Analysis on Characteristics of Seismic Damage of the Nepal M_S8.1 Earthquake in the Tibet Area of China

On April 25,2015,a M_S8. 1 earthquake occurred in Nepal. In the Tibet area of China,this earthquake caused heavy casualties and damage to housing,roads,communications,other lifeline engineering, water conservancy and other infrastructure. This paper introduces the basic situation of the earthquake,and based on the investigation and assessment of seismic intensity,the damage of the disaster area is analyzed,and building types and damage to the lifeline systems and various industries are given. Through the analysis of the characteristics of the earthquake disaster,this paper points out the existing problems in seismic fortification,and finally puts forward proposals for the prevention and control of earthquake geological disasters, scientific planning for the restoration and reconstruction,strengthening earthquake prevention and disaster reduction propaganda,improving the awareness of earthquake preparedness in the agricultural and pastoral areas,strengthening the guidance and supervision of housing construction in rural areas to reduce the casualties and losses,and promoting the harmonious development of economy in Tibet.

Geochemical Characteristics of Cenozoic Basaltic High-K Volcanic Rocks from Maguan Area, Eastern Tibet

The major element, trace element and Nd-Sr isotopic composition of Cenozoic basaltic volcanic rocks from the Maguan area, eastern Tibet, indicates that the volcanic rocks are enriched in alkalis, especially K (K-2O up to {3.81%}) and depleted in Ti (TiO-2={1.27%}-{2.00%}). These rocks may be classified as two groups, based on their Mg+# numbers: one may represent primary magma (Mg+# numbers from 68 to 69), and the other, the evolved magma (Mg+# numbers from 49 to 57). Their REE contents are very high (∑REE={155.06}-{239.04}μg/g). Their REE distribution patterns are of the right-inclined type, characterized by LREE enrichment [(La/Yb)-N={12.0}-{19.2}], no Ce anomaly (Ce/Ce+*={1.0}), and weak negative Eu anomaly (Eu/Eu+*={0.9}). The rocks are highly enriched in Rb, Sr and Ba ({59.5}-{93.8} μg/g, 732-999 μg/g, and 450-632 μg/g, respectively), high in U and Th ({1.59}-{2.31} μg/g and {4.73}-{8.16} μg/g, respectively), and high in Nb, Ta, Zr and Hf (70-118 μg/g, {3.72}-{5.93} μg/g, 215-381 μg/g, and {5.47}-{9.03} μg/g, respectively). In the primitive mantle-normalized incompatible element spidergram, Nb, Ta, Zr, Hf and P show positive anomalies, whereas Ba, Ti and Y show negative anomalies. The {{}+{87}Sr/+{86}Sr} ratios range from {0.704029} to {0.704761}; {{}+{143}Nd/+{144}Nd} from {0.512769} to {0.512949}; and εNd from {+2.6} to {+6.1}. These geochemical features might suggest that the potential source of the basaltic high-K volcanic rocks in the Maguan area is similar to the OIB-source mantle of Hawaii and Kergeulen volcanic rocks.

Phanerozoic Paleomagnetism Characteristics of the Qomolangma Area in Tibet

This paper conducts systematic test research on the 2920 paleomagnetic directional samples taken from Ordovician-Paleogene sedimentary formation in the north slope of Qomolangma in south of Tibet and obtains the primary remanent magnetization component and counts the new data of paleomagnetism the times. Based on the characteristic remanent magnetization component, it calculates the geomagnetic pole position and latitude value of Himalaya block in Ordovician- Paleogene. According to the new data of paleomagnetism, it draws the palaeomagnetic polar wander curve and palaeolatitude change curve of the north slope of Qomolangma in Ordovician-Paleogene. It also makes a preliminary discussion to the structure evolution history and relative movement of Himalaya bloc. The research results show that many clockwise rotation movements had occurred to the Himalaya block in northern slope of Qomolangmain the process of northward drifting in the phanerozoic eon. In Ordovician-late Cretaceous, there the movement of about 20.0~ clockwise rotation occurred in the process of northward drifting. However, 0.4° counterclockwise rotation occurred from the end of late Devonian epoch to the beginning of early carboniferous epoch; 6.0° and 8.0° counterclockwise rotation occurred in carboniferous period and early Triassic epoch respectively, which might be related with the tension crack of continental rift valley from late Devonian period to the beginning of early carboniferous epoch, carboniferous period and early Triassic epoch. From the Eocene epoch to Pliocene epoch, the Himalaya block generated about 28.0° clockwise while drifting northward with a relatively rapid speed. This was the result that since the Eocene epoch, due to the continuous expansion of mid-ocean ridge of the India Ocean, the neo-Tethys with the Yarlung Zangbo River as the main ocean basin closed to form orogenic movement and the strong continent-continent collision orogenic movement of the east and west Himalayas generated clockwise movement in the mid- Himalaya area. According to the calculation of palaeolatitude data, the Himalaya continent- continent collusion orogenic movement since the Eocene epoch caused the crustal structure in Indian Plate- Himalaya folded structural belt- Lhasa block to shorten by at least 1000 km. The systematic research on the paleomagnetism of Qomolangma area in the phanerozoic eon provides a scientific basis to further research the evolution of Gondwanaland, formation and extinction history of paleo- Tethys Ocean and uplift mechanism of the Qinghai-Tibet Plateau.

