We observed a layer of cave ice on the water in cave without a name upstream passage this January. I don't recall seeing any on trips we did back in 2000.
On Feb 13, 2012, at 7:45 PM, Mark Minton <mmin...@caver.net> wrote: > In a similar vein, back in the '80s in Spring Creek Cave (TX) I > remember breaking through calcite ice that had formed a solid layer on the > surface of the water in active stream passage. We crunched through it > sinking large pieces as we walked. A few months later when we returned the > solid layer of calcite had already reformed on the water. I do not remember > the times of year that those trips took place, but obviously calcite > rafts/ice can form very rapidly under optimal conditions. > > Mark > > At 04:36 PM 2/13/2012, George Veni wrote: >> I've been thinking a lot about Snowy, and its situation is different from >> Honey Creek. Calcite precipitation on the floor of Honey Creek occurs mostly >> by sunken rafts, whereas calcite in Snowy is precipitated as a crystalline >> layer on the submerged walls and floors. The basic geochemical equations and >> processes are the same, but there are some important differences that affect >> the methods of deposition. I've not seen any water chemistry data for Snowy >> and no such data exists for how the water evolves as it flows down the >> passage. Also missing, at least to my eyes, is information on carbon dioxide >> in the air and water at Snowy. Lastly, the source area for Honey Creek's >> water is fairly well understood, which is not the case for Snowy. >> >> I'm not discouraging research, only pointing out how much more needs to be >> done. So much karst. So little time... >> >> George >> >> *************************** >> >> George Veni, Ph.D. >> Executive Director >> National Cave and Karst Research Institute >> 400-1 Cascades Avenue >> Carlsbad, New Mexico 88220-6215 USA >> Office: 575-887-5517 >> Mobile: 210-863-5919 >> Fax: 575-887-5523 >> gv...@nckri.org >> www.nckri.org >> >> -----Original Message----- >> From: Pete Lindsley [mailto:caverp...@gmail.com] >> Sent: Monday, February 13, 2012 13:26 >> To: gv...@nckri.org >> Cc: 'texas cavers' >> Subject: Re: [Texascavers] Honey Creek sand observation >> >> George, it would also be interesting to relate this to the development of >> the rather recent calcite formation in Snowy RIver. SR only forms calcite in >> SR during a "flood event" in the really dry NM area, and that apparently >> happens only 2-4 times in a 10 year period due mostly to heavy rains and >> heavy snow melts. >> >> So we have two "Laboratory Caves" here, one in dry NM, and the other in a >> much wetter TX area. >> >> - Pete >> >> On Feb 13, 2012, at 1:17 PM, George Veni wrote: >> >> Measurements I made of soil and cave air carbon dioxide during my >> dissertation research in the Honey Creek area show a strong positive >> correlation between spring-summer plant growth and increases in cave air >> carbon dioxide. Studies in other areas have shown the same thing. >> >> You are correct that the water temperature has an effect, as do seasonal >> changes in water chemistry, both of which I didn't mention for the sake of >> brevity. I would expect that a decrease in temperature would result in >> dissolution of the rafts rather than the precipitation we see. However, >> because the water temperature has usually come close to equilibrating with >> the temperature of the surrounding mass of rock and water by the time we see >> it in the areas where rafts are deposited, I would also expect any >> temperature effects to be minor given the small decrease in temperature. I >> have measured significant changes in carbon dioxide and know that is >> certainly a major factor. >> >> It would be interesting to run a "standard" example of the cave's water >> chemistry values through a geochemical model and tweak the temperature and >> carbon dioxide levels over a series of iterations to predict how much of a >> change in temperature or carbon dioxide would be needed to affect raft >> deposition one way or the other. >> >> George >> >> *************************** >> >> George Veni, Ph.D. >> Executive Director >> National Cave and Karst Research Institute >> 400-1 Cascades Avenue >> Carlsbad, New Mexico 88220-6215 USA >> Office: 575-887-5517 >> Mobile: 210-863-5919 >> Fax: 575-887-5523 >> gv...@nckri.org >> www.nckri.org >> >> -----Original Message----- >> From: Diana Tomchick [mailto:diana.tomch...@utsouthwestern.edu] >> Sent: Monday, February 13, 2012 12:40 >> To: <gv...@nckri.org> >> Cc: texas cavers >> Subject: Re: [Texascavers] Honey Creek sand observation >> >> > The degree to which the sand accumulates or is noticed at any given >> > time depends mostly on: >> > . How much time has passed since the last flood, which determines >> how many rafts will accumulate floating on the water; >> > . How severe the flood was, and did it just sink the floating >> rafts where they can be seen, or wash them away or bury them under silt and >> clay where they will not be seen; >> > . The chemistry of the cave's water and atmosphere to create >> favorable conditions for raft development. Kurt is right that they usually >> form more quickly in the winter because the cave atmosphere has less carbon >> dioxide at that time, allowing more carbon dioxide to degas from the water, >> driving the water to supersaturation with respect to calcite, and promoting >> calcite raft development. >> >> Does the cave atmosphere have less carbon dioxide due to lesser amounts of >> degradation of biomass in the ground over the cave in the winter (due to the >> lower surface air temperatures), or is it due to a reduction in temperature >> of the creek water in the cave? Because the solubility of carbon dioxide >> increases as the temperature of water decreases. >> >> Diana > > Please reply to mmin...@caver.net > Permanent email address is mmin...@illinoisalumni.org > > --------------------------------------------------------------------- > Visit our website: http://texascavers.com > To unsubscribe, e-mail: texascavers-unsubscr...@texascavers.com > For additional commands, e-mail: texascavers-h...@texascavers.com > --------------------------------------------------------------------- Visit our website: http://texascavers.com To unsubscribe, e-mail: texascavers-unsubscr...@texascavers.com For additional commands, e-mail: texascavers-h...@texascavers.com
