Karst

El r io Gallego es un afluente principal del Ebro por su orilla izquierda, en el nordeste de Espana. Fluye a traves de 192 kilometros, desde la frontera francesa hasta la ciudad de Zaragoza. En Sabinanigo, desde 1975 a 1989, la empresa Inquinosa (Industrias Quimicas del Noroeste) produjo el insecticida lindano (γ-hexaclorocicloxano [HCH]), generando aproximadamente 115 000 toneladas de residuos toxicos que se acumularon basicamente en dos vertederos, Bailin y Sardas, ambos situados cerca de la fabrica y del rio, ademas de en un numero desconocido de vertederos menores. Durante el verano de 2014, los residuos de γ-HCH del vertedero de Bailin fueron transferidos a un cercano y nuevo vertedero de mas seguridad. Desafortunadamente, una masa desconocida de γ-HCH se vertio al barranco de Bailin, produciendo la consecuente contaminacion del rio Gallego por efecto de fuertes lluvias. Se prohibio el uso del suministro publico de agua en varias poblaciones y tambi en se vieron afectadas las a...

espanolLos manantiales karsticos son los puntos de salida del agua que circula y esta almacenada en los acuiferos karsticos. La descarga de estos manantiales puede variar muchisimo, desde pequenos rezumes a caudales de varias decenas de metros cubicos por segundo, capaces de originar rios. A lo largo de la historia, los manantiales karsticos han sido determinantes a la hora de establecer asentamientos humanos y son numerosos los pueblos y ciudades que se abastecen de sus aguas, generalmente de excelente calidad. El comportamiento de los acuiferos karsticos difiere en gran medida de otros tipos de acuiferos y sus manantiales presentan ciertas singularidades. El presente trabajo pretende mostrar algunos de estos aspectos a partir de ejemplos de varios manantiales de la geografia espanola. EnglishKarst springs are the outlets of the water that flows and is stored in karstic aquifers. The discharge of these springs can vary greatly, from small leakages virtually unnoticed to flow rates ...

Quarrying of carbonate rocks for various purposes dates back to early times. The impact of quarries on the environment and particularly on the groundwater system in terms of quality and quantity has often been ignored until the last few decades. Regardless of the small amount of quarried rock compared to the volume of an outcrop, the result of removing the protective cover of an aquifer may cause severe pollution of the groundwater. Another impact is that groundwater flow patterns may change due to manmade effects, such as blasting. Sites of quarries, therefore, should be selected by considering the hydrogeological, environmental and economic factors.

The paper provides genetic classification of lakes in the Czech Republic. We separate lakes to two groups - natural and anthropogenic origin. The genetic classification is based on the classification of lakes according to the way of origination of the lake basin while the geomorphologic viewpoint prevails: glacial lakes, fluvial lakes, karst lakes, lakes dammed-up by landslides, organogenous lakes and anthropogenic lakes. As the anthropogenic lakes we may regard all the water bodies which originated as a consequence of the human activity - mining of mineral resources.

Establishing a chronology of events is a critical step in reconstructing the palaeoclimate and it is important for all types of environmental records, including speleothems. Here, we analysed a unique series of flowstones deposited between 3.2 Ma (marine isotope stage (MIS) Km3) and 0.08 Ma (MIS 5). The studied flowstones are located in a classic karstic environment, the Račiška Pečina Cave in south-western Slovenia. Further, a detailed chronology of events was constructed based on oxygen isotope stratigraphy (OIS), combined with magnetostratigraphy and U-series dating. Two curves were selected as reference records where the LR04 record was used as the global curve and a Mediterranean record was used as the regional curve. The Račiška Pečina profile was divided into two segments separated by a principal disconformity. The lower segment correlated better with the regional Mediterranean curve, while the upper segment was with the global LR04 curve. These findings suggest that the main...

The aim of this study was the assessment of groundwater vulnerability and pollution risk of the Perivleptos karst aquifer in the northwestern part of Greece. Hence, the EPIK method has been applied within the study area. Additionally, a detailed literature overview has been obtained, including the worldwide application of the EPIK method. The hazard map has been developed for the implementation of risk assessment. The resulting vulnerability map was divided into four classes and showed especially high to very high vulnerability. The subsequent hazard assessment has shown mostly low to moderate endangerment for the northern part of the study area, which is mainly covered by forest, while the areas covered by urban and industrial, as well as agricultural land, use primarily show high to very high endangerment. Concluding in the risk map, the study area consists of 13% of very high, 48% of high, 36% of moderate and 4% of low risk of contamination. According to the literature overview, ...

This paper describes the design and construction of a multi-material grout curtain to cut off a major inflow through karstic features from a river to a nearby limestone quarry. A total of over 16,700 yd (12,800 m) of slurry, Low Mobility Grouts, and hot bitumen were injected to depths of over 200 feet (60 m) along a 1500-foot (460-m) long curtain in several phases. The value of real time monitoring of all relevant hydrogeological as well as grouting parameters during the execution of such works is clearly demonstrated. This is believed to be the largest project of its type undertaken to date in North America.

The AguelmamAzegza lake is located in the Middle Atlas mountain range, this region consists of carbonate rocks of Lias. It is the best-watered and richest region in Morocco in terms of wetlands, especially natural lakes, rivers and fresh springs. The lake’s water supply is ensured by the inflows of water in the form of underwater sources fed by precipitation (rain and snow) following tectonics and the genesis of karstic formations by the dissolution of carbonate rocks. The declining trend in lake levels in recent years results from the decrease in precipitation which decreases during these years.

