Karst geology is widely distributed in China; the great differences in natural conditions bring it an array of characteristics in different regions. There is a huge area of the buried karst in Wuhan, ...exhibiting a unique, but complicated engineering geological environment. This paper summarizes the geological conditions in Wuhan, with special focus on its karst geology. At present, a total of six karst belts have been detected, and they were divided into five structure types. For shield tunnelling in karst region, some problems such as water ingress or mud inrush, partial ground collapse, damage or failure of shield machine, and metro operation and management issues may be raised as a result of the activity of the karst geology. To prevent occurrence of possible hazards, a series of countermeasures suggested for hazard and risk mitigation were discussed in this paper. A case history, where the study section belongs to the Wuhan metro line 6, is referred to evaluate effectiveness of the adopted treatment measures. The feedbacks demonstrated that water ingress was successfully avoided, and ground deformation was effectively controlled in the study section throughout the construction phase. This study can provide significant reference information and experience for metro tunnel constructed in karst region.
From a global perspective, karst geological disaster has great influence on the tunnel construction. Once it is not handled properly, the karst problems in the tunnel area will cause great disaster, ...such as water inrush, mud gushing and collapse, etc. These karst disasters seriously affect the construction progress of the tunnel, resulting in equipment damage, casualties, and so on. The construction of Yichang–Wanzhou (YW) railway tunnel has created a miracle in the field of Chinese tunneling. The geology of tunnel area is quite complex, the karst disaster is remarkable, and the engineering construction is extremely difficult. In this paper, the karst characteristics, unfavorable geological disasters, and treatment methods of YW railway tunnel were analyzed systematically. The YW railway tunnel and Zhengzhou–Wanzhou (ZW) railway tunnel are both located in the Qinling-Daba (QB) mountainous area, and the regional geological conditions of them are very similar. Therefore, the research in this paper can be extended to the QB mountainous area, thus providing a reference for the construction of ZW railway tunnel. The investigation can also provide reference for the similar engineering.
The effects of ground deformation pose a significant geo-hazard to the environment and infrastructure in Wuhan, the most populous city in Central China, in the eastern Jianghan Plain at the ...intersection of the Yangtze and Han rivers. Prior to this study, however, rates and patterns of region-wide ground deformation in Wuhan were little known. Here we employ multi-temporal SAR interferometry to detect and characterize spatiotemporal variations of ground deformation in major metropolitan areas in Wuhan. A total of twelve TerraSAR-X images acquired during 2009–2010 are used in the InSAR time series analysis. InSAR-derived results are validated by levelling survey measurements and reveal a distinct subsidence pattern within six zones in major commercial and industrial areas, with a maximum subsidence rate up to −67.3 mm/year. A comparison analysis between subsiding patterns and urban developments as well as geological conditions suggests that land subsidence in Wuhan is mainly attributed to anthropogenic activities, natural compaction of soft soil, and karst dissolution of subsurface carbonate rocks. However, anthropogenic activities related to intensive municipal construction and industrial production have more significant impacts on the measured subsidence than natural factors. Moreover, remarkable signals of secular land uplift are found along both banks of the Yangtze River, especially along the southern bank, with deformation rates ranging mostly from +5 mm/year to +17.5 mm/year. A strong temporal correlation is highlighted between the detected displacement evolutions and the water level records of the Yangtze River, inferring that this previously unknown deformation phenomenon is likely related to seasonal fluctuations in water levels of the Yangtze River.
E.A. Martel (1859-1938) is rightly regarded as one of the most important people in the history of cave study. Writing in French, as he did, his work was little known in those parts of central Europe ...that were in the Austrian empire. Thus much of what he wrote about the Classical Karst was not readily accessible to those now living in that area. It is for that reason that this English translation of his 1894 publication has been made. Martel had been in Slovenia from 14 September 1893 to mid October. He was shown the principal caves and karst features of the region by Wilhelm Putick who had been exploring these places from 1886 onwards. This assistance had been authorised by Count Falkenhayn, the Minister of Agriculture in Wien. Such was the importance with which Martel was regarded internationally.
