U.S. Geological Survey Karst Interest Group Proceedings, San Antonio, Texas, May 16–18, 2017

Abstract

For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment-visit https://www.usgs.gov/ or call 1-888-ASK-USGS (1-888-275-8747).For an overview of USGS information products, including maps, imagery, and publications, visit https://store.usgs.gov.Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner.Suggested citation: Kuniansky, E.L., and Spangler, L.E., eds., 2017, U.S. Geological Survey Karst Interest Group Proceedings, San Antonio, Texas, May 16-18, 2017: U.S. Geological Survey Scientific Investigations Report 2017-5023, 245 p., https://doi.org/10.3133/sir20175023. ISSN 2328-0328 (online) iii Contents Introduction and AcknowledgmentsKarst aquifer systems are present throughout parts of the United States and some of its territories, and have developed in carbonate rocks (primarily limestone and dolomite) and evaporites (gypsum, anhydrite, and halite) that span an interval of time encompassing more than 550 million years. The depositional environments, diagenetic processes, post-depositional tectonic events, and geochemical weathering processes that form karst aquifers are varied and complex. These factors involve biological, chemical, and physical changes that when combined with the diverse climatic regimes in which karst development has taken place, result in the unique dual-or triple-porosity nature of karst aquifers. These complex hydrogeologic systems typically represent challenging and unique conditions to scientists attempting to study groundwater flow and contaminant transport in these terrains.The dissolution of carbonate rocks and the subsequent development of distinct and beautiful landscapes, caverns, and springs have resulted in the most exceptional karst areas being designated as national or state parks. Tens of thousands of similar areas in the United States have been developed into commercial caverns and known privately owned caves. Both public and private properties provide access for scientists to study the flow of groundwater in situ. Likewise, the range and complexity of landforms and groundwater flow systems associated with karst terrains are enormous, perhaps more than for any other aquifer type. Karst aquifers and landscapes that form in tropical areas, such as the cockpit karst along the north coast of Puerto Rico, differ greatly from karst landforms in more arid climates, such as the Edwards Plateau in west-central Texas or the Guadalupe Mountains near Carlsbad, New Mexico, where hypogenic processes have played a major role in speleogenesis. Many of these public and private lands also contain unique flora and fauna associated with these karst hydrogeologic systems. As a result, numerous federal, st...

Deciphering landscape evolution with karstic networks: A Pyrenean case study

“…This finding is coherent with the 26 Al/ 10 Be-deduced burial duration, which was roughly 2 times lower than the 10 Be/ 21 Nededuced burial duration. Regarding the second proposition, mixtures of sediments of different ratios may occur between two levels that are linked by a vertical connection or may result from external events, such as (i) more pronounced basal stagnation phases (as it is potentiality the case in Arkansas (Keen-Zebert et al, Paces et al, 2017)) with the remobilization of previous deposits; or (ii) substantial fluctuations in the base level, which led to the partial reuse of the ducts, remobilization of previous deposits, and potential refreshment of the morphologies. Indeed, if the sediments have not had time to consolidate, their remobilization may have erased old morphologies.…”