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Jie Dou - One of the best experts on this subject based on the ideXlab platform.
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Detection of Cover Collapse Doline and Other Epikarst Features by Multiple Geophysical Techniques, Case Study of Tarimba Cave, Brazil
Water, 2020Co-Authors: Yawar Hussain, Rogério Uagoda, Welitom Rodrigues Borges, Renato De Mello Prado, Omar Hamza, Martín Cárdenas-soto, Hans-balder Havenith, Jie DouAbstract:Reliable characterization of the karst system is essential for risk assessment where many associated hazards (e.g., cover-collapse Dolines and groundwater pollution) can affect natural and built environments, threatening public safety. The use of multiple geophysical approaches may offer an improved way to investigate such cover-collapse sinkholes and aid in geohazard risk assessments. In this paper, covered karst, which has two types of shallow caves (vadose and fluvial) located in Tarimba (Goias, Brazil), was investigated using various geophysical methods to evaluate their efficiency in the delineation of the geometry of sediments filled sinkhole. The methods used for the investigation were Electrical Resistivity Tomography (ERT), Seismic Refraction Survey (SRS), Seismic Refraction Tomography (SRT) and the Very Low Frequency Electromagnetic (VLF-EM) method. The study developed several (2D) sections of the measured physical properties, including P-wave velocity and electrical resistivity, as well as the induced current (because of local bodies). For the analysis and processing of the data obtained from these methods, the following approaches were adopted: ERT inversion using a least-square scheme, Karous-Hjelt filter for VLF-EM data and time-distance curves and Vp cross-sections for the SRS. The refraction data analysis showed three-layered stratigraphy topsoil, claystone and carbonate bedrock, respectively. The findings obtained from ERT (three-layered stratigraphy and sediment-filled Doline), as well as VLF-EM (fractured or filled caves as a positive anomaly), were found to be consistent with the actual field conditions. However, the SRS and SRT methods did not show the collapsed material and reached the limited the depth because of shorter profile lengths. The study provides a reasonable basis for the development of an integrated geophysical approach for site characterization of karst systems, particularly the perched tank and collapse Doline.
Derek C. Ford - One of the best experts on this subject based on the ideXlab platform.
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Limestone Dissolution Processes in Beke Doline Aggtelek National Park, Hungary
Earth Surface Processes and Landforms, 1997Co-Authors: L. Zambo, Derek C. FordAbstract:Aggtelek National Park, Hungary, is a limestone karst upland characterized by karren, Dolines and river caves. For a period of two years, climatic and carbonate dissolution variables were monitored at four depths in a 7·5 m shaft through the soil fill in the floor of a typical large (150 m diameter) Doline. Results are compared to other monitoring stations in the shallow soils on side slopes. Runoff and groundwater flow are focused into the base of the Doline soil fill, where moisture is maintained at 70–90 per cent field capacity and temperatures permit year-round production of soil CO2. The capacity to dissolve calcite (limestone) ranges from c. 3 g m−2 per year beneath thin soils on the driest slopes to 17–30 g m−2 per year in the top 1–2 m of Doline fill and at its base 5–7 m below. © 1997 John Wiley & Sons, Ltd.
Marion Iseppi - One of the best experts on this subject based on the ideXlab platform.
