The discovery of TiO_(2)-Ⅱ,the α-PbO_(2)-structured high-pressure polymorph of rutile,in the Suizhou L6 chondrite

We report the discovery of TiO_(2)-Ⅱ in the unmelted rock of the shocked Suizhou L6 chondrite.Natural TiO_(2)-Ⅱ was previously found in ultrahigh-pressure metamorphic and mantle-derived rocks,terrestrial impact structures,and tektite.Our microscopic,Raman spectroscopic,electron microprobe and transmission electron microscopic investigations have revealed:(1) All observed TiO_(2)-Ⅱ grains are related with ilmenite and pyrophanite;(2) TiO_(2)-Ⅱ occurs as needle-and leaf-shaped inclusions in llmenite and patch-,tape-shaped body in pyrophanite;(3)The composition of TiO_(2)-Ⅱ is identical with that of its precursor rutile;(4) The Raman spectrum of TiO_(2)-Ⅱ is in good agreement with that of natural and synthesized α-PbO_(2)-type TiO_(2);(5) TiO_(2)-Ⅱ occurs mainly in the form of well-ordered nano-domains and small mis-orientation among the domains can be observed.(6) All electron diffraction reflections from TiO_(2)-Ⅱ can be indexed to α-PbO_(2)structure in space group Pbcn with lattice parameters of a=4.481 ?,b=5.578 A and c=4.921 A;(7) The exsolution inclusions of rutile from host ilmenite are mostly connected with an alternation process along the lamellar twinning plane of ilmenite induced by shockinduced high pressure and high temperature;(8) The P-T regime of 20-25 GPa and 1000 ℃ estimated for the Suizhou unmelted rock is suitable for phase transition of rutile into TiO_(2)-Ⅱ phase.

The breakdown of diopside to(Ca,Mg)SiO_(3)perovskite–(Mg,Ca,Fe)SiO_(3)glass–(Mg,Ca)SiO_(3)glass–(Mg,Ca)SiO_(3)majorite in a melt vein the Suizhou L6 chondrite

The Suizhou meteorite is a heavily shocked and melted vein-containing L6 chondrite.It contains a minor amount of diopside with a(Ca_(0.419)Mg_(0.466)Fe_(0.088))SiO_(3)composition,and a shock-metamorphosed diopside grain associated with ringwoodite and lingunite was found in a melt vein of this meteorite.Our electron microprobe,transmission electron microscopic and Raman spectroscopic analyses revealed four silicate phases with different compositions and structures inside this shock-metamorphosed diopside grain,termed phase A,B,C and D in this paper.Phase A is identified as orthorhombic(Ca_(0.663)-Mg_(0.314))SiO_(3)-perovskite which is closely associated with phase B,the vitrified(Mg_(0.642)Ca_(0.290)Fe_(0.098))SiO_(3)perovskite.Phase D is assigned to be(Mg_(0.578)Ca_(0.414))SiO_(3)majorite which is associated with phase C,the vetrified Carich Mg-perovskite with a(Mg_(0.853)Ca_(0.167))SiO_(3)composition.Based on high-pressure and high-temperature experiments,the diopside grain in the melt vein of the Suizhou meteorite would have experienced a P–T regime of 20–24GPa and 1800–>2000℃.Such P–T conditions are high enough for the decomposition of the diopside and the formation of four different silicate phases.The orthorhombic(Ca_(0.663)Mg_(0.314))SiO_(3)perovskite found in the Suizhou L6 chondrite might be considered as the third lower-mantle silicate mineral after bridgmanite and davemaoite after the detailed analyses of its crystal structure and physical properties being completed.

