The Paleo-Pacific Plate stagnated in the mantle transition zone beneath northeast Asia during the Late Mesozoic,resulting in the eastern Asian big mantle wedge(BMW).However,its formation mechanism remains unclear.Here...The Paleo-Pacific Plate stagnated in the mantle transition zone beneath northeast Asia during the Late Mesozoic,resulting in the eastern Asian big mantle wedge(BMW).However,its formation mechanism remains unclear.Here,we analyzed elemental and isotopic compositions of 126-60 Ma intraplate basaltic rocks to map the mantle flow pattern and investigate the implications for the formation of the BMW.These rocks exhibit eastward an increase in Ba/Nb,Ba/La,^(87)Sr/^(86)Sr,and^(208)Pb/^(204)Pb ratios,while a decrease in Nb/Yb,Zr/Yb,Ta/Yb,and Nb/Nb*ratios,indicating mixing between the fertile mantle and the depleted mantle modified by slab material,implying the occurrence of trench-perpendicular mantle flow.The coeval mantle flow and formation of the BMW,the similar directions of mantle flow and Paleo-Pacific Plate subduction,and migration of basin depocenters indicate trench-perpendicular mantle flow was a key factor in the formation of the BMW.Moreover,these basaltic rocks have elevatedδ^(66)Zn values(0.22‰to 0.52‰),indicating recycled carbonates have been added into their mantle source,which increased the mantle flow velocity.Combined with slab roll-back in the Late Mesozoic,it created the essential conditions for mantle flow to promote the formation of the eastern Asian BMW.展开更多
Continental intraplate basalts form by partial melting of the mantle,and can provide important constraints on mantle heterogeneity.However,due to the thick overlying continental lithosphere,the origins of the geochemi...Continental intraplate basalts form by partial melting of the mantle,and can provide important constraints on mantle heterogeneity.However,due to the thick overlying continental lithosphere,the origins of the geochemical characteristics of continental intraplate basalts are controversial.In this study,we examined the geochemistry of Cenozoic basalts in southeast China.These basalts which are divided into four volcanic belts exhibit a DMM-EM2 mixing trend and spatial variations in Pb isotopes from inland(i.e.,thick lithosphere)to coastal(i.e.,thin lithosphere)regions.In contrast to the Pb isotopic variations,there are no spatial variations in Sr-Nd-Hf isotopes.Marked correlations between Pb isotopes and major elements(i.e.,Mg O and Si O_(2))suggest the continental lithospheric lid controlled their petrogenesis.Nonetheless,other factors are needed to explain the variations in Ti/Ti^(*)and Hf/Hf^(*)ratios,and Nd-Hf isotopes of the southeast China basalts.The increasing Pb isotope ratios from the inner to coastal regions are associated with decreases in CaO/Al_(2)O_(3) ratios and increases in FC3MS(FeO^(T)/CaO-3×Mg O/Si O_(2);in wt.%)values,indicating contributions from non-peridotite components in the mantle sources.The similarly depleted Nd-Hf isotopic compositions of the basalts from the three inner belts indicate these basalts have a similar origin,whereas the more enriched isotopic features of the basalts from the outer belt suggest their mantle source contains older recycled oceanic crust.Thus,source(i.e.,lithological)heterogeneity also had a significant role in controlling the geochemistry of these basalts.The DMM-EM2 mixing trend defined by the Pb isotopic compositions of continental intraplate basalts from southeast China was generated by variable degrees of melting of heterogeneous mantle that was controlled by the thickness of the continental lithospheric lid(i.e.,the melting pressure).This caused variable extents of melting of enriched components in the mantle sources of the basalts(i.e.,carbonated peridotite vs.pyroxenite).展开更多
Water content, whether as free or lattice-bound water, is a crucial factor in determining the Earth's internal thermal state and plays a key role in volcanic eruptions, melting phenomena, and mantle convection rat...Water content, whether as free or lattice-bound water, is a crucial factor in determining the Earth's internal thermal state and plays a key role in volcanic eruptions, melting phenomena, and mantle convection rates. As electrical conductivity in the Earth's interior is highly sensitive to water content, it is an important geophysical parameter for understanding the deep Earth water content. Since its launch on May 21, 2023, the MSS-1(Macao Science Satellite-1) mission has operated for nearly one year, with its magnetometer achieving a precision of higher than 0.5 nT after orbital testing and calibration. Orbiting at 450 kilometers with a unique 41-degree inclination, the satellite enables high-density observations across multiple local times, allowing detailed monitoring of low-latitude regions and enhancing data for global conductivity imaging. To better understand the global distribution of water within the Earth's interior, it is crucial to study internal conductivity structure and water content distribution. To this aim, we introduce a method for using MSS-1 data to estamate induced magnetic fields related to magnetospheric currents. We then develop a trans-dimensional Bayesian approach to reveal Earth's internal conductivity, providing probable conductivity structure with an uncertainty analysis. Finally, by integrating known mineral composition, pressure, and temperature distribution within the mantle, we estimate the water content range in the mantle transition zone, concluding that this region may contain the equivalent of up to 3.0 oceans of water, providing compelling evidence that supports the hypothesis of a deep water cycle within the Earth's interior.展开更多
Mineralogical data are presented for the peridotite xenoliths from Miocene(~19 Ma)Qingyuan basalts in the eastern North China Craton(NCC),with the aim of constraining on property of the sub-continental lithospheric ma...Mineralogical data are presented for the peridotite xenoliths from Miocene(~19 Ma)Qingyuan basalts in the eastern North China Craton(NCC),with the aim of constraining on property of the sub-continental lithospheric mantle(SCLM)beneath the northern Tan-Lu fault zone(TLFZ)during the Cenozoic.The Qingyuan peridotites are dominated by spinel lherzolites with moderate-Mg^(#)olivines(89.4 to 91.2),suggesting that the regional SCLM is mainly transitional and fertile.Light rare earth element(LREE)-depleted,slightly depleted and enriched clinopyroxenes(Cpx)are identified in different peridotites.Chemical compositions of the LREE-enriched Cpx and the presence of phlogopite suggest that the Qingyuan SCLM has experienced silicate-related metasomatism.The synthesis of available mineral chemical data of the mantle xenoliths across the NCC confirms the SCLM beneath the NCC is highly heterogeneous in time and space.The Mesozoic–Cenozoic SCLM beneath the TLFZ and neighboring regions are more fertile and thinner than that beneath the region away from the fault zone.The fertile and refractory peridotite xenoliths experienced varying degrees of silicate and carbonatite metasomatism,respectively.The spatial-temporal lithospheric mantle heterogeneity in composition,age and thickness suggest that the trans-lithosphere fault zone played an important role in heterogeneous replacement of refractory cratonic lithospheric mantle.展开更多
Fabrics of five spinel peridotites collected from Baker Rocks in northern Victoria Land,Antarctica,were investigated to elucidate the evolution of the lithospheric mantle surrounding the Transantarctic Mountains.Analy...Fabrics of five spinel peridotites collected from Baker Rocks in northern Victoria Land,Antarctica,were investigated to elucidate the evolution of the lithospheric mantle surrounding the Transantarctic Mountains.Analyses revealed the development of crystallographic preferred orientations(CPOs),a slight decrease in mean grain size and J-index across varying proportions of clinopyroxene,and interlobate to amoeboid textures.These findings indicate that dislocation creep is the dominant deformation mechanism for the analyzed samples.展开更多
BACKGROUND Mantle cell lymphoma(MCL)is an aggressive B-cell non-Hodgkin lymphoma that rarely presents with cutaneous involvement,which typically occurs in advanced disease stages.Primary cutaneous manifestations are p...BACKGROUND Mantle cell lymphoma(MCL)is an aggressive B-cell non-Hodgkin lymphoma that rarely presents with cutaneous involvement,which typically occurs in advanced disease stages.Primary cutaneous manifestations are particularly uncommon and frequently misdiagnosed.We report a diagnostically challenging case of MCL that first appeared as a nodule on the lower leg.CASE SUMMARY An elderly female had a painless red nodule on the front of her right lower leg for six months.Positron emission tomography-computed tomography showed a soft tissue mass at the same site and increased activity in the right groin lymph nodes.Skin and lymph node biopsies,along with immunostaining,confirmed MCL.The patient began combination chemotherapy,resulting in a marked improvement of skin lesions and lymphadenopathy after two weeks.CONCLUSION Cutaneous manifestations,though uncommon,may serve as the initial clinical presentation of MCL.Dermatologists and pathologists should maintain heigh-tened awareness of this diagnostic possibility when evaluating persistent,atypical cutaneous nodules,particularly in elderly patients.Histopathological evaluation with complete immunophenotypic profiling is paramount for accurate diagnosis.展开更多
