Strong Heterogeneity Research Articles

Deep Learning-Based Fluid Identification with Residual Vision Transformer Network (ResViTNet)

The tight sandstone gas reservoirs in the LX area of the Ordos Basin are characterized by low porosity, poor permeability, and strong heterogeneity, which significantly complicate fluid type identification. Conventional methods based on petrophysical logging and core analysis have shown limited effectiveness in this region, often resulting in low accuracy of fluid identification. To improve the precision of fluid property identification in such complex tight gas reservoirs, this study proposes a hybrid deep learning model named ResViTNet, which integrates ResNet (residual neural network) with ViT (vision transformer). The proposed method transforms multi-dimensional logging data into thermal maps and utilizes a sliding window sampling strategy combined with data augmentation techniques to generate high-dimensional image inputs. This enables automatic classification of different reservoir fluid types, including water zones, gas zones, and gas–water coexisting zones. Application of the method to a logging dataset from 80 wells in the LX block demonstrates a fluid identification accuracy of 97.4%, outperforming conventional statistical methods and standalone machine learning algorithms. The ResViTNet model exhibits strong robustness and generalization capability, providing technical support for fluid identification and productivity evaluation in the exploration and development of tight gas reservoirs.

Assessing CO2 storage potential in saline aquifers with low porosity and strong heterogeneity in Permian Shiqianfeng formation in the Yulin area, Ordos Basin: optimization based on a 3D geological model constrained by horizontal probability trend

Assessing CO2 storage potential in saline aquifers with low porosity and strong heterogeneity in Permian Shiqianfeng formation in the Yulin area, Ordos Basin: optimization based on a 3D geological model constrained by horizontal probability trend

Groundwater reserves in a mountainous headwater catchment Insights from geophysics performed on the Strengbach Critical Zone Observatory

Introduction Modelling the hydrological processes in mountainous areas is particularly challenging due to the strong heterogeneity of the underground medium in terms of hydrological properties, and the lack of groundwater observations. Here, we show how geophysical observations provide key information on the geometry of hydrofacies, the estimate of hydrological properties and the monitoring of the groundwater to study the critical zone in the Strengbach mountainous headwater catchment. Studied Site The OHGE (Observatoire Hydrogéochimique de l’Environnement) is a headwater catchment of 0.8 km² that lies on a granitic bedrock (Pierret et al. 2018). This observatory corresponds to the Strengbach catchment and is part of OZCAR, the French network of critical zone observatories. The OHGE is located in the Vosges mountains (northeastern France) with altitudes varying between 880 m and 1150 m (Fig. 1). The catchment topography shows steep slopes of 15° in average that reach up to 30° locally. Learning from scattered geophysical data Meteorological and hydrological data are monitored since 1986 and six boreholes provide the distribution of geological facies at depths of 50 to 120 m (Chabaux et al. 2023). In addition, electrical resistivity and seismic refraction tomographies were acquired to estimate variations in soil and saprolite thickness. These data show soil thickness varying from 50 cm to 5 m, and saprolite thickness ranging from 1 to 16 m (Lesparre et al. 2024). The electrical resistivity tomographies also underline the spatial distribution of the geological facies, as one slope of the catchment shows significantly higher resistivity values than the other (Lajaunie et al. 2024). Despite the relatively thin saprolite, magnetic resonance soundings detected groundwater above the noise level, and revealed a region with higher water content (Lesparre et al. 2020). Gravity data acquired across the whole catchment shows that the method has the sensitivity to distinguish areas with distinct water storage dynamics (Chaffaut et al. 2022). In particular, a region upstream the Strengbach stream exhibits the highest values of water content and the largest variations in water storage. We are using the geophysical data to develop a catchment-scale hydrogeophysical inversion. Hydrofacies geometries will be derived from the tomographies, and local hydrogeophysical experiments will be interpreted together with direct observations to estimate the range of hydrological properties. That information will serve as prior information of the inverse problem that will assimilate magnetic resonance and gravity data to complete piezometer and flow rate data.

