Community news

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That exokarst is all features that may be found on a surface karst landscape, ranging in size between tiny karren forms and extensive projes, belong to the exokarst [9]. see also endokarst.?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

What is Karstbase?



Browse Speleogenesis Issues:

KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
See all featured articles from other geoscience journals

Search in KarstBase

Your search for yucatan (Keyword) returned 37 results for the whole karstbase:
Showing 16 to 30 of 37
Conduit hydrogeology of a tropical coastal carbonate aquifer. MSc thesis, 1999, Beddows, P. A

The aim of this study is to investigate the hydrogeology of the submerged conduit systems of a coastal carbonate aquifer (Caribbean coast, Yucatan Peninsula, Mexico), and thereby better understand their significance as large permeability heterogeneities. A complex spatial trend in conduit flow rates (determined by quantitative fluorescent dye tracing initiated 6 km inland) was found, including significant velocity variation between consecutive conduit segments. Elevated coastal velocities under low tide conditions are shown by salinity profiling, to be induced by the volumetric increase of discharging water from mixing with marine water. Semi-diurnal micro-tidal loading is sufficient to induce flooding from the sea into the conduits at one coastal discharge point, and significantly reduce flow rates at another. Furthermore, a network of four observation sites extending 5 km inland indicates efficient propagation of the ~0.30 m tidal signal through the Nohoch Nah Chich conduit system, a distance several time greater than previously appreciated in this environment. The field results clearly indicate that the hydrogeological flux is dominated by cavernous porosity, and that the aquifer is dynamically responsive to the high-frequency low-magnitude tidal loading to a significant distance inland. Conventional coastal groundwater models such as the Ghyben-Herzberg lens model, assume isotropic homogeneous equivalent-porous-medium conditions. Because the corollaries of the conventional models are inconsistent with the field evidence, they are inapplicable in this environment. It is hoped that these results will aid future modelling efforts, and improve our capacity to manage the valuable groundwater resources which represents the unique source of potable water to the local population.

Last interglacial reef growth beneath Belize barrier and isolated platform reefs, 2000, Gischler Eberhard, Lomando Anthony J. , Hudson J. Harold, Holmes Charles W. ,
We report the first radiometric dates (thermal-ionization mass spectrometry) from late Pleistocene reef deposits from offshore Belize, the location of the largest modern reef complex in the Atlantic Ocean. The results presented here can be used to explain significant differences in bathymetry, sedimentary facies, and reef development of this major reef area, and the results are significant because they contribute to the knowledge of the regional geology of the eastern Yucatan. The previously held concept of a neotectonically stable eastern Yucatan is challenged. The dates indicate that Pleistocene reefs and shallow-water limestones, which form the basement of modern reefs in the area, accumulated ca. 125-130 ka. Significant differences in elevation of the samples relative to present sea level (>10 m) have several possible causes. Differential subsidence along a series of continental margin fault blocks in combination with variation in karstification are probably the prime causes. Differential subsidence is presumably related to initial extension and later left-lateral movements along the adjacent active boundary between the North American and Caribbean plates. Increasing dissolution toward the south during Pleistocene sea-level lowstands is probably a consequence of higher precipitation rates in mountainous southern Belize

Symposium Abstract: Hydrodynamics of the density stratified carbonate aquifer of the Yucatan peninsular, Mexico, 2001, Beddows P. A. , Smart P. L. , Whitaker F. F. , Smith S. L.

Spaceborne imaging radar-C (SIR-C) observations of groundwater discharge and wetlands associated with the Chicxulub impact crater, northwestern Yucatan Peninsula, Mexico, 2001, Pope Kevin O. , Rejmankova Eliska, Paris Jack F. ,
Analyses of spaceborne imaging radar-C (SIR-C) data and field data from the northwestern Yucatan Peninsula, Mexico, demonstrate that spaceborne multifrequency polarimetric radars are excellent tools for characterizing patterns of wetland flooding. Seasonal flooding can be detected in most types of forest and marsh in the radar backscatter magnitude and phase data of both L and C band. Field observations made in the wet and dry seasons concurrent with the space missions and chemical analyses of floodwaters confirm that flooding is the product of discharge from the Yucatan aquifer, which consists of a fresh-water lens floating on seawater. This discharge controls the distribution of wetlands. Therefore, vegetation and flooding patterns, mapped with SIR-C imagery, provide valuable information on the hydrogeology of the region. Radar-image maps of wetlands and flooding indicate that there are three major zones of groundwater discharge that correlate with structures of the buried Chicxulub crater--zone 1 with the peak ring, zone 2 with the crater rim, and zone 3 with the exterior ring. Zone 1 has sulfate-poor discharge, unlike the sulfate-rich discharge in zones 2 and 3. The highest discharge is in zone 3, where the buried crater is closest to the surface. This groundwater-discharge pattern can be explained by tidal pumping of fresh water to the surface through high permeability zones developed in the Tertiary carbonates overlying crater faults and escarpments

