Abstract:This paper is the result of the natural resources survey engineering.
[Objective] Based on the spatial data of land use, Digital Elevation Model (DEM), vegetation and meteorological data we quantitatively analyzed temporal and spatial variation of natural resources and their effects on regional ecological environment in Northeast China from 1990 to 2018. [Methods] In accordance with the distribution regularity of nature, geography and natural resource in Northeast China, the study area was divided into 7 second- class zones and 14 third- class zones in comprehensive regionalization of natural resources by combining quantitative calculation and qualitative analysis. This paper analyzed temporal and spatial dynamic characteristics of natural resources and their ecological environmental effects in recent 30 years. [Results]The results showed as follows: (1) The main changes in the study area were the conversion of forest and grassland to cultivated land and water body and wetland from 1990 to 2018. Meanwhile, large areas of cultivated land was developed into built- up areas. In addition, the transformation of grassland to desertification was also prominent. The above phenomena were closely related to the local policy of revitalizing the old industrial base in Northeast China and strengthening agriculture and benefiting farmers policy, etc. (2)The overall ecological environment quality of the study area showed a declining trend, especially in I1, I5, I6 and I7 subregions(I1 Sanjiang plain temperate arable subregion, I5 Mountain temperate forest subregion of Lesser Khingan Mountains, I6 Piedmont plain temperate arable subregion and I7 Songliao plain temperate grass-tillage subregion. (3) The main reasons for the deterioration of ecological environment quality were that forest land and grassland were reclaimed as cultivated land and that grassland was turning to desertification. [Conclusions] In the past 30 years, large areas of forest and grassland in the study area have been transformed into cultivated land and water body and wetland, cultivated land has been developed into built- up areas and grassland desertification has intensified. There was a significant decreasing trend of ecological environment quality in the I1, I5, I6 and I7 subregions. The conversion of forest and grassland to cultivated land and grassland desertification mainly contributed to this phenomenon.

Abstract:This paper is the result of the geothermal geological survey engineering.
[Objective]The CO₂- plume geothermal system (CPGS) can achieve geological CO₂ storage during heat extraction. Under the background of carbon peaking and carbon neutralization, the economics of CPGS carbon storage attracts much attention. [Methods] Taking the Quantou Formation in the Songliao Basin as example, the influence of injection pressure, well spacing and reinjection temperature on the heat extraction rate were analyzed by numerical simulation in this paper. In addition, the benefit of CPGS and the cost of carbon storage were calculated and compared with conventional hydrothermal geothermal systems. [Results]Results show that the temperature of mining wells in CPGS exhibits a trend of "decrease-stabilization-decrease" due to the transformation of heat-carrying medium and thermal breakthrough. Typically, the well spacing has a significant impact on the temperature drop of the mining well. Smaller the well spacing contributes to larger temperature drop of the mining well. The heat extraction rate has a positive correlation with the reinjection pressure and a negative correlation with the reinjection temperature. The influence of well spacing on the heat extraction rate is limited. Compared with the conventional hydrothermal geothermal system, CPGS has three stages of heat recovery, namely, high, low and high stages successively. A low reinjection pressure and a close reinjection temperature with the reservoir temperature helps to shorten the time required for the CPGS to recover a similar heat energy with the water medium. [Conclusions]Taking the price of CO₂ and the benefits of heat extraction into account only, the well spacing has a dominating impact on the unit cost of CO₂ storage after the heating revenue offsets part of the cost of carbon storage. Small well spacing contributes to quick decrease of the unit cost of CO₂ storage. The unit cost of CO₂ storage can be reduced to 160 yuan/ton after 30 years of continuous mining when the well spacing is 300 m.