Multifractal Analysis of Tight Sandstone Using Micro-CT Methods: A Case from the Lower Cretaceous Quantou Formation, Southern Songliao Basin, NE China

The relationships between the pore structure and a single fractal or specific region have been widely reported. However, the intrinsic relationship between multifractal parameters and physical properties have remained uncertain. In this study, micro-computed tomography scanning technology and high-pressure mercury injection technologies were applied to determine the pore structures of tight sandstone at different scales. Subsequently, the multifractal theory was applied to quantitatively evaluate the multiscale pore structure heterogeneity. An evident linear relationship exists between logXq,ε and log⁡(ε), indicating the pore structure of tight sandstones exhibits significant multifractal characteristics. Multifractal parameters, including ∆α, ∆D, Dmin−D0,and D0−Dmax, can serve as sensitive indicators to assess the multiscale pore structure heterogeneity. In particular, the relative development degree of large-scale pores (>10 μm) can be reflected by Dmin−D0 , which has strong heterogeneity. The heterogeneity of the multiscale structure is closely linked to the mineral components of tight sandstone reservoirs, and the heterogeneity of small-scale pores (1–10 μm) is stronger by clay mineral enrichment. Furthermore, the part of the pore structure corresponding to the combination of pore size range of 10 to 20 μm and throat size range of 20 to 40 μm in a low probability measure area may dominate the permeability of tight sandstone. The findings enhance the understanding of pore structure heterogeneity and broaden the application of multifractal theory.

Education training on physical activity in italian medical university courses: a call for action

Abstract Background Solid scientific evidence has demonstrated the role of physical activity (PA) as one of the most effective prevention and treatment strategies for many chronic diseases. Nevertheless, almost one third of the world population does not meet the minimum level of PA recommended by the World Health Organization, resulting in a relevant impact on healthcare systems. Tailored counseling and exercise prescription play a crucial role in addressing both the individual and economic burden of disease. These topics should thus be included in the curriculum of medical university courses as suggested by the Italian Ministerial designated and mandatory training course "Physical activity and well-being medicine". Purpose The aim of this study was to examine the level of training on PA in Italian Single-Cycle Master Degree Courses in Medicine and Surgery. Methods A cross-sectional study was conducted between December 2023 and March 2024 with an online survey administered to all 27 Directors of Italian Schools of Medical Specialization in Sports and Exercise Medicine (SEM). The survey addressed the content and modalities of curricular and elective training courses in Medicine and Surgery regarding PA and exercise prescription. Results Information from 24 medical university courses were collected. The current training on PA was considered inadequate by 83% of the responders. The amount of ECTS (European Credit Transfer and Accumulation System) credits spent on these topics was between 1 and 2 in 23 out of 24 courses, and in all cases <20 hours in a 6-year curriculum. Elective training was offered in 29% of degree programs. The most common topics included in the Syllabus of curricular courses were functional evaluation (42%), exercise prescription (33%), sports cardiology (29%) and PA in primary or secondary prevention (29%); none of these topics was included in more than 50% of the courses, emphasizing strong heterogeneity. 25% and 57% of the specific teaching in curricular and elective courses was provided by SEM specialists, respectively. The responders identified the inadequate consideration of SEM as the main obstacle to provide an appropriate training on these topics (63%). Conclusion Although the Ministry of Education designated 2-7 mandatory ECTS credits to "Physical activity and well-being medicine", the level of training in Italian degree programs is currently inadequate. This seems mainly due to the limited amount of dedicated teaching hours and to the lacking involvement of SEM in educational programs. These facts may lead to a call for action regarding a consensus on training programs about PA and its implementation in Italian medical curricula involving SEM specialists. Moreover, the heterogeneity in syllabus must be reduced and adequate basic abilities on exercise prescription provided in order that all future medical doctors graduate with such competence, likely to significantly affect the healthcare system in the long-term.

Analysis of growing season drought characteristics and driving factors for vegetation in the Santun River Irrigation Area in Xinjiang.