The Shangla Complex ophiolite represents a relic of the Neo-Tethyan oceanic lithosphere along the Indus Suture Zone(also known as the Main Mantle Thrust)in northern Pakistan.This section,thrust onto the continental ma...The Shangla Complex ophiolite represents a relic of the Neo-Tethyan oceanic lithosphere along the Indus Suture Zone(also known as the Main Mantle Thrust)in northern Pakistan.This section,thrust onto the continental margin between the Indian and Karakoram(Asian)plates,is predominantly composed of depleted harzburgites,dunites and chromitites.In this study,we conducted a thorough analysis of mineralogy,whole-rock geochemistry(major oxides,trace elements,PGE),and integrated Re-Os isotopic data from mantle-derived peridotites to understand their petrogenesis and melt evolution.These peridotites exhibit a depleted nature,characterized by a low modal composition of clinopyroxene,a wide forsterite content range in olivine(86.5 to 95.2),and a large variation in Cr#values(25.1–91.4).Their diverse whole-rock geochemistry further suggests varying degrees of partial melting.The Cpx-harzburgites show high average Al_(2)O_(3)(1.83 wt.%),CaO(2.27 wt.%),ΣREE(12.9 ppb),and^(187)Os/^(188)Os values between 0.13095 and 0.12571.On the other hand,the depleted harzburgites and dunites exhibit lower average Al_(2)O_(3)(0.57 wt.%and 0.14 wt.%,respectively),CaO concentration(0.59 wt.%and 0.21 wt.%,respectively),and∑REE concentrations,measured at 12.7 ppb and 8.9 ppb,respectively.The^(187)Os/^(188)Os ratios in the depleted harzburgites and dunites range from 0.12643 to 0.11777,indicating they are less radiogenic compared to the Cpx-harzburgites.The spoon-shaped rare earth elements(REE)patterns suggest that the Cpx-harzburgites underwent low degrees of partial melting(∼10%–15%),whereas the depleted harzburgites and dunites indicate somewhat higher degrees of partial melting(additional melting of the Cpx-harzburgites).The PGE abundances in these depleted harzburgites and dunites are linked to the partial melting of Cpx-harzburgites,resulting in a boninitic-like melt.Their low degree of melting and melt extraction suggests that Cpx-harzburgites initially formed at a mid-ocean ridge(MOR)spreading center or a distal fore-arc basin.In contrast,the depleted harzburgites and dunites were formed during a second phase of melting,followed by refertilization,closely associated with a supra-subduction zone(SSZ)setting.The Re-Os isotopic systematics of the Shangla Complex peridotites reveal model age clusters of ca.250 Ma and ca.450 Ma,potentially corresponding to significant tectonic events in the geodynamic evolution of the Neo-Tethyan,Rheic,and Proto-Tethyan oceans.展开更多
This study selects geochemical data of basalts from different seamounts in the Mid-Pacific Mountains province and conducts analyses of major and trace elements as well as Sr-Nd-Pb isotopes to explore the tectonic evol...This study selects geochemical data of basalts from different seamounts in the Mid-Pacific Mountains province and conducts analyses of major and trace elements as well as Sr-Nd-Pb isotopes to explore the tectonic evolution,petrogenesis,and mantle-source magama characteristics of the Mid-Pacific Mountains.The basalts from the Mid-Pacific Mountains are predominantly alkali basalts,rich in alkalies,and changing in potassium.They exhibit geochemical features of ocean island basalts(OIB),with distinct fractionation between light and heavy rare-earth elements and a pronounced Ce negative anomaly(δ_(Ce)=0.16–1.10,average 0.84),along with enrichment in large ion lithophile elements(LILEs).The Mid-Pacific Mountains are intraplate ocean island basalts formed by mantle plume(hotspot)activity,originating mainly from an enriched mantle magma source region,and most of them have undergone low degree of partial melting and a certain degree of crystalline differentiation,with negligible contamination from oceanic crust materials.The Mid-Pacific Mountains exhibit ratios of^(87)Sr/^(86)Sr(i)(0.702733–0.704313,average 0.703452)and^(143)Nd/^(144)Nd(i)(0.512698–0.512996,average 0.512846)which are close to the HIMU mantle endmember,and ratios of 206Pb/204Pb(18.953–19.803),^(207)Pb/^(204)Pb(15.54–15.62)and^(208)Pb/^(204)Pb(38.813–39.514)which are close to the EMII mantle end-member.Combined with the isotopic geochemical characteristics in the West Pacific Seamounts province,the basalts from the Mid-Pacific Mountains were considered to represent a certain proportion of mixing mantle end-members between the HIMU and EMII,possibly formed by the mixing of the HIMU superplume in the South Pacific hotspot region with the EMII secondary mantle plume in the transition zone during their ascent.展开更多
Marine carbonates,the major carrier of carbon upon the upper crust,can be subducted into the Earth’s interior along with oceanic crust,and then returned to the surface through magmatism,which constitute the deep carb...Marine carbonates,the major carrier of carbon upon the upper crust,can be subducted into the Earth’s interior along with oceanic crust,and then returned to the surface through magmatism,which constitute the deep carbon cycle.This process plays an important role in modulating the CO_(2) concentrations in the atmosphere over geologic time,and thus the forming of the habitable earth.Therefore,identifying recycled marine carbonates in the mantle is critical to well understand the global deep carbon cycle.Calcium is one of the major constituent cations in marine carbonates and its isotopes may be a potential tracer for recycled marine carbonates in the mantle.To further evaluate the capability and challenges of Ca isotopes as such a geochemical tracer,we reviewed the Ca isotopic compositions in important reservoirs and the behavior of Ca isotopes during high-temperature geological processes that are related to the deep carbon cycle,including plate subduction,mantle metasomatism,mantle partial melting,magma differentiation,etc.Available studies show that carbonate-rich marine sediments have significantly lowerδ^(44/40) Ca than the Earth mantle,and metasomatism by such recycled materials can cause lighter Ca isotopic compositions in deep mantle-derived rocks than those of the depleted mantle and mid ocean ridge basalts.However,the Ca isotopic fractionation during partial melting of mantle peridotites is small(~0.10‰)and the Ca isotopic fractionation during plate subduction and intermediate-mafic magma evolution is indistinguishable.These investigations suggest that Ca isotopes have great advances in tracing such recycled materials in the mantle.However,other processes(such as the influence by partial melts of eclogites)may induce similar effects on mantle-derived rocks as subducted marine carbonates but still remains debated,and thus further investigations are strongly needed in the future.展开更多
The Longshan orogenic belt is located in the southwestern margin of Ordos Basin at the junction zone between the Western Qinling and Northern Qilian orogenic belt.Voluminous Early Paleozoic magmatism in this area is o...The Longshan orogenic belt is located in the southwestern margin of Ordos Basin at the junction zone between the Western Qinling and Northern Qilian orogenic belt.Voluminous Early Paleozoic magmatism in this area is of key significance for determining the Early Paleozoic tectonic evolution and deep crust-mantle structure.Previous studies mainly focused on the Paleozoic granites;the coeval mafic rocks in this area are still poorly understood.A set of Late Silurian intraplate tholeiitic basalts has been discovered in Longshan area,providing key evidence for the mantle source and deep geodynamic background in this area.The Late Silurian Angou basalt has similar geochemical features as intraplate tholeiitic basalt,with high Na_(2)O/K_(2)O ratios(5.22-8.25),enriched in large ion lithophile elements and LREE.In combination with their relatively evolved Sr-Nd isotopic composition[^(87)Sr/^(86)Sr(i)=0.7128-0.7140;ε_(Nd)(t)=-5.55 to-3.40],it is suggested that it originated from decompression melting of metasomatized enriched mantle in extensional setting.These results indicate that the mantle source in the junction zone of the West Qinling-North Qilian orogenic belt evolved from depleted to enriched with the continuation of Proto-Tethys subduction from the Cambrian to the Silurian.These results are of great significance to understanding the genesis of contemporaneous granite and the crust-mantle interaction in the junction zone between the Western Qinling and Northern Qilian orogenic belt.展开更多
