Permian marine strata have gradually become a research focus in the world.The marine strata of the Late Permian Dalong Formation(P3d)in the Fenghai area,Fujian Province,have become more and more important as their geo...Permian marine strata have gradually become a research focus in the world.The marine strata of the Late Permian Dalong Formation(P3d)in the Fenghai area,Fujian Province,have become more and more important as their geochemical characteristics record important geological information and are a good indicator for recovering and reconstructing the paleosedimentary environments and tectonic attributes.The major elements,trace elements and rare earth elements were analyzed by XRF and ICP-MS,respectively.Based on the results of detailed field geological surveys,profile measurements as well as typical sample collection,the tectonic setting and provenance of Permian marine mudstone were comprehensively discussed.The results showed that the Dalong Formation(P3d)was deposited in an active continental margin tectonic environment as revealed by the relation between Fe2O3 + MgO and TiO2 and Al2O3/SiO2.The fingerprint characteristics of Mn,Fe,Co,Ni and REE and the ratio of U/Th,V/Cr,Sr/Ba,(La/Yb)N and V/(V +Ni)indicated that the sedimentary provenance was mainly derived from potassium feldspar,followed by muscovite.Sedimentary water bodies showed a gradually decreasing depositional rate trend,water depth gradually shallowing and paleo-salinity and productivity gradually increasing.Moreover,since transient delamination occurred during sedimentary processes,sedimentary water bodies showed obvious neritic characteristics.It was consistent with the results revealed by lithological and geochemical characteristics.Calcareous mudstone and siltstone transitioned into fine sandstone from bottom to top,indicating paleo-water bodies became shallow.The research results provided good reference and guidance for understanding Permian paleo-sedimentary environments and tectonic attributes of the Yong’an area,Fujian Province,southeastern China.展开更多
Objective: : To explore the value of a combined computed tomography(CT) and magnetic resonance imaging(MRI) in evaluating profound sensorineural deafness patients before cochlear implant(CI) surgery.Methods: A retrosp...Objective: : To explore the value of a combined computed tomography(CT) and magnetic resonance imaging(MRI) in evaluating profound sensorineural deafness patients before cochlear implant(CI) surgery.Methods: A retrospective analysis of 1012 cases of profound sensorineural deafness that received CI was performed.Results: A total of 96 cases were diagnosed with inner ear abnormalities including large vestibular aqueduct syndrome(LVAS, n ? 61), Michel deformity(n ? 3), cochlear incomplete partition I(n ? 2), cochlear incomplete partition II(n ? 6), cochlear hypoplasia with vestibular malformation(n ? 3), cochlear ossification(n ? 3), bilateral internal auditory canal obstruction(n ? 5) and internal auditory canal stenosis(n ? 2).Conclusion: High resolution CT(HRCT) can display bony structures while MRI can image the membranous labyrinth in preoperative evaluation for cochlear implantation. The combination of these two modalities provides reliable anatomical information regarding the bony and membranous labyrinths, as well as the auditory nerve.展开更多
基金supported by Opening Foundation of State Key Laboratory of Continental Dynamics, Northwest UniversityOpening Foundation of State Key Laboratory for Mineral Deposits Research, Nanjing University (20-15-05)
文摘Permian marine strata have gradually become a research focus in the world.The marine strata of the Late Permian Dalong Formation(P3d)in the Fenghai area,Fujian Province,have become more and more important as their geochemical characteristics record important geological information and are a good indicator for recovering and reconstructing the paleosedimentary environments and tectonic attributes.The major elements,trace elements and rare earth elements were analyzed by XRF and ICP-MS,respectively.Based on the results of detailed field geological surveys,profile measurements as well as typical sample collection,the tectonic setting and provenance of Permian marine mudstone were comprehensively discussed.The results showed that the Dalong Formation(P3d)was deposited in an active continental margin tectonic environment as revealed by the relation between Fe2O3 + MgO and TiO2 and Al2O3/SiO2.The fingerprint characteristics of Mn,Fe,Co,Ni and REE and the ratio of U/Th,V/Cr,Sr/Ba,(La/Yb)N and V/(V +Ni)indicated that the sedimentary provenance was mainly derived from potassium feldspar,followed by muscovite.Sedimentary water bodies showed a gradually decreasing depositional rate trend,water depth gradually shallowing and paleo-salinity and productivity gradually increasing.Moreover,since transient delamination occurred during sedimentary processes,sedimentary water bodies showed obvious neritic characteristics.It was consistent with the results revealed by lithological and geochemical characteristics.Calcareous mudstone and siltstone transitioned into fine sandstone from bottom to top,indicating paleo-water bodies became shallow.The research results provided good reference and guidance for understanding Permian paleo-sedimentary environments and tectonic attributes of the Yong’an area,Fujian Province,southeastern China.
基金supported by the Cochlear Implantation Program of HunanNational Basic Research Program of China (2012CB967904)
文摘Objective: : To explore the value of a combined computed tomography(CT) and magnetic resonance imaging(MRI) in evaluating profound sensorineural deafness patients before cochlear implant(CI) surgery.Methods: A retrospective analysis of 1012 cases of profound sensorineural deafness that received CI was performed.Results: A total of 96 cases were diagnosed with inner ear abnormalities including large vestibular aqueduct syndrome(LVAS, n ? 61), Michel deformity(n ? 3), cochlear incomplete partition I(n ? 2), cochlear incomplete partition II(n ? 6), cochlear hypoplasia with vestibular malformation(n ? 3), cochlear ossification(n ? 3), bilateral internal auditory canal obstruction(n ? 5) and internal auditory canal stenosis(n ? 2).Conclusion: High resolution CT(HRCT) can display bony structures while MRI can image the membranous labyrinth in preoperative evaluation for cochlear implantation. The combination of these two modalities provides reliable anatomical information regarding the bony and membranous labyrinths, as well as the auditory nerve.