Redistribution of Trace Elements During Shock-inducd Melting and Phase Tranzition of Minerals in the Suizhou l6 Chondrite

The Suizhou meteorite is an L6 chondrite. This meteorite is consisted of olivine, low-Ca pyroxene, plagioclase, FeNi metal, troilite, whitlockite, chlorapatite, chromite and ilmenite. Olivine and pyroxene grains display shock-induced mosaic texture, and most plagioclase grains were melted and transformed to maskelynite. This meteorite contains a few very thin shock-produced melt veins ranging from 20 to 100 μm in width. They are chondritic in composition and contain abundant high-pressure minerals in two assemblages. One is the coarse-grained assemblage of ringwoodite, majorite, lingunite with minor amount of tuite, xieite, the CF-phase, akimotoite and amorphized perovskite, and the fine-grained assemblage (the melt vein matrix) composed of majorite-pyrope garnet, magnesiowüstite. FeNi metal and troilite in the Suizhou shock veins were molten and occur as small intergrowth grains or veinlets filling the interstices of garnet crystals or cracks in the vein matrix. It was revealed that olivine, pyroxene and plagioclase in the Suizhou shock veins have transformed in solid state to their high-pressure polymorphs ringwoodite, majorite, and lingunite, respectively, without change in their chemical compositions.

Transmission electron microscopic study of the fine-grained vein matrix in the Suizhou L6 meteorite

The mineralogy of shock vein matrix in the Suizhou meteorite has been investigated by optical and transmission electron microscopy. It was revealed that the vein matrix is composed of majorite-pyrope garnet, magnesiowüstite, and ringwoodite, with FeNi–FeS intergrowths. The observation and character of ring-like selected electron diffraction(SAED) patterns indicate that the idiomorphic garnet crystals in the vein matrix have different orientations. The polycrystalline nature of magnesiowüstite is also confirmed by a ring-like SAED pattern.Both garnet and magnesiowüstite crystals showed sharp diffraction spots, signifying the good crystallinity of these two minerals. The SAED pattern of cryptocrystalline ringwoodite shows only diffuse concentric diffraction rings. FeNi metal and troilite(FeS), which were molten during the shock event, occur in the matrix as fine eutectic FeNi–FeS intergrowths filling the interstices between garnet and magnesiowüstite grains. Based on the phase diagram of the Allende chondrite and the results of this TEM study, it is inferred that majorite-pyrope garnet first crystallized from the Suizhou chondritic melt at 22–26 GPa,followed by crystallization of magnesiowüstite at 20–24 GPa, and then ringwoodite at 18–20 GPa. The eutectic intergrowths of FeNi-metal and troilite are proposed to have crystallized during meteorite cooling and solidified at the last stage of vein formation.

襄阳都市圈旅游一体化发展路径研究

中国式现代化和新发展格局对区域旅游一体化提出了新的要求。旅游一体化是城市一体化的重要组成部分,襄阳都市圈旅游一体化发展问题要立足汉江流域、南襄盆地、中西部新通道的大格局来分析,最为关键的就是“襄十随神”城市群旅游一体化。襄阳都市圈各城市地域相接、交通相连、文脉相通,共饮一江汉水,旅游一体化基础良好。围绕五大主题游线,重点做好增加旅游一体化合作收益、拓展襄阳旅游中心城市功能、谋划城市群旅游新格局、丰富城市群旅游形象和业态等方面的工作。

Synchrotron radiation X-ray diffraction in situ study of fine-grained minerals in shock veins of Suizhou meteorite

The synchrotron radiation X-ray diffraction technique developed for in situ study ahigh pressure and temperature has also been used to investigate microscopic mineral inclusionsin ultrahigh-pressure metamorphic rocks and deep-mantle samples. Present study added twomore examples of successful utilization of synchrotron radiation X-ray diffraction technique for insitu investigations of fine-grained (0.5―30 μm in size) minerals in very thin shock melt veins othe Suizhou meteorite: ( i ) X-ray diffraction measurement of extremely small-sized vein matrixminerals, and (ii) identification of the micron-sized new mineral tuite embedded in the vein matrixIt has been revealed that the fine-grained vein matrix consists of well crystallized garnet, kamacite and troilite, and the powder diffraction pattern consisting of 17 lines with d-values, intensities( I ), relative intensities (I/Io) and Miller indices, as well as the cell parameters for the new mineratuite has also been successfully obtained. The result of present investigations has enriched thecontent of dynamic high-pressure mineralogy and that of Earth’s mantle geochemistry.