Designation of protected karstlands in Central America: A regional assessment, 2002, Kueny, J. A. , Day, M. J.
The IUCN World Commission on Protected Areas has recognized karst landscapes as important targets for designation as protected areas, and this study is a regional inventory of the Central American karst conservation situation. Central America is a significant international carbonate karst landscape, covering ~154,000 km2, roughly a quarter of the regional land area. The karstlands exhibit considerable topographic diversity, including cockpit and tower styles, together with extensive dry valleys, cave systems and springs. Some of the karst areas are well known, but others have yet to receive detailed scientific attention. Many of them have archaeological, historical, cultural, biological, aesthetic and recreational significance, but human impacts have been considerable. Conservation and protection legislation is variable in nature and effectiveness, and enforcement is problematic. About 18% of the Central American karst landscape has been afforded nominal protection through designation as protected areas. Regional levels of karstland protection are highly variable, with significant protection in the Yucatan peninsula, Honduras, and Belize; intermediate protection in Guatemala, Costa Rica, and Panama; and, as yet, no protected areas in Nicaragua or El Salvador. The situation remains fluid and the future of the Central American karstlands uncertain.

Groundwater-flow modeling in the Yucatan karstic aquifer, Mexico, 2002, Gonzalezherrera R. , Pinto I. , Gamboavargas J. ,
The current conceptual model of the unconfined karstic aquifer in the Yucatan Peninsula, Mexico, is that a fresh-water lens floats above denser saline water that penetrates more than 40 km inland. The transmissivity of the aquifer is very high so the hydraulic gradient is very low, ranging from 7-10 mm/km through most of the northern part of the peninsula. The computer modeling program AQUIFER was used to investigate the regional groundwater flow in the aquifer. The karstified zone was modeled using the assumption that it acts hydraulically similar to a granular, porous medium. As part of the calibration, the following hypotheses were tested: (1) karstic features play an important role in the groundwater-flow system; (2) a ring or belt of sinkholes in the area is a manifestation of a zone of high transmissivity that facilitates the channeling of groundwater toward the Gulf of Mexico; and (3) the geologic features in the southern part of Yucatan influence the groundwater-flow system. The model shows that the Sierrita de Ticul fault, in the southwestern part of the study area, acts as a flow barrier and head values decline toward the northeast. The modeling also shows that the regional flow-system dynamics have not been altered despite the large number of pumping wells because the volume of water pumped is small compared with the volume of recharge, and the well-developed karst system of the region has a very high hydraulic conductivity

The hydrogeochemistry of the karst aquifer system of the northern Yucatan Peninsula, Mexico, 2002, Perry E. , Velazquezoliman G. , Marin L. ,
Based on groundwater geochemistry, stratigraphy, and surficial and tectonic characteristics, the northern Yucatan Peninsula, Mexico, a possible analog for ancient carbonate platforms, is divided into six hydrogeochemical/physiographic regions: (1) Chicxulub Sedimentary Basin, a Tertiary basin within the Chicxulub impact crater; (2) Cenote Ring, a semicircular region of sinkholes; (3) Pockmarked Terrain, a region of mature karst; (4) Ticul fault zone; (5) Holbox Fracture Zone-Xel-Ha Zone; and (6) Evaporite Region. Regional characteristics result from tectonics, rock type, and patterns of sedimentation, erosion, and rainfall. The Cenote Ring, characterized by high groundwater flow, outlines the Chicxulub Basin. Most groundwater approaches saturation in calcite and dolomite but is undersaturated in gypsum. Important groundwater parameters are: SO4/Cl ratios related to seawater mixing and sulfate dissolution; Sr correlation with SO4, and saturation of Lake Chichancanab water with celestite. indicating celestite as a major source of Sr; high Sr in deep water of cenotes, indicating deep circulation and contact of groundwater with evaporite; and correlation of Ca, Mg, and SO4, probably related to gypsum dissolution and dedolomitization. Based on geochemistry we propose: (1) a fault between Lake Chichancanab and Cenote Azul; (2) deep seaward movement of groundwater near Cenote Azul; and (3) contribution of evaporite dissolution to karst development in the Pockmarked Terrain. Chemical erosion by mixing-zone dissolution is important in formation of Estuario Celestun and other estuaries, but is perhaps inhibited at Lake Bacalar where groundwater dissolves gypsum, is high in Ca, low in CO3, and does not become undersaturated in calcite when mixed with seawater

Development of a Protection Strategy of Karst Limestone Aquifers: The Merida Yucatan, Mexico Case Study, 2002, Escolero Oa, Marin Le, Steinich B, Pacheco Aj, Cabrera Sa, Alcocer J,

Density stratified groundwater circulation on the Caribbean coast of the Yucatan Peninsula, Mexico, 2002, Beddows P. A. , Smart P. L. , Whitaker F. F. , Smith S. L.

