input data to improve completeness, and used the User-Agent field in HTTP packet to extract various OS signatures. Also, we changed an input data from packet to flow to improve accuracy.

Persistence of mantle lithospheric Re–Os signature during asthenospherization of the subcontinental lithospheric mantle: insights from in situ isotopic analysis of sulfides from the Ronda peridotite (Southern Spain)

The western part of the Ronda peridotite massif (Southern Spain) consists mainly of highly foliated spinel-peridotite tectonites and undeformed granular peridotites that are separated by a recrystallization front. The spinel tectonites are interpreted as volumes of ancient subcontinental lithospheric mantle and the granular peridotites as a portion of subcontinental lithospheric mantle that underwent partial melting and pervasive percolation of basaltic melts induced by Cenozoic asthenospheric upwelling. The Re–Os isotopic signature of sulfides from the granular domain and the recrystallization front mostly coincides with that of grains in the spinel tectonites. This indicates that the Re–Os radiometric system in sulfides was highly resistant to partial melting and percolation of melts induced by Cenozoic lithospheric thermal erosion. The Re–Os isotopic systematics of sulfides in the Ronda peridotites thus mostly conserve the geochemical memory of ancient magmatic events in the subcontinental lithospheric mantle. Os model ages record two Proterozoic melting episodes at ~1.6 to 1.8 and 1.2–1.4 Ga, respectively. The emplacement of the massif into the subcontinental lithospheric mantle probably coincided with one of these depletion events. A later metasomatic episode caused the precipitation of a new generation of sulfides at ~0.7 to 0.9 Ga. These Proterozoic Os model ages are consistent with results obtained for several mantle suites in Central/Western Europe and Northern Africa as well as with the Nd model ages of the continental crust of these regions. This suggests that the events recorded in mantle sulfides of the Ronda peridotites reflect different stages of generation of the continental crust in the ancient Gondwana supercontinent.

Rhenium–osmium systematics of the Mount Isa copper orebody and the Eastern Creek Volcanics, Queensland, Australia: implications for ore genesis

The syn-tectonic breccia-hosted Mount Isa Cu deposit in northwest Queensland is the largest sediment-hosted Cu deposit in Australia. Whole-rock samples of chalcopyrite-rich Cu ore form an isochron with a Re–Os age of 1,372 ± 41 Ma. This age is more than 100 Ma younger than the previously accepted age of Cu ore formation, an Ar–Ar mineral age for biotite separated from the host rocks within the alteration envelope to the Cu orebody. This discrepancy cannot be unequivocally resolved due to a lack of other absolute geochronological constraints for Cu mineralisation or the deformation event associated with Cu emplacement. The 1,372 ± 41 Ma date may reflect (a) the time of Cu deposition, (b) the time of a hydrothermal event that reset the Re–Os signature of the Cu ore or (c) mixing of the Re–Os isotope systematics between the host rocks and Cu-bearing fluids. However, a range of published Ar–Ar and Rb–Sr dates for potassic alteration associated with Cu mineralisation also records an event between 1,350 and 1,400 Ma and these are consistent with the 1,372 Ma Re–Os age. The 1.8 Ga Eastern Creek Volcanics are a series of tholeiitic basalts with a primary magmatic Cu enrichment which occur adjacent to the Mount Isa Cu deposit. The whole-rock Os isotopic signature of the Eastern Creek Volcanics ranges from mantle-like values for the upper Pickwick Member, to more radiogenic/crustal values for the lower Cromwell Member. The Re–Os isotope signature of the Cu ores overlaps with those calculated for the two volcanic members at 1,372 Ma; hence, the Os isotope data are supportive of the concept that the Os in the Cu ores was sourced from the Eastern Creek Volcanics. By inference, it is therefore postulated that the Eastern Creek Volcanics are the source of Cu in the Mount Isa deposit, as both Os and Cu are readily transported by oxidised hydrothermal fluids, such as those that are thought to have formed the Cu orebody. The Pickwick Member yields a Re–Os isochron age of 1,833 ± 51 Ma, which is within error of previously reported age constraints. The initial 187Os/188Os isotopic ratio of 0.114 ± 0.067 (γOs = −0.7) is slightly subchondritic, and together with other trace element geochemical constraints, is consistent with a subcontinental lithospheric mantle source. The Pickwick Member records a minimum age of ca. 1.95 Ga for melt depletion in the subcontinental lithospheric mantle beneath the Mount Isa Inlier prior to the extraction of the magmas which formed the Eastern Creek Volcanics. This corresponds with the end of subduction-related magmatism along the eastern margin of the Northern Australian Craton, which included the Mount Isa Inlier.

Diverse contributing sources to chromitite petrogenesis in the Shebenik Ophiolitic Complex, Albania: evidence from new PGE- and Os-isotope data

Chromitites sampled from four different pseudostratigraphic levels of the Mesozoic Shebenik Ophiolite Complex, Albania, have low PGE totals 0.75) and low titanium contents of chromites throughout the sample suite are consistent with chromitite petrogenesis in a SSZ environment. Shebenik mantle chromitites with low 187Re/188Os ratios have an average, slightly suprachondritic initial osmium isotopic composition of 0.1285 ± 0.0022 (2s). Towards higher pseudostratigraphic levels, 187Re/188Os ratios increase and initial Os isotopies are very heterogeneous. Distinctly suprachondritic Os signatures require input of radiogenic source components, whereas subchondritic samples require assimilation of long term Re-depleted PGM.