湖北随州叶家山墓地M126出土铜器科学分析

本文通过科技检测手段对叶家山M126出土铜器进行了分析。结果表明,经分析的10件器物中,有7件为铅锡青铜制成,包括6件容器和1件兵器,有3件锡青铜,全部为容器。这批铜器制作采用块范铸造工艺。祖己爵M126:16为一件商代器物。其他器物分属A类和C类普通铅的范畴。其他族属铭文铜器中,一部分器物使用了与曾国铜器相同或相似的矿料,另一部分器物与曾国铜器使用的矿料不同,体现了西周早中期青铜物料流通信息,部分以器物组的形式流通。

NaAlSi_3O_8-hollandite and other high-pressure minerals in the shock melt veins of the Suizhou meteorite

The Suizhou L6 chondrite contains a few very thin shock melt veins of 0.02-0.09 mm in width. In spite of small width of the veins, shock-induced high-pressure phases, such as coarse-grained NaAlSi3O8-hollandite, ringwoodite, majorite and fine-grained matrix majorite-pyropess have been discovered in these veins. NaAlSi3O8-hollandite, the high-pressure phase of plagioclase, in Suizhou shock veins occurs as a single phase mineral, no silicate glassy phase, such as albitic glass, was incorporated with it. The presence of above-mentioned high-pressure phases constrains the high pressure (up to 23-24 GPa) and high temperature (up to 1900-2000℃) regime in Suizhou shock veins, and indicates that the duration of high-pressure regime in the veins should be long enough (a few seconds) for phase transformation and crystallization of minerals under pressure. The discovery of the first natural single-phase crystalline NaAlSi3O8- holland-ite in Suizhou meteorite is of important significance in understanding the Earth’

Petrogenesis and Tectonic Implications of Peralkaline A-Type Granites and Syenites from the Suizhou-Zaoyang Region,Central China

In this study, we present systematic petrological, geochemical, LA-ICP-MS zircon U-Pb ages and Nd isotopic data for the A-type granites and syenites from Suizhou-Zaoyang region. The results show that the peralkaline A-type granites and syenites were episodically emplaced in Suizhou-Zaoyang region between 450±3 and 441±7 Ma which corresponds to Late Ordovician and Early Silurian periods, respectively. Petrologically, the syenite-peralkaline granite association comprises of nephefine normative-syenite and alkaline granite in Guanzishan and quartz normative syenite and alkafine granite in Huangyangshan. The syenite-granite associations are ferroan to alkali in composition. They depict characteristics of typical OIB （oceanic island basalts） derived A-type granites in multi-elements primitive normalized diagram and Ybffa vs. Y/Nb as well as Ce/Nb vs. Y/Nb binary plots. Significant depletion in Ba, Sr, P, Ti and Eu indicates fractionation of feldspars, biotite, amphiboles and Ti-rich augite. The values of eNd（t） in Guanzishan nepheline syenite and alkaline granite are ＋1.81 and ＋2.26, respectively and the calculated two-stage model age for these rocks are 1 040 and 1 003 Ma, respectively. On the other hand, the Huangyangshan alkaline granite has eNd（t） values ranging from ＋2.61 to ＋3.46 and a relatively younger two-stage Nd model age values ranging from 906 to 975 Ma, respectively. Based on these data, we inferred that the Guanzishan nepheline syenites and granites were formed from fractional crystallization of OIB-like basic magmas derived from upweliing of metasomatized lithospheric mantle. The Huangyangshan quartz syenite and granite on the other hand, were formed from similar magmas through fractional crystallization with low input from the ancient crustal rocks. Typically, the rocks exhibit Al-type granite affinity and classified as within plate granites associated with the Ordovician crustal extension and the Silurian rifting.