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Morphology and distribution of Dolines on ultramafic rocks 1 from airborne 2 LIDAR data- the case of southern Grande Terre in New Caledonia (SW Pacific)
2016Co-Authors: Séverin Pistre, Pierre Genthon, Julie Jeanpert, Jeremy Sérino, Myriam Vendé-leclerc, Jean-luc Folio, Pierre Maurizot, Jean-lambert Join, Marion IseppiAbstract:Dolines are closed geomorphological depressions which are surface manifestations of karstic systems. Usually developed on limestone, they also typify the morphology of the New Caledonian landscape, particularly on the southern massif of the main island (known as Grande Terre). These Dolines are evidence of subsidence, suffosion and collapse phenomena resulting from dissolution weathering of peridotites. However, extensive underground drainage systems are still not yet recognized. Semi-automatic mapping of Dolines is carried out on a 148 kmC area of the Massif du Sud from a high accuracy LIDAR digital elevation model. 8,601 Dolines ranging from 1 mC to 2 kmC are identified and morphologically characterized with precision. The majority of them are small, shallow and round-shaped, yet more complex shapes are locally observed. Size distribution analysis allows the setting of a threshold of 20,000 mC above which surface processes rather than chemical weathering control Doline evolution. Doline density analysis reveals high concentrations on flat areas where ferricrete overlies the complete weathering profile, especially in the case of elevated, rainy watersheds. Dolines are aligned and elongated along a N 135 A 5° major fracture direction, which is inherited from the obduction of the Pacific Plate upper mantle in the Late Eocene. Finally, we propose a pioneering morphometric typology of Dolines that provides important clues as to pseudokarstic activity. We define collapse, bowl-shaped and flat bottom Dolines. Collapse and bowl-shaped Dolines are assumed to denote active pseudokarst. They may widen and deepen, or eventually be filled by sediments. They are distinguished from flat bottom Dolines that are partially to completely filled, which suggests that they are associated with paleo-pseudokarsts. However the groundwater flow paths associated with the genesis and evolution of Dolines must be clarified, and collapse and bowl-shaped Dolines should be hydrologically monitored.
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Morphology and distribution of Dolines on ultramafic rocks from airborne LiDAR data: the case of southern Grande Terre in New Caledonia (SW Pacific)
Earth Surface Processes and Landforms, 2016Co-Authors: Julie Jeanpert, Pierre Genthon, Jeremy Sérino, Myriam Vendé-leclerc, Jean-luc Folio, Pierre Maurizot, Jean-lambert Join, Marion IseppiAbstract:Dolines are closed geomorphological depressions which are surface manifestations of karstic systems. Usually developed on limestones, they also typify the morphology of the New Caledonian landscape, particularly on the southern massif of the main island (known as Massif du Sud). The specificity of Dolines here lies in their development on ultramafic rocks. They are evidences of subsidence, suffosion and collapse phenomena resulting from dissolution weathering of peridotites. However, extensive underground drainage systems are still not yet recognized. Copyright © 2016 John Wiley & Sons, Ltd. Semi-automatic mapping of Dolines is carried out on a 148 km2 area of the Massif du Sud from a high accuracy LiDAR digital elevation model. In this area 8601 Dolines ranging from 1 m2 to 2 km2 are identified and morphologically characterized with precision. Most are small, shallow and round-shaped, yet more complex shapes are locally observed. Size distribution analysis allows the setting of a threshold of 20 000 m2 above which surface processes rather than chemical weathering control Doline evolution. Doline density analysis reveals high concentrations on flat areas where ferricrete overlies the complete weathering profile, especially in the case of elevated rainy watersheds. Dolines are aligned and elongated along a north 135° ± 5° major fracture direction, which is inherited from the obduction of the Pacific Plate upper mantle in the Late Eocene. Copyright © 2016 John Wiley & Sons, Ltd. Finally, we propose a pioneering morphometric typology of Dolines that provides important clues as to pseudokarstic activity. We define collapse, bowl-shaped and flat bottom Dolines. Collapse and bowl-shaped Dolines are assumed to denote active pseudokarst. They may widen and deepen, or eventually be filled by sediments. They are distinguished from flat bottom Dolines that are partially to completely filled, which suggests that they are associated with paleo-pseudokarsts. However the groundwater flow paths associated with the genesis and evolution of Dolines must be clarified, thus collapse and bowl-shaped Dolines should be hydrologically monitored. Copyright © 2016 John Wiley & Sons, Ltd.
María Asunción Soriano - One of the best experts on this subject based on the ideXlab platform.
