THE METAMORPHIC FEATURE,AGE AND MECHANISM OF AMUGANG GROUP IN NORTHERN TIBET

Amugang Group is distributed mainly over Amugang, Jiangai Mountain, Mayigangri,Gemuri and Qiagela,etc. lt includes Gemuri Formation and Qiagela Formation. They had even been thought of the crystalline basement of Qiangtang terrain. However, Gemuri Formation and Qiagela Formation are not alike in the protolithes, metamorphism and deformation, rock association,etc.In fact, they are different in mechanism.Gemuri Formation is composed of high\|Pressure, low\|temperature glaucophane greenschist\|faci metamorphic rocks. The petrolithes of the blueschists are glaciomarine conglomerates and basalts from the Southern Qiagtang area. The typical mineralogy include: glaucophane+ epidote + calcite +stilpnomelane and stilpnomelane+chlorite+sericite+ quartz+ glaucophane. P.T conditions for the metamorphism of blueschist are estimated to be 0 6～0 7GPa and 320～400℃.The 40 Ar/ 39 Ar dating of the crossite has yielded good plateau age of (222 5±3 7)Ma,which represents the formation of Gemuri Formation.Qiagela Formation comprises schist series, marbles, Gneisses and plagioamphiboles. The protolithes of them are a suit of argillaceous sandstones, arkoses, carbonates and mafic volcanic rocks. The Sm\|Nd isochron age of the metamorphic mafic volcanic rocks is (268 0±5 6)Ma, which shows that The age of the protolithes is early Dias. The typical mineralogy include: Muscovite+biotite+plagioclase+quartz; garnet+kyanite+ staurolite+ biotite+ muscovite+plagioclase+quartz; amphibole+ plagioclase±garnet+ quartz. They are meos\|pressure,meso\|temperature low amphibole\|faci metamorphic rocks. Qiagela Formation is coexistent with the late Triassic and the early Jurassic volcano\|magmatic arc in space and overlapped by the triassic limestones of Xiaocaka Formation. So,it is suggested that the formation of Qiagela Formation be between the late Dias and the late Triassic period. Its genesis is relative to the thermal current provided by magmatic activity.

Endogamous marriage and the prevalence of hemoglobin E in ethnic groups of northern Thailand

Objective:To investigate the impact of the endogamous marriage culture on the prevalence of the hemoglobin E(HbE) recessive variant.Methods:The prevalence of the hemoglobin E(HbE)recessive variant was determined by dot-blot hybridization in 4 endogamous villages(1 Mlabri and 3 Htin ethnic groups) in comparison with 9 other nearby non-endogamous populations.Results:Although the overall HbE prevalence in the population studied(8.44%,33/391)was not significantly different from that of the general southeast Asian population,a high prevalence and individuals with homozygous HbE were observed in two villages,the Mlabri from Wiang Sa district and the Htin from Thung Chang district of Nan province(26.3%and26.9%,respectively).The low HbE allelic frequency noticed in some endogamous populations suggests that not only endogamy but also other evolutionary forces,such as founder effect and HbE/β-thalassemia negative selection may have an effect on the distribution of the HbE trait.Conclusion:Our study strongly documents that cultural impact has to be considered in the extensive prevalence studies for genetic disorders in the ethnic groups of northern Thailand.

Plate tectonic control on the formation and tectonic migration of Cenozoic basins in northern margin of the South China Sea