Global warming is exacerbating the occurrence of droughts, which have a significant impact on society. Drought is one of the main factors limiting the development of the Santun River Irrigation Area in Xinjiang. Clarifying the driving mechanism and spatial and temporal evolution characteristics of drought in this irrigation area is crucial for ensuring the sustainable development of agriculture. In this paper, the temperature vegetation drought index (TVDI) is used as a drought indicator to analyze the spatial and temporal evolution characteristics of drought in the Santun River Irrigation Area in Xinjiang, as well as to reveal the factors influencing drought using a Geoprobe model. The results show that the mean value of the TVDI in the Xinjiang Santun River Irrigation Area during 19 years was 0. 738, categorizing it as medium drought. During this period, there was an increasing trend of drought in spring and autumn and a decreasing trend of drought in summer. The drought in the irrigation district had strong spatial heterogeneity, and overall, the drought was stronger in the northern part of the region than in the southern part of the region. Over the past 19 years, the light drought areas in the irrigation district shifted to the medium and severe drought classes at a rate of 114.9 km2·10a-1. The combined effect of elevation and temperature had the strongest explanatory power for drought occurrence in the irrigated area, with a q-value of 0.869. The results of this study provide a theoretical basis for drought risk assessment and water resource planning in arid regions, as well as a reference for drought monitoring studies in similar regions.

Enhancing the Synergistic Pathways of Industrial Pollution and Carbon Reduction (PCR) in China: An Energy Efficiency Perspective

Industry is a major contributor to air pollution and CO2 emissions, and a major force for reducing them. Based on the idea of improving the performance of the synergy effect “1 + 1 > 2”, this paper constructs a method that evaluates the synergistic effect of pollution and carbon reduction (PCR) in terms of energy efficiency under the framework of Data Envelopment Analysis (DEA) and analyzes the basic path of China’s synergistic effect of PCR from the viewpoint of energy efficiency. Based on the construction of a global non-radial directional distance function, we develop an emission performance measurement index for output factors. Furthermore, by comparing performance changes under individual and collaborative emission reduction scenarios, we establish an evaluation model for assessing the synergistic effects of PCR. The results show the following: (1) Collaboration between PCR enhances both the air pollution emission performance and carbon dioxide emission performance in China. (2) The synergistic effect of collaborative emission reduction is universal in different regions and provinces. However, the synergistic effect of PCR found in the east, central, and west has strong heterogeneity. (3) Different improvement pathways, such as prioritizing energy conservation or carbon mitigation, were designed to account for regional development disparities. Although these policy orientations can effectively enhance the synergy between pollution control and carbon mitigation, the extent of improvement varies considerably across regions.

Exploration of the pharmacological substance basis and efficacy evaluation of fufang she-she-cao (Hedyotis diffusa formula) in repressing gastric cancer.

Exploration of the pharmacological substance basis and efficacy evaluation of fufang she-she-cao (Hedyotis diffusa formula) in repressing gastric cancer.

High‐Resolution Lithospheric Shear Velocity Structure of the Suqian Segment of the Tanlu Fault Zone From Ambient Noise Tomography

AbstractTo understand causes of the Suqian seismic gap and the 1668 M8.5 Tancheng earthquake, we determine a new 3‐D S‐wave velocity (Vs) model of the lithosphere under the Suqian segment of the Tanlu fault zone in eastern China using ambient noise tomography. Rayleigh wave phase velocity dispersions at periods of 5–33 s are collected from seismograms recorded at our newly deployed TanluArray portable stations and permanent provincial seismic stations in and around the Suqian area. The addition of the TanluArray data leads to much higher tomographic resolution in the study region. Our model well depicts surface geological features and reveals strong lateral heterogeneities in and around the fault zone. Beneath the Suqian seismic gap, the upper crust and uppermost mantle show low‐velocity anomalies, whereas the middle and lower crust exhibit high‐velocity anomalies. Such a structure in the Suqian area may hinder the accumulation of tectonic stress, leading to the formation of a seismic gap. The Tancheng earthquake occurred in a transition zone between high‐ and low‐Vs anomalies in the middle crust, which is prone to stress accumulation and earthquake nucleation. The Tanlu fault zone serves as a channel for hot and wet mantle material upwelling into the crust, where fluids reduced the threshold for fault rupture and so triggered the Tancheng earthquake. The mantle upwelling may be related to dynamic processes in the big mantle wedge associated with stagnation and dehydration of the subducted Pacific slab in the mantle transition zone under East Asia.

Current status, potential assessment, and future directions of biological treatments of unconventional oil and gas wastewater.