FISSION-TRACK AGE OF SUIZHOU METEORITE

An average ancient track density of(7.6±1.1)×10~3/cm^2 has been obtained for pyroxene in Suizhou meteorite based on ancient and neutron-induced fission-track density measurements. The result is consistent with the ancient track density of 8.4×10~3/cm^2

基于测雨雷达与地面雨量站的山洪模拟及灾害预警时效分析

传统暴雨山洪预警主要依靠地面雨量站降雨数据,易出现虚警漏警或难以满足预警时效的情况。流域面雨量实时监测和前移山洪预警响应时间是满足山洪灾害防御目标的重要技术手段,测雨雷达技术的应用也为山洪灾害防治提供了新的预警思路。以湖北柳林镇2021年8月12日暴雨山洪事件为例,采用模块化分布式水文模型(MDHM)模拟山洪过程并进行预警分析,对比基于测雨雷达、地面雨量站降雨输入条件下的灾害预警时效,评估两种降雨数据源下山洪预警的有效性和可靠性,结果表明测雨雷达预报降雨结合水位陡涨率预警法能显著提高预警效果,可为暴雨山洪防灾减灾提供技术支撑。

A SURVEY OF SUIZHOU METEORITE SHOWER

A chondrite shower occurred on April 15, 1986 in the vicinity of Dayianpo Village, Suizhou City, Hubei Province. It is the second large scale meteorite shower following the Jilin Meteorite Shower.

旅游发展、交通基础设施与农民增收的动态关联研究——以湖北省“襄十随神”区域为例

探索旅游发展、交通基础设施与农民增收三者之间的动态关系,对于推进区域协同发展具有重要的启示意义。文章基于湖北省“襄十随神”四市(区)2004—2021年面板数据,运用向量自回归模型,讨论了四地旅游发展、交通基础设施和农民增收三者之间的动态关系。结果表明:“襄十随神”四市(区)旅游发展、交通基础设施与农民增收之间存在长期均衡关系;旅游发展明显促进了交通基础设施的完善,旅游发展与交通基础设置完善对农民增收具有较强的推动作用;农民增收对旅游发展和交通基础设施完善的影响较弱。在实证分析和考虑地区差异与关联性的基础上,提出了协调、共生、一体化的发展建议,以期为“襄十随神”区域协同发展提供一定借鉴。

试论随州吴山铜钼多金属矿地质特征及找矿方向

吴山铜钼多金属矿主要分布在桐柏-大别山钼多金属成矿带西南部的区段上,区内有着较为复杂的地层产出,并有着频繁而又强烈的构造岩浆活动,成矿地质条件优越。下文中主要对该矿成矿地质特征进行详细分析和阐述,在此基础上,探究分析该矿矿床成因,并对找矿标志进行总结指出今后的找矿方向,希望能对区内地质找矿工作提供一些指示作用。

Shock-produced akimotoite in the Suizhou L6 chondrite

Shock-produced akimotoite was identified in the Suizhou chondritic meteorite, which occurs in two kinds of occurrence. The first is the irregular layers of akimotoite up to 4 ?m in thickness occurring in fractures and cracks of low-Ca pyroxene enclosed in the shock veins. The second is the zonal polycrystalline aggregates of akimotoite in shocked pyroxene grains close to the shock vein, where akimotoite occurs in a zonal area in between pyroxene and Mg Si O3-glass as irregular small clumps up to 5 ?m in size. This investigation suggests a solid-state transformation mechanism of pyroxene to akimotoite, and that akimotoite should have nucleated and grew in the area with abundant defects caused by shock deformation because the defect significantly enhances the solid-state reactivity and the kinetics of nucleation of high-pressure phase. The spatial relationship among the composed grains of pyroxene, akimotoite and Mg Si O3-glass(possibly vitrified perovskite) demonstrates a temperature gradient from the vein wall to the unmelted chondritic meteorite.