Characteristics of Metamorphic Rock Magnetic Fabrics in the Nyalam Area of the Southern Tibet and Its Geological Significance, China

This paper reports Precambrian rock magnetic fabrics in the Nyalam area of southern Tibet. The analytical results of magnetic fabrics show that the values of H are high （〉 10% in general）, so the ductile deformations of the Precambrian rock are strong. The orientation of the maximum principal stress inferred from the minimum magnetic susceptibility is nearly S-N, NE-SW and NW-SE. The Flinn diagram of the magnetic fabrics show that the strain pattern is oblate and constrictional type. Magnetic foliation of great majority of rock samples is well developed and the magnetic lineation is poor and the magnetic susceptibility ellipsoid is flattened. The magnetic lineation of the minority rock samples is well developed and the magnetic foliation is poor and the magnetic susceptibility ellipsoid is prolate. According to the geological field and the magnetic fabrics, there are 3 times tectonic stress field in SN directed extruding, NW-SE directed extruding, NW-SE directed extension. It shows that the Nyalam area has undergone process the orientation of SN, NW-SE nappe structure and NW-SE directed extension structure. The change of tectonic stress is reflected by the field characteristics of the Precambrian rock magnetic fabrics that is the direct responding result of the arc-continental, continent-continental collision between the India and Asian continents in the late part of the Late Cretaceous to Late Eocene and subsequently shifted to intra-continental convergent, the plateau uplifting and extension structure stage since the Late Eocene.

THE GEOCHEMISTRY CHARACTERISTICS OF BLUESCHIST IN THE GANGMAR AREA, QIANGTANG BLOCK, TIBET

The Qinghai—Xizang (Tibet) Plateau was assembled by the successive accretion of continental and arc terranes to Asia during the Palaeozoic, Mesozoic and early Tertiary. From north to south, the Plateau was divided into four terranes (from north to south): Songpan\|Garze, Qingtang, Lhasa and India terranes. The Qiangtang terrane was divided into two parts by Chabu\|Shuanghu suture: Northern Qiangtang and Southern Qiangtang blocks. It was believed that there is a suture as Palaeotethyan suture between the two blocks from Lungmu lake to Chabu, to Shuanghu, to Langcangjiang, but some geologists opposited this opinion, such as Wang Chengshan et al.(1987) and Deng Wanming et al.(1996). The blueschists that bear the typical glaucophane were found in the Gangmar Area in summer of 1997. The blueschists consist of glaucophane, crossite, phengite, actinolite, epidote, sphene ,rutile, and so on. Blueschists show nappe structures in enclosing rocks, and thrust over Tertiary from north to south.The age of blueschist is 275～285Ma which stand for the metamorphic age of blueschist. The geochemical contents of blueschists are the following: SiO\-2 is 45 37%～53 82%, Na 2O>K 2O, K 2O+Na 2O are 3 72%～7 61%, Na 2O/K 2O is 1 70～19 67, MnO is 0 16%～0 22%, FeO+Fe 2O 3 are 11 12%～14 27%, TiO 2 is 2 34%～4 28%, P 2O 5 is 0 34%～1 03%. From the contents, SiO 2 is inverse relation with K 2O+Na 2O, K 2O and FeO+Fe 2O 3. In the SiO 2\|K 2O+Na 2O diagram, the blueschists fall in the field of Alkali basalt; in the TiO 2\|MnO(10\|P 2O 5×10 triangular diagram, these plot within the Ocean Island Basalts(OIB) field. The whole REE content is (117 03～390 97)×10 -6 , LREE/HREE is 5 05～9 80, the REE diagram shows the feature that LREE is rich and HREE is depleted, this is similar to the OIB. In the spidergram of trace elements show the same characterristics as the OIB. Meanwhile, the trace elements ratios, such as Ba/Nb, La/Nb, Nb/Th, Nb/Y, Zr/Y, Zr/Nb, Hf/Sm, Ta/Hf, Nb/Ta, Nb/U, suggest the tectonic setting is OIB. On the basis of these materials, the blueschists are akin to within\|plate ocean island basalts. This shows that there is a ocean or oceanic basin in the Chabu\|Shuanghu belts and the formation of blueschists is the quicky subduction of the Ocean Island Basalts in Early Permian between the Gondwana and Eurasia continents. It demonstrated, therefore, that the Chabu\|Suanghu suture exists and may extend to the east to Lnagchangjiang, and may extend into Thailand\|Malaysia Peninsula.