Current status, potential assessment, and future directions of biological treatments of unconventional oil and gas wastewater.

Mapping the Impact of Spontaneous Streetscape Features on Social Sensing in the Old City of Quanzhou, China: Based on Multisource Data and Machine Learning

Streetscapes in old urban areas are not only an important carrier to show regional economies and city style, but also closely correlate to urban residents’ everyday life and the hustle and bustle in which they live. Nevertheless, previous studies have either focused on a few examples with low-throughput surveys or have lacked a specific consideration of spontaneous features in the data-driven explorations. Furthermore, the impact of spontaneous streetscape features on diversified social sensing has rarely been examined. This paper combined the mobile collection of street view images (SVIs) and a machine learning algorithm to calculate eight types of spontaneous streetscape elements and integrated two online platforms (Dianping and Sina Weibo) to map the distribution of economic vitality and social media perception, respectively. Then, through comparing multiple regression models, the impacts of the spontaneous streetscape characteristics on social sensing were revealed. The results include the following two aspects: (1) overall, the spontaneous streetscape features have a certain similarity in the impact on both dimensions of social sensing in Quanzhou, with significant clustering and transitional trends and strong spatial heterogeneity; and (2) specifically, the spontaneous streetscape elements can be divided into three categories, given the differentiated roles of significantly positive, negative, and polarizing impacts on the social sensing results. For example, proper use of open-interface storefronts, ads, and banners is consistent with the common suggestions, while the excessive pursuit of interface diversity and the use of cultural elements may bring an ambiguous effect. This paper provides a transferable analytical framework for mixed and data-driven sensing of streetscape regeneration and can potentially inspire related decisionmakers to adopt a more refined and low-cost approach to enhance urban vitality and sustainability.

Comparison of efficacy between micro-osteoperforations and alveolar corticotomies on the rate of orthodontic tooth movement: A systematic review and meta-analysis.

Comparison of efficacy between micro-osteoperforations and alveolar corticotomies on the rate of orthodontic tooth movement: A systematic review and meta-analysis.

XGBoost algorithm optimized by simulated annealing genetic algrithm for permeability prediction modeling of carbonate reservoirs

Carbonate reservoir has strong heterogeneity, complex pore structure and poor correlation between porosity and permeability, so the traditional permeability model can not meet the needs of logging interpretation. Taking the carbonate reservoir of Longwangmiao Formation in Moxi block of central Sichuan as an example, this paper proposes to establish a permeability prediction model by using the XGBoost algorithm of simulated annealing genetic algrithm (SA-GA)hybrid optimization. Combined with core data, five permeability sensitive logging curves (CNL, DEN, DT, and GR) are optimized by calculating correlation coefficients, and the permeability prediction model is established based on XGBoost algorithm, and the XGBoost hyperparameters are optimized by using SA-GA. The method is applied to the evaluation of logging permeability in the study area. The results show that the prediction results of SA-GA-XGBoost algorithm are more consistent with the core data. The adjusted is 0.876, and the root mean square error (RMSE) is only 0.142. The prediction accuracy is better than the conventional permeability model and BP neural network model, which meets the industrial requirements of logging evaluation and provides a new idea for oil and gas exploration in carbonate reservoirs.

Modelling Pressure Dynamic of Oil–Gas Two-Phase Flow in Three-Zone Composite Double-Porosity Media Formation with Permeability Stress Sensitivity

In view of the flow zoning phenomenon existing in condensate gas reservoirs and the complex pore structure and strong heterogeneity of carbonate rock reservoirs, this study investigates the pressure dynamic behavior during the development process of such gas reservoirs by establishing corresponding models. The model divides the reservoir into three zones. The fluid flow patterns and reservoir physical property characteristics in the three regions are different. In particular, the fracture system in zone 1 has permeability stress sensitivity. The model is solved and the sensitivity analysis of the key parameters is carried out. The research results show that reservoir flow can be divided into 12 stages. Stress sensitivity affects all stages except the wellbore storage stage and becomes increasingly obvious over time. The closed boundary causes fracture closure from the lack of external energy, reducing effective flow channels and triggering the boundary response stage earlier. The increased condensate oil increases the flow resistance and pressure loss, and shortens the duration of the flow stage. The research suggests that improving reservoir conditions and enhancing fluid fluidity can reduce pressure loss and increase production capacity, providing valuable theoretical and practical guidance for the development of carbonate rock condensate gas reservoirs.

