Formation,evolution,reconstruction of black shales and their influence on shale oil and gas resource

Black shales are important products of material cycling and energy exchange among the lithosphere,atmosphere,hydrosphere,and biosphere.They are widely distributed throughout geological history and provide essential energy and mineral resources for the development of human society.They also record the evolution process of the earth and improve the understanding of the earth.This review focuses on the diagenesis and formation mechanisms of black shales sedimentation,composition,evolution,and reconstruction,which have had a significant impact on the formation and enrichment of shale oil and gas.In terms of sedimentary environment,black shales can be classified into three types:Marine,terrestrial,and marine-terrestrial transitional facies.The formation processes include mechanisms such as eolian input,hypopycnal flow,gravity-driven and offshore bottom currents.From a geological perspective,the formation of black shales is often closely related to global or regional major geological events.The enrichment of organic matter is generally the result of the interaction and coupling of several factors such as primary productivity,water redox condition,and sedimentation rate.In terms of evolution,black shales have undergone diagenetic evolution of inorganic minerals,thermal evolution of organic matter and hydrocarbon generation,interactions between organic matter and inorganic minerals,and pore evolution.In terms of reconstruction,the effects of fold deformation,uplift and erosion,and fracturing have changed the stress state of black shale reservoirs,thereby having a significant impact on the pore structure.Fluid activity promotes the formation of veins,and have changed the material composition,stress structure,and reservoir properties of black shales.Regarding resource effects,the deposition of black shales is fundamental for shale oil and gas resources,the evolution of black shales promotes the shale oil and gas formation and storage,and the reconstruction of black shales would have caused the heterogeneous distribution of oil and gas in shales.Exploring the formation mechanisms and interactions of black shales at different scales is a key to in-depth research on shale formation and evolution,as well as the key to revealing the mechanism controlling shale oil and gas accumulation.The present records can reveal how these processes worked in geological history,and improve our understanding of the coupling mechanisms among regional geological events,black shales evolution,and shale oil and gas formation and enrichment.

Zircon U-Pb ages and provenance characteristics of the Zhiluo Formation sandstones and the formation background of the uranium deposit in Huangling area,Ordos Basin,China

The newly discovered medium-scale Huangling uranium deposit is located in the Shuanlong area of the southeast Ordos Basin.This paper presents the systematic geochemical and zircon U-Pb studies on the Zhiluo Formation sandstones in the Huanling area.The data obtained play an important role in deducing the provenance and tectonic setting of the source rocks.The results show that the lower part of the Zhiluo Formation is mainly composed of felsic sedimentary rocks.The source rocks originated from a continental island arc environment in terms of tectonic setting.U-Pb ages of detrital zircons obtained can be roughly divided into three groups:170‒500 Ma,1600‒2050 Ma,and 2100‒2650 Ma.Based on the characteristics of trace elements and rare earth elements(REE)and the zircon U-Pb dating results,it is considered that the Cryptozoic Edo provenance of the Zhiluo Formation mainly includes magmatic rocks(such as granodioritic intrusions)and metamorphic rocks(such as gneiss and granulite)in the orogenic belts on the northern margin of the North China Plate and in the Alxa Block.Based on sedimentological and petrological results,it can be concluded that the provenance of clastic sediments in the Zhiluo Formation was in north-south direction.The preconcentration of uranium is relatively low in the Lower Zhiluo Formation in the Huangling area.Meanwhile,the paleocurrent system in the sedimentary period is inconsistent with the ore-bearing flow field in the mineralization period,which restricts the formation of large-scale and super-large-scale uranium deposits and ore zones in the southeast Ordos Basin.The understanding of provenance directions will provide crucial references for the Jurassic prototype recovery and paleo-geomorphology of the Ordos Basin and the prediction of potential uranium reservoirs of the basin.