The Major Two-stage Shortening Deformation of the Northern Tibet and Tian Shan Area Since the Latest Oligocene

It seems to be progressively recognized that the stress of the India-Asia convergent front can be transferred rapidly through the southern and central Tibetan lithosphere to the northern Tibet, hence leading to the crustal thickening deformation there during or immediately after the onset of the India-Asia collision（ca.55 Ma）.This study focuses on the late Cenozoic deformation and tectonic uplift of the northern Tibet and Tian Shan area.Detailed compilations of a variety of proxy data from sediments and bedrocks suggest that the northern Tibet and Tian Shan area underwent one stage of approximately synchronous widespread contractile deformation since 25–20 Ma, which seemed to decrease at circa 18 Ma as revealed by low-temperature thermochronological data.The latest Oligocene-early Miocene was also significant basin-forming episodes when many intermontane subbasins began to receive syntectonic sedimentation in the northeastern Tibet.Subsequently, the other phase of compressional deformation began to encroach more widely into the northern Tibet and Tian Shan area in episodic steps or continuously from 16–12 Ma to present.

Deep-derived enclaves (belonging to middle-lower crust metamorphic rocks) in the Liuhe-Xiangduo area, eastern Tibet: Evidence from petrogeochemistry

Petrological and geochemical studies of deep-derived enclaves from the Liuhe-Xiangduo area, eastern Tibet, showed that the enclaves involve five types of rocks, i.e., garnet diopsidite, garnet amphibolite, garnet hornblendite, amphibolite and hornblendite, whose main mineral assemblages are Grt+Di+Hbl, Grt+Pl+Hbl+Di, Grt+Hbl+Pl, Pl+Hbl, and Hbl+Bt, respectively. The enclaves exhibit typical crystalloblastic texture, and growth zones are well developed in garnet (Grt) in the enclaves. In view of major element geochemistry, the deep|derived enclaves are characterized by high MgO and FeO+*, ranging from {12.00%} to {12.30%} and {8.15%} to {10.94%}, respectively. The protolith restoration of metamorphic rocks revealed that the enclaves belong to ortho-metamorphic rocks. The REE abundances vary over a wide range, and ∑REE ranges from {53.39} to {129.04} μg/g. The REE patterns slightly incline toward the HREE side with weak LREE enrichment. The contents of Rb, Sr, and Ba range from {8.34} to 101μg/g, 165 to 1485 μg/g, and 105 to 721 μg/g, respectively. The primitive mantle-normalized spider diagrams of trace elements show obvious negative Nb, Ta, Zr and Hf anomalies. Sr-Nd isotopic compositions of the enclaves indicated that the potential source of deep-derived enclaves is similar to the depleted|mantle, and their {({}+{87}Sr/+{86}Sr)-i} ratios vary from {0.706314} to {0.707198}, {({}+{147}Nd/+{144}Nd)-i} ratios from {0.512947} to {0.513046}, and {ε-{Nd}(T)} values from {+7.0} to {+9.0}, respectively. The potential source of the enclaves is obviously different from the EM2-type mantle from which high-K igneous rocks stemmed (the host rocks), i.e., there is no direct genetic relationship between the enclaves and the host rocks. Deep-derived enclaves in the host rocks belong to mafic xenoliths, and those in the Liuhe-Xiangduo area, eastern Tibet, are some middle-lower crust ortho-metamorphic rocks which were accidentally captured at 20-50 km level by rapidly entrained high-temperature high-K magma, whose source is considered to be located at 50-km depth or so.