Mantle plumes and surface erosion and sediment deposition affect the modes of continental lithospheric rupturing in extensional tectonic settings,modulating the evolution of rifting margins.However,their relative cont...Mantle plumes and surface erosion and sediment deposition affect the modes of continental lithospheric rupturing in extensional tectonic settings,modulating the evolution of rifting margins.However,their relative contributions to the overall evolution of rifting margins and possible roles in the formation of microcontinent are still elusive.Here,we use coupled geodynamic and surface processes numerical modeling to assess the extent to which surface processes may determine the formation of microcontinent during lithospheric stretching in presence or absence of a mantle plume underneath.Our modeling results indicate that fast extension rates and hillslope(i.e.,diffusion)erosion promote ridge jump events and therefore the formation of microcontinents.On the contrary,efficient fluvial erosion and far-reaching sediment transport(i.e.,stream power erosion)inhibits ridge jump events and the formation of microcontinents.The ridge jump event and overall evolution in our numerical models is consistent with the shift from the Mascarene Ridge to the Carlsberg Ridge that determined the formation of the Seychelles microcontinent.We therefore speculate that hillslope erosion,rather than fluvial erosion,was predominant during the formation of the Seychelles,a possible indication of overall dry local climate conditions.展开更多
BACKGROUND In addition to nodal lesions,over 30%of mantle cell lymphomas(MCLs)also have gastrointestinal involvement,characteristically presenting as multiple lymphomatous polyposis(MLP),which rarely involve the esoph...BACKGROUND In addition to nodal lesions,over 30%of mantle cell lymphomas(MCLs)also have gastrointestinal involvement,characteristically presenting as multiple lymphomatous polyposis(MLP),which rarely involve the esophagus.Most related papers have been case reports,and no comprehensive studies have been conducted;thus,the actual clinical situation has remained unknown for a long time.AIM To elucidate the actual clinical situation of esophageal involvement of MCL presenting with MLP,including its prognosis.METHODS From January 2001 to December 2021,among MCL patients whose gastrointestinal lesions were histopathologically confirmed by endoscopic biopsy at our center,6 patients with MLP in the esophagus were selected.We retro-spectively examined the clinical features of these patients,including their prognosis.RESULTS In all patients,multiple lesions were present in the gastrointestinal tract other than the esophagus and in the lymph nodes throughout the body,and most patients also had lesions involving the bone marrow or spleen.Most of the treatments include chemotherapy,with a 50%survival period of less than 2 years and a 5-year survival rate of approximately 30%,indicating a poor prognosis.CONCLUSION Patients with esophageal involvement of the MCL who presented with MLP had a large tumor burden and poor survival.展开更多
Objective:Our previous studies have indicated potentially higher proliferative activity of tumor cells in Chinese patients with mantle-cell lymphoma(MCL)than those in Western.Given the success and tolerability of R-DA...Objective:Our previous studies have indicated potentially higher proliferative activity of tumor cells in Chinese patients with mantle-cell lymphoma(MCL)than those in Western.Given the success and tolerability of R-DA-EDOCH immunochemotherapy in treating aggressive B-cell lymphomas,we designed a prospective,phase 3 trial to explore the efficacy and safety of alternating R-DA-EDOCH/R-DHAP induction therapy for young patients with newly diagnosed MCL.The primary endpoint was the complete remission rate(CRR)at the end of induction(EOI).Methods:A total of 55 patients were enrolled.The CRR at the EOI was 89.1%[95%confidence interval(CI)78%±96%],and the overall response rate was 98.1%(95%CI 90%±100%).Most patients with bone marrow involvement quickly attained minimal residual disease(MRD)negative status,with a 95.7%rate at the EOI.Results:The 3-year progression-free survival(PFS)and overall survival rates were 66.3%and 83.2%,respectively.No patients discontinued treatment because of adverse events.Univariate analysis identified pathologic morphology and TP53 mutations as risk factors for PFS.However,high tumor proliferative activity and certain cytogenetic abnormalities showed no significant adverse prognostic significance.Conclusions:Intensive therapy based on a high cytarabine dose and continuously administered EDOCH achieved a high MRDnegative rate and provides an optional induction choice for young patients with MCL with high-risk factors.展开更多
This retrospective case study investigates the clinical presentation of a 53-year-old female who underwent mantle field radiotherapy roughly 26 years ago. This patient presents with diffuse muscle atrophy and weakness...This retrospective case study investigates the clinical presentation of a 53-year-old female who underwent mantle field radiotherapy roughly 26 years ago. This patient presents with diffuse muscle atrophy and weakness in the cervical musculature, as well as sensory deficits in the upper extremities. We sought to compare our patient’s symptoms with other patients who had been formally diagnosed with Dropped Head Syndrome (DHS) by reviewing the existing literature. We found that the clinical presentation under investigation was consistent with other patients who had received radiotherapy for Hodgkins’s disease and were then diagnosed with DHS. Electromyography (EMG), nerve conduction studies, and a cervical MRI were unable to identify a separate neurological cause for the symptoms, but the MRI did confirm the presence of diffuse muscle atrophy in the cervical musculature. After reviewing the existing literature and imaging results, we compared our patient’s symptoms to those that define DHS, and both the time of onset, presenting symptoms, and progressing course are consistent with a diagnosis of Dropped Head Syndrome.展开更多
The North China Craton(NCC)experienced significant lithospheric thinning of over 100 km during the Mesozoic,accompanied by extensive magmatic activity and extensional tectonics.However,the timing and mechanism of this...The North China Craton(NCC)experienced significant lithospheric thinning of over 100 km during the Mesozoic,accompanied by extensive magmatic activity and extensional tectonics.However,the timing and mechanism of this thinning remain the subjects of debate.This study presents zircon U-Pb ages,Hf isotopic data and whole-rock elemental and Sr-Nd isotopic compositions of the Guanshui monzonites and diorites in the eastern NCC.Zircon U-Pb dating reveals that both rock types formed at ca.130 Ma.The monzonites,characterized by high Mg^(#)(50.9-57.9),low Nb/U ratios(2.53-3.89)and depleted isotopic compositions,suggest derivation from asthenospheric mantle modified by slab-derived fluids.The diorites,distinguished by low SiO_(2)(49.5-50.8),high Mg^(#)(66.7-68.5)and an EM2-type enriched mantle isotopic signature,point to a lithospheric mantle source modified by subducted sediment melts.The coexistence of monzonites and diorites suggests a transition in magma source from lithospheric to asthenospheric mantle,implying that lithospheric thinning may have commenced around 130 Ma.The destruction of the NCC was likely driven by localized,small-scale drip-style detachment processes,rather than wholesale lithospheric removal.展开更多
Mafic rocks generated from subduction settings have recorded valuable source information about the mantle source.In this study,we present a comprehensive analysis of zircon U–Pb dating,whole-rock major and trace elem...Mafic rocks generated from subduction settings have recorded valuable source information about the mantle source.In this study,we present a comprehensive analysis of zircon U–Pb dating,whole-rock major and trace elements,and Sr–Nd isotopic data for the mafic gabbro located in the Yumen area,on the western part of the Yangtze Block,South China,aiming to constrain the processes of mantle metaso-matism within subduction settings.U–Pb dating results for zircon yield crystallization ages of 800 Ma for type 1 mafic gabbro and 753–734 Ma for type 2 mafic gabbro.Type 1 mafic gabbro exhibits higher SiO_(2)(44.13%–48.93%)and Al_(2)O_(3)content but lower total Fe2O3 and MgO content than type 2 gabbro(SiO_(2):41.02%–43.28%).These gabbros dis-play a high-Mg^(#)signature(52.50–62.81 for type 1,50.89–57.04 for type 2),while they are enriched in significant large-ion lithophile elements(LILEs:Rb,Ba,Sr,K)and depleted in high-field-strength elements(HFSEs:Zr,Hf,Nd,Ta,Ti),which indicates an arc-like element signature.The positive whole-rockεNd(t)values(type 1:3.5–4.4,type 2:5.6–6.3)combined with a narrow range of(^(87)Sr/^(86)Sr)_(i)(type 1:0.7035–0.7043,type 2:0.7035–0.7036)of both gabbro types suggest a depleted lithospheric mantle origin.There-fore,these mafic rocks may derive from a metasomatized spinel lherzolite mantle source(with amphibole)due to the interactions of the deep mantle source and subductionfluid materials.We propose that the long-term metasomatism recorded by mafic gabbro in this study supports the fact that the subduction during the Neoproterozoic contributed to the formation of a metasomatized mantle source in the Yumen area,western Yangtze Block,South China.展开更多