Occurrence andmineral chemistry of chromite and xieite in the Suizhou L6 chondrite

The occurrence andmineral chemistry of chromite and its high-pressure phase xieite in the Suizhou meteorite were studied by different modern micromineralogical techniques.Three types of occurrences for chromite were observed in the Suizhou L6 chondrite:coarse chromite grains,cluster of chromite fragments in molten plagioclase,and exsolution lamellar chromite in olivine.All the chromite grains of the first two types are remarkably similar in chemical compositions,but the composition of exsolution chromite is inhomogeneous and variable in Al 2 O 3 content.Xieite is a post-spinel CT-phase of chromite firstly found in the Suizhou meteorite.Three types of occurrences of xieite have also been revealed in this meteorite:coarse xieite grains,complex three-zone-grains consisting of the inner xieite,the intermediate lamellae-like CF-phase and the outer chromite phase,and two-phase-grains consisting of xieite and one of the high-pressure silicateminerals lingunite,ringwoodite or majorite.The curved boundary between xieite and the silicate half in two-phase grains is indicative of some partial or even full melting of the silicate phase.EPMA and EDS results show that the compositions of xieite inside/contacting the shock veins are also identical to that of chromite outside the veins.However,some element diffusion appeared in between the xieite and the silicate half in the two-phase grains,namely,some of Al 3+ from lingunite,or Fe 2+ from ringwoodite migrated to xieite,and some of Cr 3+ migrated from xieite to lingunite or ringwoodite.Majorite in two-phase grains shows remarkable decrease of SiO 2 and MgO,and notable increase of Al 2 O 3 and CaO,indicating that its hostmineral pyroxene was fully molten and mixed with the surrounding silicate melt of the vein matrix.The complexity inmineral chemistry of these two-phase grains in shock veins can be explained by the much higher shock peak temperature in shock veins (1800-2000°C) than in unmelted main body (～1000°C),and by the much lower density of the silicateminerals (2.6-3.3 g/cm 3) than that of chromite (4.43 g/cm 3).Being a refractory and a relatively high-impedance material,chromite is chemically more stable and easier to reflect shock wave into the silicate half causing the partial or even full melting of silicate phases,upon which some diffusion of elements between the two phases themselves,or even mixing of molten pyroxene and the surrounding silicate melt.

“襄十随神”区域经济特征及发展战略调整——以十堰市为例

“襄十随神”作为湖北省发展战略的一个重要组成部分,是“一主引领、两翼驱动”中的重要一“翼”。随着国家新的经济发展格局的调整,湖北省及“襄十随神”各市县均对其发展战略进行了重大调整。在国家将湖北建成“建设全国构建新发展格局先行区”的大战略下,“襄十随神”各地须适当优化发展战略和规划,实行错位发展。十堰市主要应突破性发展“一主四优多支撑”产业。

随州南站屋盖结构设计和分析

随州南站站房采用24个伞状单元体呈现银杏叶的造型,结构设计时以H形截面弦杆形成的异形钢桁架作为主受力骨架,结合分叉圆钢管、吊杆、水平圆管桁架等形成完整单元体结构。单元体结构与顶部波浪形正交钢梁体系连接,形成了站房屋盖整体结构。屋盖结构体系复杂,单元体根部尺寸收缩,采用屈曲分析得到了结构的屈曲模态及屈曲因子,第一阶屈曲模态位于伞状单元体结构根部位置,并进一步对屋盖结构进行了荷载-位移全过程分析,以保证屋盖结构的整体承载力。设计时在单元体结构中采用了十字工形组合钢柱及鼓形节点,利用有限元分析和试验的手段对此两种特殊结构构造进行了验证,以确保关键部位的承载力。单元体结构外表皮采用张拉索-膜结构形成的金黄色ETFE膜完整呈现了建筑效果。