Buried karst features result from a complex interplay between carbonate bedrock and structural geology. The enhancement of carbonate aquifers through this interplay creates hydrogeologically complex subsurface drainage networks and highly variable surface topographies. This article reports on the sediment fill and fossil pollen record from a large enclosed negative karst landform at Coolough, near Galway City in the west of Ireland. The landform was discovered during the preliminary site investigation for the proposed N6 Galway City Ring Road. Major joint sets developed in the Carboniferous (Mississippian) Limestone bedrock govern the local hydrogeology and structural evidence suggests that a local fault has controlled the east–west propagation of the deep enclosed depression. Fluvial and lacustrine palaeoenvironments are interpreted from the sediments infilling the enclosed depression, within which three discrete diamicts are identified, potentially representing distinct phases of ...

In the framework of the largest urban-transit system ever built from scratch, the Riyadh Metro Project (6 lines totaling 176 km), a comprehensive investigation was carried out for karst detection, prevention and correction. This case study of the Metro Line 3 (41.6 km) seeks to show how the multi-technique geophysical survey (seismic refraction, electrical resistivity and ground penetration radar down to 40–50 m depth) was found to be a successful tool in detecting karst features. Preventive measures included systematic probing drilling to anticipate karst cavities below foundations (653 piers) and tunnel lining evaluation using 2D finite elements. Finally, this paper provides initial guidance of the corrective techniques used for each engineering challenge, such as cavity filling with grouting, geogrid reinforcement, etc.

68 Coronado National Memorial is one of the most southern National Park units in the United States and the largest of the 29 Memorials (Figure 1). The Memorial is located in the southern portion of the Huachuca Mountains in the Mexican Highland section of the Basin and Range Province. The Huachucas are one of 40 mountain ranges in the borderlands named “sky islands.” These mountain ranges received the name because they resemble islands that rise above the grassy sea. There are seven located caves within the Memorial and possibly three other unlocated caves. Only three are of subCave Management and Restoration Efforts at Coronado National Memorial, Hereford, AZ

A new epilithic Sellaphora (Bacillariophyceae) species from a karst spring of Sardinia is described based on light and scanning electron microscopic observations. Sellaphora gologonica sp. nov. shares similarities with small-celled Sellaphora previously described from Europe and particularly with S. atomoides, S. hafnearae and S. seminulum. Sellaphora gologonica seems to be related to S. seminulum based on the striae patterns and valve ultrastructure, as well as the sinuous raphe system. The main differences between S. gologonica and S. seminulum lies in its valve shape (small, elliptic to oval), not presenting capitated nor protracted apices, as in the later taxon. Sellaphora gologonica was discovered in freshwater habitats with slightly alkaline and oligotrophic waters presenting medium hardness and mineralization, at the smaller water emergence of karst spring system Su Gologone (Sardinia).

The upper carbonate member of the Kaibab Formation in northern Arizona (USA) was subaerially exposed during the end Permian and contains fractured and zoned chert rubble lag deposits typical of karst topography. The karst chert rubble has secondary (authigenic) silica precipitates suitable for estimating continental weathering temperatures during the end Permian karst event. New oxygen and hydrogen isotope ratios of secondary silica precipitates in the residual rubble breccia: (1) yield continental palaeotemperature estimates between 17 and 22 °C; and, (2) indicate that meteoric water played a role in the crystallization history of the secondary silica. The continental palaeotemperatures presented herein are broadly consistent with a global mean temperature estimate of 18.2 °C for the latest Permian derived from published climate system models. Few data sets are presently available that allow even approximate quantitative estimates of regional continental palaeotemperatures. These d...

Figure 1 – Entrance of Salitre cave, in quartzite rock. Site of numerous opportunities for public use and environmental interpretation. Figure 2 – Entrance of Capela Velha cave with a rock cross on the floor. Photo: Luciana Alt and Vitor Moura. Introduction and objectives Caves are fragile, complex and low resilience environments however caves provide unique scientific, educational and recreational opportunities for visitors. These uses, without proper management, can severely impact or even destroy the attributes that provide such opportunities. Many of these resources are not renewable, and in these cases the damage is irreversible. There are some caves with established public use, still incipient in the southern portion of the Espinhaco Mountain Range. Among the main observed uses, we highlight the sporadic visitation of rare beauty speleological sites (Figure 1), the religious use (Figure 2) and the practice of adventure sports (climbing, rappelling and others). None of the iden...

Groundwater is a major resource for drinking water, especially in developing countries, where it is less expensive to treat than surface water. Today, the resource is highly susceptible to pollution, particularly as a result of human activity. This review was based on a literature review and critical analysis of models for estimating the groundwater vulnerability. The results show that the deepest porous aquifers are the least susceptible to pollution, whereas those in karstic and fissured environments are susceptible, whatever their depth. Pollution usually arises from human activity. Critical analysis of the literature shows that existing methods are developed in specific environmental contexts. Given the variability of factors in space and time, these methods do not take the intrinsic realities of all natural settings into account adequately and are not perfectly applicable in all environments. This highlights the need to develop appropriate models for each environment, such as t...

O hidrogeólogo e geomorfólogo Alexander Klimchouk (1956-2023) dedicou grande parte da sua vida profissional ao estudo da espeleogénese hipogénica, ou seja, de uma tipologia muito específica de atuação dos processos de carsificação em profundidade, ligada a uma recarga hídrica per ascensum. É aqui proposto um modelo cartográfico preliminar que evidencia os principais setores da Orla-Meso-Cenozoica Ocidental de Portugal potencialmente capazes de manifestar indícios de espeleogénese hipogénica.