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Much attention has been paid to the Linzizong volcanic rocks which are extensively developed along the strike of southern and central Lhasa Terrane because these rocks are generally considered to document the history of late subduction of the Neo-Tethyan ocean lithosphere and subsequent India-Asia collision. However, reliable age data for the Linzizong volcanic in a regional scale rocks remain very insufficient. In this paper, the authors performed zircon U-Pb dating, zircon Hf isotope determination, and whole-rock element geochemical study of a volcanic breccia-bearing rhyolite sample collected from the Linzizong volcanic rocks in Milashan, eastern segment of the southern Lhasa Terrane. Eighteen analyses of zircons from this sample yielded a zircon 206Pb/238U age of 60.1±0.9Ma, coeval with the andesitic volcanism documented in the lowerest Dianzhong Formation in Linzhou Basin. This sample is characterized by significant depletion of middle rare earth element (MREE) and low abundances of heavy REE, with positive zircon εHf(t) values ranging from +8.5 to +18.8. Such geochemical characteristics indicate that this sample probably originated from partial melting of thick and juvenile lower crust materials under a transitional condition from amphibolite to eclogite facies. At present, it is still difficult to explore the tectonic implications of the differences in REE abundances observed from the ca.60Ma Linzizong volcanic rocks along the strike of the Lhasa Terrane.
The Shenjiayao gold deposit and its neighboring areas are mostly covered by Quaternary loess. Ore-control structures under loess cover can be effectively detected by such means as high resolution magnetic method, very Low frequency electromagnetic method, CO2 survey and Rn survey, which are all portable geophysical or geochemical methods. Anomalies in structures can be discovered by mobile metals survey method. The combination of these methods can be used in search for gold deposits in areas covered by loess.
Latin America is one of the regions that have richest mineral resources in the world. In this paper, the authors have summarized the metallogenic geological setting of this region, divided the metallogenic zones, and studied the metallogenic series so as to guide the further planning and development. In this paper, the tectonic contours of the earth were divided into three tectonic domains, with a discussion on the secondary tectonic zones. As for the division of metallogenic belts, the authors classified the zone into primary metallogenic domain and secondary metallogenic province according to the five-stage metallogenic zone scheme. For the metallogenic units of level 3 and under level 3, the authors made a brief comparison with previous results. In terms of metallogenic series, the authors took the tectonic evolution as the guidance and the mineralization and deposit types as the indicators, collaborated the deposits that have inner connection into one series, and then divided them into sub-class metallogenic series and metallogenic assemblages.
This paper emphatically describes the general situation, geological characteristics and genetic types of bauxite resources in Latin America. The bauxite resources of Latin American are mainly distributed in Brazil, Suriname, Jamaica, Guyana and Venezuela, and the reserves have reached 6.03 billion tons which account for 21.54% of the world's bauxite total reserves. Brazil is the largest bauxite producer and export country in Latin America. The genetic types of Latin American bauxite include lateritic type and karst type. There are 45 major bauxite mines in Latin America. The Jamaica island arc, Guyana shield, middle Brazil shield and San Francisco shield are the major bauxite resources potential areas for exploration and development in Latin America.
Located across Indo-Australian plate, Pacific plate and Eurasian plate, Oceania has undergone long and complex tectonic evolution since Archean. Three major tectonic units can be identified according to the regional geology of this region, i.e., middle-western Australian Precambrian craton, eastern Paleozoic orogenic belt and Circum-Pacific Meso-Cenozoic island arcs. Theses three major tectonic units could be subdivided into twelfth second-order tectonic units and forty third-order tectonic units. The three major tectonic units exhibit different types of rock assemblage and mineralization due to the unique tectonic evolution history of each unit. Mineralization characteristics of the three major tectonic elements are summarized on the basis of a comprehensive analysis of the relationship between the tectonic evolution and the mineralization events: the mineralization of the middle-western Australian Precambrian craton mainly took place in Archean and Proterozoic, with the dominant mineral resources being gold, copper, nickel, manganese, iron, uranium, REE, lead-zinc bauxite, which were associated with the development of Australian Precambrian craton; the mineralization of the eastern Paleozoic orogenic belt mainly occurred in Paleozoic, and dominant mineral resources were copper, gold, lead-zinc, tungsten and tin, which were associated with the interaction between Palaeo-Pacific and Australia; the mineralization of the Circum-Pacific Meso-Cenozoic island arcs mainly occurred in Miocene-Pleistocene, and the dominant mineral resources produced included copper, gold, nickel and cobalt, which were related to the interaction between Indo-Australian plate, Pacific plate and Eurasian plate. An overall assessment shows that Oceania has very good iron, manganese, copper, gold, bauxite, uranium, nickel and REE resource potentials.