The post-collisional Cenozoic basic volcanic rocks in NE Turkey show temporal variations in whole-rock lithophile element and highly siderophile element(HSE)systematics that are mainly associated with the nature of su...The post-collisional Cenozoic basic volcanic rocks in NE Turkey show temporal variations in whole-rock lithophile element and highly siderophile element(HSE)systematics that are mainly associated with the nature of sub-continental lithospheric mantle(SCLM)sources and parental melt generation.So far,the traditional whole-rock lithophile geochemical data of these basic volcanic rocks have provided important constraints on the nature of SCLM sources.Integrated lithophile element and HSE geochemical data of these basic volcanic rocks also reveal the heterogeneity of the SCLM source,which is principally related to variable metasomatism resulting from previous subduction(s)and post-collisional mantle-crust interactions in an extensional setting.Lithophile element geochemical features suggest that the parental magmas have derived from metasomatized spinel-to garnet-bearing SCLM sources for Eocene and Miocene basic volcanic rocks with subduction signatures whereas originated from spinel-to garnet-bearing SCLM sources for Mio-Pliocene and Plio-Quaternary basaltic volcanic rocks without the subduction signature.Lithophile element and HSE geo-chemistry also reveal that Eocene and Miocene basic vol-canic rocks were affected by more pronounced crustal contamination than the basaltic volcanic rocks of Mio-Pliocene and Quaternary.Furthermore,the integrated lithophile element and HSE compositions of these basic volcanic rocks,together with the regional asymmetric lithospheric delamination model,reveal that the compositional variation(especially due to metasomatism)was significant temporally in the heterogeneity of the SCLM sources from which parental magmas formed during the Cenozoic era.展开更多
Magmatic periodicity is recognized in continental arcs worldwide,but the mechanism responsible for punctuated arc magmatism is controversial.Continental arcs in the Trans-Himalayan orogenic system display episodic mag...Magmatic periodicity is recognized in continental arcs worldwide,but the mechanism responsible for punctuated arc magmatism is controversial.Continental arcs in the Trans-Himalayan orogenic system display episodic magmatism and the most voluminous flare-up in this system was in early Eocene during the transition from subduction to collision.The close association of the flare-up with collision is intriguing.Our study employs zircon Lu-Hf and bulk rock Sr-Nd isotopes,along with mineral geochemistry,to track the melt sources of the Nymo intrusive complex and the role of mantle magma during the early Eocene flare-up of the Gangdese arc,Xizang.The Nymo intrusive complex is composed of gabbronorite,diorite,quartz diorite,and granodiorite which define an arc-related calc-alkaline suite.Zircon U-Pb ages reveal that the complex was emplaced between~50–47 Ma.Zircon Hf isotopes yieldεHf(t)values of 8.2–13.1,while whole-rock Sr and Nd isotopes yieldεNd(t)values of 2.7–6.5 indicative of magmatism dominated by melting of a juvenile mantle source with only minor crustal assimilation(~15%–25%)as indicated by assimilation and fractional crystallization modeling.Together with published data,the early Eocene magmatic flare-up was likely triggered by slab breakoff of subducted oceanic lithosphere at depths shallower than the overriding plate.The early Eocene magmatic flare-up may have contributed to crustal thickening of the Gangdese arc.This study provides important insights into the magmatic flare-up and its significant role in the generation of large batholiths during the transition from subduction to collision.展开更多
Using the secondary spinel standard, the authors have precisely measured theFe^(3+)/SIGMA Fe values of spinels in mantle xenoliths from Cenozoic basalts in eastern China, andestimated the oxygen fugacities recorded by...Using the secondary spinel standard, the authors have precisely measured theFe^(3+)/SIGMA Fe values of spinels in mantle xenoliths from Cenozoic basalts in eastern China, andestimated the oxygen fugacities recorded by 63 mantle xenoliths through olivine-orthopyroxene-spineloxygen barometry. The results indicate that the oxygen fugacities of the lithospheric mantle ineastern China are higher in the south than in the north. Among them, the oxygen fugacity of theNorth China craton lithospheric mantle is the lowest, similar to that of the oceanic mantle, whilethat of Northeast and South China are the same as that of the global continental mantle. Thevariations of mantle redox state in eastern China are mainly controlled by the C-O-H fluids derivedfrom the asthenospheric mantle. According to the mantle oxidation state, it can be concluded thatthe C-O-H fluids in the lithospheric mantle of eastern China consist mainly of CO_2 and minor H_2O,but CH_4-rich fluids should come from the asthenosphere where the oxidation state is lower.展开更多
Hydrous Cr-bearing uvarovite garnets are rare in natural occurrences and belong to the ugrandite series and exist in binary solid solutions with grossular and andradite garnets. Here, we report the occurrence of hydro...Hydrous Cr-bearing uvarovite garnets are rare in natural occurrences and belong to the ugrandite series and exist in binary solid solutions with grossular and andradite garnets. Here, we report the occurrence of hydrous uvarovite garnet having Cr_(2)O_(3) upto 19.66 wt% and CaO of 32.12–35.14 wt% in the serpentinized mantle peridotites of Naga Hills Ophiolite(NHO), India. They occur in association with low-Cr diopsides. They are enriched in LILE(Ba, Sr), LREEs, with fractionating LREE-MREE [avg.(La/Sm)_(N) = 2.16] with flat MREE/HREE patterns [avg.(Sm/Yb)_(N) = 0.95]. Raman spectra indicate the presence of hydroxyl(OH^(–)) peaks from 3500 to 3700 cm^(-1). Relative abundances in fluid mobile elements and their close association with clinopyroxenes are suggestive of the formation of uvarovite garnets through low temperature metasomatic alteration of low-Cr diopsides by hydrothermal slab fluids. The high LREE concentration and absence of Eu anomaly in the garnet further attest to alkaline nature of the transporting slab dehydrated fluid rather the involvement of low-p H solution. The chemical characteristics of the hydroxyl bearing uvarovite hosted by the mantle peridotite of NHO deviate from the classical features of uvarovite garnet, and their origin is attributed to the fluid-induced metasomatism of the sub arc mantle wedge in a suprasubduction zone regime.展开更多
基金financially supported by the National Key R&D Program of China(No.2022YFF0801002)the National Natural Science Foundation of China(No.42372065)the Natural Science Foundation of Jilin Province(No.20220101178JC)。
文摘The Paleo-Pacific Plate stagnated in the mantle transition zone beneath northeast Asia during the Late Mesozoic,resulting in the eastern Asian big mantle wedge(BMW).However,its formation mechanism remains unclear.Here,we analyzed elemental and isotopic compositions of 126-60 Ma intraplate basaltic rocks to map the mantle flow pattern and investigate the implications for the formation of the BMW.These rocks exhibit eastward an increase in Ba/Nb,Ba/La,^(87)Sr/^(86)Sr,and^(208)Pb/^(204)Pb ratios,while a decrease in Nb/Yb,Zr/Yb,Ta/Yb,and Nb/Nb*ratios,indicating mixing between the fertile mantle and the depleted mantle modified by slab material,implying the occurrence of trench-perpendicular mantle flow.The coeval mantle flow and formation of the BMW,the similar directions of mantle flow and Paleo-Pacific Plate subduction,and migration of basin depocenters indicate trench-perpendicular mantle flow was a key factor in the formation of the BMW.Moreover,these basaltic rocks have elevatedδ^(66)Zn values(0.22‰to 0.52‰),indicating recycled carbonates have been added into their mantle source,which increased the mantle flow velocity.Combined with slab roll-back in the Late Mesozoic,it created the essential conditions for mantle flow to promote the formation of the eastern Asian BMW.