A PARAGON OF SUCCESSFUL SINO-JAPANESE COOPERATION——CHINESE RESEARCH CENTER FOR MINERAL RESOURCES EXPLORATION

With the approval of the Chinese and Japanese governments, the Chinese Research Center for Mineral Resources Exploration was inaugurated on August 11, 1994, a project of technological cooperation co-sponsored by the CAS and Japan International Cooperation Agency (JICA). Its domestic partners include the Geological Bureau of

Classification and mineralization of global lithium deposits and lithium extraction technologies for exogenetic lithium deposits

A reasonable classification of deposits holds great significance for identifying prospecting targets and deploying exploration. The world ’s keen demand for lithium resources has expedited the discovery of numerous novel lithium resources. Given the presence of varied classification criteria for lithium resources presently, this study further ascertained and classified the lithium resources according to their occurrence modes, obtaining 10 types and 5 subtypes of lithium deposits(resources) based on endogenetic and exogenetic factors. As indicated by surveys of Cenozoic exogenetic lithium deposits in China and abroad,the formation and distribution of the deposits are primarily determined by plate collision zones, their primary material sources are linked to the anatectic magmas in the deep oceanic crust, and they were formed primarily during the Miocene and Late Paleogene. The researchers ascertained that these deposits,especially those of the salt lake, geothermal, and volcanic deposit types, are formed by unique slightly acidic magmas, tend to migrate and accumulate toward low-lying areas, and display supernormal enrichment. However, the material sources of lithium deposits(resources) of the Neopaleozoic clay subtype and the deep brine type are yet to be further identified. Given the various types and complex origins of lithium deposits(resources), which were formed due to the interactions of multiple spheres, it is recommended that the mineralization of exogenetic lithium deposits(resources) be investigated by integrating tectono-geochemistry, paleoatmospheric circulation, and salinology. So far, industrialized lithium extraction is primarily achieved in lithium deposits of the salt lake, clay, and hard rock types. The lithium extraction employs different processes, with lithium extraction from salt lake-type lithium deposits proving the most energy-saving and cost-effective.

Analysis of the world oil and gas exploration situation in 2021

The global exploration investment, new oil and gas discoveries, exploration business adjustment strategies of oil companies in 2021, and future favorable exploration domains are systematically analyzed using commercial databases such as IHS and public information of oil companies. It has been found that the world oil and gas exploration situation in 2021 has continued the downturn since the outbreak of COVID-19. The investment and drilling workload decreased slightly, but the success rate of exploration wells, especially deepwater exploration wells, increased significantly, and the newly discovered reserves increased slightly compared with last year. Deep waters of the passive continental margin basins are still the leading sites for discovering conventional large and medium-sized oil and gas fields. The conventional oil and gas exploration in deep formations of onshore petroliferous basins has been keeping a good state, with tight/shale oil and gas discoveries made in Saudi Arabia, Russia, and other countries. While strengthening the exploration and development of local resources, national, international, and independent oil companies have been focusing on major overseas frontiers using their advantages, including risk exploration in deep waters and natural gas. Future favorable exploration directions in the three major frontiers, the global deep waters, deep onshore formations, and unconventional resources, have been clarified. Four suggestions are put forward for the global exploration business of Chinese oil companies: first, a farm in global deepwater frontier basins in advance through bidding at a low cost and adopt the “dual exploration model” after making large-scale discoveries;second, enter new blocks of emerging hot basins in the world through farm-in and other ways, to find large oil and gas fields quickly;third, cooperate with national oil companies of the resource host countries in the form of joint research and actively participate exploration of deep onshore formations of petroliferous basins;fourth, track tight/shale oil and gas cooperation opportunities in a few countries such as Saudi Arabia and Russia, and take advantage of mature domestic theories and technologies to farm in at an appropriate time.

Application of Transient Electromagnetic Method with Multi-Radiation Field Sources in Deep Edge Mineral Resources Exploration

In recent years,in order to meet the practical needs of deep edge mine detection with large depth and high precision,transient electromagnetic method(TEM)near emission source detection mode has become an international advanced method(Xue et al.,2020).

