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Faults play a pivotal role in controlling fluid migration and retention within sedimentary basins, particularly in the context of fault-bound hydrocarbon reservoirs. Assessing the stability and sealing capabilities of faults enhances our comprehension of these systems and aids in the identification of pathways for fluid migration. In this study, we focus on a series of fault-bound hydrocarbon accumulations located in the southern Wenchang A subbasin within the Pearl River Mouth Basin. We emphasize the significant influence of faults in governing the processes of hydrocarbon migration and accumulation. By leveraging 3D seismic data and well information, we have assessed the sealing potential of ten faults that either currently retain hydrocarbon columns or have the potential to do so. Our analysis reveals that even faults with a relatively low Shale Gouge Ratio (as low as 15%) can effectively support substantial column heights. Taking into account factors, such as the source rock maturity, fault activity, geometry, sealing potential, and the distribution of hydrocarbon accumulations, we have formulated a conceptual model for hydrocarbon migration and accumulation within the study area. This model underscores potential fluid traps within the rift basin, shedding light on the complex dynamics of hydrocarbon movement in this region. [ABSTRACT FROM AUTHOR]

Beach ridges are depositional features that allow reconstruction of past sea-level variations, sediment dynamics, and storm activity. However, there are still very few systematic studies focusing on beach ridges available from the Gulf of Thailand. Along the east coast, satellite images provide evidence of beach ridges in the Chanthaburi Province, extending as far as 6 km inland, oriented parallel to the current coastline. These can be divided into a set of landward ridges (5.3–6.0 km inland) and seaward ridges (0.4–1.8 km inland) that are separated by an arm of the Chanthaburi estuary. Optically stimulated luminescence dating of 26 sand samples from 12 pits of ridge profiles suggests that the landward set of beach ridges formed ca. 3500 yr ago, while the seaward set of ridges formed between ca. 2100–1200 years ago, which also includes the modern active beach. It appears that the landward set of beach ridges developed during a period of relatively stable sea level followed by a rapid regression presently occupied by the arm of the Chanthaburi estuary. The seaward set of beach ridges apparently reflects a millennium of slowly retreating coastline until the modern beach ridge formed. [ABSTRACT FROM AUTHOR]

Extracting shallow geothermal energy using borehole heat exchangers (BHEs) can help decarbonising the residential heating sector, particularly where no other low-carbon heating solutions are readily available. To assist urban planners and policy makers in developing carbon-neutral heating plans, the regional technical shallow geothermal potential must be known. Here, we calculate the technical geothermal potential of BHE fields on a regional scale while taking potential thermal interference between BHEs, geological conditions, as well as space available for BHE installation into account. The number of BHEs placed is maximized and heat extraction rate from each BHE is optimized taking regional regulations into account. When the methodology is applied to the German state of Baden-Württemberg on a building-block scale, results suggest an annual technical potential of 33.5 TWh. We then link this technical geothermal potential to heating demand scenarios on a building block scale and the results show that, depending on the renovation status of the buildings, between 44% and 93% of all building blocks can be heated using only BHEs. This allows for a rapid identification of building blocks for which BHEs are not able to meet the heating demand and where other means of heat supply will be needed. • Estimation of the regional technical shallow geothermal energy potential. •Technical geothermal potential of the German state Baden- Württemberg is presented. •Technical shallow geothermal potential is linked to regional heating demand scenarios. •Areas where borehole heat exchangers can supply heating are identified. [ABSTRACT FROM AUTHOR]

Travertine deposits at the St. Johns Dome natural CO2 reservoir in Arizona, USA, document a long (>400ka) history of surface leakage of CO2 from a subsurface reservoir. Travertine deposits are concentrated along surface traces of faults implying that there has been a structural control on the migration pathway of CO2 rich fluids. Here, for the first time, we combine slip tendency and fracture stability to analyse the geomechanical stability of the reservoir-bounding Coyote Wash Fault for three different stress fields and predict areas with high leakage risks. We find that these areas coincide with the travertine deposits on the surface indicating that high permeability pathways as a result of critically stressed fracture networks exist in both fault damage zones and around a fault tip. We conclude that these structural features control leakage. Importantly, we find that even without in-situ stress field data the known leakage points can be predicted using geomechanical analyses, despite the complex tectonic setting. Thus, even though acquiring high quality stress field data for secure subsurface CO2 or energy storage is a must, a first order assessment of leakage risks during site selection can be made with limited stress field knowledge. [ABSTRACT FROM AUTHOR]