基金supported by the National Natural Science Foundation of China(No.41906051)the National Key R&D Program of China(No.2018YFE0202402)+1 种基金sponsored by the Fundamental Research Funds for the Central Universities(Tongji University)(No.22120210525)Shanghai Pilot Program for Basic Research。
文摘Continental intraplate basalts form by partial melting of the mantle,and can provide important constraints on mantle heterogeneity.However,due to the thick overlying continental lithosphere,the origins of the geochemical characteristics of continental intraplate basalts are controversial.In this study,we examined the geochemistry of Cenozoic basalts in southeast China.These basalts which are divided into four volcanic belts exhibit a DMM-EM2 mixing trend and spatial variations in Pb isotopes from inland(i.e.,thick lithosphere)to coastal(i.e.,thin lithosphere)regions.In contrast to the Pb isotopic variations,there are no spatial variations in Sr-Nd-Hf isotopes.Marked correlations between Pb isotopes and major elements(i.e.,Mg O and Si O_(2))suggest the continental lithospheric lid controlled their petrogenesis.Nonetheless,other factors are needed to explain the variations in Ti/Ti^(*)and Hf/Hf^(*)ratios,and Nd-Hf isotopes of the southeast China basalts.The increasing Pb isotope ratios from the inner to coastal regions are associated with decreases in CaO/Al_(2)O_(3) ratios and increases in FC3MS(FeO^(T)/CaO-3×Mg O/Si O_(2);in wt.%)values,indicating contributions from non-peridotite components in the mantle sources.The similarly depleted Nd-Hf isotopic compositions of the basalts from the three inner belts indicate these basalts have a similar origin,whereas the more enriched isotopic features of the basalts from the outer belt suggest their mantle source contains older recycled oceanic crust.Thus,source(i.e.,lithological)heterogeneity also had a significant role in controlling the geochemistry of these basalts.The DMM-EM2 mixing trend defined by the Pb isotopic compositions of continental intraplate basalts from southeast China was generated by variable degrees of melting of heterogeneous mantle that was controlled by the thickness of the continental lithospheric lid(i.e.,the melting pressure).This caused variable extents of melting of enriched components in the mantle sources of the basalts(i.e.,carbonated peridotite vs.pyroxenite).
基金financially supported by the National Natural Science Foundation of China(42250102,42250101)the Macao Foundation.
文摘Water content, whether as free or lattice-bound water, is a crucial factor in determining the Earth's internal thermal state and plays a key role in volcanic eruptions, melting phenomena, and mantle convection rates. As electrical conductivity in the Earth's interior is highly sensitive to water content, it is an important geophysical parameter for understanding the deep Earth water content. Since its launch on May 21, 2023, the MSS-1(Macao Science Satellite-1) mission has operated for nearly one year, with its magnetometer achieving a precision of higher than 0.5 nT after orbital testing and calibration. Orbiting at 450 kilometers with a unique 41-degree inclination, the satellite enables high-density observations across multiple local times, allowing detailed monitoring of low-latitude regions and enhancing data for global conductivity imaging. To better understand the global distribution of water within the Earth's interior, it is crucial to study internal conductivity structure and water content distribution. To this aim, we introduce a method for using MSS-1 data to estamate induced magnetic fields related to magnetospheric currents. We then develop a trans-dimensional Bayesian approach to reveal Earth's internal conductivity, providing probable conductivity structure with an uncertainty analysis. Finally, by integrating known mineral composition, pressure, and temperature distribution within the mantle, we estimate the water content range in the mantle transition zone, concluding that this region may contain the equivalent of up to 3.0 oceans of water, providing compelling evidence that supports the hypothesis of a deep water cycle within the Earth's interior.
基金supported by funds from the Ministry of Science and Technology of the People's Republic of China(No.2019YFA0708603)NSFC(Nos.41973050,42288201,41930215)the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(No.GML2019ZD0202)。
文摘Mineralogical data are presented for the peridotite xenoliths from Miocene(~19 Ma)Qingyuan basalts in the eastern North China Craton(NCC),with the aim of constraining on property of the sub-continental lithospheric mantle(SCLM)beneath the northern Tan-Lu fault zone(TLFZ)during the Cenozoic.The Qingyuan peridotites are dominated by spinel lherzolites with moderate-Mg^(#)olivines(89.4 to 91.2),suggesting that the regional SCLM is mainly transitional and fertile.Light rare earth element(LREE)-depleted,slightly depleted and enriched clinopyroxenes(Cpx)are identified in different peridotites.Chemical compositions of the LREE-enriched Cpx and the presence of phlogopite suggest that the Qingyuan SCLM has experienced silicate-related metasomatism.The synthesis of available mineral chemical data of the mantle xenoliths across the NCC confirms the SCLM beneath the NCC is highly heterogeneous in time and space.The Mesozoic–Cenozoic SCLM beneath the TLFZ and neighboring regions are more fertile and thinner than that beneath the region away from the fault zone.The fertile and refractory peridotite xenoliths experienced varying degrees of silicate and carbonatite metasomatism,respectively.The spatial-temporal lithospheric mantle heterogeneity in composition,age and thickness suggest that the trans-lithosphere fault zone played an important role in heterogeneous replacement of refractory cratonic lithospheric mantle.
基金supported by the Korea Polar Research Institute project PE24050.
文摘Fabrics of five spinel peridotites collected from Baker Rocks in northern Victoria Land,Antarctica,were investigated to elucidate the evolution of the lithospheric mantle surrounding the Transantarctic Mountains.Analyses revealed the development of crystallographic preferred orientations(CPOs),a slight decrease in mean grain size and J-index across varying proportions of clinopyroxene,and interlobate to amoeboid textures.These findings indicate that dislocation creep is the dominant deformation mechanism for the analyzed samples.
基金Supported by the Department of Science and Technology of Sichuan Province,No.2023NSFSC0724.
