Esquemas de recesión de la descarga de los manantiales kársticos observados en los acuíferos de carbonatos del Triásico de Eslovaquia

Abstract

Master recession curves of 117 karstic springs from Middle and Upper Triassic carbonate aquifers in the Slovakian territory of the mountainous Western Carpathians were assembled from gauged discharge data. Identified slow-flow and fast-flow components were very diversely represented. Fast-flow components were missing in 47% of springs. In another 20% of springs, only fast-flow components were recognized, while slow-flow components were absent. Simultaneous discharge of both slow-flow and fast-flow components was found at 39 springs (33%). Known geology of recharge areas enabled examination of the impact that outcropping dolomites and/or limestones may pose to the discharge recession. It was found that dolomites in springsheds significantly affect slow-flow components, but do not influence the occurrence of the fast-flow ones. The purely fast-flow-driven recession was present both in limestone and dolomitic springsheds, but merely one fast-flow component was typical for the dolomitic ones. Two or three fast-flow components may appear in "purely limestone" springsheds. Recession coefficients of slow-flow components were within the interval of 0.0004-0.18 days −1 and those of fast-flow within 0.0017-0.31 days −1 . The duration of the fast-flow components is mostly several days or several tens of days, while the theoretical duration of slow-flow may last for decades. Storage in matrix, fractures or conduits of the saturated zone cannot be separately estimated because, in discharged volumes, water from unsaturated and epikarst zones is included. Variable shapes of assembled master recession curves point to the important influence of unsaturated and epikarst zones on the discharge recessional patterns of karst springs.

Structural Classification, Discharge Statistics, and Recession Analysis from the Springs of the Gran Sasso (Italy) Carbonate Aquifer; Comparison with Selected Analogues Worldwide

“…Overall, this spring (MT), located along a normal fault, is characterized by SVCP, V, and I v two to five times lower when compared with either the springs in heavy folds in the proximity of a thrust (VA, and VB; Group 1) or springs (VO, MA, and CH; Group 2) with the emergence of water related to the thrust (Tables 1-3). This scenario depicts the control the structural geology has on the hydrological statistics that were not found by all the recent statistical studies on spring discharges, e.g., [7,10,12,26,40,41,63]. The structural style is not the only factor that plays a role in the computed statistics.…”

“…The relative importance of conduits and fractures in driving the groundwater flow affects the discharge rates at spring outlets and, therefore, the availability of natural water resources during the hydrological year in karst environments. Applying robust statistics to the hydrographs of the discharge and studying the recession provide information on the reliability, degree of variability, and also the flow regime within the saturated part of the fractured and karst aquifers [7][8][9][10][11][12]. Due to the economic and civil importance of the karst water resources, a statistical study of the discharge regime started back in the 1920s with the introduction of the first statistical parameters [13].…”

Identification of karst spring hydrographs using laboratory and numerical simulations considering combined discrete‐continuum approaches

“…Figure 5 displays the decomposition process of spring recession limbs using the improved exponential function. It was hypothesized that all recession components take effect at the beginning of the recession limb, and only the slow recession exists throughout the process (Fu et al, 2016; Malík et al, 2021). Therefore, the linear function corresponding to the slow recession component $$$ \left({a}_1t+{b}_1\right) $$$ was initially derived using data from the tail stage following the logarithmic transformation (Figure 5a,b).…”

“…Fu et al (2016) performed a quantitative analysis of spring hydrographs by three recession models and deduced the hydraulic properties of fractures and conduits. Spring recession analysis has a long history in hydrology and has been regarded as a useful tool for identifying karst aquifer characteristics, while the decomposition of recession components and the determination of parameters involved are relatively complex (Fiorillo, 2014; Malík et al, 2021).…”