Geochemical characteristics and genetic type of a lithium ore (mineralized) body in the central Yunnan Province, China

Lithium ore (mineralized) bodies in the area A of central Yunnan Province belong to a sedimentary-type, which are controlled by stratum. The studied ore (mineralized) body mainly occurs in the Middle Permian Liangshan Formation. This work described the morphology, structures, main ore types and geochemical characteristics of this ore body in detail, and discussed the ore-forming material source, occurrence state of lithium and the formation mechanism of lithium ores to clarify the prospecting marks. In the further exploration, comprehensive evaluation of the lithium resources of known bauxite ore bodies in central Yunnan Province should be strengthened, and the exploration of hidden lithium ore bodies should be intensified in order to discover more large and super-large lithium orebodies, which will fill the gap of the national demand for lithium resources, and promote the national defense construction and new energy industry development.

Growth behavior and resource potential evaluation of gas hydrate in core fractures in Qilian Mountain permafrost area, Qinghai-Tibet Plateau

The Qilian Mountain permafrost area located in the northern of Qinghai-Tibet Plateau is a favorable place for natural gas hydrate formation and enrichment,due to its well-developed fractures and abundant gas sources.Understanding the formation and distribution of multi-component gas hydrates in fractures is crucial in accurately evaluating the hydrate reservoir resources in this area.The hydrate formation experiments were carried out using the core samples drilled from hydrate-bearing sediments in Qilian Mountain permafrost area and the multi-component gas with similar composition to natural gas hydrates in Qilian Mountain permafrost area.The formation and distribution characteristics of multi-component gas hydrates in core samples were observed in situ by X-ray Computed Tomography(X-CT)under high pressure and low temperature conditions.Results show that hydrates are mainly formed and distributed in the fractures with good connectivity.The ratios of volume of hydrates formed in fractures to the volume of fractures are about 96.8%and 60.67%in two different core samples.This indicates that the fracture surface may act as a favorable reaction site for hydrate formation in core samples.Based on the field geological data and the experimental results,it is preliminarily estimated that the inventory of methane stored in the fractured gas hydrate in Qilian Mountain permafrost area is about 8.67×1013 m3,with a resource abundance of 8.67×108 m3/km2.This study demonstrates the great resource potential of fractured gas hydrate and also provides a new way to further understand the prospect of natural gas hydrate and other oil and gas resources in Qilian Mountain permafrost area.

Quantitative Prediction for Deep Mineral Exploration

On reviewing the characteristics of deep mineral exploration, this article elaborates on the necessity of employing quantitative prediction to reduce uncertainty. This is caused by complexity of mineral deposit formational environments and mineralization systems as increase of exploration depth and incompleteness of geo-information from limited direct observation. The authors wish to share the idea of ＂seeking difference＂ principle in addition to the ＂similar analogy＂ principle in deep mineral exploration, especially the focus is on the new ores in depth either in an area with discovered shallow mineral deposits or in new areas where there are no sufficient mineral deposit models to be compared. An on-going research project, involving Sn and Cu mineral deposit quantitative prediction in the Gejiu （个旧） area of Yunnan （云南） Province, China, was briefly introduced to demonstrate how the ＂three-component＂ （geoanomaly-mineralization diversity-mineral deposit spectrum） theory and non-linear methods series in conjunction with advanced GIS technology, can be applied in multi-scale and multi-task deep mineral prospecting and quantitative mineral resource assessment.

Delineation of Potential Mineral Resources RegionBased on Geo-anomaly Unit

The geological anomaly unit method (GAUM) is a new way to delineate and evaluate ore finding targets in line with the “geological anomaly ore finding theory”. Comprehensive ore finding information from geological, geochemical and geophysical data is used for quantitative measurement of the “ore forming geological anomaly unit” in this paper. The main procedures are shown as follows: (1) The geo anomalous events associated with gold mineralization are analyzed in Tongshi gold field; (2) The zonation in the concentrated heavy minerals and the stream sediment elements of ore forming geo anomaly are studied in detail; (3) The deep geological structural framework is deduced by means of the synthetic geological interpretation of gravity and magnetic information; (4) The ore controlling geo anomalies and ore anomalies are chosen as the variables of the favorable ore forming indexes that can be used for the quantitative delineation and evaluation of the potential ore forming regions.