文摘BACKGROUND Mantle cell lymphoma(MCL)is an aggressive B-cell non-Hodgkin lymphoma that rarely presents with cutaneous involvement,which typically occurs in advanced disease stages.Primary cutaneous manifestations are particularly uncommon and frequently misdiagnosed.We report a diagnostically challenging case of MCL that first appeared as a nodule on the lower leg.CASE SUMMARY An elderly female had a painless red nodule on the front of her right lower leg for six months.Positron emission tomography-computed tomography showed a soft tissue mass at the same site and increased activity in the right groin lymph nodes.Skin and lymph node biopsies,along with immunostaining,confirmed MCL.The patient began combination chemotherapy,resulting in a marked improvement of skin lesions and lymphadenopathy after two weeks.CONCLUSION Cutaneous manifestations,though uncommon,may serve as the initial clinical presentation of MCL.Dermatologists and pathologists should maintain heigh-tened awareness of this diagnostic possibility when evaluating persistent,atypical cutaneous nodules,particularly in elderly patients.Histopathological evaluation with complete immunophenotypic profiling is paramount for accurate diagnosis.
基金supported by a grant from the Science and Technology Innovation Program of Hunan Province(Grant No.2021RC4055)Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring,during the Postdoctoral research of the first author(Zaheen Ullah,Assistant Professor,University of Swat,Pakistan)at the Central South University,Changsha,China.
文摘The Shangla Complex ophiolite represents a relic of the Neo-Tethyan oceanic lithosphere along the Indus Suture Zone(also known as the Main Mantle Thrust)in northern Pakistan.This section,thrust onto the continental margin between the Indian and Karakoram(Asian)plates,is predominantly composed of depleted harzburgites,dunites and chromitites.In this study,we conducted a thorough analysis of mineralogy,whole-rock geochemistry(major oxides,trace elements,PGE),and integrated Re-Os isotopic data from mantle-derived peridotites to understand their petrogenesis and melt evolution.These peridotites exhibit a depleted nature,characterized by a low modal composition of clinopyroxene,a wide forsterite content range in olivine(86.5 to 95.2),and a large variation in Cr#values(25.1–91.4).Their diverse whole-rock geochemistry further suggests varying degrees of partial melting.The Cpx-harzburgites show high average Al_(2)O_(3)(1.83 wt.%),CaO(2.27 wt.%),ΣREE(12.9 ppb),and^(187)Os/^(188)Os values between 0.13095 and 0.12571.On the other hand,the depleted harzburgites and dunites exhibit lower average Al_(2)O_(3)(0.57 wt.%and 0.14 wt.%,respectively),CaO concentration(0.59 wt.%and 0.21 wt.%,respectively),and∑REE concentrations,measured at 12.7 ppb and 8.9 ppb,respectively.The^(187)Os/^(188)Os ratios in the depleted harzburgites and dunites range from 0.12643 to 0.11777,indicating they are less radiogenic compared to the Cpx-harzburgites.The spoon-shaped rare earth elements(REE)patterns suggest that the Cpx-harzburgites underwent low degrees of partial melting(∼10%–15%),whereas the depleted harzburgites and dunites indicate somewhat higher degrees of partial melting(additional melting of the Cpx-harzburgites).The PGE abundances in these depleted harzburgites and dunites are linked to the partial melting of Cpx-harzburgites,resulting in a boninitic-like melt.Their low degree of melting and melt extraction suggests that Cpx-harzburgites initially formed at a mid-ocean ridge(MOR)spreading center or a distal fore-arc basin.In contrast,the depleted harzburgites and dunites were formed during a second phase of melting,followed by refertilization,closely associated with a supra-subduction zone(SSZ)setting.The Re-Os isotopic systematics of the Shangla Complex peridotites reveal model age clusters of ca.250 Ma and ca.450 Ma,potentially corresponding to significant tectonic events in the geodynamic evolution of the Neo-Tethyan,Rheic,and Proto-Tethyan oceans.
基金Supported by the National Natural Science Foundation of China(No.U2244222).
文摘This study selects geochemical data of basalts from different seamounts in the Mid-Pacific Mountains province and conducts analyses of major and trace elements as well as Sr-Nd-Pb isotopes to explore the tectonic evolution,petrogenesis,and mantle-source magama characteristics of the Mid-Pacific Mountains.The basalts from the Mid-Pacific Mountains are predominantly alkali basalts,rich in alkalies,and changing in potassium.They exhibit geochemical features of ocean island basalts(OIB),with distinct fractionation between light and heavy rare-earth elements and a pronounced Ce negative anomaly(δ_(Ce)=0.16–1.10,average 0.84),along with enrichment in large ion lithophile elements(LILEs).The Mid-Pacific Mountains are intraplate ocean island basalts formed by mantle plume(hotspot)activity,originating mainly from an enriched mantle magma source region,and most of them have undergone low degree of partial melting and a certain degree of crystalline differentiation,with negligible contamination from oceanic crust materials.The Mid-Pacific Mountains exhibit ratios of^(87)Sr/^(86)Sr(i)(0.702733–0.704313,average 0.703452)and^(143)Nd/^(144)Nd(i)(0.512698–0.512996,average 0.512846)which are close to the HIMU mantle endmember,and ratios of 206Pb/204Pb(18.953–19.803),^(207)Pb/^(204)Pb(15.54–15.62)and^(208)Pb/^(204)Pb(38.813–39.514)which are close to the EMII mantle end-member.Combined with the isotopic geochemical characteristics in the West Pacific Seamounts province,the basalts from the Mid-Pacific Mountains were considered to represent a certain proportion of mixing mantle end-members between the HIMU and EMII,possibly formed by the mixing of the HIMU superplume in the South Pacific hotspot region with the EMII secondary mantle plume in the transition zone during their ascent.
基金Supported by the National Natural Science Foundation of China(Nos.42322302,42373048)the Youth Innovation Promotion Association,Chinese Academy of Sciences(No.2022207)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB42020303)the Laoshan Laboratory(No.LSKJ202204100)。
文摘Marine carbonates,the major carrier of carbon upon the upper crust,can be subducted into the Earth’s interior along with oceanic crust,and then returned to the surface through magmatism,which constitute the deep carbon cycle.This process plays an important role in modulating the CO_(2) concentrations in the atmosphere over geologic time,and thus the forming of the habitable earth.Therefore,identifying recycled marine carbonates in the mantle is critical to well understand the global deep carbon cycle.Calcium is one of the major constituent cations in marine carbonates and its isotopes may be a potential tracer for recycled marine carbonates in the mantle.To further evaluate the capability and challenges of Ca isotopes as such a geochemical tracer,we reviewed the Ca isotopic compositions in important reservoirs and the behavior of Ca isotopes during high-temperature geological processes that are related to the deep carbon cycle,including plate subduction,mantle metasomatism,mantle partial melting,magma differentiation,etc.Available studies show that carbonate-rich marine sediments have significantly lowerδ^(44/40) Ca than the Earth mantle,and metasomatism by such recycled materials can cause lighter Ca isotopic compositions in deep mantle-derived rocks than those of the depleted mantle and mid ocean ridge basalts.However,the Ca isotopic fractionation during partial melting of mantle peridotites is small(~0.10‰)and the Ca isotopic fractionation during plate subduction and intermediate-mafic magma evolution is indistinguishable.These investigations suggest that Ca isotopes have great advances in tracing such recycled materials in the mantle.However,other processes(such as the influence by partial melts of eclogites)may induce similar effects on mantle-derived rocks as subducted marine carbonates but still remains debated,and thus further investigations are strongly needed in the future.
