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Crayback stalagmites have mainly been reported from New South Wales, Australia. Here we document a small crayback in the entrance of Painted Cave (Kain Hitam), part of the Niah Caves complex in Sarawak, Borneo. Measuring some 65 cm in length and 18 cm in height, this deposit is elongate in the direction of the dominant wind and thus oriented towards the natural tunnel entrance. It shows the classic humpbacked long profile, made up of small transverse segments or plates, in this case the tail extending towards the entrance. The dark blue-green colour down the centre suggests that cyanobacterial growth follows the track of the wind-deflected roof drip. The dry silty cave sediment provides material for accretion onto the biological mat. This is the only example known from Borneo and one of the very few known from outside of Australia
Kartchner Caverns, located near Benson, Arizona, USA, is an active carbonate cave that serves as the major attraction for Kartchner Caverns State Park. Low-impact development and maintenance have preserved prediscovery macroscopic cavern features and minimized disturbances to biological communities within the cave.. The goal of this study was to examine fungal diversity in Kartchner Caverns on actively-forming speleothem surfaces. Fifteen formations were sampled from five sites across the cave. Richness was assessed using standard culture-based fungal isolation techniques. A culture-independent analysis using denaturing gradient gel electrophoresis (DGGE) was used to assay evidence of community homogeneity across the cave through the separation of 18S rDNA amplicons from speleothem community DNA. The culturing effort recovered 53 distinct morphological taxonomic units (MTUs), corresponding to 43 genetic taxonomic units (GTUs) that represented 21 genera. From the observed MTU accumulation curve and the projected total MTU richness curve, it is estimated that 51 percent of the actual MTU richness was recovered. The most commonly isolated fungi belonged to the genera Penicillium, Paecilomyces, Phialophora, and Aspergillus. This culturebased analysis did not reveal significant differences in fungal richness or number of fungi recovered across sites. Cluster analysis using DGGE band profiles did not reveal distinctive groupings of speleothems by sample site. However, canonical correspondence analysis (CCA) analysis of culture-independent DGGE profiles showed a significant effect of sampling site and formation type on fungal community structure. Taken together, these results reveal that diverse fungal communities exist on speleothem surfaces in Kartchner Caverns, and that these communities are not uniformly distributed spatially. Analysis of sample saturation indicated that more sampling depth is required to uncover the full scale of mycological richness across spelothem surfaces.
An old guano pile deposited by Macroderma gigas has been examined chemically and mineralogically. Sixteen sectional analyses of a profile are presented and discussed. The main soluble components are P2O5, CaO and SO3 (present as brushite, ardealite, gypsum and collophane) with insoluble quartz. Taranakite occurs as a minor constituent.
Frustration and New Year Caves are active between-caves, paralleling in plan and profile the ephemeral stream bed of the V-shaped valley in which their entrances are found. The main streamsink in this valley system feeds their stream, which in turn supplies Zed Cave, a short outflow cave just outside the mouth of this valley. This modest derangement of surface drainage pattern is in keeping with the caves which show slight vadose modification of epiphreatic cave development. Although these active caves are young, they probably formed prior to a Late Pleistocene cold period (30,000 to 10,000 BP) on the basis of soils evidence. Clown Cave on the brow of the valley, a dry cave with indications of sluggish phreatic development, is related to a planation phase of Middle or Lower Tertiary age before valley incision. Bow and Keyslot Caves are abandoned in and out and outflow caves respectively, formed when the surface stream channel was a few metres above the present valley bottom so they antedate the active river caves a little. This hydrologically independent part of the Cooleman Plain mirrors in most respects the major parts draining to the Blue Waterholes, differing chiefly in the greater proportion of between-caves discovered so far.
Hydrogeology related to geothermal conditions of the Floridan Plateau -- Geologic and geomorphic setting -- The principal artesian zone -- The Boulder zone -- Injection sites in Florida -- The Geothermal regime of the Floridan Plateau -- Vertical temperature profiles in Floridan Aquifer system, geographic distribution of temperature in Floridan Aquifer system -- Surface evidence of thermal upwelling -- Humble-Lowndes-Treadwell No. 1 -- Warm mineral springs sinkhole -- The Mud hole submarine spring -- Comparison of theoretical and field studies -- The Dolomite question and cavity formation, Geothermal gradients below the Floridan Aquifer system -- Heat flow in Florida oil test holes and indications of oceanic crust beneath the Southern Florida-Bahamas Platform -- Spatial distribution of ground water temperature in South Florida -- Regional significance of Florida heat flow values -- Thermal model for the Florida crust -- A Model of subsidence with inhomogeneous heat production.
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