湖北随州地区孕妇α-地中海贫血产前筛查及基因型分布特点研究

目的:探讨随州地区孕妇产前α-地中海贫血(简称α-地贫)检出情况及基因型分布特点,为该地区地贫防控提供科学依据。方法:选择进行产前检查的5275例孕妇,采用红细胞参数分析联合血红蛋白成分进行初筛,对初筛阳性者进行血红蛋白电泳和基因型检测。结果:5275例孕妇中,初筛α-地贫表型阳性581例,阳性率11.01%。581例α-地贫表型阳性孕妇进行α地贫基因检测,185例携带α-地贫基因,检出率为31.84%。在185例确诊的α-地贫基因携带孕妇中,共检出静止型α-地贫(-α^(3.7)/αα、-α^(4.2)/αα、α——(QS125)α/αα、α^(WS122)α/αα、α^(WS142)α/αα)、轻型(-SEA/αα、-α^(3.7)/-α^(3.7)、-α^(3.7)/-α^(4.2)、-α^(4.2)/-α^(4.2)、-α^(3.7)/α^(QS125)α、-α^(3.7)/α^(WS122)α、-α^(3.7)/α^(WS142)α、-α^(4.2)/α^(WS122)α)和中间型(-SEA/-α^(3.7)、-SEA/-α^(4.2))3种α-地贫基因型,其中以静止型(63.24%)和轻型α-地贫(32.43%)居多。α-地贫组与非α-地贫组孕妇血液学参数比较,α-地贫组血红蛋白(Hb)、红细胞体积(MCV)、血红蛋白浓度(MCH)、血红蛋白A_(2)(HbA_(2))均低于非α-地贫组(均P<0.05)。不同基因型α-地贫孕妇血液学参数比较差异有统计学意义(均P<0.05),组间Hb、MCV、MCH、HbA_(2)比较,静止型>轻型>中间型,差异有统计学意义(均P<0.05)。结论:随州市孕妇α-地贫表型阳性率及基因携带率均较高,基因型多样,应加强该地区孕妇的产前α-地贫筛查,防止重度地贫患儿出生。

湖北随州地区孕妇2772例β-地中海贫血基因型分布及血常规参数变异调查研究

目的:探讨湖北随州地区孕妇β-地中海贫血基因型分布特征及其血常规参数变异情况。方法:收集进行地中海贫血筛查的孕妇2772例,对β-地中海贫血血液学表型阳性者进行β-地中海贫血基因检测。将检出β-地中海贫血基因突变的孕妇纳入β-地中海贫血组,并按1∶1比例随机选取非地中海贫血孕妇纳入非地中海贫血组。比较β-地中海贫血组与非地中海贫血组血常规参数。比较β+突变和β0突变孕妇血常规参数。结果:2772例接受地中海贫血筛查的孕妇中,经血常规参数分析初筛阳性362例(13.06%),进一步血红蛋白(Hb)电泳分析发现β-地中海贫血血液学表型阳性91例(3.28%)。β-地中海贫血基因检测发现82例(2.96%)存在β-地中海贫血基因突变,其中4种β+突变(IVS-Ⅱ-654、CAP、-28、-29)共37例(45.12%),5种β0突变(CD71-72、CD27-28、CD41-42、CD17、CD14-15)共45例(54.88%),占比最高的3种基因型分别是IVS-Ⅱ-654(36.59%)、CD41-42(23.17%)和CD17(18.29%)。β-地中海贫血组中红细胞分布宽度(RDW)≥15%、Hb<110 g/L、平均红细胞体积(MCV)<82 fl、平均红细胞血红蛋白含量(MCH)<27 pg以及MCV<82 fl和(或)MCH<27 pg的孕妇比例显著高于非地中海贫血组(均P<0.05)。β+突变组RDW显著低于β0突变组,而Hb、MCV和MCH显著高于β0突变组(均P<0.05)。结论:湖北随州地区孕妇β-地中海贫血基因型复杂多样,以IVS-Ⅱ-654和CD41-42突变为主,且不同基因型的血液学参数具有显著差异,联合血液学筛查具有一定的经济效益。