The Geological Society of America Council has approved the creation of the Karst Division at its annual meeting on Wednesday, October 22.
On Thursday October 2, 2014 the membership in the Speleogenesis Network has reached 1000 ! The lucky registration was by Jim Goodbar of US, - welcome, and congratulations!
Cecilio López-Tercero, profesional speleologist was injured during the exploration of the karst system in Leymebamba, Amazonas, located in the Andean Cordillera.
The session on evaporite karst will be held at the South-Central Section, Geological Society of America (GSA) meeting in Stillwater, OK, on March 19-20, 2015.
The State of Minnesota has positions open for hydrologists. These positions include some for hydrogeologists.
Did you know?
That brittle deformation is the sudden failure of a rock with complete loss of cohesion across a plane.?
Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms
Featured article from geoscience journal
A large number of uniform cone-shaped dissolution pipes has been observed and studied in Quaternary coastal calcareous arenites in Apulia and Sardinia (Italy) and Tunisia. These cylindrical tubes have a mean diameter of 52·8 cm and are up to 970 cm deep (mean depth for sediment-free pipes is 1·38 m). They generally have smooth walls along their length, are perfectly vertical and taper out towards their bottoms. Their development is not influenced by bedding nor fractures. Sometimes their walls are coated by a calcrete crust. Their morphology has been studied in detail and their relationships with the surrounding rocks and with the environment have been analysed. The perfectly vertical development is a clear evidence of their genesis controlled by gravity. The depth of the dissolution pipes can be described by an exponential distribution law (the Milanovic distribution), strongly suggesting they developed by a diffusion mechanism from the surface vertically downward. We believe dissolution pipes preferentially form in a covered karst setting. Local patches of soil and vegetation cause infiltration water to be enriched in carbon dioxide enhancing dissolution of carbonate cement and local small-scale subsidence. This process causes the formation of a depression cone that guides infiltrating waters towards these spots giving rise to the downward growth of gravity-controlled dissolution pipes. A change of climate from wetter phases to drier and hotter ones causes the formation of a calcrete lining, fossilizing the pipes. When the pipes become exposed to surface agents by erosion of the sediment cover or are laterally breached the loose quartz sand filling them may be transported elsewhere.