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The Yucatan Peninsula karst aquifer is one of the most extensive and spectacular karst aquifer systems on the planet. This transboundary aquifer system extends over an area of approximately 165,000 km2 in Mexico, Guatemala and Belize. The Triassic to Holocene Yucatan limestone platform is located in the vicinity of the North American/Caribbean plate boundary and has been reshaped by a series of tectonic events over its long geologic history. At the end of the Cretaceous period, the Yucatan Peninsula was hit by a large asteroid, which formed the Chicxulub impact crater. The Yucatan Peninsula karst aquifer hosts large amounts of groundwater resources which maintain highly diverse groundwater-dependent ecosystems. Large parts of the aquifer are affected by seawater intrusion. Anthropogenic pollution of the aquifer has been increasing over the past few decades, owing to relentless economic development and population growth on the Peninsula. This review summarizes the state of knowledge on the Yucatan Peninsula karst aquifer and outlines the main challenges for hydrologic research and practical groundwater-resources management on the Peninsula.
Locating caves can be difficult, as their entranceways are often obscured elow vegetation. Recently, active remote-sensing technologies, in particular laser-based sensor systems (LiDARs), have demonstrated the ability to penetrate dense forest canopies to reveal the underlying ground topography. An airborne LiDAR system was used to generate a 1 m resolution, bare-earth digital elevation model (DEM) from an archaeologically- and speleologically-rich area of western Belize near the ancient Maya site of Caracol. Using a simple index to detect elevation gradients in the DEM, we identified depressions with at least a 10 m change within a circular area of no more than 25 m radius. Across 200 km2 of the karst landscape, we located 61 depressions. Sixty of these had not been previously documented; the other was a cave opening known from a previous expedition. The morphologies of the depressions were characterized based on the LiDAR-derived DEM parameters, e.g., depth, opening area, and perimeter. We also investigated how the measurements change as a function of spatial resolution. Though there was a range of morphologies, most depressions were clustered around an average maximum depth of 21 m and average opening diameter of 15 m. Five depression sites in the general vicinity of the Caracol epicenter were visited; two of these were massive, with opening diameters of ,50 m, two could not be explored for lack of climbing gear, and one site was a cave opening into several chambers with speleothems and Maya artifacts. Though further investigation is warranted to determine the archaeological and geological significance of the remaining depressions, the general methodology represents an important advancement in cave detection.
The Yucatán Peninsula karst aquifer is one of the most extensive and spectacular karst aquifer systems on the planet. This transboundary aquifer system extends over an area of approximately 165,000 km2 in México, Guatemala and Belize. The Triassic to Holocene Yucatán limestone platform is located in the vicinity of the North American/Caribbean plate boundary and has been reshaped by a series of tectonic events over its long geologic history. At the end of the Cretaceous period, the Yucatán Peninsula was hit by a large asteroid, which formed the Chicxulub impact crater. The Yucatán Peninsula karst aquifer hosts large amounts of groundwater resources which maintain highly diverse groundwater-dependent ecosystems. Large parts of the aquifer are affected by seawater intrusion. Anthropogenic pollution of the aquifer has been increasing over the past few decades, owing to relentless economic development and population growth on the Peninsula. This review summarizes the state of knowledge on the Yucatán Peninsula karst aquifer and outlines the main challenges for hydrologic research and practical groundwater-resources management on the Peninsula
Karst is inherently dynamic, and this may be manifest in unexpected ways, which may have major implications for management of protected areas, where changes may have major impacts on visitor numbers and revenue streams. In Five Blues Lake National Park, Belize, the principal visitor focus is Five Blues Lake itself. An anomalous feature with characteristics of a karst window or cenote but in the setting of a polje or ponor lake, Five Blues has both surface and underground drainage components. Establishment of the national park proceeded under the impression that the lake was a permanent feature, but over July 20 to 25, 2006, the lake drained rapidly underground. Without the lake, visitor numbers and park revenues declined, and the park was all but abandoned. The lake refilled in 2007, but visitor numbers continue to lag. Management and promotion of hydrologic features within protected areas needs to take such possibilities into account, emphasizing variability and change and avoiding a focus on conditions that may not prevail at any given time.
Archaeological investigations of the Overlook Rockshelter in the Caves Branch River Valley of central Belize offer a unique view of ancient Maya cave ritual through the complete recovery and analysis of all artifacts within the site’s two small activity areas. In general, the assemblage contains many of the same types of objects documented from other nearby caves and rockshelters. However, the nearly 1700 ceramics sherds showed almost no refits, demonstrating that sherds were deposited at the site individually, rather than as complete vessels. The human bone assemblage represents three or four individuals, with the majority of the bones comprising a single individual, and all of these were deposited as incomplete secondary interments. Analogies for this depositional behavior based on archaeological and ethnographic studies suggest that this rockshelter may represent a waypoint within a ritual circuit composed of multiple locations over which fragments of complete items such as ceramic vessels and secondary burials were spread.
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