The tectonic evolution history of the South China Sea(SCS) is important for understanding the interaction between the Pacific Tectonic Domain and the Tethyan Tectonic Domain,as well as the regional tectonics and geodynamics during the multi-plate convergence in the Cenozoic.Several Cenozoic basins formed in the northern margin of the SCS,which preserve the sedimentary tectonic records of the opening of the SCS.Due to the spatial non-uniformity among different basins,a systematic study on the various basins in the northern margin of the SCS constituting the Northern Cenozoic Basin Group(NCBG) is essential.Here we present results from a detailed evaluation of the spatial-temporal migration of the boundary faults and primary unconformities to unravel the mechanism of formation of the NCBG.The NCBG is composed of the Beibu Gulf Basin(BBGB),Qiongdongnan Basin(QDNB),Pearl River Mouth Basin(PRMB) and Taixinan Basin(TXNB).Based on seismic profiles and gravity-magnetic anomalies,we confirm that the NE-striking onshore boundary faults propagated into the northern margin of the SCS.Combining the fault slip rate,fault combination and a comparison of the unconformities in different basins,we identify NE-striking rift composed of two-stage rifting events in the NCBG:an early-stage rifting(from the Paleocene to the Early Oligocene) and a late-stage rifting(from the Late Eocene to the beginning of the Miocene).Spatially only the late-stage faults occurs in the western part of the NCBG(the BBGB,the QDNB and the western PRMB),but the early-stage rifting is distributed in the whole NCBG.Temporally,the early-stage rifting can be subdivided into three phases which show an eastward migration,resulting in the same trend of the primary unconformities and peak faulting within the NCBG.The late-stage rifting is subdivided into two phases,which took place simultaneously in different basins.The first and second phase of the early-stage rifting is related to back-arc extension of the Pacific subduction retreat system.The third phase of the earlystage rifting resulted from the joint effect of slab-pull force due to southward subduction of the proto-SCS and the back-arc extension of the Pacific subduction retreat system.In addition,the first phase of the late-stage faulting corresponds with the combined effect of the post-collision extension along the Red River Fault and slab-pull force of the proto-SCS subduction.The second phase of the late-stage faulting fits well with the sinistral faulting of the Red River Fault in response to the Indochina Block escape tectonics and the slab-pull force of the proto-SCS.

Ecology and social system of northern gibbons living in cold seasonal forests

Gibbons in China represent the northernmost margin of present day gibbon species distribution （around N25°）. Compared to tropical habitats, northern gibbon habitats are characterized by low temperatures and remarkable seasonal variation in fruit abundance How gibbons adapt to their cold and seasonal habitats and what ecological factors affect their sociality are key questions for understanding their ecology and social system evolution, the elucidation of which will contribute to the conservation of these special populations/species. According to preliminary short-term studies, northern gibbons consume more leaves and use larger home ranges than tropical gibbons. Interestingly, some Nomascus groups consist of more than one adult female. However, these preliminary results are not well understood or incorporated into current socio-ecological theories regarding gibbon species. To better understand northern gibbons, our team has systematically studied three habituated groups of Nomascus concolor, three groups of N. nasutus, and two habituated groups of Hoolock tianxing since 2002. In this paper, we stress the challenges facing gibbons living in northern habitats and summarize their behavioral adaptations to their harsh environments. We also describe the northern gibbon social system and discuss the potential relationships between their ecology and sociality. Finally, we highlight future research questions related to northern gibbons in China.

从体部指数值探讨中国族群体部特征的共性

目的探讨中国族群体部特征的共性。方法对中国62个族群的8项体部指数值进行分析。结果聚类分析发现,男性52个族群、女性59个族群聚入了北方族群为主的混合组及南方族群为主的混合组。8个汉族族群分别聚入各个组中,没有聚合出汉族组。体部指数的分型结果表明,长躯干型、中胸型、宽肩型、宽骨盆型和中腿型是中国男性族群主要的体部类型。中躯干型、宽胸型、宽肩型、宽骨盆型和中腿型是中国女性族群主要的体部类型。这表现出中国各族群体部特征具有明显的一致性。中国族群体部特征的一致性与其族源相近有关,汉族在中国各个族群交流融合过程中起了重要作用。在汉族的历史上,出现过多次大规模的人口迁徙。北方少数民族南下融入北方汉族,北方汉族南下促进了南方汉族的形成,使得南方汉族与北方汉族体部特征具有相似性,也促进了南方少数民族融入南方汉族。此外,迁入少数民族地区的汉族也逐渐融入少数民族中。结论中国各族群体部特征存在明显的共性。