Controversy has long existed over the ages of Jurassic strata in Chengde basin，northern Hebei. The authors obtained for the first time the U-Pb age (163.4Ma±1.1Ma) of zircon from tuff of the Jiulongshan Formation. In combination with ages of other Jurassic strata, the authors hold that the age of the Jiulongshan Formation is most likely in the range of 159~165Ma, suggesting an epoch between late Middle Jurassic and early Late Jurassic. This result indicates that the Jiulongshan Formation should belong to Callovian-Oxfordian period. Petrochemical and geochemical analyses show that the tuff is of peraluminous, K-high, and calc-alkaline nature, with A/CNK being 6.31~16.22. The ∑REE values range from 190.96×10-6 to 340.68×10-6, and the REE patterns show right-oblique feature and obvious negative Eu, Sr anomalies. Trace elements show enrichment of LILE (large ion lithophile elements) such as Rb, Ba, Th and U and depletion of HFSE (high field strength elements) such as Nb, Ta and Zr. The REE distribution patterns and trace elements characteristics of tuff in Jiulongshan is similar to those of the upper crust which had been partially melted by greywacke.
Based on a study of the characteristics of Carboniferous-Permian basin basement structure, lithostratigraphy, sedimentary evolution and planar sedimentary facies, the authors consider that the Carboniferous-Permian basin of Ejin Banner and its vicinities is a uniform rift basin: there existed onlap sedimentation from north to south during Early Carboniferous-early Early Permian period and onlap sedimentation from south to north at the middle stage of Early Permian- Early Permian period, and the basin evolution reached its climax in Amushan stage of Late Carboniferous- Early Permian period, with the sediments being mainly of shallow sea shelf facies. Based on a study of the distribution of hydrocarbon source rocks, organic matter abundance, kerogen type and hydrocarbon source rock evolution, it is considered that widespread shallow sea- continental shelf argillutite has good conditions for hydrocarbon generation. There are several sets of hydrocarbon source rocks characterized by large thickness, middle-higher content of TOC and II type kerogen. The evolution has mainly been affected by burial history, and the hydrocarbon source rocks are of the mature-high mature stage. Controlled by thermal contact of Yanshanian intrusive rock and tectonic dynamometamorphism in the strongly tectonic reworking belt, the hydrocarbon source rocks of the northern study area was once reached the mature stage.
Optically Stimulated Luminescence (OSL) method dates the last bleached or thermal event of the sediments. Since its development in the 1980s, OSL dating has been improved significantly. Quartz and feldspar are mainly applied to conduct such dating. This paper aims to provide an overview of the OSL dating method for geoscientists who intend to use OSL dating for chronological control in which the sampling in the field can satisfy OSL chronologists. The general principles of the method are described, and the procedures of OSL dating from the field sampling to the age interpretation in the luminescence dating laboratory are recounted, which include sampling, pretreatment, equivalent dose (De) and dose rate determination. Recent methodical and technological progress and the development of new laboratory measurement procedures for obtaining the De have resulted in more widespread and more confident use of OSL for dating, and new luminescence signals are being investigated in order to extend the age range back by an order of magnitude from 100ka to 1Ma.