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detection of underground cavities by combining gravity magnetic and ground penetrating radar surveys a case study from the zaragoza area ne spain
Environmental Earth Sciences, 2008Co-Authors: Tania Mochales, María Asunción Soriano, A M Casas, E L Pueyo, Oscar Pueyo, M T Roman, A Pocovi, Diego AnsonAbstract:A geophysical survey routine is proposed to detect underground cavities and Dolines; it is based on the sequential application of magnetic, low-frequency ground penetrating radar (GPR) and microgravity techniques. A case study near Zaragoza (Ebro valley, Spain) demonstrates the applicability of these methods. The strong contrast of magnetic and electromagnetic properties (and to a lesser scale, of density) between the Doline filling and the surrounding stratified Tertiary and Quaternary rocks allows the shape of filled cavities to be clearly outlined by these methods.
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Alluvial Dolines in the central Ebro basin, Spain: a spatial and developmental hazard analysis
Geomorphology, 1995Co-Authors: María Asunción Soriano, Joséluis SimónAbstract:Abstract Alluvial Dolines are abundant in Quaternary terraces and pediments overlying Neogene gypsum in the Zaragoza area (central Ebro basin). Spatial analysis and experimental simulation show that sulphate content in the groundwater, grain size of the detrital cover, topography of the Tertiary/Quaternary boundary, annual variation of the water table and thickness of the detrital cover are the main factors controlling their development. Taking into account these variables a theoretical spatial hazard model has been elaborated, expressed as a mathematical equation and a hazard map. Both experiments and field data show a high correspondance between two basic mechanisms of evacuation and subsidence (dragging slow subsidence and collapse of cavities) and two basic types of morphology and internal structure of Dolines (basin Doline — funnel structure and well Doline — vault structures, respectively). A genetic classification of Dolines and some evolutionary patterns based on these criteria are developed. Historical changes observed in Doline distribution, as well as field surveys of urban damage and microtopographic profiles allow us to evaluate the present day activity of Dolines. Local subsidence rates measured in urban areas range from 2.5 to 10 cm/year, although Doline generation and reactivation in the whole area tend to be compensated by filling by human activity.
Tamás Telbisz - One of the best experts on this subject based on the ideXlab platform.
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On the size-distribution of solution Dolines in carbonate karst: Lognormal or power model?
Geomorphology, 2020Co-Authors: Eulogio Pardo-igúzquiza, Peter A. Dowd, Tamás TelbiszAbstract:Abstract Dolines, or closed karst depressions, are the most characteristic feature of karst landscapes. The two main types of Doline are those formed by the removal of material by solution and those formed by the geological processes of collapse or suffosion. Solution Dolines are most frequently found in carbonate karst in high relief karst massifs. Various algorithms can be used to identify and delineate Dolines in high-resolution digital elevation models (DEM) where the lower size limit is determined by the resolution of the DEM, i.e., the size of the cell or the DEM pixel in terrain units. The work presented here addresses the size distribution of Dolines, which is a significant component of the geomorphometric analysis of Dolines. On the basis of experimental results, various authors have advocated the lognormal or the power distribution as the best fit to experimental data. A power distribution is consistent with a fractal structure implying the fractal nature of the sizes of Dolines which, in turn, may reflect a relationship between size and the structural controls of fracture networks and the fractal fragmentation of the terrain. This paper presents case studies of four karst landscapes that are representative of karst massifs in Spain. Two of these are located in the Pyrenees in the north of Spain and two are located in the Betic mountains in the south of Spain. In all four cases, a lognormal distribution provides a bad fit while a power law distribution provides a good fit in three cases and in the fourth case provides a good fit for Dolines that have a diameter greater than 50 m.
