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To address the prevailing scenario where comprehensive susceptibility assessments of ground deformation disasters primarily rely on knowledge-driven models, with weight judgments largely founded on expert subjective assessments, this study initially explores the feasibility of integrating data-driven models into the evaluation of urban ground collapse and subsidence. Hangzhou city, characterized by filled soil and silty sand, was selected as the representative study area. Nine pertinent evaluation factors were identified, and the RF-BP neural network coupling model was employed to assess the susceptibility of ground collapse and subsidence in the study area, the results indicate that the stacked model achieved a 7% increase in AUC value compared to the single model. Subsequently, this study utilized the advanced large language model (LLM), ChatGPT-4, to supplant expert judgment in the weight determination of ground deformation disasters. The advantages of ChatGPT-4, such as its ability to process vast amounts of data and provide consistent, unbiased judgments, were highlighted. ChatGPT-4's assessments were validated by geological experts in the study area through the analytic hierarchy process. The results show that, by analyzing the same textual materials, the weights determined by experts differed by only 3% from those judged by ChatGPT, demonstrating the reliability and human-expert-like logic of ChatGPT-4's judgments. Finally, a comprehensive susceptibility assessment of ground deformation disasters was conducted utilizing ChatGPT-4's judgment results, yielding favorable outcomes. [ABSTRACT FROM AUTHOR]

An investigation of the distribution and control factors of groundwater is significant for the rational exploitation and utilization of groundwater resources. This study analyzes the hydrogeochemical processes and control factors of shallow groundwater in the Guohe River Basin. A hydrogeological survey was conducted, and hydrochemical and hydrogen–oxygen isotopic data of 125 samples of surface water and groundwater were analyzed. The results showed that the total dissolved solid (TDS) content in shallow groundwater was 138–2967 mg/L, with an average of 831 mg/L. A decline in the TDS was observed from the upper to the lower reaches. The contents of the anions and cations in the shallow groundwater were in the order HCO3− > Cl− > SO42− and Na+ and K+ > Mg2+ > Ca2+, respectively. The cation exchange increased the aqueous concentrations of Na+ and K+, and the TDS content was highly correlated with the contents of Na+, Cl−, and SO42− ions. The δD and δ18O values in shallow groundwater increased from the upper to the lower reaches, with the mean δD values being −59.72‰, −53.58‰, and −47.17‰ and the mean δ18O values being −8.33‰, −7.37‰, and −6.43‰. The contribution rates of the recharge source, evaporation, and water–rock interaction to the groundwater TDS concentration were 20.4%, 29.5%, and 50.1%, respectively. The water–rock interaction dominated the formation of shallow groundwater in the Guohe River Basin. The dissolution of salt rock and gypsum contributed to ion formation in shallow groundwater. The research findings can be used to improve the groundwater quality in the Guohe River Basin. [ABSTRACT FROM AUTHOR]

The chronological framework of late Pleistocene and Holocene transgressional strata along the Fujian coasts in southeastern China were examined using new 14C dates, OSL ages, and diatom data from cores drilled in Longhai. This location was chosen because previous studies in the region have interpreted the occurrence of MIS3, MIS2, and Holocene transgressions. Our study, and a critical review of previous studies, show that 14C dates of bulk samples from coastal areas tend to be erroneously older than the depositional age due to enhanced input of old carbon via erosion of Mesozoic basement rocks from mountainous inlands. Also, OSL dates of deltaic and fluvial sediments either vary widely due to unsuitable luminescence properties of quartz grains or tend to be older than true depositional ages due to partial bleaching. As such, the previously considered late Pleistocene transgression may have occurred in the Holocene. Overall, the early Holocene transgression is well documented along Fujian coast revealing largely consistent early Holocene sea level histories from northern and southern sectors of Fujian coast. However, late Pleistocene transgressions are not well preserved along Fujian coasts, likely due to pervasive erosion. Our examination of the chronology of transgression in Fujian coast suggests cautions for 14C dating of bulk samples and for OSL dating of sediments in fluvial-deltaic settings, and emphasizes the importance of establishing a reliable chronological framework for understanding relative sea level history in this region and in similar settings elsewhere. [ABSTRACT FROM AUTHOR]