基于BMT测定的准噶尔盆地北部吐谷鲁群空间分布特征

准噶尔盆地作为目前砂岩型铀矿找矿的主攻盆地之一,自21世纪初在其北部地区始—渐新统乌伦古河组中发现了工业铀矿化之后,近20年来几乎未系统开展过铀矿找矿工作,因此对于深部地层是否存在铀矿化仍不清楚。随着近年来我国铀矿找矿工作在准噶尔盆地北部地区的持续投入,在吐孜托依拉逆冲断裂上盘的下白垩统吐谷鲁群砂岩中发现层间氧化带,这说明该层可能存在较好的砂岩型铀矿。但在吐孜托依拉逆冲断裂下盘因下白垩统吐谷鲁群埋深较大,前人开展地质物探工作较少,故其埋深、厚度、分布范围等情况尚不明确。文章引入了宽频大地电磁测深方法,通过数据采集、处理,采用Occam反演技术,获得了可靠的反演电阻率断面,结合钻孔资料,通过地质解释,得到了下白垩统吐谷鲁群埋深图、厚度图等研究成果。获得的准噶尔盆地北部找矿目标层下白垩统吐谷鲁群空间分布特征,能够为研究区地质结构研究和圈定铀矿找矿前景有利区域提供支撑。

中国古代北方民族丧葬仪式、特点及影响

葬礼作为人生的最后一项礼仪,是生者举行的哀悼和纪念死者的仪式。作为一种文化习俗,北方少数民族的丧葬仪式意蕴丰富,形态多样,并随着社会发展而不断演变。古代北方少数民族的丧葬仪式,呈现出共有性、宗教色彩浓厚、“游牧”特征、丧葬形式多样性等四个特点。北方民族丧葬仪式的变化,既有北方少数民族之间相互影响的因素,又有汉族对北方少数民族影响的因素。北方少数民族丧葬仪式的鲜明特征、汉化的发展趋势,体现了民族交往交流交融的多元化形态,是观察历史上民族交往交流交融的重要窗口。

北魏赐客制及其对民族交融的影响

拓跋珪恢复代国之时,实行使归顺者能够获得客身份的做法。北魏建国后,道武帝拓跋珪使赐客的规定制度化。北魏国家使“归国”少数族首领能够成为授客对象;而对“归国”汉人而言,只有上层群体,可以获得“客”身份。北魏国家对客实行了优待的措施,使少数族和汉族的客能够受封爵位和受任职官,并且,还能获得物质赏赐。尤其对少数族人的客,北魏国家实行赐婚的做法。因为北魏赐客制的实行,使客阶层与拓跋鲜卑统治者建立起牢固的君臣关系,并在“归国”群体中占据主导地位,因而,也就促使“归国”群体的独立性逐渐泯灭。而且,随着孝文帝汉化措施的推行,使代人与汉人的交融不断深化,从而在社会、文化价值观的取向上日趋一致,因此,北魏实施的赐客制对促进北方民族交融,无疑产生了重要影响与推动作用。

铸牢中华民族共同体意识视域下粤北民族古籍研究——基于契约文书的考察

契约文书不仅是粤北地区民族经济活动的直接记录,也是粤北各民族交往交流交融的估证材料。以粤北地区民族古籍中的契约文书作为研究对象,从铸牢中华民族共同体意识视角出发,分析契约文书中所体现的粤北各民族经济往来、法律制度、民族交往、社会变迁等方面信息,以及在形式上集中展现的具有多文风、多语种、多载体特点,从不同的视角和层面客观地载录了中华文化在粤北的形成和发展过程。