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the advantage of lidar digital terrain models in Doline morphometry compared to topographic map based datasets aggtelek karst hungary as an example
Acta Carsologica, 2016Co-Authors: Tamás Telbisz, Tamás Látos, Márton Deák, Balázs Székely, Zsófia Koma, Tibor StandovárAbstract:Doline morphometry has always been in the focus of karst geomorphological research. Recently, digital terrain model (DTM) based methods became widespread in the study of Dolines. Today, LiDAR datasets provide high resolution DTMs, and automated Doline recognition algorithms have been developed. In this paper, we test different datasets and a Doline recognition algorithm using Aggtelek Karst (NE-Hungary) Dolines as a case example. Three datasets are compared: “TOPO” Dolines delineated by the classical outermost closed contour method using 1:10,000 scale topographic maps, “KRIG” Dolines derived automatically from the DTM created by kriging interpolation from the digitized contours of the same topographic maps, and finally “LiDAR” Dolines derived automatically from a DTM created from LiDAR data. First, we analyzed the sensitivity of the automatic method to the “depth limit” parameter, which is the threshold, below which closed depressions are considered as “errors” and are filled. In the actual case, given the typical Doline size of the area and the resolution of the DTMs, we found that ca. 0.5 m is the optimal depth limit for the LiDAR dataset and 1 m for the KRIG dataset. The statistical distributions of the morphometrical properties were similar for all datasets (lognormal distribution for area and gamma distribution for depth), but the DTM-based methodology resulted larger Dolines with respect to the classical method. The planform area (and related characteristics) showed very high correlations between the datasets. Depth values were less correlated and the lowest (moderately strong) correlations were observed between circularity values of the different datasets. Slope histograms calculated from the LiDAR data were used to cluster Dolines, and these clusters differentiated Dolines similarly to the classical depth-diameter ratio. Finally, we conclude that in the actual case, Dolines can be morphometrically well characterized even by the classical topographic method, though finer results can be achieved for the depth and shape related parameters by using LiDAR data. Key words: Doline morphometry, LiDAR, interpolation, slope histogram, sink point. Prednost lidarskega digitalnega modela reliefa za raziskavo morfometrije vrtac v primerjavi s podatkovno bazo topografskih kart − primer Agteleskega krasa (Madžarska) Morfometrija vrtac je bila vedno v srediscu kraskih geomorfoloskih raziskav. V zadnjem casu so pri raziskavah vrtac postale zelo razsirjene metode, ki temeljijo na digitalnem modelu reliefa (DMR). Lidarski podatki zagotavljajo visoko locljivostne DMR-je, razviti so bili avtomatski algoritmi za prepoznavanje vrtac. V tem prispevku smo na primeru Agteleskega krasa v severovzhodni Madžarski preizkusili razlicne podatkovne baze in algoritme za prepoznavanje vrtac. Primerjali smo tri podatkovne baze: "TOPO" vrtace so razmejene na klasicen nacin z zunanjo zaprto plastnico na topografski karti v merilu 1: 10.000, "KRIG" vrtace so v istem merilu s pomocjo kriginga samodejno pridobljene iz digitaliziranih plastnic DMR, in "LiDAR" vrtace so samodejno pridobljene iz DMR, ki je ustvarjen iz lidarskih podatkov. Najprej smo analizirali obcutljivost avtomatske metode parametra "mejne globine", ki predstavlja prag, pod katerim se depresijske oblike stejejo kot "napake" in so zapolnjene. V konkretnem primeru smo glede na obicajno velikost vrtace in locljivosti DMR ugotovili, da je optimalna globinska meja za LiDAR ca. 0,5 m in 1 m za KRIG. Pri vseh podatkovnih bazah so bile statisticne porazdelitve morfometrijskih lastnosti (logaritemska normalna porazdelitev za prostor in gama porazdelitev za globino) podobne, vendar metodologija, ki temelji na DMR privede do rezultatov, ki kažejo na vecje vrtace v primerjavi s klasicno metodo. Rezultati obmocij vrtac (in njihovih znacilnosti) so pokazali zelo visoke korelacije med podatkovnimi nizi. Pri globinah so bile korelacije manjse in najnižje zabeležene korelacije (srednje mocne) so bile med podatki razlicnih podatkovnih bazah. Histogrami naklona, izracunani iz lidarskih podatkov, so bili uporabljeni za združevanje vrtac, in ti grozdi razlikujejo vrtace glede na klasicno razmerje med globino in premerom. Na koncu smo ugotovili, da lahko v konkretnem primeru dobro dolocimo morfometricne lastnosti vrtac s klasicnimi topografskimi metodami. Podrobnejse rezultate o globinah in oblikah lahko dosežemo na podlagi lidarskih podatkov. Kljucne besede: morfometrija vrtac, LiDAR, interpolacija, histogram naklona, ponor.