Karst aquifers are both a valuable resource for humankind and a habitat for unique biota. The quality of freshwater sources may be easily affected by natural (e.g., geology, climate, and vegetation) ...and anthropogenic (e.g., agriculture, livestock, and tourism) changes, particularly in karst landscapes with highly vulnerable groundwater reservoirs. We seasonally monitored nine representative freshwater sources (i.e., six springs, a well, a surface stream, and a cave stream resurgence) in the karst system of the Runcuri Plateau (KSRP) (Western Romanian Carpathians) during seven sampling campaigns in 2019–2021. We assessed how these natural and anthropogenic factors influenced the water quality based on the European and national standards for drinking water. The geological structure (i.e., tectonics and lithology) of the KSRP was reassessed, and the environmental variables of the freshwater sites were investigated in order to evaluate their impact on the physicochemical profile, the microbial contamination, and on the meiofauna presence. Multivariate statistics were performed to gain insights into the interplay among all these factors and to evaluate the self-purification capacity of the KSRP for chemical and microbial pollutants. The most relevant drivers shaping the microbial content of the freshwater sources were the altitude of the sampling sites, the normalized difference vegetation index (NDVI), and air temperature, followed by the physicochemical profile of the waters (i.e., calcium hardness, magnesium hardness, nitrites, nitrates, conductivity, phosphates, total dissolved solids, and iron concentrations). The meiofauna presence was influenced mostly by precipitation, air temperature, and NDVI. Our results reflected the effect of the geological structure and environment on water chemistry and biota assemblages. A pollutant attenuation trend was observed in discharging waters, even though the self-purification capacity of the studied karst system was not statistically supported. More investigations are needed to comprehend the processes developed in the black box of the KSRP.
This is a very dull book. Like a dictionary, it contains only facts: facts that are not readily to be found elsewhere. People who are important in the study of caves and karst are known for what they ...did, what they wrote and whom they influenced. But as individuals they are often no more than a name. They may perhaps be recognized for other aspects, as a King perhaps, or a novelist or a famous doctor. Some, like Darwin or Freud, have changed the world in other ways~but very many had only normal quiet lives during which they also explored, studied or wrote about caves. It is they whose wider lives are difficult to trace and it is 4634 of them who are recorded here, with information from birth certificates, obituaries, unpublished letters and mentions by other people. It is their wider lives that help to show them as real people. In some cases their interest in caves was a part of their professional lives. In many others it provides stimulation and relaxation in otherwise busy lives. But in every case it was the same person and the same brain that enjoyed both~and it was both that made them the people they were. It is only from the biographical sources recorded here, that each person can be understood.
Sustainable development in karst areas should be adapted to its specificities and take into account its vulnerability. The assessment of the development potential and management of karst areas is of ...great importance in Slovenia. This book presents the analyses of the impact of landscape features on the land use and sustainable development in a marginal Slovenian karst landscape ‒ Bela krajina. In order to draw attention to the combination of social perspectives with natural conditions for an integrative view of the karst landscapes, three approaches were used: 1. assessment of the degree of human disturbance to the karst landscape, 2. analyses of land use dynamics, and 3. quantitative and qualitative analyses of the sustainable development of Bela krajina. Karst landscape features affect sustainable development of the study region both positively and negatively. According to local stakeholders the positive effects are mainly connected with tourism, and the negative effects are mainly connected with hampered agriculture. The main message is that karst landscape features should not only be seen as limiting factors, but also for their development potential.
The remediation of buildings with elevated radon concentrations is generally straightforward. However, in some cases a number of attempts may be needed to reduce concentrations to below the reference ...level and, occasionally, it may be impossible to reduce concentrations to below the reference level in a cost effective way. This paper details the work carried out between 2004 and 2012 to reduce radon concentrations in a house with initial radon concentrations of almost 1500 Bq/m
. Over this period, high radon levels were consistently recorded despite the introduction of various radon remedial measures. Remedial work was carried out on ten occasions with 29 radon tests carried out to measure the effect of this work. The paper describes the structure of the house and the karst geology that it is built on and the likely contribution of these factors to the difficulties encountered reducing concentrations. Ultimately, radon concentrations were reduced to about 450 Bq/m
but no further reductions were considered practicable without substantial and costly renovation to the house. Nonetheless, the remedial work carried out to date has resulted in a significant reduction in the risk to the homeowner of developing lung cancer. This work has also added to the understanding of radon remediation techniques in Ireland, particularly for houses built on karst limestone.
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