The ground-coupled ground-source heat pump (GSHP) system is a common method for shallow geothermal energy exploitation and utilization. GSHP has a great heat exchange rate and wide application range. In order to effectively exploit shallow geothermal energy in the central urban area of Danyang City, Jiangsu Province, based on finite volume method, it is adopted to simulate the amount of recoverable shallow geothermal energy in the study area through ground-coupled heat exchange. The simulation is conducted on the development trend of thermal transport and thermal balance in the study area from early June 2015 to the end of May 2025 to obtain the temperature distribution at different times. Under the presupposed working conditions, with the operation of a ground-coupled GSHP, thermal accumulation occurs in parts of the study area. To mitigate the problem of thermal accumulation, two schemes are proposed: (1) adding auxiliary cooling towers and (2) increasing the amount heated domestic water in spring and autumn. Both schemes mitigate thermal accumulation. For Scheme  1, the total heat supply for shallow geothermal energy in the central urban area of Danyang City in winter is 2.91 × 106 kW, and the total heat release in summer is 3.53 × 106 kW. For Scheme  2, the total heat release in summer is 3.52 × 106 kW and the total heat supply in winter is 2.90 × 106 kW. A ground-coupled GSHP system has significant applicability in the central urban area of Danyang City, where shallow geothermal energy has good exploitation prospects. [ABSTRACT FROM AUTHOR]

To enhance the resilience of Nanchang’s water supply system and ensure a dependable emergency water supply. Taking youkou emergency groundwater source field as an example, a flow simulation model was developed through an analysis of the hydrogeological conditions in the study area. Additionally, an optimization model based on the genetic algorithm (GA) technique was constructed and integrated into the flow simulation model. Subsequently, various water supply schemes were simulated with the minimum cost of groundwater extraction as the objective function. The results show that the values of the objective function were reduced by 4.92%, 15.67%, and 42.35% for the three different optimization schemes, namely pumping rates, joint pumping rates and the number of wells, and joint pumping rates, number of wells and well location. Ultimately, the optimal emergency water supply scheme was determined by considering a comprehensive range of factors. These factors encompassed considerations such as the area of the water level depression funnel, the dewatering thickness of the aquifer and the recovery of the groundwater level. The practice shows that the simulation–optimization model could effectively simulate complex groundwater flow systems, meeting the objective function and constraints toachieve the optimal exploitation scheme. [ABSTRACT FROM AUTHOR]

Coastal engineering construction suitability evaluation methods are too empirical and difficult to quantify. Considering these weaknesses, in order to determine the weight of each factor reasonably, and to analyze the suitability of coastal zone construction comprehensively, the theory of establishing a coastal zone construction suitability evaluation model based on a Rough Set (RS) and an Analytic Hierarchy Process (AHP) is proposed. In total, 20 typical coastal areas of Putian are selected, and the main impact factors are determined according to a port dock, pollution-prone industry, and an electric power plant. The contribution rate and weight of each factor for the construction of a coastal zone are analyzed by the combination evaluation model, and the final evaluation result is consistent with the actual investigation situation. Finally, 52 evaluation units of the Putian coastal zone are evaluated by Neural Networks (NNs). The weight of the impact factors is made more objective by using the training sample set of the combination evaluation model as the sample set of the neural network. The learning speed and accuracy of the network are improved, and the and the evaluation result is consistent with the actual investigation situation. In a word, it is effective to perform the suitability evaluation of the coastal zone construction using the RS-AHP-NN proposed model, and it can be applied in practical engineering. [ABSTRACT FROM AUTHOR]

Now ground source heat pump is a more efficient way to develop and utilize shallow geothermal energy because it is clean and environmentally friendly and has a relatively low energy cost. In order to optimize the planning layout and geographical space development in the eastern new town of Anqing city, which can realize the transformation and upgrading of real space and urban sustainable development, the exploration for shallow geothermal energy will be carried out in this area, so as to find out the comprehensive thermophysical parameters of the shallow rock-soil body and the heat transfer capacity of the vertical heat exchanger, etc. This paper takes the CBD in the eastern new town of Anqing as an example to provide the basis for the feasibility construction of the ground source heat pump project in the study area and evaluate the economic and environmental benefits of the expected project. According to the simulation test data of 5 working conditions of 4 geothermal exploration holes in the study area, we can clearly know that the energy cost per square meter of the ground source heat pump is 11.8 yuan for a building of one hundred thousand square meters in which the heat removal power is expected to be 9481 kW in summer and 3070 kW in winter. And the annual emission of carbon dioxide, sulfur dioxide, nitrogen oxides, suspended dust, and other air pollutants to the atmosphere can be reduced by 1442.5 t, and the solid waste ash and slag can be reduced by 59.7 t. The annual environmental treatment cost will be saved by 166000 yuan. [ABSTRACT FROM AUTHOR]

