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Full-Text Articles in Earth Sciences
Klimchouk’S Impact On The Development Of Speleogenetic Models For Castile Evaporites: West Texas And Southeastern New Mexico, Usa, Kevin W. Stafford
Klimchouk’S Impact On The Development Of Speleogenetic Models For Castile Evaporites: West Texas And Southeastern New Mexico, Usa, Kevin W. Stafford
International Journal of Speleology
Due to the pioneering work of Alexander Klimchouk (2007), hypogene karst is now recognized as being complex and extensive throughout Permian strata of the greater Delaware Basin in West Texas and southeastern New Mexico (USA). Klimchouk heavily influenced our current understanding of hypogene speleogenesis in the Permian Ochoan Castile Formation where we now recognize diverse hypogene manifestations that include vertically-extensive breccia pipes, laterally-extensive blanket breccias, morphologically-varied caves, diagenetically-altered sulfates, and unique venting structures. Underlying Bell Canyon strata provide the transmissive zone for delivery and removal of solutionally aggressive fluids to the conformably overlying Castile evaporites. Current speleogenetic models indicate that …
The Impact Of Burning On The Structure And Mineral Composition Of Bat Guano, Joyce Lundberg, Donald A. Mcfarlane
The Impact Of Burning On The Structure And Mineral Composition Of Bat Guano, Joyce Lundberg, Donald A. Mcfarlane
International Journal of Speleology
Here we addressed the question of whether burning of guano produces a characteristic suite of morphological changes and/or unique mineralogical products. The changes observed in our experimental burning of guano (both fresh and decayed) included colour change (blackening), grain size and morphological change (grain size generally reduced, morphology rendered generally less distinct), alteration of minerals by dehydration (e.g., gypsum to anhydrite, brushite to whitlockite), and production of new minerals or compounds (e.g., augelite, bayerite, giniite, graphite, oldhamite, strontium apatite, tridymite). The key morphological feature we found that may be diagnostic of burning was severe damage to crystals from rapid dehydration …
Sulfur (34S/32S) Isotope Composition Of Gypsum And Implications For Deep Cave Formation On The Nullarbor Plain, Australia, Matej Lipar, Mateja Ferk, Sonja Lojen, Milo Barham
Sulfur (34S/32S) Isotope Composition Of Gypsum And Implications For Deep Cave Formation On The Nullarbor Plain, Australia, Matej Lipar, Mateja Ferk, Sonja Lojen, Milo Barham
International Journal of Speleology
Large deep caves with little relation to surface topography are distinctive karst features on the Nullarbor Plain of Australia. The presence of gypsum deposits and chemoautotrophic bacteria within the caves have been suggested as evidence for cave formation and (or) enlargement via sulfuric acid speleogenesis. To test this hypothesis, the stable sulfur isotope compositions (δ34S) of both cave gypsum and surface gypsum were measured. Analyses yielded relatively high, positive δ34S values from both cave gypsum and surface gypsum, arguing against gypsum genesis via microbial chemoautotrophy, and more broadly, sulfuric acid speleogenesis. Instead, the gypsum is interpreted …
Genesis Of Schlottenkarren On The Avon Peninsula Of Nova Scotia (Canada) With Implications For The Geochronology Of Evaporite Karsts And Caves Of Atlantic Canada, Max Moseley
International Journal of Speleology
Exposed schlottenkarren karst terrains developed on gypsum-anhydrite evaporites in the Canadian Maritime provinces might be post-Glacial landscape features (formed on glacially-denuded rocks after they are uncovered by progressive erosion of overlying glacial tills) or exhumed pre-Last Glacial Maximum (LGM) morphologies (filled with glacial till and revealed by erosion of the tills). In this paper the hydrological conditions necessary for the formation of schlottenkarren, the speleogenetic processes involved and their chronology are reconsidered and reinterpreted. It is proposed that they are essentially pre-LGM features which have survived from the Wisconsinan. It is concluded that the degree of glacial scouring and denudation …
Speleothem Microstructure/Speleothem Ontogeny: A Review Of Western Contributions, William B. White
Speleothem Microstructure/Speleothem Ontogeny: A Review Of Western Contributions, William B. White