This paper mainly deals with new progresses that have been made in the map compilation of Oceania. The research party has compiled The Geological Map of Oceania region (1:2500000) and The Metallic Mineral Map of Oceania (1:2500000). In the manual of the map, the authors re-divided the original three primary tectonic units of Oceania into four primary tectonic units, highlighted the importance of Mesozoic tectonic units in the Papua New Guinea-New Zealand orogenic system, and separated them from the Cenozoic tectonic unit of southwest Pacific island arc. The four primary tectonic units were redefined into 12 secondary tectonic units and 42 third-level units, and the corresponding stratigraphic column graphs and intrusive sequence diagrams were prepared. The tectonic evolution of Oceania was described in this paper. According to the metallogenic characteristics of corresponding mineralization belts, the Oceania region was divided into 4 metallogenic domains, i.e., the central-western Australia continental Precambrian cratonic metallogenic domain, the eastern Australia Paleozoic orogenic metallogenic domain, the Papua New Guinea-New Zealand Mesozoic island arc metallogenic domain and the southwestern Pacific Cenozoic archipelagic arc-basin system metallogenic domain. This paper also summarized the geological and mineral resource characteristics of each metallogenic belt.
The Suining-Jingzhou (Huitong)-Tianzhu-Xinhuang section of the central Mt.Xuefeng shows that the deformation of the central Mt.Xuefeng gets weaker from the east to the west, i.e. from the west-vergencing tight folds in the east to the open folds in the west. The deformation has affected the Nanhuan System and Sinian System-Lower Paleozoic strata in the eastern section (Suining-Jingzhou), and the style of folds indicates that there is a regional decollement between the Nanhuan System and the Banxi Group in the east. The shortening of the eastern section is about 11km. The deformation has affected the Banxi Group, Nanhua System and Lower Paleozoic strata in the western section (Jingzhou-Tianzhu-Xinhuang), the regional decollement mainly occurred in the lower part of the Banxi Group or between the Banxi Group and Lengjiaxi Group. The shortening of the western section is about 46km. The boundary between the western and the eastern sections is the normal fault controlling the early depositing of the Banxi Group and the Nanhuan System. This study has obtained the minimum shortening distance across the central Mt.Xuefeng, which is similar to previous data. This means that no large scale thrusting had ever occurred in the Mt.Xuefeng during the Paleozoic.The facts of the overlap unconformity between the Carboniferous and penetratively deformed Nanhuan Systems in the central Mt.Xuefeng, the tectonic attribute of the Jingzhou basin, and deformational style along the section indicated that the deformation of the Proterozoic and Lower Paleozoic strata in the central Mt.Xuefeng took place in Early Paleozoic. The Paleozoic deformation in the Mt.Xuefeng was the result of the inversion of the early rift, which belongs to thin-skinned structure.
The southern Tianshan collisional orogenic belt belongs to the middle-southern part of the Tianshan orogenic system in the southern North Asia area between the Siberia and Tarim blocks. It is situated between the Tarim and Kazakhstan-Junggar blocks, and geographically includes the Haerke, Erbin and Hula mountains. The orogen is mainly made up of Paleozoic terranes, which are represented by active continental margins at the southern and northern sides and relic oceanic crusts and accretionary complex (produced during evolution of the Paleozoic southern Tianshan Ocean) at the central region. It is proposed that the southern Tianshan oceanic basin came into being in Sinian through continental rifting, and continued to expand during Cambrian. From Ordovician to Carboniferous, the oceanic basin experienced subduction at both the northern and southern sides, leading to its final closure in late Carboniferous. From Permian to early Triassic, the southern Tianshan orogen experienced the stage of post-orogenic adjustments.
Mozambique, located in the southeast of Africa, is a vital country to strengthen the "One Belt And One Road" mining production capacity cooperation.Based on the study of the distribution of mineral resources and development status of important mines in Mozambique, the prospect of Chinese enterprises' mining investment in Mozambique is analyzed from the aspects of political stability and business environment.Mozambique's dominant oil and gas resources are mainly distributed in the Luvuma and Mozambique basins in the Sentoo-Rovuma-Zambezi-Maputo metallogenic belt, coal mainly in the Sentoo-Zambezi metallogenic belt, titanium-zirconium in the coastal area of the Sentoo-Rovuma-Zambezi-Maputo metallogenic belt, gold mainly in Niassa-Angónia- Zimbabwe metallogenic belt and Zimbabwe-Sentoo-Baruhe metallogenic belt, graphite in the Ancuabe and other areas of the Mozambique metallogenic belt, and tantalum and niobium in the Alto Ligonha area in the southern part of the Mozambique metallogenic belt.Mozambique is rich in mineral resources, especially oil, natural gas, coal, tantalum-niobium and heavy sand ore (titanium-zirconium) occupy an important position in the world.Although there are some unfavorable factors, such as backward infrastructure, lack of basic geological data and lengthy judicial procedures, it is believed that investors can start with heavy sand ore (titanium zirconium) and gold deposits with abundant resources and a good development basis; then targeting opportunities to invest in the development of petroleum, graphite, niobium tantalum and other minerals with greater potential; and at the same time, strengthen the international production capacity cooperation with local enterprises in Mozambique, promote local social and economic development, and jointly create a green and low-carbon development model.
