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Weathering and Soils
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
On a regional scale, dissolution of limestone can lead to a distinct form of topography, called karst topography, that includes many sinkholes, caves, and springs. If the calcite later reprecipitates, caves may become adorned with formations called speleothems, including flowstone, draperies, stalactites, or stalagmites. Precipitation of calcite also accounts for travertine and tufa deposited at hot springs and in lakes, and for marl that sometimes collects on stream bottoms. Speleothems, travertine, tufa, and marl are all different forms of calcium carbonate. Thus, dissolution and reprecipitation can be significant processes, but are restricted to specific kinds of minerals and rocks.
The problems of constructions on karst - The examples from Slovenia
Published in Barry F. Beck, Felicity M. Pearson, Karst Geohazards, 2018
In the cave, on its walls respectively there were the remains of flowstone and stalagmites. On some places the scallops were preserved even. The cave was filled up by the flood loam and in the lower part of the profile by non-carbonate gravel and sand.
Quaternary uplift and fault movement near Waitomo, North Island, New Zealand
Published in New Zealand Journal of Geology and Geophysics, 2023
The breakdown fan banks up against the cave wall on the southeast side of the chamber. Its collapse impounded the cave stream that previously flowed northeast into and through Holden’s Cavern and an external cliff collapse at the cave exit also blocked its resurgence. The rock pile in Breakdown Chamber acted like a sieve to the ponded water and trapped stream sediment within the boulders. These layered sediments were subsequently exposed during excavation of a new tourist passage through the boulder pile following the former stream route. A calcite flowstone layer had accumulated immediately on top of the waterlain deposits and a sample from the flowstone [collected by S. Barker and S. Suresh] was dated at 37.76 ± 0.58 kyrs (ICPMS analysis by J. Hellstrom, Univ. Melbourne). This provides an age closer to the breakdown event than the basal date from the broken stalagmite. Consequently, the collapse that built the rock fan in the cave occurred around 38,000 years ago.