Abstract:This paper is the result of the mineral exploration engineering.
[Objective] There are increasing evidences show that the Tethys tectonic domain can be divided into three stages of the ProtoTethys, the Paleo- Tethys and the Neo- Tethys, among which the research on the formation and evolution of the Paleo- Tethys Ocean and related mineralization are relatively weak. [Methods] On the basis of the discovery of the Early Devonian Xiarihamu super-large nickel-cobalt sulfide deposit in the East Kunlun, the Late Carboniferous Malkansu large volcanic source sedimentary type manganese-rich deposit in the Pamir and the late Triassic Dahongliutan large pegmatite type lithium-beryllium deposit in the West Kunlun, this study focuses on the formation environment and tectonic evolution as the main line to find out their connection. It is proposed that the three large ore deposits represent the products of the tectonic transformation of Paleo- Tethys break, ocean expansion and ocean closure to continental collision, respectively. [Results] It is believed that after the closure of the Proto-Tethys ocean and continental collision, which was contemporaneous with the Paleo-Asian ocean at the end of the Silurian, the modified asthenosphere was partially melted and the northern margin of Gondwana continent breakup due to the mantle plume activity, forming the Xiarihamu super-large magmatic nickel-cobalt sulfide deposit related to the mantle-derived mafic-ultramafic rocks. With the further expansion of the Paleo- Tethys Ocean, the mature ocean was formed in the Early Carboniferous. In the Late Carboniferous, with transformation from rapid expansion to ocean subduction, the Malkansu large rhodochrosite-rich deposit was formed in the carbonate sedimentary of the ocean floor due to the ore forming material provided by the eruption of the mid-ocean ridge. After the closure of the Paleo-Tethys Ocean, it entered the collision orogenic stage in the Middle Triassic. In the Late Triassic post- collisional stage, high temperature hydrothermal fluid of S- type granite formed by the crust remelting, which lead to the formation of Dahongliutan large pegmatite-type lithium-beryllium deposit. The Early Paleozoic and Late Paleozoic alternation was the beginning of the Paleo- Tethys Ocean breakup. At this time the Qinling- Qilian- Kunlun Ocean as the representative of the Proto-Tethys Ocean has closed. Although the Paleo-Asian Ocean as a back-arc basin of the Proto-Tethys has not closed yet, the Xiarihamu nickel-cobalt deposit is the product of the re-cracking of continental crust after the Proto-Tethys orogeny， and it’ s not formed in the environment of the Proto - Tethys island arc or post- collision. Manganese is a lithophilic element, which is not enriched in magmatism. However, it enriched in exogenous deposition, which indicates that the new oceanic crust of the Early Carboniferous of Paleo-Tethys is rich in manganese, and the leached manganese ions formed sedimentary manganese carbonate in the alkaline environment of relatively quiet ocean floor in the Late Carboniferous, which represents the transition from a strong magmatism stage to a relatively quiet sedimentary environment. In the Dahongliutan, the distribution of S-type granitic batholith and its large-scale pegmatite-type lithium-beryllium ore deposit reflect the geodynamic background of crust remelting caused by strong collisional orogeny. Therefore, it’ s suggested the formation environment is post-orogeny or post-collision extension of the Paleo- Tethys. [Conclusions] As far as the existing facts of mineralization concerned, the Kangxiwa- Animaqing Paleo- Tethys suture zone in East Kunlun is of more geological significance than that of the Xijinwulan-Jinshajajiang in the southern Bayankara and the Longmuco-Shuanghu Paleo-Tethys suture zone in the Qiangtang.

Abstract:This paper is the result of groundwater geological survey engineering.
[Objective] There are hundreds of millions of people in more than 70 countries in the world facing the threat of high arsenic groundwater. Long-term drinking high-arsenic groundwater will lead to chronic arsenic poisoning, cancer, and seriously endanger health. The distribution of arsenic concentration in groundwater is the result of multiple factors including sedimentary environment, meteorological hydrology, mineral environment, and human activities. Therefore, it is necessary to start from the different physical and chemical properties of arsenic and select appropriate and targeted treatment technologies. [Methods] Based on the current pollution status of arsenic-bearing groundwater, the current situation and progress of arsenic-bearing groundwater treatment were analyzed by comprehensively considering various factors such as removal amount, treatment cost, remediation rate, and reversibility. [Results] This study comprehensively introduces the arsenic-bearing groundwater treatment technology, covering the research results of chemical oxidation, coagulation- sedimentation, adsorption, ion exchange, membrane technology and bioremediation, and shows the removal effect of different types of treatment methods on high- arsenic groundwater. In order to provide a meaningful reference for the comprehensive treatment of arsenic-bearing groundwater, the internal mechanism and the latest optimization measures for the technology are summarized, and the development trend of the arsenic- bearing groundwater treatment technology is prospected. [Conclusions] The current arsenic-bearing water treatment technology has many defects, and the generated waste or sludge may become a potential source of secondary pollution. Therefore, to better protect our environment from As, new mixing techniques and safe disposal methods for As- laden waste/sludge are required. The lack of awareness of drinking water safety and availability in remote areas also presents challenges for arsenic management, so an affordable, easy-tobuild technology that operates at the community or household level is needed to address the problem.