Symposium Abstract: Decoupled density stratified groundwater circulation on the Caribbean coast of the Yucatan Peninsula, Mexico, 2003, Beddows P. A. , Smart P. L. , Whitaker F. F. , Smith S. L.

Symposium Abstract: Active dolomitisation by saline groundwaters in the Yucatan Peninsula, Mexico, 2003, Smith S. L. , Whitaker F. F, Parkes J. R, Smart P. L, Beddows P. A. , Bottrell S. H.

Yucatan Phreas, Mexico, 2004, Beddows P. A.

Groundwater Hydrology of a Coastal Conduit Carbonate Aquifer: Caribbean Coast of the Yucatán Peninsula, México, PhD Thesis, 2004, Beddows, Patricia A.

Over 500 km of horizontally extensive submerged cave passages have been explored within the density-stratified carbonate aquifer of the Caribbean coast of the Yucatan Peninsula. These drain the large inland recharge area to the coastal margin and represent important regional-scale anisotropic permeability features. However, conventional theory is inadequate to explain this aquifer where conduit flows dominate within a high permeability matrix. Cave diving and surface observations have been used to develop a regional and multi-seasonal dataset of the density-stratified water column, and the circulation within the fresh and saline waters. A sharp mixing zone (MZ; 0.3 - 4 m thick) separates a cool fresh water lens (FWL) from a warmer saline water zone (SWZ) within the conduits. The SWZ temperature is highest at the coast (~ 28.0 oC) and decreases to ~ 25.5 oC at 10 km inland, while the FWL temperature is spatially constant (25 ± 0.2 oC, n = 33). The MZ has subtle isostatic response (2 - 10 cm) to the semi-diurnal coastal tides, however it remains at an almost uniform depth (within 1 m) despite significant water table variations (> 1 m). Thus, the FWL volume changes in direct proportion to the water table elevation. Previous Yucatan water budgets indicate that 15 % of precipitation recharges the aquifer, however this study shows that > 30 % is required to provide the observed coastal discharge. At least two flow regimes occur within the SWZ. Shallow SWZ flow (to ~ 5 m below the MZ) circulates with alternating periods of net inflow and outflow depending on the mean sea level. This regional reversing flow is substantiated by the inflow of warm marine water at the coast and a pattern of decreasing temperature along the flowpath with distance inland. At greater depth below the MZ (~ 5 - 45 m), saline water flows continuously inland irrespective of sea level. It is proposed that deeper saline flows may represent a cross-platform saline circulation, driven principally by a large east-west ocean head difference (~ 20 - 40 cm).

Spatial heterogeneity of the soil cover in the Yucatan karst: Comparison of Mayan, WRB, and numerical classifications, 2005, Bautista F, Azgarrido S, Castillogonzalez M, Zinck Ja,
In karstic areas, geopedologic information integrating soil and relief features, especially concerning short-distance variability, is usually scarce. The aim of this paper was to compare soil classes in the Yucatan karst using the Mayan soil nomenclature, the World Reference Base for Soil Resources (WRB), numerical soil classification (NSC), and geostatistics. The landscape is a flat-to-slightly-undulating karstic plain. Soil properties were determined at 54 sampling points on a regular grid covering an area of 1350 m(2). Six indigenous soil classes were identified on the basis of the terrain position, topsoil color, stoniness, rockiness. rock type. and soil depth. Five WRB soil units were recognized belonging mainly to Leptosols. Furthermore, six NSC groups were determined mainly on the basis of organic matter and stoniness. Soil organic material and texture explained 57% of the variation of the soil cover. An isotropic model of organic carbon shows a range of 39 m

GPR detection of karst and archaeological targets below the historical centre of Merida, Yucatn, Mexico, 2009, Barba Luis, Blancas Jorge, Ortiz Agustin, Ligorred Josep

The Historical Center of Merida has been classified as a “zone of high patrimonial value” based on the study of topography and the historical documents that show a long-term occupation, non-interrupted since pre- Columbian times when T’Hó was the great capital of the northern region of the Maya area. For the local government, rehabilitation of the Historical Center of Merida has been a great priority. Among others, this project includes preservation of archaeological remains (pre-Columbian or colonial) and detection of karstic zones under the city. In order to prevent damage to the patrimony, ground penetrating radar (GPR) surveys were carried out employing 200 and 400 MHz antennas along 16.5 km of the city streets. After data analysis, it was possible to build a map showing the locations of subsurface karst features and archaeological remains below the street pavement, many of which correlate with archaeological platforms proposed in historic documents as well as some of the cenotes recorded in popular memory. As result, for the first time in Mexico, a local government has information available that will allow them to minimize damage to archaeological remains and mitigate risks associated with construction above shallow subsurface karstic zones within this important modern city

Results 16 to 30 of 37
You probably didn't submit anything to search for