戎与狄--西北地区东周戎狄遗存的探索历程与思考

西北地区的东周戎狄族群,在文献与考古学遗存上都表现出“西戎”与“北狄”的双重特征。21世纪前,“寺洼文化—毛家坪B组遗存”序列与甘宁地区的北方系遗存都被认为是东周西戎,但三者间的关系尚不清楚。21世纪以来,伴随新发现的推进,学界针对三种遗存与东周西戎的关系提出多种认识,其中虽有共识,但仍存在关键分歧。西北地区的东周戎狄遗存应打破单一分类,充实材料,扩大视野,以多元视角阐释遗存与人群的多样性。

北疆多民族生态文化融合与共生

中华优秀传统文化自古以来蕴含着丰富的生态文明思想,是人与自然和谐共生的文化根基。“天人合一”“道法自然”是我国先民构建人与自然和谐共生关系的价值理念和实践准则。我国北疆各民族在认识自然、适应自然、利用自然的漫长历程中创造了绚丽多彩的生态文化,是中华优秀传统文化的重要组成部分。蒙古族“游而牧之”的草原畜牧文化、鄂伦春族和鄂温克族“逐鸟兽而居”的狩猎采集文化、达斡尔族“顺天时,量地利”的农牧渔猎多元文化都有共同的指向,即“人与自然和谐共生”,为环境保护和生态治理提供了本土智慧。在中国式现代化推进中华民族伟大复兴的历史征程中,以各民族生态文化认同铸牢中华民族共同体意识,以各民族生态文化的交融共生筑牢北疆生态安全屏障,是北疆各民族人与自然和谐共生的文化方略。

河北张三营碱长花岗岩铌铁矿族矿物特征及其意义

张三营碱长花岗岩位于华北克拉通北缘,岩体具高分异特征,整体富铌,具有一定的成矿潜力。为查明其含铌矿物种类及岩浆演化过程,本文对岩体中铌铁矿族矿物开展了显微结构和矿物化学研究。结果表明:铌铁矿族矿物是碱长花岗岩中最主要的含铌矿物,化学成分富铌(Nb)、贫钽(Ta),以铌铁矿为主,少量为铌锰矿,按成因分为岩浆期和岩浆—热液期两类。岩浆期铌铁矿族矿物数量多,矿物多自形且具振荡环带结构,推测结晶于岩浆过程;背散射电子图像中少量岩浆期铌铁矿族矿物出现“亮边”结构和成分反环带,暗示矿物受熔体交代作用影响。岩浆—热液期铌铁矿族矿物含量较少,化学成分均匀,Mn^(#)和Ta^(#)值相对较高,是从熔体中快速沉淀形成的。张三营碱长花岗岩岩浆演化经历了岩浆冷凝期、岩浆—热液过渡期和热液期。岩浆冷凝期历时较长,是岩体富铌的关键,岩浆—热液过渡期熔体对铌、钽富集起到一定的作用,热液期流体交代作用较弱,影响有限。

粤北地区脑卒中高危人群筛查和干预项目患者满意度的影响因素分析

目的:分析粤北地区脑卒中高危人群筛查和干预项目患者满意度的影响因素,为粤北地区脑卒中高危人群筛查和干预工作提供理论指导。方法:通过问卷方式对粤北地区接受脑卒中高危人群筛查和干预的305例患者进行满意度调查,时间范围为2022年1月至2023年12月,主要内容包括患者基本情况、满意度评价内容。分析患者满意度分布情况,后采用多因素logistic回归模型分析患者满意度的影响因素。结果:305例患者中,满意组47例(18.22%),不满意组258例(81.78%)。两组患者在危害认知、医护人员态度、就医流程、住院健康教育方式、住院健康教育内容、就医环境、出院教育方式、出院教育内容、就医费用、随访方式、随访次数、复查的满意度方面比较,差异均具有统计学意义(P<0.05)。多因素logistic回归分析结果显示,对危害认知低(OR=4.677,P=0.004)、对就医费用不满意(OR=3.673,P=0.009)是患者满意度的独立危险因素。结论:应充分关注患者对当前脑卒中高危人群筛查和干预项目满意度的影响因素,以危害认知、就医费用为发展导向,健全脑卒中高危人群筛查和干预项目服务体系,满足患者的诊疗服务。