Summary: Background and objectives: Rising numbers of patients consulting emergency units are associated with an increased demand for material and personnel. In order to better quantify these resources, we performed an analysis of diagnostic procedures, treatment types, and the quantity and educational level of staff involved in emergency consultations. Patients and methods: The study was conducted as a prospective single‐center survey over twelve months in the dermatology unit of a Germany university hospital. 3155 consultations were included by consecutive sampling. Results: Diagnostic tests (e.g. microbiological swab, blood testing, punch biopsy) were performed in 29 % of all consultations. Physicians prescribed treatment in 70 % of cases, with steroids and antihistamines being the most frequent topical and systemic treatment, respectively. Each patient was seen by at least one physician and a nurse, and in 25 % of cases an additional physician was involved. Less than thirty minutes was required for the consultation in the vast majority of cases. On average, emergency consultations required two hours per day of the treating physician's time, not including the time of other involved staff such as nurses and laboratory technicians. Conclusions: This study demonstrates the extent of resources involved in the treatment of dermatological emergency consultations. [ABSTRACT FROM AUTHOR]

Copyright of Journal der Deutschen Dermatologischen Gesellschaft is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Faults can act as barriers to fluid flow in sedimentary basins, hindering the migration of buoyant fluids in the subsurface, trapping them in reservoirs, and facilitating the build-up of vertical fluid columns. The maximum height of these columns is reliant on the retention potential of the sealing fault with regards to the trapped fluid. Several different approaches for the calculation of maximum supported column height exist for hydrocarbon systems. Here, we translate these approaches to the trapping of carbon dioxide by faults and assess the impact of uncertainties in (i) the wettability properties of the fault rock, (ii) fault rock composition, and (iii) reservoir depth on retention potential. As with hydrocarbon systems, uncertainties associated with the wettability of a CO2 –brine–fault rock system for a given reservoir have less of an impact on column heights than uncertainties of fault rock composition. In contrast to hydrocarbon systems, higher phyllosilicate entrainment into the fault rock may reduce the amount of carbon dioxide that can be securely retained due a preferred CO2 wettability of clay minerals. The wettability of the carbon dioxide system is highly sensitive to depth, with a large variation in possible column height predicted at 1000 and 2000 m of depth, which is the likely depth range for carbon storage sites. Our results show that if approaches developed for fault seals in hydrocarbon systems are translated, without modification, to carbon dioxide systems the capacity of carbon storage sites will be inaccurate and the predicted security of storage sites erroneous. [ABSTRACT FROM AUTHOR]

Copyright of Journal der Deutschen Dermatologischen Gesellschaft is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Background and Objectives: Recently, there have been increasing numbers of patients consulting emergency units in all medical disciplines. Our aim was to analyze the demographics, referral mode, symptoms, localization of lesions, prior treatment, diagnoses and hospitalization rate of dermatological patients. Patient and Methods: The study was conducted as a prospective single center survey over six months in the dermatology unit of a university hospital in Germany. 1552 consultations were included with consecutive sampling. Results: The study cohort had a mean age of 41 years and included 53 % females. Nearly half of the patients lived less than 10 kilometers from the study center. 72 % of patients referred themselves. The main symptoms were itching and occurrence of a rash; these symptoms had been present for more than a week on average. A general manifestation was present on the skin in most cases. 55 % of patients were seen by a dermatologist or a general practitioner before the consultation. Prior treatment had been received in 49 % of cases. Eight percent of patients were hospitalized. Eczema was the most common diagnosis, followed by urticaria and scabies. Conclusions: This study confirms that a considerable number of patients present with non‐urgent diagnoses. Careful prescreening and sensitization of the population may be necessary to reverse this trend. [ABSTRACT FROM AUTHOR]

Abstract: Natural CO2 reservoirs have similar geological trapping mechanisms as required for CO2 storage sites and often have held CO2 for a geological period of time without any indication of leakage. Yet, migration of CO2 from reservoirs to the surface is also common. 49 natural CO2 reservoirs have been analysed to provide an overview of factors that are important for (1) retention of CO2 in the subsurface and (2) leakage of CO2 from the reservoir. Results indicate that overpressure of the overburden and the state of CO2 in the reservoir influence the likelihood of migration and hence the performance of reservoirs. [Copyright &y& Elsevier]

Laser diffraction spectrometry allows for efficiently obtaining high-resolution grain size data. However, pretreatment and dispersion of aggregates in sediment samples are essential pre-requisites for acquiring accurate results using this method. This study evaluates the effectiveness of five dispersing agents in deflocculating the investigated fluvial sediments and the resulting grain size distribution obtained by laser diffraction spectrometry. We also examine the ability of the different dispersing agents to deflocculate sediment samples treated by thermal combustion. Distilled water presented a low efficiency in deflocculating the samples and yielded a near-zero clay content for samples with an expected clay content. The other chemical dispersants were effective in dispersing aggregates and yielding clay, albeit with different efficiencies. Calgon had the highest dispersing ability, followed closely by sodium tripolyphosphate. The performance of chemical treatment with sodium oxalate approaches that of sodium tripolyphosphate. However, it leads to the formation of precipitates in the samples, obscuring the actual grain size data. Sodium pyrophosphate derived the least amount of deflocculation among the four chemical dispersants. Furthermore, all the chemical dispersants were found to be ineffective in dispersing aggregates in samples treated by thermal combustion.