International Journal of Speleology
Mineral ontogeny is the study of the growth and development of mineral deposits in general and, in the present context, speleothems in particular. Previous researchers, mainly in Russia, have developed a nomenclatural hierarchy based on the forms and habits of individual crystals and the assembly of individual crystals into both monomineralic and polymineralic aggregates (i.e. speleothems). Although investigations of the growth processes of speleothems are sparse, there is a large literature on growth processes of speleothem minerals and related crystals in the geochemical and materials science literature. The purpose of the present paper is to sort through the various concepts …
Speleothems In The Dry Cave Parts Of The Gamslöcher-Kolowrat Cave, Untersberg Near Salzburg (Austria), Anna Bieniok, Georg Zagler, Uwe Brendel, Franz Neubauer
Speleothems In The Dry Cave Parts Of The Gamslöcher-Kolowrat Cave, Untersberg Near Salzburg (Austria), Anna Bieniok, Georg Zagler, Uwe Brendel, Franz Neubauer
International Journal of Speleology
New, remarkably dry parts of the Gamslöcher-Kolowrat Cave at 728 to 853 m depth have been explored in the Untersberg near Salzburg in Austria. This region is called the Desert, its greatest cavity is called the White Hall. The new cave part is characterized by various white speleothems. The predominant ones are snow-like calcite powder with an extremely low density, and fine gypsum needles. Gypsum also occurs in the form of balls stuck to vertical walls. In addition, fluorescent hydromagnesite crusts, Mg5(CO3)4(OH)2·4H2O, as well as the sodium sulfate mineral mirabilite …
Candoluminescence Of Cave Gypsum, John R. Sweet, John W. Hess, William B. White
Candoluminescence Of Cave Gypsum, John R. Sweet, John W. Hess, William B. White
International Journal of Speleology
A selection of gypsum specimens from a variety of caves as well as CaSO4 synthesized in the laboratory emit both a green and yellow candoluminescence when excited by a hydrogen diffusion flame. The green emission is attributed to dehydration of gypsum to bassanite and the yellow emission appears upon further dehydration to anhydrite. The source of the luminescence is ascribed to minor concentrations of Mn2+ in the gypsum.
Uranium-Series Dating Of Gypsum Speleothems: Methodology And Examples, Laura Sanna, Francisco Saez, Siri Simonsen, Silviu Constantin, José-Maria Calaforra, Paolo Forti, Stein-Erik Lauritzen
Uranium-Series Dating Of Gypsum Speleothems: Methodology And Examples, Laura Sanna, Francisco Saez, Siri Simonsen, Silviu Constantin, José-Maria Calaforra, Paolo Forti, Stein-Erik Lauritzen
International Journal of Speleology
The analytical problems of dating gypsum speleothems with the U-series technique are reviewed. Gypsum speleothems are, in general, very low in U content, challenging the limits of detection methods. Various approaches to dissolving gypsum and isolation of actinides from the matrix include ion-pairing dissolution with magnesium salts and using nitric acid. The most precise dating technique is Thermal Ionization Mass Spectrometry (TIMS), combined with Fe(OH)3 scavenging and anionic exchange chromatography. Less satisfactory, but much quicker, is direct retention of actinides from HNO3 by means of TRU resin and MC-ICP-MS detection. We have tested these methods on gypsum speleothems …
Identification Of Cave Minerals By Raman Spectroscopy: New Technology For Non-Destructive Analysis, William B. White
Identification Of Cave Minerals By Raman Spectroscopy: New Technology For Non-Destructive Analysis, William B. White
International Journal of Speleology
The identification of minerals from caves generally requires that samples be removed from the cave for analysis in the laboratory. The usual tools are X-ray powder diffraction, the optical microscope, and the scanning electron microscope. X-ray diffraction gives a definitive fingerprint by which the mineral can be identified by comparison with a catalog of reference patterns. However, samples must be ground to powder and unstable hydrated minerals may decompose before analysis is complete. Raman spectroscopy also provides a fingerprint useful for mineral identification but with the additional advantage that some a-priori interpretation of the spectra is possible (distinguishing carbonates from …