Confinement and Semi-confinement Raising Fattening Technology of Yaks in Agricultural Areas of Tibet

In the study, confinement and semi-confinement raising fattening technology of yaks in agricultural areas of tibet were analyzed. And several suggestions for improving the efficiency of yak raising were put forward. Aiming at providing the reference of healthy raising and sustainable development of yaks in the agricul- tural areas of tibet.

Land Use Change and Its Effect on Environment Based on Farmers’Behaviors: A Case Study in Agricultural Areas of Tibet, China

In the case study in Agricultural Area of Tibet, the process and characteristics of farmers' land use were surveyed by semi-structural interview questionnaire. By comparing the change of land covers and farmers' land decision in two periods, the spatial connection of them was obtained. And the relations among farmers' land decision, land use change and environment were examined by calculating emergy and value flow. The results show that: hunting the maximal profits is the primary aim of farmers' land decision; farmers' land decision is incompatible with sustainable land use presently; farmers' land decision and land cover can be embodied spatially by each other; the change of farmers' land decision can be monitored by observing the change of land cover, and the sustainability of farmers' land decision can be appraised by calculating emergy and value flow.

Revision of the Genus Conophyllia d'Orbigny 1849(Anthozoa, Scleractinia, Triassic) and Conophyllia from the Renacuo area of Gêrzê, Tibet

There have been divergent opinions on whether Conophyllia develops synapticulae and dissepiments since its erection in 1849, with different views existing on the morphology of columella in Conophyllia.This paper presents a comprehensive review of Conophyllia, and revises the diagnosis according to new material from the Renacuo area of Gêrzê, Tibet.The revised diagnosis emphasises the following features： solitary coral; abundant radial elements subequal in thickness, lateral faces with granules and synapticulae; parietal, papillar or incompact columella, a few species lacking in columella; developed dissepiments.Individuals of Conophyllia have laminar septa of Triadophyllum type in earlier ontogenetic stages, while their septa in later ontogenetic stages are more fenestrate.The geological and geographical distribution of this genus is discussed, with five species of Conophylliafrom the Renacuo area of Gêrzê, Tibet being described and illustrated, including one new species and two in open nomenclatue.

Richly Endowed Qamdo Area In East Tibet

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Petrogenesis and Tectonics of the Naruo Porphyry Cu(Au) Deposit Related Intrusion in the Duolong Area,Central Tibet

The Duolong area is the most important part of the Western Bangong-Nujiang Suture Zone porphyry Cu（Au） metallogenic belt, in Tibet, China. Here new detailed data are presented from LAICP-MS zircon U-Pb, whole-rock geochemical, and in-situ zircon Hf isotope analyses for igneous rocks in the large Naruo deposit（2.51 Mt of Cu and 82 t of Au） which is located ~2 km NE of the Duolong（Duobuza and Bolong） super-large gold-rich porphyry copper deposit. We integrated our results with previous research of other porphyry deposits in the Duolong area and have identified the timing, geodynamic setting, and petrogenesis of the mineralization-associated magmatic events. Based on the measurements, the Duolong area porphyry Cu（Au） deposit formations are associated with Early Cretaceous intermediate-felsic magmatism, which is consistent with U-Pb zircon ages of 120 Ma. All the main intrusive rocks in the ore-concentrated area have similar lithogeochemical characteristics; they show a relative enrichment in both light rare earth elements（LREEs） and large-ion lithophile elements（LILEs： Rb, Ba, K, etc.） and relative depletion in both heavy rare earth elements（HREEs） and high field strength elements（HFSEs： Nb, Ta, Zr, Hf, etc.）. Moreover, the granite porphyry shows positive εHf（t） values between 1.38–7.37 suggesting that magmas were potentially derived from the partial melting of a depleted mantle wedge that had been metasomatized by subducted slab-derived fluids or melts. This paper points out that the formation of the porphyry-epithermal Cu（Au） deposit in the Duolong area was dominated by northward subduction of the Bangongco Tethys Plate beneath the Qiangtang block in the Early Cretaceous（124–114 Ma）, when the subducted oceanic crust reached 50–70 km underground and generated different degrees of phase transformation, which lead to a melt produced by dehydration of amphibole minerals, a metasomatized mantle wedge, and induced mantle partial melting that produced the magma. Those deposits occurred in a continental arc tectonic setting, which is similar to the continental margin arc environment of the ocean-continent subduction setting of the Andes metallogenic belt in South America.