Abstract:This paper is the result of mineral exploration engineering.
[Objective] Helium is more and more widely used in scientific research, medicine and high-tech industries because of its unique physical properties. It is the responsibility of the geological industry to find more helium resources to meet the market demand.[Method] According to the principle of statistical analysis, the global helium exploration results and supply and demand situation are sorted and summarized.[Results] The distribution of helium resources in the world is extremely uneven. The main helium suppliers are the United States, Qatar, Russia and so on. Recently, many companies have begun to carry out helium exploration and development in North America, Russia, Qatar and Tanzania. Helium resources in some parts of North America are located in nitrogen rich reservoirs and have broad development prospects. Global helium exploration activities have set off a new upsurge.[Conclusion] In 2021, there was a supply gap in the global helium market, and the growth of global helium demand began to shift to Asia and the Middle East. It is suggested to pay great attention to the non-renewability and irreplaceability of helium, carry out helium resource potential evaluation project, explore the prospect of domestic non hydrocarbon helium deposits, strengthen international cooperation, carry out underground space evaluation and site selection of domestic helium reserves, and enhance China's helium storage capacity.

Abstract:This paper is the result of the geological survey engineering.
[Objective] There is great significance to find out the characteristics of urban shallow geological structure for urban underground space planning, development zone construction, geological disaster evaluation. While the nondestructive and strong anti-interference geophysical exploration technology can play a key role in providing urban underground geological information. [Method]In order to support the three-dimensional geological mapping of Chengdu City, 11 kinds of new and old geophysical exploration techniques are used to study the shallow geological structure of Chengdu City. [Results]The results show that: (1) GPR has a high resolution for the formation structure imaging and human structure identification near the surface; (2) Transient surface wave, mixed source surface wave and three-component resonance method have a strong recognition ability for the geological structure with a shallow depth of 50m, although the resolution is very high, but the detection depth is limited; (3) Microtremor survey method and high- density resistivity method have a better resolution for the geological structure with a shallow depth of 50 m, but under the deep of 50 m, the resolution is general, especially the high-density electrical method is greatly disturbed by humanity, and the detection effect is not stable; (4) Opossing coils transient electromagnetic method anti-interference ability is strong, the construction efficiency is high, the resolution is better in the range of 0-15 m, and general in the range of 50-200 m, which has a good identification ability for gypsum mudstone; (5) The semi-airborne TEM method can effectively identify the base form of Chang'an landfill and make up for the lack of conventional geophysical methods that the special site for detection; (6) The shallow seismic exploration has a good effect on the variation characteristics and fault structure characteristics of the sand shale interbedding within the depth range of 50- 300 m underground, and can effectively identify the lithology interface of the sand shale in combination with the natural gamma curve; (7) The audio-frequency magnetotelluric method can effectively identify the deep fracture in Chengdu Plain. [Conclusions]Based on the merits and demerits of various geophysical methods, a combined geophysical exploration scheme of shallow geological structure in Chengdu is established under conditions of multiple geological structures and complex working conditions, which is expected to provide a reference for the investigation of urban shallow geological structure in the future.

Abstract:The paper is the result of the natural resource comprehensive survey engineering.
[Objective]Global warming has challenged the international community in the modern world. Carbon neutralization and green and low-carbon transformation as an essential role in facing this challenge has been reaching a global consensus. Earth system science provides an important solution for the realization of the goal of carbon neutralization. How to find the main direction and working methods is an urgent problem to solve in geological survey related with the carbon neutralization strategy in Northwest China. [Methods]This paper summarizes the main geological methods in the process of carbon neutralization, and statistically analyses geological resources in Northwest China related with two main methods of carbon neutralization including emission decreasing and sink increasing, and provides suggestions for geological survey to serve green and low- carbon transformation. [Results]Northwest China is rich in clean energy such as natural gas and geothermal energy, as well as key minerals and other natural resources related to new energy. Among them, the geological natural gas resources are about 313991 × 108 m3, accounting for about 34.78% of the country. Geothermal energy is widely distributed and rich in types. Especially in Qinghai Province, the total amount of conservative and static dry hot rock resources in the depth range of 3- 6 km in Gonghe basin is 8974.74×1018 J. The key mineral resources related to clean energy such as lithium, cobalt, nickel and uranium in Northwest China rank among the top in China with lithium and cobalt reserves accounting for about 60% and 40% of the national reserves. Xinjiang is the largest uranium production base in China. Furthermore, there are abundant ecological types, surface matrix types, and a large number of high-quality spaces suitable for carbon capture， Utilization and storage site selection and geological energy storage to increase the carbon pool and sink in Northwest China. Northwest China is the important node to achieve the goal of carbon neutralization through the method of increasing carbon sink. [Conclusions]Northwest China can provide effective resource support for carbon emission reduction and carbon sink increase. Geological survey in Northwest China should be based on reality and give full play to its professional advantages in promoting survey of natural gas resources, exploring technology of geothermal resources development, strengthening research on the whole life cycle of key minerals, piloting comprehensive surface matrix ecological geology survey, conducting CCUS-related underground space survey, and build earth system science database for carbon neutral, we will continue to make efforts to provide important geological solutions and make due contributions to the realization of carbon neutral goals.