拉萨北部旁多群坠石沉积的发现及其意义

报道了新发现的旁多群中部的打鲁雄剖面及其含有典型坠石的沉积特征。该剖面旁多群中部以陆源碎屑少、悬浮泥质沉积为主的欠补偿的深水盆地相沉积为特征,同时夹有水下冰碛岩、重力流沉积等。纹层状—薄层状的粘土质岩层内分布着粒径是基质的100～1000倍的棱角状—次棱角状、长轴垂直近垂直于纹层面或层面的碎屑和砾石。砾石上下的泥质岩具有顶凸下挠的现象。碎屑和砾石及其对上下地层的影响表明其为坠石沉积。旁多群中指示冰川、冰筏沉积作用存在的坠石的发现,有力地证明了青藏高原石炭纪—二叠纪冈瓦纳相地层形成于受到冈瓦纳大陆冰川影响的海相环境。

冀北赤城红旗营子群中变质橄榄岩的岩石学与地球化学特征

冀北赤城红旗营子群中变质橄榄岩呈透镜状或团块状产于黑云斜长片麻岩之中，通过对其进行详细的岩石学和地球化学研究，结果显示：岩石类型为强烈蛇纹石化的方辉橄榄岩，具粒状变晶结构或鬣刺结构，变质橄榄岩富ω（MgO）（37．49％～38．91％），贫ω（CaO）（0．12％～1．17％），ω（Al2O3）（0．54％～1．54％）和ω（FeO^＊）（5．51％～9．06％），W（Ti02）介于0．01％～0．04％之间，REE含量低于原始地幔，过渡金属元素表现为不对称的“W”型配分型式，在Ti和Cu处形成明显的负异常“谷”。上述特征表明变质橄榄岩相当于SSZ型地幔橄榄岩，可能来自于消减带之下的上地幔，属于部分熔融程度很高的亏损地幔岩，因构造侵位而分布于红旗营子群之中，部分岩块则经历了俯冲-消减作用而形成鬣刺结构。

北秦岭二郎坪群重晶石岩热水沉积地球化学证据及其成矿意义

北秦岭二郎坪群中存在与地层整合产出的层状重晶石岩和铜多金属矿床。重晶石岩贫Al2O3、TiO2组分含量;富集热液组分As、Sb、Ba、Ag和Hg;微量元素U/Th>1;低ΣREE(平均值27.78×10-6)、富集轻稀土(LREE)、亏损重稀土(HREE)、具明显Eu正异常、Ce负异常及与大西洋TAG热液区热液沉积物相似的球粒陨石标准化的稀土元素配分模式特征。这些特征揭示研究区重晶石岩是热水沉积成因型。热水沉积重晶石岩与铜多金属矿床的紧密联系说明,研究区铜金属矿床是海底热液喷流沉积成岩成矿作用的产物。

广东南雄盆地的“南雄层”和“丹霞层”

本文沿用263地质队资料,将南雄红层底部出现的第Ⅰ沉积旋回划为松山组;重新厘定了南雄群的含义,阐明其间各岩石地层单位顶、底界线标志;沿用罗佛寨群;指出不必用丹霞群(组)表示南雄盆地边缘相的粗碎屑岩层,并认为丹霞盆地的丹霞组相当于南雄盆地的园圃组下段,建议南雄盆地弃用丹霞群(组)一名。在此基础上提出,粤北地区白垩系—古近系岩石地层序列是由松山组,南雄群(园圃组、主田组、浈水组),罗佛寨群(上湖组、浓山组、古城村组)组成。

羌北地块中—晚侏罗世雁石坪群古地磁新结果

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