THE LAST TRADE CARAVAN IN TIBET WANGCHEN WAS BUSY IN AN AGRICULTURAL AREA

Setting off from Lhasa we followed Lhasa River,passing through Chushur County,then,driving along the banks of the Yarlung Tsangpo River,we finally arrived at Nyemo Bridge.Next we headed northward and into a long valley.Finally,we reached Nyemo County.Although it was not a big county,it looked much more prosperous than Palgon County.A large government office building greeted us in a main street offering shops,both big and small,as well as restaurants-which also caught our eye.Nevertheless,the wandering la...

PIRLS视域下甘青涉藏州县四年级学生阅读素养调查

利用PIRLS测评框架,对甘肃和青海涉藏州县500名四年级学生的阅读素养现状及其影响因素进行了测试和分析。研究发现,绝大多数学生的阅读素养水平处于中等偏下水平,而学生的阅读态度、阅读目的与习惯、教师的阅读指导策略、家庭语言环境以及文化资源等因素对学生阅读素养具有重要影响。据此提出:在宏观层面上制定有针对性的政策、中观层面上设计多元化的课程、微观层面上优化阅读教学,不同层面的支持网络相互协作,共同推动民族地区小学生阅读素养的全面提升。

基于SWOT卫星模拟数据的青藏高原湖泊水位与面积测量精度评估

青藏高原作为“亚洲水塔”,密集分布着众多高山湖泊,其湖泊数量与面积约占我国湖泊的一半。青藏高原湖泊作为气候与环境的“指示剂”,在时间序列上监测这些湖泊的水位与水量变化至关重要。2022年12月发射的地表水与海洋地形(SWOT)卫星将以前所未有的高时间分辨率和面状测高模式监测近乎全球的地表水动态。在数据正式向科学界公开前,有必要对SWOT卫星的性能及测量精度进行评估。本文使用SWOT卫星模拟观测生成器,实现了青藏高原部分湖泊水位与面积的模拟观测,并结合水位计数据,对SWOT卫星在时间失真、测高误差和面积误差方面的测量精度评估。结果表明,不同数据采集间隔的时间失真平均百分比误差小于4.1%,测高误差平均小于3 cm,面积误差小于湖泊面积的7%。该研究的开展为SWOT卫星在青藏高原湖泊上的应用奠定了基础,将更好地理解未来湖泊变化对气候变化的响应。

特提斯喜马拉雅带东部陆热地区火山岩年代学、地球化学及成因研究

本文首次开展了对特提斯喜马拉雅带东部陆热地区的中酸性火山岩进行了系统的锆石LA-ICP-MS U-Pb年代学、全岩主元素、微量元素研究,结果表明:陆热地区酸性火山岩主要为英安岩和流纹岩,样品锆石U-Pb定年获得了141.1 Ma±1.3 Ma、135.3 Ma±6.6 Ma两个年龄值;稀土元素分配图呈明显的右倾模式,轻重稀土分馏明显,Eu负异常;在微量元素原始地幔标准化蛛网图中,样品富集大离子亲石元素(LILE),亏损Nb、Ta、Ti等高场强元素(HFSE),显示出壳源岩浆的特征。陆热地区中性火山岩为安山岩,样品锆石的U-Pb年龄为133.9 Ma±4.9 Ma,样品稀土元素分配图呈明显的右倾型模式,且没有明显的Eu异常。在微量元素原始地幔标准化蛛网图中,样品无Nb、Ta负异常,且其Mg^(#)值较高(42.9),相容性元素Ni、Co、Cr、V等含量相对较高,显示出一定的幔源岩浆特征。本研究认为,陆热地区酸性火成岩是在地壳伸展减薄的拉伸环境以及Kerguelen地幔柱活动的双重作用下,幔源岩浆底侵使上地壳发生部分熔融形成;中性火成岩则是与Kerguelen地幔柱活动有关的基性岩浆经历了一定程度的分离结晶,并沿着构造裂缝上涌喷出形成。