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The advantage of lidar digital terrain models in Doline morphometry compared to topographic map based datasets – Aggtelek karst (Hungary) as an example
Acta Carsologica, 2016Co-Authors: Tamás Telbisz, Tamás Látos, Márton Deák, Balázs Székely, Zsófia Koma, Tibor StandovárAbstract:Doline morphometry has always been in the focus of karst geomorphological research. Recently, digital terrain model (DTM) based methods became widespread in the study of Dolines. Today, LiDAR datasets provide high resolution DTMs, and automated Doline recognition algorithms have been developed. In this paper, we test different datasets and a Doline recognition algorithm using Aggtelek Karst (NE-Hungary) Dolines as a case example. Three datasets are compared: “TOPO” Dolines delineated by the classical outermost closed contour method using 1:10,000 scale topographic maps, “KRIG” Dolines derived automatically from the DTM created by kriging interpolation from the digitized contours of the same topographic maps, and finally “LiDAR” Dolines derived automatically from a DTM created from LiDAR data. First, we analyzed the sensitivity of the automatic method to the “depth limit” parameter, which is the threshold, below which closed depressions are considered as “errors” and are filled. In the actual case, given the typical Doline size of the area and the resolution of the DTMs, we found that ca. 0.5 m is the optimal depth limit for the LiDAR dataset and 1 m for the KRIG dataset. The statistical distributions of the morphometrical properties were similar for all datasets (lognormal distribution for area and gamma distribution for depth), but the DTM-based methodology resulted larger Dolines with respect to the classical method. The planform area (and related characteristics) showed very high correlations between the datasets. Depth values were less correlated and the lowest (moderately strong) correlations were observed between circularity values of the different datasets. Slope histograms calculated from the LiDAR data were used to cluster Dolines, and these clusters differentiated Dolines similarly to the classical depth-diameter ratio. Finally, we conclude that in the actual case, Dolines can be morphometrically well characterized even by the classical topographic method, though finer results can be achieved for the depth and shape related parameters by using LiDAR data. Key words: Doline morphometry, LiDAR, interpolation, slope histogram, sink point. Prednost lidarskega digitalnega modela reliefa za raziskavo morfometrije vrtac v primerjavi s podatkovno bazo topografskih kart − primer Agteleskega krasa (Madžarska) Morfometrija vrtac je bila vedno v srediscu kraskih geomorfoloskih raziskav. V zadnjem casu so pri raziskavah vrtac postale zelo razsirjene metode, ki temeljijo na digitalnem modelu reliefa (DMR). Lidarski podatki zagotavljajo visoko locljivostne DMR-je, razviti so bili avtomatski algoritmi za prepoznavanje vrtac. V tem prispevku smo na primeru Agteleskega krasa v severovzhodni Madžarski preizkusili razlicne podatkovne baze in algoritme za prepoznavanje vrtac. Primerjali smo tri podatkovne baze: "TOPO" vrtace so razmejene na klasicen nacin z zunanjo zaprto plastnico na topografski karti v merilu 1: 10.000, "KRIG" vrtace so v istem merilu s pomocjo kriginga samodejno pridobljene iz digitaliziranih plastnic DMR, in "LiDAR" vrtace so samodejno pridobljene iz DMR, ki je ustvarjen iz lidarskih podatkov. Najprej smo analizirali obcutljivost avtomatske metode parametra "mejne globine", ki predstavlja prag, pod katerim se depresijske oblike stejejo kot "napake" in so zapolnjene. V konkretnem primeru smo glede na obicajno velikost