Os, Pb, and Nd isotope geochemistry of the Permian Emeishan continental flood basalts: Insights into the source of a large igneous province

The nature of the source of continental flood basalts (CFB) is a highly debated topic. Proposed mantle sources for CFBs, including both high- and low-Ti basalts, include subcontinental lithospheric mantle (SCLM), asthenospheric mantle, and deep, plume-related mantle. Re–Os isotope systematics can offer important constraints on the sources of both ocean island basalts (OIB) and CFB, and may be applied to distinguish different possible melt sources. This paper reports the first Re–Os isotope data for the Late Permian Emeishan large igneous province (LIP) in Southwest China. Twenty one CFB samples including both low- and high-Ti basalts from five representative sites within the Emeishan LIP have been analyzed for Os, Nd, and Pb isotopic compositions. The obtained Os data demonstrate that crustal assimilation affected Os isotopic compositions of some Emeishan basalt samples with low Os concentrations but not all of the samples, and the Emeishan basalts with high Os contents likely experienced the least crustal contamination. The low and high-Ti basalts yield distinct Os signatures in terms of 187Os/ 188Os and Os content. The low-Ti basalt with the highest Os concentration (400 ppt) has a radiogenic Os isotopic composition (γOs( t), +6.5), similar to that of plume-derived OIB. Because the Os isotopic composition of basalts with relatively high Os concentrations (typically >50 ppt) likely represents that of their mantle source, this result implies a plume-derived origin for the low-Ti basalts. On the other hand, the high-Ti basalts with high Os concentration (over 50 ppt) have unradiogenic Os isotopic signatures (γOs( t) values range from −0.8 to −1.4), suggesting that a subcontinental lithosphere mantle (SCLM) component most likely contributed to the generation of these magmas. Combining Pb and Nd isotopic tracers with the Os data, we demonstrate that the low-Ti basaltic magmas in the Emeishan CFB were mainly sourced from a mantle plume reservoir, whereas the high-Ti basaltic magmas were most likely derived from a SCLM reservoir or were contaminated by a significant amount of lithospheric mantle material during plume-related magma ascent through the SCLM.

A subduction wedge origin for Paleoarchean peridotitic diamonds and harzburgites from the Panda kimberlite, Slave craton: evidence from Re–Os isotope systematics

An extensive study of peridotitic sulfide inclusion bearing diamonds and their prospective harzburgitic host rocks from the 53 Ma Panda kimberlite pipe, Ekati Mine, NWT Canada, has been undertaken with the Re–Os system to establish their age and petrogenesis. Diamonds with peridotitic sulfide inclusions have poorly aggregated nitrogen (<30% N as B centers) at N contents of 200–800 ppm which differs from that of chromite and silicate bearing diamonds and indicates residence in the cooler portion of the Slave craton lithospheric mantle. For most of the sulfide inclusions, relatively low Re contents (average 0.457 ppm) and high Os contents (average 339 ppm) lead to extremely low 187Re/188Os, typically << 0.05. An age of 3.52 ± 0.17 Ga (MSWD = 0.46) and a precise initial 187Os/188Os of 0.1093 ± 0.0001 are given by a single regression of 11 inclusions from five diamonds that individually provide coincident internal isochrons. This initial Os isotopic composition is 6% enriched in 187Os over 3.5 Ga chondritic or primitive mantle. Sulfide inclusions with less radiogenic initial Os isotopic compositions reflect isotopic heterogeneity in diamond forming fluids. The harzburgites have even lower initial 187Os/188Os than the sulfide inclusions, some approaching the isotopic composition of 3.5 Ga chondritic mantle. In several cases isotopically distinct sulfides occur in different growth zones of the same diamond. This supports a model where C–O–H–S fluids carrying a radiogenic Os signature were introduced into depleted harzburgite and produced diamonds containing sulfides conforming to the 3.5 Ga isochron. Reaction of this fluid with harzburgite led to diamonds with less radiogenic inclusions while elevating the Os isotope ratios of some harzburgites. Subduction is a viable way of introducing such fluids. This implies a role for subduction in creating early continental nuclei at 3.5 Ga and generating peridotitic diamonds.