基金supported by the National Natural Science Foundation of China(42172010,42372071,41102037)。
文摘The Longshan orogenic belt is located in the southwestern margin of Ordos Basin at the junction zone between the Western Qinling and Northern Qilian orogenic belt.Voluminous Early Paleozoic magmatism in this area is of key significance for determining the Early Paleozoic tectonic evolution and deep crust-mantle structure.Previous studies mainly focused on the Paleozoic granites;the coeval mafic rocks in this area are still poorly understood.A set of Late Silurian intraplate tholeiitic basalts has been discovered in Longshan area,providing key evidence for the mantle source and deep geodynamic background in this area.The Late Silurian Angou basalt has similar geochemical features as intraplate tholeiitic basalt,with high Na_(2)O/K_(2)O ratios(5.22-8.25),enriched in large ion lithophile elements and LREE.In combination with their relatively evolved Sr-Nd isotopic composition[^(87)Sr/^(86)Sr(i)=0.7128-0.7140;ε_(Nd)(t)=-5.55 to-3.40],it is suggested that it originated from decompression melting of metasomatized enriched mantle in extensional setting.These results indicate that the mantle source in the junction zone of the West Qinling-North Qilian orogenic belt evolved from depleted to enriched with the continuation of Proto-Tethys subduction from the Cambrian to the Silurian.These results are of great significance to understanding the genesis of contemporaneous granite and the crust-mantle interaction in the junction zone between the Western Qinling and Northern Qilian orogenic belt.
基金financially supported by the National Science Foundation of China(No.41920104010)the China Postdoctoral Science Foundation(No.2024M762767)+3 种基金the Fundamental Research Funds for the Central University,CHD(No.300102264104)by the Postdoctoral Fellowship Program of CPSF(No.GZC20241444)supported by Fondazione Cariplo and Fondazione CDP(No.2022-1546_001)by the Italian Ministry of Education,MUR(Project Dipartimenti di Eccellenza,TECLA,Department of Earth and Environmental Sciences,University of Milano-Bicocca)。
文摘Mantle plumes and surface erosion and sediment deposition affect the modes of continental lithospheric rupturing in extensional tectonic settings,modulating the evolution of rifting margins.However,their relative contributions to the overall evolution of rifting margins and possible roles in the formation of microcontinent are still elusive.Here,we use coupled geodynamic and surface processes numerical modeling to assess the extent to which surface processes may determine the formation of microcontinent during lithospheric stretching in presence or absence of a mantle plume underneath.Our modeling results indicate that fast extension rates and hillslope(i.e.,diffusion)erosion promote ridge jump events and therefore the formation of microcontinents.On the contrary,efficient fluvial erosion and far-reaching sediment transport(i.e.,stream power erosion)inhibits ridge jump events and the formation of microcontinents.The ridge jump event and overall evolution in our numerical models is consistent with the shift from the Mascarene Ridge to the Carlsberg Ridge that determined the formation of the Seychelles microcontinent.We therefore speculate that hillslope erosion,rather than fluvial erosion,was predominant during the formation of the Seychelles,a possible indication of overall dry local climate conditions.
文摘BACKGROUND In addition to nodal lesions,over 30%of mantle cell lymphomas(MCLs)also have gastrointestinal involvement,characteristically presenting as multiple lymphomatous polyposis(MLP),which rarely involve the esophagus.Most related papers have been case reports,and no comprehensive studies have been conducted;thus,the actual clinical situation has remained unknown for a long time.AIM To elucidate the actual clinical situation of esophageal involvement of MCL presenting with MLP,including its prognosis.METHODS From January 2001 to December 2021,among MCL patients whose gastrointestinal lesions were histopathologically confirmed by endoscopic biopsy at our center,6 patients with MLP in the esophagus were selected.We retro-spectively examined the clinical features of these patients,including their prognosis.RESULTS In all patients,multiple lesions were present in the gastrointestinal tract other than the esophagus and in the lymph nodes throughout the body,and most patients also had lesions involving the bone marrow or spleen.Most of the treatments include chemotherapy,with a 50%survival period of less than 2 years and a 5-year survival rate of approximately 30%,indicating a poor prognosis.CONCLUSION Patients with esophageal involvement of the MCL who presented with MLP had a large tumor burden and poor survival.
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.82200215,82170193,and 82370197)the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(Grant No.2022-I2M-1-002)。
文摘Objective:Our previous studies have indicated potentially higher proliferative activity of tumor cells in Chinese patients with mantle-cell lymphoma(MCL)than those in Western.Given the success and tolerability of R-DA-EDOCH immunochemotherapy in treating aggressive B-cell lymphomas,we designed a prospective,phase 3 trial to explore the efficacy and safety of alternating R-DA-EDOCH/R-DHAP induction therapy for young patients with newly diagnosed MCL.The primary endpoint was the complete remission rate(CRR)at the end of induction(EOI).Methods:A total of 55 patients were enrolled.The CRR at the EOI was 89.1%[95%confidence interval(CI)78%±96%],and the overall response rate was 98.1%(95%CI 90%±100%).Most patients with bone marrow involvement quickly attained minimal residual disease(MRD)negative status,with a 95.7%rate at the EOI.Results:The 3-year progression-free survival(PFS)and overall survival rates were 66.3%and 83.2%,respectively.No patients discontinued treatment because of adverse events.Univariate analysis identified pathologic morphology and TP53 mutations as risk factors for PFS.However,high tumor proliferative activity and certain cytogenetic abnormalities showed no significant adverse prognostic significance.Conclusions:Intensive therapy based on a high cytarabine dose and continuously administered EDOCH achieved a high MRDnegative rate and provides an optional induction choice for young patients with MCL with high-risk factors.
文摘This retrospective case study investigates the clinical presentation of a 53-year-old female who underwent mantle field radiotherapy roughly 26 years ago. This patient presents with diffuse muscle atrophy and weakness in the cervical musculature, as well as sensory deficits in the upper extremities. We sought to compare our patient’s symptoms with other patients who had been formally diagnosed with Dropped Head Syndrome (DHS) by reviewing the existing literature. We found that the clinical presentation under investigation was consistent with other patients who had received radiotherapy for Hodgkins’s disease and were then diagnosed with DHS. Electromyography (EMG), nerve conduction studies, and a cervical MRI were unable to identify a separate neurological cause for the symptoms, but the MRI did confirm the presence of diffuse muscle atrophy in the cervical musculature. After reviewing the existing literature and imaging results, we compared our patient’s symptoms to those that define DHS, and both the time of onset, presenting symptoms, and progressing course are consistent with a diagnosis of Dropped Head Syndrome.
基金supported by the Jiangsu Innovation and Entrepreneurship Project(JSSCBS20211225).
文摘The North China Craton(NCC)experienced significant lithospheric thinning of over 100 km during the Mesozoic,accompanied by extensive magmatic activity and extensional tectonics.However,the timing and mechanism of this thinning remain the subjects of debate.This study presents zircon U-Pb ages,Hf isotopic data and whole-rock elemental and Sr-Nd isotopic compositions of the Guanshui monzonites and diorites in the eastern NCC.Zircon U-Pb dating reveals that both rock types formed at ca.130 Ma.The monzonites,characterized by high Mg^(#)(50.9-57.9),low Nb/U ratios(2.53-3.89)and depleted isotopic compositions,suggest derivation from asthenospheric mantle modified by slab-derived fluids.The diorites,distinguished by low SiO_(2)(49.5-50.8),high Mg^(#)(66.7-68.5)and an EM2-type enriched mantle isotopic signature,point to a lithospheric mantle source modified by subducted sediment melts.The coexistence of monzonites and diorites suggests a transition in magma source from lithospheric to asthenospheric mantle,implying that lithospheric thinning may have commenced around 130 Ma.The destruction of the NCC was likely driven by localized,small-scale drip-style detachment processes,rather than wholesale lithospheric removal.
基金The National Natural Science Foundation of China[Grant Nos.42172056,42202048]co-supported this work.