Research Progress and Challenges of Shale Oil Reservoir Characteristics

This article systematically reviews the latest progress and main challenges in the research of shale oil reservoir characteristics. As an important unconventional oil and gas resource, the study of shale oil reservoir characteristics is of great significance for resource evaluation and development. The article elaborates in detail on the main characteristics of shale oil reservoirs from five aspects: geological features, physical properties, geochemical features, mechanical properties, and development characteristics. It analyzes the key issues and challenges in current research and looks forward to future research directions. The research shows that shale oil reservoirs have typical low porosity and low permeability characteristics, with well-developed nanoscale pores, strong reservoir heterogeneity, and are controlled by multiple geological factors. Future research should focus on multi-scale characterization techniques, digital core technology, and the application of artificial intelligence to promote the efficient development of shale oil.

Characterization of Dolomite Reservoir Pore‐Throat Structure Based on Cast Thin Section Image Analysis and Fractal Theory: A Case Study of Middle Jurassic Dolomite in the Southern Depression of Qiangtang Basin, Northern Tibetan Plateau, China

ABSTRACTThe Middle Jurassic Buqu Formation dolomite in the Qiangtang Basin, northern Tibetan Plateau, is characterized by strong heterogeneity, low porosity, and low permeability, making the evaluation of its pore structure a challenging task. In this study, dolomite samples were extracted from boreholes and examined using cast thin sections and scanning electron microscopy. Combined with petrophysical analysis, we investigated the distribution and fractal characteristics of the pores, and explored the relationship between the fractal dimension and reservoir petrophysical parameters, pore structure parameters, and pore genesis. The results indicate that: (1) The types of storage spaces in the Buqu Formation dolomite in the study area include selective intercrystalline pores, nonselective intercrystalline pores, and fractures, with a relatively concentrated pore size distribution. (2) The R² of the fractal fitting curve of the large pore equivalent mercury injection is greater than 0.95, indicating that the large pores of the dolomite reservoir exhibit fractal characteristics, which can be used to characterize the pore structure. The pores are complex and diverse, with strong interlayer (overall) heterogeneity. (3) The fractal dimension of large pores has a good correlation with petrophysical parameters and pore structure parameters, and can be used for the quantitative characterization of the pore structure of the Buqu Formation dolomite reservoir. (4) The pores of carbonate sediments formed by sedimentation are the basis of the storage space and pore‐throat structure of this set of reservoirs, and the subsequent dolomitization and dissolution processes jointly control the heterogeneity of the pore‐throat structure.

Information extraction and characteristic analysis of cultivated land abandonment in karst rocky desertification mountainous areas based on time-series vegetation index

Due to the influence of rocky desertification, the phenomenon of abandoned farmland is serious in karst mountainous areas. The accelerated urbanization process, the transfer of rural labor force, and the obstruction of agricultural mechanization have aggravated the abandonment of cultivated land. Curbing the large-scale abandonment of cultivated land is of great significance to regional food security and sustainable agricultural development. Taking a typical karst rocky desertification mountainous area as an example, using Sentinel-2 A remote sensing images, the NDVI time series change detection coupling joint detection method was used to extract the abandoned land in Guanling County from 2019 to 2022, and its desertification degree and spatial heterogeneity were analyzed. The results show that: (1) The OA of the identification results of abandoned land and non-abandoned land from 2019 to 2022 is 0.86, and the Kappa coefficient is 70%, with good identification effect; (2) The abandoned area in Guanling County continued to increase from 2019 to 2022, but most of them were abandoned for two to three years, and a few were abandoned for four years. There were phenomena of recultivation and sudden abandonment of farmland; (3) Abandonment mostly occurred under conditions of no obvious desertification, mild desertification and moderate desertification, and the abandonment rate gradually decreased with the increase of desertification; (4) The abandoned land in Guanling County was mainly distributed in the direction of “northwest-southeast”, with high fragmentation, low spatial aggregation and strong heterogeneity. The study extracted information on abandoned farmland in karst desertification mountainous areas to provide a data basis for food security and protection of farmland quantity.