藏西北多龙矿集区拿若斑岩铜(金)矿床磷灰石矿物学特征及地质意义

拿若矿床目前是藏西北改则县多龙矿集区第三大斑岩型铜(金)矿床,前人开展了系统的成岩成矿年代学、成矿地质背景等研究,但空间蚀变分带和岩浆演化过程等方面研究较为薄弱。笔者等以拿若矿床磷灰石作为研究对象,在大量钻孔科研编录的基础上,开展了磷灰石矿物学和矿物化学研究,探讨拿若矿床磷灰石矿物彩色阴极发光特征与蚀变分带的耦合关系,揭示含矿岩浆演化期次及氧化还原状态。磷灰石彩色阴极发光特征显示,拿若矿床磷灰石彩色阴极发光(CL)特征主要表现为黄褐色、绿色—亮黄色和灰黑色,分别对应未蚀变、钾化蚀变和绢英岩化蚀变环境,磷灰石彩色CL特征与其所处蚀变环境的关系验证了笔者等重新厘定的拿若矿床斑岩系统“双钾化带”空间蚀变分带结构。磷灰石电子探针(EPMA)主量元素测试结果显示,磷灰石的CaO=53.5%~56.5%,P_(2)O_(5)=39.5%~42%,F=1.26%~3.24%,Cl=0.01%~1.99%,SO_(3)=0~1.28%,由此计算的X_(F)=0.68~1.76,XCl=0.001~0.58,X_(OH)=0.21~1.05。不同类型、阶段的磷灰石挥发分(F、Cl、OH)、SO_(3)等成分含量变化趋势反映了拿若矿床岩浆—热液演化过程发生了气体饱和→流体出溶→金属沉淀的过程,并揭示了成矿岩浆高氧逸度的性质。此外,环带状岩浆磷灰石反映了隐爆角砾岩系统发育了三期次岩浆作用,并指示了第I、III期岩浆活动具有更高氧逸度特征,与成矿关系更加密切。因此,笔者等认为在多期次岩浆热液叠加型斑岩铜矿床中,磷灰石在辅助厘定蚀变类型和反演岩浆—热液演化过程中具有重要的价值。

青藏高原湖泊面积变化规律及影响要素分析

青藏高原是气候变化的敏感区域,在全球气候变暖的背景下,高原湖泊发生明显变化。本文利用基于青藏高原湖泊遥感数据,分析了1970s—2021年青藏高原大于1km^(2)的湖泊面积的时空变化特征。研究结果表明:(1)青藏高原的湖泊面积和数量均呈现先减少后增加的态势,1995年前大部分湖泊呈现萎缩状态,1995年之后青藏高原湖泊数量(16.5个/a)和面积(472km^(2)/a)都呈现增加趋势,并在2019年达到最大值。西藏湖泊数量增加远大于青海省湖泊数量的增加。不同面积湖泊中,(1,100]km^(2)湖泊数量增加最迅速,占总增加数量的77.2%。(2)青藏高原湖泊面积与气温的相关性(R=0.8213)要比与降水的相关性(R=0.5847)高。其中分区间研究表明,西藏湖泊面积与气温的相关性(R=0.8072)更好,这与青藏高原的变化规律一致。而青海省则不同,与降水的相关性较高(R=0.6791),可能是由于西藏地区冰川和多年冻土面积占比较大。

模糊逻辑模型在珠勒地区遥感找矿中的应用

近年来遥感技术在地质矿产勘察中发挥着重要作用,基于多源遥感数据对蚀变矿物的提取在工作中大大缩减了靶区范围和时间成本。基于Landsat-9、ASTER和Sentinel-2遥感数据开展西藏珠勒地区的矿物蚀变信息的增强与提取。通过线性隶属函数将多源遥感数据主成分分析(principal component analysis,PCA)中的特征分量归一化后采用Fuzzy Gamma算子进行叠加绘制找矿靶区。实验中γ参数的设置分别是0.7、0.75、0.8、0.85和0.9,最终经过试验测定γ=0.85效果相对较好。实验共圈定了8个靶区,通过野外调查验证了该方法在高海拔地区靶区圈定的可行性。同时,野外调查结果显示该地区发育高硫型浅成低温热液蚀变矿物组合,具有斑岩-浅成低温热液矿床的成矿潜力。