Four typical intrusions, i.e., Yingmailai intrusion in the east part of the south Tianshan, Chuanwulu and Baleigong intrusions in the Kuokousaling regions and Mazashan intrusion in the northwest Tarim Basin, are chosen for petrological and geochemical investigations. These intrusions which come from three different regions have distinct geochemical characteristics. The Yingmailai intrusion consists of biotite granite and two-mica granite, which are characterized by high SiO2 contents, weak aluminium-oversaturated feature, high initial Sr isotopic ratios (around 0.710） and negative εNd(t) values（-4 to -6）. So it can be classified into S-A transitional type. The Mazashan intrusion is alkali, and composed of syenite, which is characterized by absence of significantly negative Nb and Ta anomalies on primitive mantle normalized trace element patterns. The Chuanwulu intrusion consists predominantly of syenite and monzonite. The systematic geochemical investigations suggest that the syenite and monzonite are formed by mixing of mafic magma with felsic magma in different ratios. Comparably, the Baleigong intrusion has similar geochemical features with granite porphyrite. In combination with petrological and geochemical characteristics, we suggest that the Yingmailai intrusion in the east part of the south Tianshan was produced by partial melting of "cool" thickened crust induced by radiogenic heating, whereas the felsic rocks were formed by partial melting of thin crust in response for underplating of mantle-derived mafic magma. In contrast, the Mazashan intrusion was formed in a different tectonic setting, which can be attributed to Permian large magmatic event in the Tarim basin. Consequently, the nature of the Permian magma is controlled by the compositions and structure of crust.
The similarity and difference between C -type adakitic rocks in eastern China and typical Adakite in the Pacific Ocean in respect to geochemistry and tectonic setting are discussed.Mesozoic inter-mediate-acid igneous rocks with adakitic signatures in eastern China are considered as the product of in-tracontinental magmatism.It is inferred that they originated by partial melting of basic rocks in the lower crust due to underplating of basaltic magma from the lithospheric mantle to the bottom of the thickened continental crust(>50km)with cratonic affinity.The geodynamic implications of Adakite,especially C-type Adakite,are dealt with in the paper.Adakite can be considered as a new series of island-arc magma-tism and its discovery marks a major breakthrough in the petrological study and initiates a new way for the study of granitoids rocks.Several possible tectonic settings for the formation of Adakite are also dis-cussed.Adakite is a key to the study of crustal thickening and relevant events in geological history and the backward deduction of the composition of the lower crust.In addition,the relation of Adakite to mineral-ization is also discussed.
The Karamaili faulting belt is well-known in the Northern Xinjiang and Central Asian area, and it came into being after the closure of the Paleozoic ocean. It has been a hot-debated issue on the ancient subduction polarity of the zone as well as whether it's a suturing belt among different ancient plates. Based on our investigation and indoor research of previous literatures during the past 20 years, this paper has briefly stated major geological features of the belt and its adjacent region, and put forward to some new points that the ocean, precursor of the belt, with remark of Karamaili ophiolite belt was a back-arc basin, that the region south of the belt was part of passive margin of the basin, and that the oceanic lithospheric plate was subducted northwards in the period of closure of the basin. Finally, the constraints of the belt on the distortion of ancient tectonic as well as metallogenic framework of the East Junggar region and the reconstruction of Paleozoic ocean-continent framework of the Central Asian region are briefly discussed.
