Lake Cave

As water slowly dissolves the limestone roof of a cave, the roof becomes weak and may eventually collapse. The result Is a sinkhole. When a source of water remains, the sinkhole fills to form a lake that can be very scenic. 

GB-89-24-1 (DCF corrected) GB-89-24-1 spline Cango Caves Lake Lisan Mururoa Barbados Lake Suigetsu Papua Nevi/ Guinea Icelandic Sea... 

Obviously this wide distribution of the 14C formed in the atmosphere lakes time it is believed to require a period of 500-1000 years. This time is not. however, a deterrent to radiocarbon dating because of two factors die long half-life of I4C and the relatively constant rate of cosmic-ray formation of l4C in the earth s atmosphere over the most recent several thousands of years. These considerations lead to the conclusion that the proportion of 14C in the carbon reservoir of the earth is constant, and that the addition by cosmic ray production is in balance with the loss by radioactive decay. If this conclusion is warranted, then the carbon dioxide on earth many centuries ago had the same content of radioactive carbon as the carbon dioxide on earth today, Thus, radioactive carbon in the wood of a tree growing centuries ago had the same content as that in carbon oil earth today. Therefore, if we wish to determine how long ago a tree was cut down to build an ancient fire, all we need to do is to determine the relative 14C content of the carbon in the charcoal remaining, using the value we have determined for llie half life of 14C. If the carbon from Ihe charcoal in an ancient cave has only as much 14C radioactivity as does carbon on earth today, then we can conclude that the tree which furnished llie firewood grew 5730 30 years ago. 

Consistent with the measured cave air temperatures, Sparmagel Cave lakes perermial ice, expect for a neighboring cave (near the main entrance of Sparmagel Cave) that contains a small accumulation of ice, the volume of which has steadily decreased dining the past few years. 

The minerals nesquehonite through huntite in Table 6.1 are comparatively rare. Among these only hydromagnesite can precipitate in water at 25°C and atmospheric CO2 pressures (Fig. 6.2). Because of their high solubilities, the Mg-carbonate and hydroxy-carbonate minerals, are generally uncommon except in some evaporative cave pools, evaporating ocean embayments, arid soils, and closed-basin lakes (cf. Hostetler 1964). Nesquehonite is about 24 times as soluble as calcite at 25°C and a CO2 pressure of I bar. Similarly, at atmospheric CO2 pressure (10 bar) the solubility of hydromagnesite is 5.5 mmol/kg, whereas that of calcite is only 0.52 mmol/kg. 

Clottes. Jean (ed.) 2003. Chauvet Cave The Art of Earliest Times. Salt Lake City University of Utah Press. 

Consider just a few cases of aqueous equilibria. The magnificent formations i n limestone caves and the vast expanses of oceanic coral reefs result from subtle shifts in carbonate solubility equilibria. Carbonates also influence soil pH and prevent acidification of lakes by acid rain. Equilibria involving carbon dioxide and phosphates help organisms maintain cellular pH within narrow limits. Equilibria involving clays in soils control the availability of ionic nutrients for plants. The principles of ionic equilibrium also govern how water is softened, how substances are purified by precipitation of unwanted ions, and even how the weak acids in wine and vinegar influence the delicate taste of a fine French sauce. In this chapter, we explore three aqueous ionic equilibrium systems acid-base buffers, slightly soluble salts, and complex ions. 

Travertine 1) Any finely crystalline massive concretionary limestone formed by surface or groundwater evaporation. 2) Any flowstone deposit, hence the usage travertine implying stalagmitic flowstone. 3) Any carbonate deposit formed within a cave or karst system by secondary precipitation. 4) Massive, hard, dense carbonate deposits formed in association with open-air springs, streams, lakes, or marshes that precipitate carbonate. 

Kyle et al. (1982a) recorded the volcanic activity on the summit of Erebus from January 1973 until December 1976. During this time, the lava lake increased substantially and strombolian gas eruptions occurred at the rate of one to three per day. Kyle et al. (1982a) also monitored the seismic activity of the summit area by means of seismographs that were installed in a warm ice cave originally described by Giggenbach (1976). The frequency of volcanic earthquakes in December of 1974 was about 1,0001984 per week (Dibble et al., 1989). 

The eruption of Mt. Mazama in southern Oregon, which formed the crater now called Crater Lake, was determined to have occurred 6453 250 years ago, by the dating of charcoal from a tree killed by the eruption. Three hundred pairs of woven rope sandals found in Fort Rock Cave, Oregon, which had been covered by an earlier eruption, were found... 

A similar event two years earlier at Lake Monoun had killed 37 people. There are caves like the Grotta del Cane (Cave of the dogs), near Naples, where a carpet of COg at floor level will suffocate a dog, but not its (taller) owner. Levels of COg in air much more than 5% are dangerous to health. 

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