Comparative Analysis for Evaluating Wind Energy Resources Using Intelligent Optimization Algorithms and Numerical Methods

Statistical distributions are used to model wind speed,and the twoparameters Weibull distribution has proven its effectiveness at characterizing wind speed.Accurate estimation of Weibull parameters,the scale(c)and shape(k),is crucial in describing the actual wind speed data and evaluating the wind energy potential.Therefore,this study compares the most common conventional numerical(CN)estimation methods and the recent intelligent optimization algorithms(IOA)to show how precise estimation of c and k affects the wind energy resource assessments.In addition,this study conducts technical and economic feasibility studies for five sites in the northern part of Saudi Arabia,namely Aljouf,Rafha,Tabuk,Turaif,and Yanbo.Results exhibit that IOAs have better performance in attaining optimal Weibull parameters and provided an adequate description of the observed wind speed data.Also,with six wind turbine technologies rating between 1 and 3MW,the technical and economic assessment results reveal that the CN methods tend to overestimate the energy output and underestimate the cost of energy($/kWh)compared to the assessments by IOAs.The energy cost analyses show that Turaif is the windiest site,with an electricity cost of$0.016906/kWh.The highest wind energy output is obtained with the wind turbine having a rated power of 2.5 MW at all considered sites with electricity costs not exceeding$0.02739/kWh.Finally,the outcomes of this study exhibit the potential of wind energy in Saudi Arabia,and its environmental goals can be acquired by harvesting wind energy.

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).

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.

Research Progress on the Electrical Properties of Gas Hydrate-bearing Sediments

Electrical properties are important physical parameters of natural gas hydrate,and,specifically,resistivity has been widely used in the quantitative estimation of hydrate saturation.There are three main methods to study the electrical properties of gas hydrate-bearing sediments:experimental laboratory measurements,numerical simulation,and resistivity logging.Experimental measurements can be divided into three categories:normal electrical measurement,complex resistivity measurement,and electrical resistivity tomography.Experimental measurements show that the resistivity of hydrate-bearing sediment is affected by many factors,and its distribution as well as the hydrate saturation is not uniform;there is a distinct non-Archie phenomenon.The numerical method can simulate the resistivity of sediments by changing the hydrate occurrence state,saturation,distribution,etc.However,it needs to be combined with X-ray CT,nuclear magnetic resonance,and other imaging techniques to characterize the porous characteristics of the hydrate-bearing sediments.Resistivity well logging can easily identify hydrate layers based on their significantly higher resistivity than the background,but the field data of the hydrate layer also has a serious non-Archie phenomenon.Therefore,more experimental measurements and numerical simulation studies are needed to correct the parameters of Archie’s formula.

Quantitative Method of Classification and Discrimination of a Porous Carbonate Reservoir Integrating K-means Clustering and Bayesian Theory

Reservoir classification is a key link in reservoir evaluation.However,traditional manual means are inefficient,subjective,and classification standards are not uniform.Therefore,taking the Mishrif Formation of the Western Iraq as an example,a new reservoir classification and discrimination method is established by using the K-means clustering method and the Bayesian discrimination method.These methods are applied to non-cored wells to calculate the discrimination accuracy of the reservoir type,and thus the main reasons for low accuracy of reservoir discrimination are clarified.The results show that the discrimination accuracy of reservoir type based on K-means clustering and Bayesian stepwise discrimination is strongly related to the accuracy of the core data.The discrimination accuracy rate of TypeⅠ,TypeⅡ,and TypeⅤreservoirs is found to be significantly higher than that of TypeⅢand TypeⅣreservoirs using the method of combining K-means clustering and Bayesian theory based on logging data.Although the recognition accuracy of the new methodology for the TypeⅣreservoir is low,with average accuracy the new method has reached more than 82%in the entire study area,which lays a good foundation for rapid and accurate discrimination of reservoir types and the fine evaluation of a reservoir.

Assessment of acoustic backscatter intensity surveying on deep-sea ferromanganese crust: Constraints from Weijia Guyot, western Pacific Ocean

Near-bottom observation data from the manned deep submersible Jiaolong with high-precision underwater positioning data from Weijia Guyot,Magellan Seamounts in the Western Pacific Ocean are reported.Three substrate types were identified:Sediment,ferromanganese crust,and ferromanganese crust with a thin cover of sediment.The ferromanganese crusts show clear zoning and their continuity is usually disturbed by sediments on areas of the mountainside with relatively gentle slope gradients.The identified substrate spatial distributions correspond to acoustic backscatter intensity data,with regions of high intensity always including crust development and regions of low intensity always having sediment.Therefore,acoustic backscatter intensity surveying appears useful in the delineation and evaluation of crust resources,although further more work is needed to develop a practicable methodology.