Concealed porphyry delineation based on nonlinear three-dimensional densitydifference inversion: An example in the Beiya mine area, Western Yunnan, China

Intermediate acid-complex rock masses with low-density characteristics are the most important prospecting sign in the Beiya area, of western Yunnan province, and provide a physical basis for good gravity exploration. It is usually difficult to obtaining solutions in connection with actual geological situations due to the ambiguity of the conventional gravity-processing results and lack of deep constraints. Thus, the three-dimensional (3D) inversion technology is considered as the main channel for reducing the number of solutions and improving the vertical resolution at the current stage. The current study starts from a model test and performs nonlinear 3D density-difference inversion called “model likelihood exploration”, which performs 3D inversion imaging and inversion of the known model while considering the topographic effects. The inversion results are highly consistent with those of the known models. Simultaneously, we consider the Beiya gold mine in Yunnan as an example. The nonlinear 3D densitydifference inversion technology, which is restricted by geological information, is explored to obtain the 3D density body structure below 5 km in the mine area, and the 3D structure of the deep and concealed rock masses are obtained using the density constraints of the intermediate-acid-complex rock masses. The results are well consistent with the surface geological masses and drilling-controlled deep geological masses. The model test and examples both show that the 3D density-difference nonlinear inversion technology can reduce inversion ambiguity, improve resolution, optimize the inversion results, and realize “transparency” in deeply concealed rock masses in ore-concentrated areas,which is useful in guiding the deep ore prospecting.

Prospect for strategic minerals exploration and development,investment environment and cooperation in Mozambique

Mozambique is an essential country in the Belt and Road Initiative,and it is also to cooperation between China and with Africa in energy resources.It is located in the critical node of the“East Africa Channel”and close to the“African Twin Ocean Railway”,which is an important strategic position.Mozambique has abundant mineral resources and vast reserves of advantageous minerals.The natural gas reserves of Mozambique ranked second in Africa.It also has world--class scale graphite and rich iron,gold,copper,niobium-tantalum and other resources.In recent years,the mining industry in this country has been rising and attracting many foreign companies to invest,including international mining giants such as Vale,Rio Tinto and large mining enterprises of China.This paper systematically studies the mineral resources endowment,exploration and development situations of natural gas,graphite,titanium-zircon placer deposits,niobium-tantalum,gold,iron and other strategic minerals in Mozambique,comprehensively analyzes the mining investment environment and the current situation of exploration and development of Chinese enterprises in Mozambique,and replans four safeguard areas of strategic mineral resources in critical short supply.Mozambique generally has good prospects of mining investment and a stable foundation for cooperation with China.Chinese enterprises can focus on oil and natural gas,graphite,titanium,zirconium,niobium,tantalum,and iron,which complement the needs of China,expand the mining capacity cooperation,and improve the ability to secure strategic mineral resources supply.

Function of Permian Special Gastropod Faunas in the Upper Yangzi Area to Determining Sedimentary Facies and Their Significance for Searching for Mineral Resources

The 'Upper Yangzi Area' includes a greater part of Guizhou Province and extensive regions of the eastern part of Sichuan Province and Yunnan Province. This area was a stable plateform with varied sedimentary environments during the Permian.A lot of carbonate strata, clastic strata, coal-bearing strata, siliceous strata, etc. deposited in this area during Permian. In this period, adapting themselves to varied environments,

The copper polymetallic deposits and resource potential in the Tibet Plateau

Many large and super-large copper deposits have been discovered and explored in the Tibet Plateau,which makes it the most important copper resource reserve and development base in China.Based on the work of the research team,the paper summarizes the geological characteristics of the main copper deposits in Tibet and puts forward a further prospecting direction.A series of large accumulated metal deposits or ore districts from subduction of Tethys oceanic crust to India-Asia collisionhave been discovered,such as Duolong Cu(Au)ore district and Jiama copper polymetallic deposit.The ore deposits in the Duolong ore district are located in the lowstand domain,the top of lowstand domain,and the highstand domain of the same magmatic-hydrothermal metallogenic system,and their relative positions are the indicators for related deposits in the Bangong Co-Nujiang metallogenic belt.The polycentric metallogenic model of the Jiama copper polymetallic deposit is an important inspiration for the exploration of the porphyry mineralization related to collision orogeny.Further mineral exploration in the Tibet Plateau should be focused on the continental volcanic rocks related to porphyry-epithermal deposits,orogenic gold deposits,hydrothermal Pb-Zn deposits related to nappe structures,skarn Cu(Au)and polymetallic deposits,and the Miocene W-Sn polymetallic deposits.