Petrographic and geochemical characteristics of low-pressure granulite-facies gneisses from the western Awulale Mountains (in the western Tianshan Mountains) indicate that the protolith was a graywacke, which is featured by proximity of its origin and rapid deposition. In the chondrite-normalized diagram, the distribution patterns of rocks show steep LREE-type (light rare earth elements) and flat HREE-type, which suggests negative Eu anomaly and Nb, Ta, Ti, Ba, P and Sr depletions. The Cameca ion probe zircon U-Pb dating gave an upper interception age of 1609Ma±40Ma and a lower interception age of 764Ma±72Ma, representing the ages of magma crystallization and Pb-loss thermal event, respectively. The latter thermal event may represent the low-pressure metamorphic age. The outcrop of granulite-facies gneisses suggests that the Yili block may be underlain by Middle Proterozoic crystalline basement. The ~764 Ma thermal event probably records the break-up of the Rodinia supercontinent.
As an important strategic rare gas resource related to national security and the development of high-tech industries, helium is irreplaceable in liquid fuel rocket launch, deep diving and other fields, and has a profound impact on the high-quality development of "deep space, deep sea, deep earth, deep blue" and other fields. The integrated development of helium industry and innovation chains plays an important role to improve the security of resource supply. It has a great significance to promote the structural reform of helium supply and build a diversified helium supply system. This paper analyses the development situation of global helium resources industry and innovation chains integrated the resource side, the supply side, the consumption side, the trade side and the technology side. This study proposes the development status and challenges of China's helium industry and the corresponding development path of helium industry based on indicators such as resource conditions, capacity construction, foreign dependence, concentration of importing countries, concentration of importing enterprises, risk of importing countries, substitutability, the recycling rate, future supply and demand trend, industrial technology chain, management mechanisms. The results show that the global helium resource potential is considerable, but most countries remain in low exploration level; The global helium production capacity, supply, demand and trade pattern would be profoundly changing, but the contradiction between supply and demand would persist for a long time; The helium reservoir forming theory and exploration and development technology are underdeveloped, and the helium extraction equipment is continuously improved; The overall trend of global helium production develops well with a "helium heat" tide. The development subjects become diversified, which may change the global helium supply and demand pattern. China's helium development challenges and opportunities coexist considering the global helium resource industry chain pattern and the new trend of industry development. The 2022 is the key year to implement "the 14th Five Year Plan". It is desirable to conduct the work including the integrated chain analysis, the investigation and evaluation of helium resources, technical equipment research, the cultivation of market players, the construction of a diversified supply system. The above work will build an independent and controllable innovation chain, form a stable and resilient industrial chain, and provide helium resources guarantee for the development of high-tech industries.
Based on a preliminary investigation of the metallogenic geological background of superior mineral resources, features of metallogenic zones (belts), deposit types and resources potentials in Oceania, the authors analyzed the present situation of the “going aboard” strategy of the Chinese geological prospecting enterprises and the investment environment of Australia, Papua New Guinea and some other countries. Australia and Papua New Guinea possess huge reserves of Fe, Mn, Cu, Al and Ni as well as ores with strategic significance such as Au, U and rare earth, and these mineral resources are complementary to China’s domestic demand for mineral resources. Thus, these mineral resources in Australia and Papua New Guinea seem to be the ideal deposit mining projects for the Chinese mining companies wishing to look for developing chances aboard. At last, some suggestions for either long-term or short-term “going abroad” strategy are put forward based on previous work experience gained by the authors.
Specimen ZJZ-57, a nearly complete sauropod humerus excavated from the Upper Cretaceous Wangshi Group of Zhucheng area, Shandong Province, is described in this paper. Some derived features, such as a lateral bulge at the proximal onethird position of the lateral margin and a deltopectoral crest markedly expanded distally, indicate that ZJZ-57 represents a member of Titanosauria. However, it differs from all other titanosaurian sauropods in the following combined features:the proximal portion is strongly expanded, reaching 55% of the total length of the bone, and the humerus is a robust bone, with a robustness index (RI) of 0.39. Based on this specimen, the authors erect a new sauropod taxon:Zhuchengtitan zangjiazhuangensis gen. et sp. nov. This new taxon is possibly more closely related to Opisthocoelicaudia than to other known titanosaurian sauropods from Asia. This is the first ti-tanosaurian sauropod reported from the Upper Cretaceous strata of Shandong Province.
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