The Jiangnan Orogen is located at a key tectonic position along the junction between the Yangtze and Cathaysia blocks. We obtained detailed major and trace elements, whole-rock Nd + zircon Hf isotope data, and U–Pb age data from several Mesozoic granites, including the Fuling (FL), Taiping–Huangshan (TH), Lingshan (LS), Sanqingshan (SQS), and Baijuhuajian intrusions in order to investigate their sources and petrogeneses related to extension in South China. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analyses of zircon from the FL, TH, SQS, and LS bodies yield Early Cretaceous ages of 124–135 Ma. These plutons are alkali-feldspar granites to syenogranites–monzogranites, and show A-type affinities. They have high K2O and total alkali contents, and are enriched in rare earth elements (except for Eu), Zr, and other high-field-strength elements as well as high Ga/Al ratios, and are depleted in Ba and Sr. These granites are metaluminous to weakly peraluminous (ACNK from 0.81 to 1.27). The whole-rockϵNd(T) values of −5.34 to −0.96 are coupled with zirconϵHf(T) values (from −5.3 to +4.24), and all samples plot along the mantle array. Field observations, geochronology, geochemistry, Nd isotopic, and zircon Hf isotopic compositions suggest that they formed by the partial melting of Mesoproterozoic metamorphic basement, with input from juvenile, mantle-derived materials in the shallow (<30 km) crust at high temperatures (756–965°C). These melts underwent crystal fractionation of biotite, plagioclase, and K-feldspar. The upwelling of asthenosphere triggered partial melting of the metamorphic protolith in a back-arc or intra-arc rift setting, reflecting rollback of the Pacific plate. Our research adds new geochronologic constraints on Cretaceous (135–120 Ma) A-type granites from the NE sector of the Jiangnan Orogen. Combined with previous research, we suggest that three main episodes of late Mesozoic extensional tectonism took place in South China: (1) 190–170 Ma (mainly inland), (2) 165–120 Ma (including 165–150 Ma in SE Shi-Hang, 135–120 Ma in NE Shi-Hang, and ∼125 Ma in the Lower Yangtze River Belt), and (3) 100–90 Ma (coastal area), showing an oceanwards younging trend due to the subduction of the Palaeo-Pacific plate. [ABSTRACT FROM AUTHOR]

• Framework of UUS geological suitability evaluation in 3D (3D-UGSE) is proposed. • Implicit method enables fast automatic generation of underground geological bodies. • 3D spatial analysis methods extract more evaluation factors via data integration. • 3D-UGSE framework gives more evaluation results and enhances down-depth resolution. Geological suitability evaluation for urban underground space (UUS) is essential for effective UUS utilisation and exploitation risk reduction. However, previous research was hampered by limited availability of 3D technology. The 2D data-based evaluation process has led to information loss among underground data, whilst evaluation results without 3D attributes would also impede accurate analysis and further application. This study presents a novel UUS geological suitability evaluation (3D-UGSE) framework, which accounts for the characteristics of 3D data and other practical requirements. The framework integrates a large amount of available geoscientific data with 3D technology, and contains five steps: (1) data collection and integration; (2) 3D geological model construction using implicit 3D geological modelling method with multi-source geological data; (3) 3D evaluation index system creation, considering local geological conditions based on the available data; (4) 3D thematic map production from the 3D geological models, using 3D spatial analysis methods; (5) 3D geological suitability map production, integrating all the 3D thematic maps using comprehensive evaluation methods. To evaluate this approach, we took the Qianjiang Newtown in Hangzhou (eastern China) as an example and assessed the UUS geological suitability in three dimensions. The results show that the 3D-UGSE framework can effectively integrate 2D and 3D geological information, give more reasonable and informative evaluation results, and enhance the depth resolution of the results. This approach can provide more useful information for the planning, sustainable development, and utilisation of urban underground space. [ABSTRACT FROM AUTHOR]