The Uranium Prospects in Mika Region, Northeastern Nigeria

Uranium exploration especially in currently non-producing countries like Nigeria possesses high economic prospect. This study investigates a new uranium prospect in Mika, Northeastern Nigeria. The Mika uranium mineralization is located in Mika, Taraba State. Two lodes were identified and additional nine (9) trenches were added. The main lode in the west extends about 10 m, ore vein strikes 348°, inclination 42°and the strike of the lode 306°with average uranium content of 18%. The eastern trench is about 8 × 4 × 6 m which exposes a veinlet of pitchblende. From the petrography, one can deduce that the granitic host rock has suffered deformation resulting in crushing of quartz crystals and stretching of plagioclase. The uraninite and chalcedony in the late phase filled up the fractures along the crystal grain boundaries as veinlets. The laboratory gamma ray analysis of the samples showed that the secondary uranium content is 0.1%, while the primary uranium ore grade is 1.5%. Radiometric in situ measurements showed that Th and K ranges from 47.3 - 3654 ppm and 4.26% - 6.26% respectively. From the survey, a strong radiometric zone extends 800 × 35 m in an NW-SE direction and has highest radiation content of 1200 cpm against the background count rate of 30 cpm. Generally, the uranium concentrations in the ores in Mika area range from 0.03% - 0.12%. Since only the surface occurrences have been explored, the study area is a good prospect for future development when properly explored. The North-eastern Nigeria has been roughly explored by Nigeria Uranium Mining Company (NUMCO) in 1980, but no formal exploration had been followed after that, especially near the site of this article. The company (ACE Mines, Ltd) of the first author was among the few uranium mining companies approved in the list of Nigerian Geological Survey agency of Abuja in Nigeria. The authors determined the coordinates of the site in their first survey which formed the prospect area in the licence.

矿产勘查市场周期性波动与我国矿产勘查趋势分析

在社会经济发展的驱动下,矿产勘查市场具有明显的周期性波动,包括长周期变化、中短周期变化和随机性变化。澳大利亚50年矿产勘查市场变化表明,经济发展的长周期变化决定了矿产资源供需关系基本面,矿产资源供需关系基本面决定了矿产勘查投入的长周期变化;经济发展中短周期变化决定了矿产品价格周期性变化,矿产品价格周期性变化决定了矿产勘查投入的中短周期变化。在国家新一轮找矿突破战略行动驱动下,我国矿产勘查活动进入新一轮增长周期,并呈现出与全球不同的变化特征。2020年以来,我国矿产勘查投入连续4年实现增长,且增速逐年扩大,2023年同比增长25.4%,矿产勘查市场内生回升动力不断增强。2016年之后,主要受国内政策环境的影响,我国矿产勘查投入变化偏离了全球勘查市场走势。综合判断,我国矿产勘查市场正处在长中短周期叠加、政策环境发生明显改善的特殊阶段。经济发展长周期变化和中短周期变化对矿产勘查投入形成较大的下行压力,而政策环境改善对市场形成了较强的上行拉力,未来2~3 a将是政策红利集中释放的时间,本轮矿产勘查增长周期可能将延续2~3 a时间。