Gas adsorption analysis of pore structure differences and influencing factors in coal with varying metamorphic grades

The heterogeneity structural characteristics of the pores in the coal matrix largely determine the storage and transport capacity of gas. In order to quantitatively characterize the pore structure in coal matrix and analyze the influencing factors, the filled pores (0.38–1.5 nm) and diffusion pores (1.5–100 nm) of seven coal samples with different metamorphic degrees were measured by low-temperature liquid nitrogen adsorption and carbon dioxide adsorption experiments, and combined with the theory of multifractality, the filled pores and adsorbed pores of coal samples with different degrees of metamorphism were characterized and discussed. The multiple fractal characteristics and influencing factors of the filled and adsorbed pores of coal samples with different metamorphic degrees were characterized and discussed. The results show that both diffusion pores and filled pores have multiple fractal characteristics; the more metamorphism, the more developed the filled pores and the stronger the heterogeneity. High-order coals had a strong heterogeneity of diffusion pores, while low-order coals exhibited a strong heterogeneity of filled pores. The heterogeneity of filled pores was negatively correlated with specific surface area and pore volume, while the opposite was true for diffusion pores. The relationship between pore heterogeneity and fixed carbon content showed a “U” distribution.

Study on main controlling factors of sandstone reservoir unsteady water drive development

Abstract In order to identify the main controlling factors affecting the unsteady water drive development, a conceptual model considering planar heterogeneity is established by using numerical simulation software. The main controlling factors affecting the unsteady water drive development are analyzed based on the numerical model. The geological factors mainly analyzed are planar heterogeneity, permeability, and crude oil viscosity. While the development factors are mainly analyzed from the aspects of recovery degree, pressure retention level, and water cut rise rate. The results show that the development effect of an unsteady water drive is better than that of a conventional water drive for reservoirs with strong heterogeneity. Unsteady water drive development is more suitable for reservoirs with strong heterogeneity, low permeability, low oil viscosity, high-pressure retention level, low recovery degree, and high water cut rise rate. Considering the reservoir selecting technical limits for unsteady water drive development, the H34 fault block is suitable for unsteady water drive development, which provides a theoretical basis for subsequent unsteady water drive development.

Does Medication Status Impact the Effectiveness of Nuts in Altering Blood Pressure and Lipids? A Systematic Review and Meta-Analysis.

Nut consumption is attributed to improvements in risk factors for cardiovascular disease (CVD), including high blood pressure (BP) and dyslipidemia. However, it is unclear whether these effects are altered with concurrent treatment with BP and lipid-lowering medication. We sought to investigate the effects of the consumption of whole tree nuts and peanuts (collectively termed nuts) on BP and lipids, and whether BP and lipid-lowering medication use alters these effects. The MEDLINE, EMBASE, Scopus, and Web of Science databases were systematically searched through June 21, 2023, for randomized controlled trials (RCTs) assessing the effects of nut consumption on BP and/or lipids. Random effects meta-analyses (mean difference, 95% confidence interval [CI]) were conducted, with subgroup analyses based on reported participant use of BP or lipid-lowering medication, including medicated, unmedicated, unreported (ie, use not specified), and mixed (ie, included combined data from medicated and unmedicated participants). A total of 115 studies were included in the review, of which 109 were meta-analysed. Nut consumption significantly reduced triglycerides (TG), total cholesterol, low-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, and apolipoprotein B, with no effect on high-density lipoprotein cholesterol or blood pressure. Few studies were conducted in medicated participants only (n = 1 for lipid outcomes only), and for the studies including both medicated and unmedicated participants (ie, mixed), outcomes by medication use were not reported. Significant differences in TG and apolipoprotein B were observed between medication use groups, with nut consumption resulting in the largest reductions in unmedicated participants. Strong heterogeneity was observed with no evidence of publication bias. Lipid-lowering, but not BP-lowering benefits of nut consumption were observed; however, few studies reported the effect based on participants' medication status. Future studies are required to determine if there are additional benefits of including nuts in the diet of medicated patients with cardiovascular disease. PROSPERO registration code CRD42022296849.