Abstract:This paper is the result of marine and environmental geological survey engineering.
[Objective]The environmental quality of surface sediments in Quanzhou Bay faces great ecological risks caused by heavy metals, but the researches focused on the influencing factors and potential sources were relatively weak. [Methods] By collecting surface sediment samples in offshore area of Quanzhou Bay, the distribution characteristics and enrichment degree of heavy metals were summarized based on element and grain size analysis, and the potential ecological risk was assessed using Hakanson method in study area. Positive definite matrix factor analysis (PMF) and principal component analysis (PCA) were further used to apportion the sources of heavy metals contamination. [Results]Grain size of surface sediments was low at the converging area of Jin river and Luoyang river, which were prone to enrich heavy metals. The order of surface sediments heavy metals enrichment factors was Hg > As > Cd > Pb > Zn > Cu > Cr > Ni. Overall ecological risk of surface sediments in Quanzhou Bay was moderate, and contribution of Cd to potential ecological risk was the highest (37.90%), followed by Hg (29.38%). Cr and Ni were mainly from rock weathering. Besides rock weathering, Cu, Zn and Pb were strongly affected by mining smelting. Cd and As were contributed by sewage disposal and fuel combustion, respectively. However, the sources of Hg were relatively complicated. Main sources of heavy metals in study area were mining smelting, rock weathering, sewage disposal and fuel combustion, and the contribution of them were 33.95%， 31.16%， 22.26% and 12.21%, respectively. [Conclusions]The transport of land substances with surface water runoff was the main cause for the ecological risk of surface sediments in Quanzhou Bay, and furthermore it is necessary to strength the research on the fate and environmental behavior of Hg in different media in the future.

Abstract:This paper is the result of soil and agricultural geological survey engineering.
[Objective] The east of Yinan County is the representative of Shandong Province with developed mining and agriculture in China. It is of great significance for environmental protection to control the local soil heavy metal pollution and its ecological health risks. [Methods] This study systematically investigated and analyzed 4779 surface soil samples, obtained the latest distribution data of Hg, Cd, Cr, Ni, As, Cu, Pb, Zn, and evaluated the ecological health risks and related problems by geoaccumulation index method, potential ecological hazard index method and health risk assessment model. [Results] (1) The mean content of each heavy metal mentioned above is roughly equivalent to the soil background value in Linyi City, but the Hg content is slightly high and its coefficient of variation is the largest, indicating that Hg in local soil is significantly affected by human activities. Compared with the risk screening values for soil contamination of agricultural land in China, Cu, Cr and Ni are the main elements exceeding the standard, the As, Cd, Cu and Pb contents are many times of the standard, and all of them may cause ecological health hazards. (2) According to the values of geoaccumulation index, the soil in this area is generally pollution-free, and the pollution of Hg and Cu was slightly stronger than that of the other six elements. (3) In terms of ecological risk, Hg and Cd are the main ecological risk elements, followed by As and Cu. The high ecological risk area includes three zones: the southeast of Tongjing Town, the area around Jinchang Village at the northwest of Jiehu Town, and the main urban area in the west of the county town. (4) In terms of human health risks, heavy metals have no non-carcinogenic risks and carcinogenic risks for adults, but they have non-carcinogenic risk and carcinogenic risk for children in few areas. Cr and As are the main non-carcinogenic risk elements, and As has the highest carcinogenic risk. [Conclusions] The soil quality is generally good in the eastern Yinan County. However, the southeast of Tongjing Town, the area around Jinchang Village at the northwest of Jiehu Town and the main urban area in the west of the county town are high ecological risk areas. Hg, Cr and As are the main elements with ecological health risks.

