Saline Minerals

2017 ◽  
pp. 101-125
Author(s):  
J. Wallace Gwynn
Keyword(s):  
1983 ◽  
Vol 40 (3-4) ◽  
pp. 269-277 ◽  
Author(s):  
Mokhtar Rasmy ◽  
Selim F. Estefan
Keyword(s):  

1997 ◽  
Vol 42 (5) ◽  
pp. 406-409 ◽  
Author(s):  
Yingkai Xiao ◽  
Weiguo Liu ◽  
Yinming Zhou ◽  
Dapeng Sun

2021 ◽  
pp. 1-12
Author(s):  
Weilin Zhang ◽  
Tao Li ◽  
Xiaomin Fang ◽  
Tao Zhang ◽  
Maodu Yan ◽  
...  

Abstract A closed Quaternary saline paleolake, currently still a lake and named Dalangtan after one of its largest sub-basins, has widely distributed sediments in the western Qaidam Basin, NE Tibetan Plateau. Lacustrine salt minerals and fine sediments from this paleolake provide an environmental record for investigating paleoclimatic evolution in the Asian interior. However, detailed continuous Pliocene–Quaternary paleoclimatic records are broadly lacking from the NE Tibetan Plateau owing to poor exposure of the outcrops in section. For this study, we performed a detailed magnetostratigraphic dating and rock magnetic analysis on a 590-m-long core from the SG-5 borehole in the western Qaidam Basin. The results demonstrate that the lacustrine sediments in the SG-5 borehole were deposited more than ~3.0 Ma. Saline minerals began to increase at 1.2 Ma, and the magnetic susceptibility (χ) also changed at that time; the percentage frequency-dependent magnetic susceptibility was relatively low and uniform throughout the whole core. These observations, combined with the χ, pollen, salt ion, and grain-size records from other boreholes, indicate that the western Qaidam Basin and the greater Asian interior had a significant climate transition at 1.2 Ma during an extreme drought.


In a former paper I mentioned that saline minerals were often comparatively free from contamination with radio-active material of the uranium-radium series. Accordingly they afford special opportunities of testing whether or not helium is generated by the other elements present, namely, sodium, potassium, magnesium, calcium, sulphur, chlorine, oxygen, hydrogen. In this paper determinations are given of helium and radium in some of the saline minerals of Stassfurt. These minerals occur in strata of triassic age, though the age of some of them may be less, for there is evidence that secondary alterations have taken place in the salt deposits. Helium was liberated by solution of the mineral in water. The powdered substance was placed in a flask fitted up as shown in the preceding paper. The flask was exhausted, washed out with oxygen, again exhausted, and sealed off from the pump. Water, well boiled, and allowed to cool in a vacuum, was admitted through a tap. Heat was applied to promote solution, and when this was complete the gases set free were driven out by boiling and collected over mercury. Carbonic acid was removed by potash, and other constituents by sparking. The small residue was then examined as described in ‘Roy. Soc. Proc.,’ A, vol. 80, p. 592, liquid air being generally used to cool the charcoal.


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