3D joint inversion of controlled-source audio-frequency magnetotelluric and magnetotelluric data

Different geophysical exploration methods have significant differences in terms of exploration depth,especially in frequency domain electromagnetic(EM)exploration.According to the definition of skin depth,this difference will increase with the effective detection frequency of the method.As a result,when performing three-dimensional inversion on single type of EM data,it is not possible to effectively distinguish the subsurface geoelectric structure at the full scale.Therefore,it is necessary to perform joint inversion on different type of EM data.In this paper we combine the magnetotelluric method(MT)with the controlled-source audio-magnetotelluric method(CSAMT)to study the frequency-domain three-dimensional(3D)joint inversions,and we use the unstructured finite-element method to do the forward modeling for them,so that the numerical simulation accuracies of different electromagnetic methods can be satisfied.By combining the two sets of data,we can obtain the sensitivity of the electrical structure at different depths,and depict the full-scale subsurface geoelectric structures.In actual mineral exploration,the 3D joint inversion is more useful for identifying subsurface veins in the shallow part and blind mines in the deep part.It can delineate the morphological distribution of ore bodies more completely and provide reliable EM interpretations to guide the mining of minerals.

Rotational failure analysis of spherical-cylindrical shell pressure controllers related to gas hydrate drilling investigations

In situ pressure-preserved coring(IPP-Coring)technology is considered one of the most efficient methods for assessing resources.However,seal failure caused by the rotation of pressure controllers greatly affects the success of pressure coring.In this paper,a novel spherical-cylindrical shell pressure controller was proposed.The finite element analysis model was used to analyze the stress distribution and deformation characteristics of the pressure controller at different rotation angles.The seal failure mechanism caused by the rotation of the pressure controller was discussed.The stress deviation rate was defined to quantitatively characterize the stress concentration.Based on the test equipment designed in this laboratory,the ultimate bearing strength of the pressure controller was tested.The results show that the rotation of the valve cover causes an increase in the deformation on its lower side.Furthermore,the specific sealing pressure in the weak zone is greatly reduced by a statistically significant amount,resulting in seal failure.When the valve cover rotates 5°around the major axis,the stress deviation rate is-92.6%.To prevent rotating failure of the pressure controller,it is necessary to control the rotation angle of the valve cover within 1°around the major axis.The results of this research can help engineers reduce failure-related accidents,provide countermeasures for pressure coring,and contribute to the exploration and evaluation of deep oil and gas resources.

Recent progress in submarine geosciences in China

In China submarine geosciences represents a newly established discipline of oceanography, focusing on the oceanic lithosphere, and its interface with the hydrosphere and biosphere. Recently, supported by the National High Technology Research and Development Program and other high-tech development projects, significant progress has been made in the development of advanced technologies and equipment. This en- ables the scientists in China to carry out explorations of the international seabed area in the Pacific Ocean and on the Southwest Indian Ridge. In addition, they have been active in the research activities associated the mid-ocean ridges and western Pacific marginal seas. It is anticipated that this research field will continue to be highly fruitful in the near future.

Sinomine Resource Exploration Co., Ltd. Entered Lithium Raw Material Sector with Approved Acquisition and Reorganization

According to an announcement by Sinomine Resource on the evening of June 27,it received a notice from China Securities Regulatory Commission(CSRC)on June 27,indicating that the shares issuing,assets purchase by cash payment,supporting fund raising and related party transaction of Sinomine Resource

Cloud and precipitation interference by strong low-frequency sound wave

Acoustic interference of atmosphere has been an attractive research area because of its potential effect on environment,water resources,ecology,agriculture,and other areas.However,it is also a controversial topic because of the difficulty of quantitative assessment and high operating costs.In this study,a novel acoustic interference technology is proposed that uses strong lowfrequency sound waves.There is no chemical pollution or dependence on airborne vehicles,and it can be remotely controlled at low cost.A complete equipment system for acoustic atmospheric interference technology is established,based on which a series of experimental studies on cloud and precipitation response under acoustic action are performed,mainly including the radar echo intensity,cloud microphysical characteristics and the spatial distribution of ground rainfall intensity.The trigger and periodic effect of the acoustic waves on the cloud are proposed to be the key responses of acoustic atmospheric interference.This study is important to further research on atmosphere interference technology based on low frequency strong sound waves.