Slab devolatilization and Os and Pb mobility in the mantle wedge of the Kamchatka arc

Os-, Nd-, and Pb-isotope measurements were performed on a suite of eleven Kamchatka peridotite mantle xenoliths in volcanics from the southern (Avachinsky) and central (Sheveluch and Kharchinsky) segments of the Kamchatka peninsula. Peridotites with higher Os content (1.3–5.2 ppb) show a narrow 187Os / 188Os range between 0.1182 and 0.1272 while the xenoliths with lower Os content (< 1 ppb) show a wider variation and more radiogenic 187Os / 188Os values (0.1287–0.1585). 187Os / 188Os and 3He / 4He ( R / R a) values of the xenoliths indicate that the xenoliths are metasomatized by the slab-derived fluids from the subducting altered oceanic crust. The original Os signature of some of the mantle wedge xenoliths seems to be eradicated and imprinted by the slab fluids from the subducting crust. The Nd-isotopic (+ 8.7–+ 9.3) and Pb-isotopic ratios ( 206Pb / 204Pb = 18.25–18.76; 207Pb / 204Pb = 15.43–15.55; 208Pb / 204Pb = 37.68–38.24) of the xenoliths are similar to those of the Pacific MORB. Pb and Ba contents of the xenoliths increase with increasing 187Os / 188Os. Thus the mantle-wedge beneath Kamchatka was infiltrated by slab-derived fluids with Os, Pb, and other volatile and fluid-mobile elements.

Highly siderophile element geochemistry of 187Os-enriched 2.8 Ga Kostomuksha komatiites, Baltic Shield

New analyses of highly siderophile elements (HSE; Re, Os, Ir, Ru, Pt, and Pd) obtained by Carius tube digestion isotope dilution inductively coupled plasma mass-spectrometry (ID-ICPMS) technique are reported for 187Os-enriched 2.8 Ga komatiites from the Kostomuksha greenstone belt. As a result of a significant improvement in the yield over our previous digestions by the NiS fire-assay technique, these komatiites have now been shown to contain 22 to 25% more Os, Ir, and Pt and 34% more Ru. The emplaced komatiite lavas at Kostomuksha thus had siderophile element abundances comparable to those of the Abitibi belt. The discrepancies observed between the two techniques are interpreted to be the result of incomplete digestion of HSE carriers (particularly chromite) during the NiS fire-assay procedure. Our results for UB-N peridotite reference material agree well with those obtained by the high-pressure ashing digestion ID-ICPMS technique reported in the literature. Two types of komatiite lavas have been distinguished in this study based on the IPGE (Os, Ir, and Ru) behavior during lava differentiation. The Kostomuksha type is unique and is characterized by an incompatible behavior of IPGEs, with bulk solid-liquid partition coefficients for IPGEs being close to those for olivine. Cumulate zones in this type of komatiite lava occupy <20% of the total thickness of the flows. The Munro type exhibits a compatible behavior of IPGEs during lava differentiation. The cumulate zone in this type of komatiite occupies >20% of the total thickness of the flows. The calculated bulk partition coefficients indicate that, as with the other Munro-type komatiite lavas, the bulk cumulate contained an IPGE-rich minor phase(s) in addition to olivine. The non-CI chondritic HSE pattern for the source of the Kostomuksha komatiites calculated here is similar to that of Abitibi komatiites and to average depleted spinel lherzolite (ADSL) and supports the hypothesis of a non-CI chondritic HSE composition of the Earth’s mantle. The absolute HSE abundances in the source of the Kostomuksha komatiite have been demonstrated to be comparable to those of the source of Abitibi komatiites, even though the two komatiites contrast in their Os isotopic compositions. This supports the earlier hypothesis that if core-mantle interaction produced the 187Os/ 188Os radiogenic signature in the Kostomuksha source, it must have occurred in the form of isotope exchange at the core-mantle boundary. Other explanations of the radiogenic Os signature are similarly constrained to conserve the elemental abundance pattern in the mantle source of Kostomuksha komatiites.

Sources and genesis of the Chinkuashih Au–Cu deposits in northern Taiwan: constraints from Os and Sr isotopic compositions of sulfides

The Chinkuashih district at northern Taiwan hosts one of the largest Au deposits in the western Pacific gold province. Gold were precipitated from hydrothermal solutions as native gold or incorporated into sulfides at a temperature range of 200–350 °C. The sulfides in ore mines have 187Os/ 188Os ratios varying from 0.139 to 0.249. The positive 187Os/ 188Os–1/Os correlation is consistent with derivation from the hybrid fluids containing various proportions of mantle and crustal components. The crustal component was the meteoric water that had acquired its Sr and Os isotopic signatures from the local sedimentary formations and dacitic intrusions. The mantle component was the magmatic fluid segregated from the dacitic magma by fractional crystallization. Based on the 187Os/ 188Os–1/Os correlation, the hybrid fluids forming the Chinkuashih sulfides contained less than 30% magmatic fluid, except for one sulfide sample from Hsumei, which required >40% magmatic fluid. Compared to meteoric water, the magmatic fluid contained a higher Os content (130 times higher) and was enriched in Os relative to Sr with an Os/Sr ratio two orders higher than that of the crustal fluid. Consequently, the Os budget in the hybrid fluids was controlled by the magmatic fluid, although the meteoric water was volumetrically dominated. If gold and Os behave similarly in chemistry, the Chinkuashih gold deposits are of mantle origin and the area where sulfides with the greatest mantle Os signature may host undiscovered gold deposits. Finally, the 187Os/ 188Os ratios of sulfides show no relationship with the mineral assemblages of sulfides, implying that the sulfide mineral assemblages reflect local surfacial redox conditions rather than the chemical characteristics of parental fluids.