Abstract:This paper is the result of hydrogeological and environmental geological engineering.
[Objective] To understand the groundwater flow system in the middle and lower reaches of the Yangtze River plain and analyze its hydrochemical characteristics and evolution mechanism.[Methods] Based on the basic characteristics of hydrochemistry in Dangtu area of Maanshan City, the hydrochemistry evolution of shallow groundwater in this area was analyzed by using multivariate statistical analysis, hydrochemistry maps, ion ratio and reverse hydrogeochemical simulation. [Results] The results show that: (1) The groundwater in the study area is mainly alkaline water with low salinity. The cations in the groundwater are mainly Ca²⁺ and Mg²⁺, and the anions are mainly HCO₃^- and SO₄^2-. (2)According to Shukarev classification, the hydrochemical types of groundwater in the study area can be divided into seven categories, among which the hydrochemical types of loose rock pore water-bearing rock group and clastic rock pore fissure water-bearing rock group are mainly HCO₃^-Ca type, HCO₃^-Ca · Na type, HCO₃ · Cl-Ca · Na type and HCO₃^-Ca · Mg type. Chemical types of fractured water-bearing rock groups in bedrock are mainly HCO₃ · SO₄-Ca · Mg type and SO₄ · HCO₃^-Ca · Mg type. (3) The over-standard rate of shallow groundwater samples in the study area is 46%, and the overall water quality is poor. The components with higher over- standard rate are Mn, COD_Mn, nitrate (calculated as N), Fe, As, ammonia nitrogen (calculated as N), etc. (4) The chemical composition of groundwater in the study area is mainly controlled by rock weathering. Besides, there is the positive cation alternate adsorption of Na- Ca. (5) The results of reverse hydrogeochemical simulation quantitatively verify that water- rock interaction plays a leading role in the formation and evolution of shallow groundwater components in this area. [Conclusions] Groundwater in the study area is mainly low salinity and alkaline, which can be divided into loose rock pore water, clastic rock pore fissure water and bedrock fissure water. The main ion ratio and reverse hydrogeochemical simulation revealed that the chemical composition of shallow groundwater in this area was mainly formed after the groundwater leached calcite, dolomite and other carbonate minerals, quartz, feldspar and other silicate minerals, kaolinite and other clay minerals, rock salt and gypsum reached supersaturation.

Abstract:This paper is the result of groundwater geological survey engineering.
[Objective] In order to find out the characteristics of groundwater and its reason for evolution in Ningbo plain, and help to optimize the groundwater environment of Ningbo area. [Methods] Groundwater in Ningbo plain was analyzed comprehensively and systemically based on field survey and samples analysis, making full use of the previous data, then multiple methods including the mathematical statistics, the correlation matrices, Piper diagram, the ratio coefficient of main ions and environmental isotope were used for this study. [Results] The main of surface water and phreatic water were fresh water, however, confined water were mainly brackish water or salt water. HCO₃^- of phreatic water was the predominant anion and Cl^-, Ca²⁺, Na⁺ were all secondary. Contrastly, the dominant ions of surface water and confined water were Cl^- and Na⁺, HCO₃^- was the second. The four water were divided into twenty- three hydrochemical types, and surfer water and phreatic water were both influenced by precipitation evidently, whereas confined water deeply was closed in the aquifer during previous transgression, so there was little relationship with shallow water. [Conclusions] Compared with that in the 1970s, the distribution of fresh water body in confined aquifer Ⅰ of Ningbo urban area had no significant change, but that in confined aquifer Ⅱ was changing obviously by the influence of both human activities and natural water recycle. Salt water appeared in the scope of fresh water by hydrochemical evolution, and the scope of fresh water body expanded outside, overall, the distribution area increased by twelve square kilometer approximately, and the environmental effect was being towards positive tendency.

Abstract:This paper is the result of the geothermal geological survey engineering.
[Objective] Thermal properties are important parameters for the evaluation and utilization of shallow geothermal energy resources. [Methods] In this work, we collected 695 quaternary samples from alluvial and diluvial fans in Beijing plain. Then thermal properties and geotechnical parameters were tested, and the characteristics of thermal properties and their influence on shallow geothermal energy extraction were analyzed. [Results] The results show that the average range of quaternary samples in Beijing plain is 1.465-2.022 W/(m·K) for thermal conductivity, 0.450×10^-6-0.841×10^-6 m²/s for thermal diffusion, and 2.323-3.080 MJ/(m³ · K) for specific heat, respectively. There is a linear relationship between the thermal conductivity (λ) and the thermal diffusivity (κ) with correlation equations λ =1.6973κ + 0.6127. The finer the particles size of quaternary loose sediments, the lower the thermal conductivity. The thermal conductivity increases rapidly with the moisture content within the range of 0-5% and tends to stabilize within the range of 5%-20%. The thermal conductivity decreases with the increase of water content within the range of 20%-40%. Under natural state, the thermal conductivity increases with the increase of the density and decreases with the increase of the pore ratio. When the sample temperature is in the range of 0-40 ℃, the thermal conductivity first decreases and then increases and keeps lowest at 20 ℃. [Conclusions] Thermal properties of the quaternary vary with geological conditions. They are related to the storage, collection and diffusion capacity of shallow geothermal energy. The larger the thermal conductivity, thermal diffusivity and specific heat capacity, the greater the soil heat storage and thermal conductivity.