vrtace in locljivosti DMR ugotovili, da je optimalna globinska meja za LiDAR ca. 0,5 m in 1 m za KRIG. Pri vseh podatkovnih bazah so bile statisticne porazdelitve morfometrijskih lastnosti (logaritemska normalna porazdelitev za prostor in gama porazdelitev za globino) podobne, vendar metodologija, ki temelji na DMR privede do rezultatov, ki kažejo na vecje vrtace v primerjavi s klasicno metodo. Rezultati obmocij vrtac (in njihovih znacilnosti) so pokazali zelo visoke korelacije med podatkovnimi nizi. Pri globinah so bile korelacije manjse in najnižje zabeležene korelacije (srednje mocne) so bile med podatki razlicnih podatkovnih bazah. Histogrami naklona, izracunani iz lidarskih podatkov, so bili uporabljeni za združevanje vrtac, in ti grozdi razlikujejo vrtace glede na klasicno razmerje med globino in premerom. Na koncu smo ugotovili, da lahko v konkretnem primeru dobro dolocimo morfometricne lastnosti vrtac s klasicnimi topografskimi metodami. Podrobnejse rezultate o globinah in oblikah lahko dosežemo na podlagi lidarskih podatkov. Kljucne besede: morfometrija vrtac, LiDAR, interpolacija, histogram naklona, ponor.
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Doline morphometric analysis and karst morphology of Biokovo Mt (Croatia) based on field observations and digital terrain analysis.
Hrvatski geografski glasnik Croatian Geographical Bulletin, 2009Co-Authors: Tamás Telbisz, Hrvoje Dragušica, Balász NagyAbstract:Biokovo Mt is part of the Outer Dinarides, in a coastal position with a NW-SE main tectonic orientation. The highest peak called Sveti [Sv.] Jure (1762 m) towers above a karst plateau of 1300-1400 m mean elevation. Both of the long margins of Biokovo are characterized by steep and high relief energy rockwalls formed along tectonic fault lines. The plateau is intensely karstified with diverse karren forms, large Dolines and several shaft caves. Its unique karstmorphological features are the relatively deep Dolines with steep walls, so the landscape is characterized mainly by the sharp interDoline ridges and pyramidal peaks instead of negative Doline forms. Based on the previous observation, the Biokovo plateau can be considered a "polygonal karst". The geomorphological map of a study area from this plateau has been elaborated, based on field observations and topographical maps. After digitizing the contour lines, we have created the digital elevation model (DEM) of the study area and carried out sophisticated Doline-morphometrical analysis using the DEM. The most important and unique feature of the landscape, the polygonal structure, has been derived from the DEM using GIS hydrologic modelling tools.
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Doline morphometry of mt. Miroč using GIS methods
Glasnik Srpskog geografskog drustva, 2007Co-Authors: Tamás Telbisz, László Mari, Jelena CalicAbstract:Mt. Miroc Doline karst evolution and its determining factors such as geology, relief and structure are analyzed using GIS tools. The 3064 Dolines found in a 123 km2 area support the use of different statistical methods. Doline density (24.9 km-2) is relatively high and mean Doline area (1697 m2) is relatively small. Both frequency analysis and field evidence suggest that Doline karst evolution of the area is at a relatively young stage. Spatial distribution of the Dolines is mainly determined by the Upper Jurassic limestone, and slope angle less than 12°. Furthermore, the anticline limbs and axis as well as the SW-NE trend fault lines are also in connection with Doline density. However, Doline long axis orientation is tpyically NW-SE, which is not in accordance with the observed rupture systems. Therefore, this issue requires further research.