文摘Mafic rocks generated from subduction settings have recorded valuable source information about the mantle source.In this study,we present a comprehensive analysis of zircon U–Pb dating,whole-rock major and trace elements,and Sr–Nd isotopic data for the mafic gabbro located in the Yumen area,on the western part of the Yangtze Block,South China,aiming to constrain the processes of mantle metaso-matism within subduction settings.U–Pb dating results for zircon yield crystallization ages of 800 Ma for type 1 mafic gabbro and 753–734 Ma for type 2 mafic gabbro.Type 1 mafic gabbro exhibits higher SiO_(2)(44.13%–48.93%)and Al_(2)O_(3)content but lower total Fe2O3 and MgO content than type 2 gabbro(SiO_(2):41.02%–43.28%).These gabbros dis-play a high-Mg^(#)signature(52.50–62.81 for type 1,50.89–57.04 for type 2),while they are enriched in significant large-ion lithophile elements(LILEs:Rb,Ba,Sr,K)and depleted in high-field-strength elements(HFSEs:Zr,Hf,Nd,Ta,Ti),which indicates an arc-like element signature.The positive whole-rockεNd(t)values(type 1:3.5–4.4,type 2:5.6–6.3)combined with a narrow range of(^(87)Sr/^(86)Sr)_(i)(type 1:0.7035–0.7043,type 2:0.7035–0.7036)of both gabbro types suggest a depleted lithospheric mantle origin.There-fore,these mafic rocks may derive from a metasomatized spinel lherzolite mantle source(with amphibole)due to the interactions of the deep mantle source and subductionfluid materials.We propose that the long-term metasomatism recorded by mafic gabbro in this study supports the fact that the subduction during the Neoproterozoic contributed to the formation of a metasomatized mantle source in the Yumen area,western Yangtze Block,South China.
文摘The post-collisional Cenozoic basic volcanic rocks in NE Turkey show temporal variations in whole-rock lithophile element and highly siderophile element(HSE)systematics that are mainly associated with the nature of sub-continental lithospheric mantle(SCLM)sources and parental melt generation.So far,the traditional whole-rock lithophile geochemical data of these basic volcanic rocks have provided important constraints on the nature of SCLM sources.Integrated lithophile element and HSE geochemical data of these basic volcanic rocks also reveal the heterogeneity of the SCLM source,which is principally related to variable metasomatism resulting from previous subduction(s)and post-collisional mantle-crust interactions in an extensional setting.Lithophile element geochemical features suggest that the parental magmas have derived from metasomatized spinel-to garnet-bearing SCLM sources for Eocene and Miocene basic volcanic rocks with subduction signatures whereas originated from spinel-to garnet-bearing SCLM sources for Mio-Pliocene and Plio-Quaternary basaltic volcanic rocks without the subduction signature.Lithophile element and HSE geo-chemistry also reveal that Eocene and Miocene basic vol-canic rocks were affected by more pronounced crustal contamination than the basaltic volcanic rocks of Mio-Pliocene and Quaternary.Furthermore,the integrated lithophile element and HSE compositions of these basic volcanic rocks,together with the regional asymmetric lithospheric delamination model,reveal that the compositional variation(especially due to metasomatism)was significant temporally in the heterogeneity of the SCLM sources from which parental magmas formed during the Cenozoic era.
基金co-supported by the National Natural Science Foundation of China(Grant No.42272267)the Research Grants of Chinese Academy of Geological Sciences(Grant No.JKYQN202309)+3 种基金the National Key Research and Development Project"Key scientific issues of transformative technology"(Grant No.2019YFA0708604)the second Tibetan Plateau Scientific Expedition and Research Program(STEP)Grant(Grant Nos.2019QZKK0802,2019QZKK0901)the Scientific Investigation on Basic Resources of Ministry of Science and Technology(Grant No.2021FY100101)the Geological Survey of China(Grant Nos.DD20221630,DD20242126)。
文摘Magmatic periodicity is recognized in continental arcs worldwide,but the mechanism responsible for punctuated arc magmatism is controversial.Continental arcs in the Trans-Himalayan orogenic system display episodic magmatism and the most voluminous flare-up in this system was in early Eocene during the transition from subduction to collision.The close association of the flare-up with collision is intriguing.Our study employs zircon Lu-Hf and bulk rock Sr-Nd isotopes,along with mineral geochemistry,to track the melt sources of the Nymo intrusive complex and the role of mantle magma during the early Eocene flare-up of the Gangdese arc,Xizang.The Nymo intrusive complex is composed of gabbronorite,diorite,quartz diorite,and granodiorite which define an arc-related calc-alkaline suite.Zircon U-Pb ages reveal that the complex was emplaced between~50–47 Ma.Zircon Hf isotopes yieldεHf(t)values of 8.2–13.1,while whole-rock Sr and Nd isotopes yieldεNd(t)values of 2.7–6.5 indicative of magmatism dominated by melting of a juvenile mantle source with only minor crustal assimilation(~15%–25%)as indicated by assimilation and fractional crystallization modeling.Together with published data,the early Eocene magmatic flare-up was likely triggered by slab breakoff of subducted oceanic lithosphere at depths shallower than the overriding plate.The early Eocene magmatic flare-up may have contributed to crustal thickening of the Gangdese arc.This study provides important insights into the magmatic flare-up and its significant role in the generation of large batholiths during the transition from subduction to collision.
基金the Nationa1 Natural Science Foundation(Grant No.49673185)the Ministry of Science and Technology of China(Grant No.95-Pre-39).
文摘Using the secondary spinel standard, the authors have precisely measured theFe^(3+)/SIGMA Fe values of spinels in mantle xenoliths from Cenozoic basalts in eastern China, andestimated the oxygen fugacities recorded by 63 mantle xenoliths through olivine-orthopyroxene-spineloxygen barometry. The results indicate that the oxygen fugacities of the lithospheric mantle ineastern China are higher in the south than in the north. Among them, the oxygen fugacity of theNorth China craton lithospheric mantle is the lowest, similar to that of the oceanic mantle, whilethat of Northeast and South China are the same as that of the global continental mantle. Thevariations of mantle redox state in eastern China are mainly controlled by the C-O-H fluids derivedfrom the asthenospheric mantle. According to the mantle oxidation state, it can be concluded thatthe C-O-H fluids in the lithospheric mantle of eastern China consist mainly of CO_2 and minor H_2O,but CH_4-rich fluids should come from the asthenosphere where the oxidation state is lower.
基金the funding received from the Science and Engineering Research Board (SERB), Govt. of India under GAP 3291funded by Ministry of Earth Science (MoES) with project reference number Mo ES/ P.O. (Seismic) 8 (09)-Geochron/2012。
文摘Hydrous Cr-bearing uvarovite garnets are rare in natural occurrences and belong to the ugrandite series and exist in binary solid solutions with grossular and andradite garnets. Here, we report the occurrence of hydrous uvarovite garnet having Cr_(2)O_(3) upto 19.66 wt% and CaO of 32.12–35.14 wt% in the serpentinized mantle peridotites of Naga Hills Ophiolite(NHO), India. They occur in association with low-Cr diopsides. They are enriched in LILE(Ba, Sr), LREEs, with fractionating LREE-MREE [avg.(La/Sm)_(N) = 2.16] with flat MREE/HREE patterns [avg.(Sm/Yb)_(N) = 0.95]. Raman spectra indicate the presence of hydroxyl(OH^(–)) peaks from 3500 to 3700 cm^(-1). Relative abundances in fluid mobile elements and their close association with clinopyroxenes are suggestive of the formation of uvarovite garnets through low temperature metasomatic alteration of low-Cr diopsides by hydrothermal slab fluids. The high LREE concentration and absence of Eu anomaly in the garnet further attest to alkaline nature of the transporting slab dehydrated fluid rather the involvement of low-p H solution. The chemical characteristics of the hydroxyl bearing uvarovite hosted by the mantle peridotite of NHO deviate from the classical features of uvarovite garnet, and their origin is attributed to the fluid-induced metasomatism of the sub arc mantle wedge in a suprasubduction zone regime.