Abstract:This paper is the result of marine and environmental geological survey engineering.
[Objective] Carry out the differentiation of the sedimentary environments since the Late Pleistocene in the Luanhe River Delta, northern Bohai Bay, calculate and analyze the magnitude and controlling factors of the carbon sequestration rate (CSR), and further evaluate the regional carbon storage capacity. [Methods] In this paper, the reconstruction of the paleo- sedimentary environment since the Late Pleistocene was carried out on the core of hole BXZK03, and the parameters including particle size, age (AMS¹⁴C and OSL), water content, organic carbon, total carbon and other nutrients contents were sampled and analyzed. [Results] Since the Late Pleistocene, the strata were divided from bottom to top into five sedimentary environmental units, including flood plain, sand ridge, shallow sea, barrier sand bar (delta front), and lagoon. The CSRs were in the order of barrier sand bar 51.47 g/(m² · a)> beach sand ridge 32.59 g / (m² · a)> shallow sea 7.82 g/(m² · a)> lagoon 4.66g / (m² · a). Correlation analysis showed that there was a significant (P <0.01) linear correlation between total carbon, organic carbon and each nutrient element. Variance analysis suggested that CSRs were likely controlled by the deposition rate and carbon concentration, respectively. [Conclusions] Although the organic carbon concentrations of sediments in Luanhe River Delta were relatively low, there were relatively high organic CSRs due to an elevated deposition rate during Holocene. Therefore the Holocene sediment has a remarkable carbon storage capacity.

Abstract:This paper is the result of oil and gas exploration engineering.
[Objective]This paper takes Hangjinqi-Daying Uranium deposit as the research area, and we studied the carbonation type、 period and the characteristics of in-situ micro-zone carbon and oxygen isotopes, providing a new information and basis for the formation and cause of sandstone uranium deposits in this area. [Methods]By using the field observation, rock core collection of industrial hole in ore-bearing horizon, high power microscope observation, electron probe analysis, we distinguished the different stages of Carbonation(Mainly calcite). The C-O isotope test was carried out by using the SHRIMP stable isotope tracer technology, which provides a reasonable and more accurate way to tracing the formation process of sandstone uranium deposit.[Results]Both the mineralization period and post mineralization period of fluid have the source of genetic characteristics by using in-situ micro-area C-O isotopes testing method, and the oxygen isotope of calcite shows that the fluid has the characteristics of atmospheric water. it is believed that the natural gas moved to the north together with the groundwater forming the low- temperature hydrothermal fluid provided the carbon source. The "calcified wood"-like carbonated calcite in this area is mostly distributed along crystal caves or penetrated along cracks, and it is obviously the result of natural gas filling along the cracks in post mineralization period. Therefore, the natural gas- water mixed fluid effect can be extended to post mineralization period， which has the effect of superimposed enrichment and mineral preservation. [Conclusions]The application of electron probe, SHRIMP stable isotope tracing and other methods provide the core technical guarantee for in-situ micro-area stable isotope tracing, and provide an effective test method for the fine study of the characteristics of ore-forming fluids.

Abstract:This paper is the result of oil and gas exploration engineering.
[Objective] In this paper, the sedimentary and distribution characteristics of Carboniferous strata are studied in the study area from Wulungu Depression to Wulungu North Uplift in Junggar Basin, which provides a basis and reference for the study of geological structure and oil and gas exploration in this area. [Methods]Acquisition of magnetotelluric sounding data, combined with previous gravity, magnetic and electrical seismic data, using two- dimensional conjugate gradient inversion, optimization of electrical stratification technology to obtain the distribution characteristics of Carboniferous strata and fault structure, provides an effective method for the study of Carboniferous strata in igneous rock covered area. [Results] Using magnetotelluric sounding technology combined with gravity, magnetic, electrical and seismic data to carry out comprehensive processing and analysis, the thickness map and burial depth map of the Carboniferous system in the study area were obtained, the interface between the upper and lower Carboniferous strata was preliminarily determined, and the distribution characteristics of the Carboniferous strata were identified. The Suosuoquan sag, Fuhai depression and Zhaheba depression are three subsidence centers of Carboniferous strata, which have good prospects for oil and gas exploration. [Conclsions] In igneous rock covered area, the comprehensive processing and interpretation technology of magnetotelluric sounding and gravity-magnetic-electric-seismic provides effective technical support for the study of Carboniferous strata.