地质科学新思维观与新时代地质工作战略思考

【研究目的】通过分析新时代地质工作面临的挑战和机遇,构建地质科学新思维观,力求使地质工作健康、持续、稳定发展。【研究方法】从理论与实践、历史与未来、守正与创新、发展与保护的逻辑出发,研究提出地质科学新思维观,并分析其意义。【研究结果】地质科学新思维观主要是:(1)地质大基础观,加强区域基础地质调查,加强全国资源、环境、生态、灾害、空间国情调查,深化对地球认知的水平。(2)地质大资源观,将全部地质要素进行整体调查、开发与保护,实现各类地质要素资源综合效益的最大化。能源和战略性矿产是最核心的地质资源,地质工作要把保障国家能源和战略性矿产资源安全摆在首位。(3)地质大生态观,发挥地质工作在促进生态系统稳定与可持续中的作用,解决生态系统问题或维护生态系统功能。(4)地质大数据观,充分运用现代信息技术,全面实现地质工作的数字化、智能化转型。(5)地质大系统观,将地球与自然、社会、经济系统作为整体综合考虑,维持地球系统稳定和人类经济社会可持续发展,推进传统地质科学向地球系统科学转变。【结论】基于新思维观,新时代地质工作要:树立地质大基础观,提高基础地质调查水平,深化对地球发展演化的认知;树立地质大资源观,巩固传统地质找矿工作,实现新一轮找矿取得重大突破,拓展自然资源调查评价新领域;树立地质大生态观,开辟生态地质,为生态修复与保护提供地质解决方案;树立地质大数据观,构建地质科学研究新范式,为社会需求提供智慧化地质解决方案;树立地质大系统观,发展和完善地球系统科学,建立新一代地质科学知识体系。

从“直接找矿”到“智能找矿”:脉络与启示

本文通过回顾固体矿产找矿的技术逻辑演进历程,指出中国固体矿产找矿经历“直接找矿”“经验找矿”“理论找矿”“信息找矿”“智能找矿”5个层级,“智能找矿”是未来一段时间的发展方向。相比发达国家固体矿产找矿的发展演变情况,中国发展历程虽然后发但基本相似,可以借鉴其夯实基础地质数据、构建精细矿床模型、运用现代勘查技术、积极探索智能找矿等方面的经验做法。着眼于当前新一轮找矿突破战略行动的紧迫需求,就找矿工作提出4方面建议:一是加速推进找矿工作智能化进程,从野外调查、数据处理、系统构建和预测示范进行全方位改造;二是以遥感调查和航空物探为先导,加快西部地区“直接找矿”;三是充分利用新技术新方法,加强中东部地区“信息找矿”;四是精准实施科技攻关,强化大型资源基地找矿科技支撑。

高光谱遥感技术在矿山地质环境调查中的应用

矿山地质环境受矿产资源开采活动的影响而产生剧烈变化,直接或间接影响了生态环境的可持续发展。近年来,高光谱遥感技术因其具备高光谱分辨率、空间信息与光谱信息合一的优势,解决了传统遥感技术仅能识别大致地物的问题,被广泛应用于矿山地质环境研究与监测。在梳理相关文献的基础上,介绍了高光谱遥感技术原理及发展现状,归纳了高光谱遥感技术在矿区植被、矿区水体、矿区土壤和矿区大气等方面的应用与监测;对矿区高光谱发展前景进行展望,认为未来随着遥感技术的发展对矿山地质环境的监测将逐渐有序化、长期化。

镍资源找矿突破与综合开发利用

镍资源是国民经济发展的重要战略资源,也是重要的关键矿产;我国是全球最大的镍金属消费国,也是镍金属原料稀缺国,镍矿产原料对外依存度居高不下,亟需实现镍资源找矿突破、推动镍资源综合开发利用、拓宽镍资源进口渠道,保障镍资源安全稳定供给。本文在综合分析镍产业最新数据的基础上,梳理了全球和我国镍资源禀赋、供需现状,总结了国内外镍矿床成因类型、时空分布规律和找矿前景,分析了我国镍资源产业发展和供应保障面临的问题,提出了镍矿勘查开发的关键技术及综合利用途径。为保障稳定供应和安全发展,从国际和国内两方面提出了我国镍资源保障路径及对策。在国际方面,稳定以印度尼西亚、菲律宾为代表的重要镍资源进口市场,加大投资镍资源海外矿业项目,增强中资企业的国际竞争能力;加强国际合作,实现镍资源进口渠道的多元化。在国内方面,加大镍资源勘查力度;加强镍资源综合利用,提高再生镍资源利用率;优化传统技术工艺,调整产业结构;强化镍资源储备基地建设,保障有效增储;重视海底铁锰结核等潜在镍矿资源的开采技术研究。