Abstract:This paper is the result of the mineral exploration engineering.
[Objective] The Baiyun gold deposit, located in the eastern margin of the North China Craton, is one of the typical gold deposits in the Qingchengzi ore concentration area of Fengcheng City, Liaoning Province. By clarifying the formation age, genesis and tectonic background of the mafic dikes in the mining area, it is beneficial to deepen the understanding of the regional tectonic evolution process and the genesis of the deposit. [Methods] Based on the field geological characteristics of the deposit, the lamprophyres closely related to mineralization, have been studied in terms of petrography, chronology and geochemistry in this paper. [Results] LA-ICP-MS zircon U-Pb data reveals that the lamprophyre formed at (126.81±0.65) Ma, indicating that it developed in the Early Cretaceous. Petrogeochemical characteristics show that the lamprophyres belong to alkali series and potassium hypostatic rocks, which are rich in magnesium (MgO=3.63%- 4.07% , Mg^# =54- 60), potassium (K₂O/Na₂O=1.26- 3.47) and alkali (K₂O + Na₂O= 4.41%- 5.23% ). The lamprophyres are enriched in large ion lithophile elements (Rb, Th, U) and light rare earth elements, but depleted in high field strength elements (Nb, Ta, Ti) and heavy rare earth elements, and exhibit typical arc magmatic features associated with subduction. Isotopic geochemical characteristics demonstrate that the lamprophyres have a high concentration of radioactive Pb isotopes. The initial ¹⁷⁶Hf/¹⁷⁷Hf value of zircon is 0.282117-0.282471, with negative ε_Hf(t) values (-20.80--7.81), suggesting that the magma source is the enriched lithospheric mantle influenced by subducted melt/fluid metasomatism. [Conclusions] Integrated with the regional tectonic setting, the bottom of the lithospheric mantle was eroded by the heat of the asthenosphere mantle during the Cretaceous period due to the extensional environment caused by the subduction and rollback of the Paleo-Pacific plate, which resulted in partial melting and the formation of the Early Cretaceous mafic magma. The lamprophyres with arc characteristics in the Baiyun mining area may have formed along the Tanlu fault zone and its secondary faults. Therefore, the Early Cretaceous mafic magmatism in this region represents a response to the lithosphere thinning in the eastern North China Craton.

Abstract:This paper is the result of geological survey engineering.
[Objective]In order to further understand the tectonic evolution of the West Junggar region. [Methods]In this paper, the zircon UPb geochronology and Hf isotopes of Sugensala granites were carried out. [Results]The dating results show two stages of age. The first phase focused on 440-440 Ma and the second phase is concentrated in the 410-420 Ma. According to the characteristics of the zircon CL images, we consider a capture zircon age of (444.2±2.2) Ma and a crystallization zircon age of (415.6±1.1) Ma. It is implied there was a wide range of magmatic activity at least on late- Silurian in Boshchekul—Chingiz magmatic arc. The ε^Hf(t) values of the zircon range of 8.6-13.2, with a weighted average of 10.8±1.4, indicating that its original rock is derived from mantle materials. The one-stage Hf model ages (T_DM1) are 521-742 Ma and two-stage Hf model ages (T_DM2) are 565-858 Ma. The granite was derived from the younger crustal materials from partial melting of the depleted mantle which raised to crust and stayed for a period of time. It shows that the source rocks of granites were generated from partial melting of new crustal material. The new components of continental crust may mainly come from depleted mantle-derived basaltic magma. [Conclusions]We speculate that Junggar basin is composed of young crust which evolved from depleted mantle in the period of late Neoproterozoic to Early Paleozoic. It is helpful to the further understanding the nature and tectonic evolution for Boshchekul-Chingiz magmatic arc.

Abstract:This paper is the result of geological survey engineering.
[Objective]The Yusupualeke Tagh granitic pluton is located in the Mangya ophiolitic mélange zone, South Altun orogenic belt. It mainly comprises the medium-coarse grained porphyritic biotite monzonitic granite and medium-fine grained phenocryst-bearing biotite monzonitic granite. However, their formation ages, petrogenesis, and material sources are still controversial, which restricts the understanding of the geodynamic background for the pluton and the Early Palaeozoic tectonic evolution of the South Altun orogenic belt. [Methods]To determine the formation ages, petrogenesis, and material sources of the granitic pluton, we studied petrology, zircon U-Pb chronology, whole-rock geochemistry, biotite mineral chemistry, and Hf isotopic composition of the pluton in this paper. [Results]Our results show that the medium- coarse grained porphyritic biotite monzonitic granite yielded weight mean ²⁰⁶Pb/²³⁸U ages of 451- 447 Ma. Combined with the formation ages (430- 423 Ma) of medium- fine grained phenocrystbearing biotite monzonitic granite in our previous study, we concluded that the Yusupualeke Tagh pluton was generated at Early Paleozoic. The study of biotite mineral chemistry indicated that the studied granitoids were formed in a low- temperature/highpressure environment. Based on the mineral composition, whole rock geochemistry, and diagenetic condition, we believed that the studied granitoids should be genetically ascribed to I-type granite. According to Hf isotopic compositions, the studied granitoids show similar Hf isotopic compositions, suggesting that they probably have similar material sources. They were mainly derived from the partial melting of the juvenile crust and mixed a small amount of ancient crust during the emplacement. [Conclusions]Based on the formation age, genetic type, origin, and tectonic setting, and combined with the regional tectonic evolution, we proposed that the Yusupualeke Tagh granitic pluton was formed in an active continental margin setting related to the northward subduction of the South Altun ocean.

Abstract:This paper is the result of geological survey engineering.
[Objection]: The purpose of this study is to reveal the material composition, tectonic nature, age, metamorphism,and deformation of the Lancang Group, which are controversial but of great significance.The results will provide fundamental data for further reconstruction of the spatiotemporal framework of the Tethys.[Methods] Systematically syntheticstudies were performed based on 1: 50000 detailed field investigation and Laser Ablash Inductively Coupled Plasma Mass Spectrometer (LA-ICP-MS) U-Pb dating of zircons.[Results] The Lancang Group is characterized by a tectonic mélange with matrix and blocks. It underwent three stages of metamorphism and deformation, overall as athrust nappe accretionary orogen. The formation age of the Lancang group is determined as the Early Paleozoic based on the zircon U-Pb ages from detrital zircons and meta acid rocks and previous research data. The protolith of the high-pressure metamorphic rocks in the Lancang Group has the characteristics of magmatic arc, OIB and E- MORB, indicating that the Lancang Group experienced deep subduction and accretionary orogeny. [Conclusions] Combined with the available research data in this region and the results obtained in this paper, the Lancang Group is not a basement but an Early Paleozoic accretionary complex formed by the subduction of the Changning-Menglian Proto-Paleo-Tethys Ocean.

Abstract:This paper is the result of the geological survey engineering
[Objetive]The Yidun island arc, as a key part of Sanjiang Tethys orogenic belt, has been hottly debated on granitic intrusions and the related mineralization in recent years. But few studies are concerned with the rhyolites such as the Tumugou Formation. [Methods] Based on detailed field mapping, this paper has conducted research on petrology, geochemistry and chronology of the Tumugou Formation’ s rhyolite. [Results] LA-ICP-MS zircon U-Pb dating on one sample yield an age of 216.5 Ma, and proved that the rhyolites were formed in the Late Triassic. The rhyolites have contents of SiO₂ from 73.24% to 74.72%, alkali (K₂O+Na₂O) of 5.26% to 6.27% as calc-alkaline rock series. All the samples are enriched in large ion lithophile elements such as Rb, Th, U, K and light rare earth elements, but depleted in the high strength filed elements such as Nb, Ta, Ti, P and heavy rare earth elements, indicative of the characteristics of island- arc volcanic rocks. [Conclusions] According to the comprehensive study, it is concluded that the rhyolites were formed by partial melting of the lower continental crust during the westward subduction of the Ganzi-Litang oceanic crust in the Indo-Chinese epoch.

Abstract:This paper is the result of the geological survey engineering.
[Objective] Aperiod of A-type granite is developed in Dandong, Liaoning Province, which has been widely concerned because of its special genetic evolution, specific tectonic setting and important geodynamic significance.[Methods] In this paper, the SHRIMP zircon U-Pb chronology and petrogeochemical characteristics of the Fenghuangshan pluton in Dandong, Liaoning Province, were analyzed to explore the formation age, petrogenesis and geodynamic background of the pluton.[Results] The zircon U-Pb ages of the biotite syenogranite in Fenghuangshan, Liaodong are (122.3±1.7) Ma, (125.0±1.7) Ma and (122±2) Ma, representing that the magma of the biotite syenogranite in Fenghuangshan crystallized and intruded in the Early Cretaceous. Geochemical analysis shows that the SiO₂ content is 65.65%-73.62%, whereas that of K₂O and Na₂O is 3.52%-5.76% and 3.64%-4.26%, respectively. They also contain 13.4%~15.49% of Al₂O₃, with A/CNK ratio of 1.02-1.46, indicative of their peraluminous nature. The alkalinity rate (AR) ranges from 2.71 to 5.13, and this range is within the AR of aluminous A-type granites. Its FeO_t/MgO ranges from 4.69 to 18.05, which shows the A1 and A2 transition types of A-type granites. The Rb/Nb ranges from 6.02 to 8.64, which display a higher level than that of the continental crust of 2.2-4.7. This implies that continental crust components, which lead to an increase in Rb content, had a significant influence on its formation. The biotite syenogranites are relatively enriched in large ion lithophileelements Rb, Th, Zr, Hf, and depleted in Sr, P, Ba, Ti, Nb. The total content of rare earth elements is high, the fractionation between light and heavy rare earth elements is not obvious, and Eu has obvious negative anomalies. [Conclusions] In summary, Fenghuangshan pluton might have been produced in stretching environment related to intracontinental shearing, which ought to be a response to the tectonization of the East Asia continental margins caused by the subduction of plates starting from the Middle Jurassic.

Abstract:

Abstract:

Abstract:

Abstract:

Abstract: