Instruments And Manufacturing In Vegas -- SIS3 Will Leave With No Regards

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Версія від 13:56, 16 липня 2017, створена Cell0linda (обговореннявнесок) (Створена сторінка: Activities are orders of magnitude less than for dissolved 222Rn, showing that Ra contents are not recoil-dominated as they are for 222Rn. The highest Ra activi...)

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Activities are orders of magnitude less than for dissolved 222Rn, showing that Ra contents are not recoil-dominated as they are for 222Rn. The highest Ra activities appear positively correlated with Ca and Ba contents. U-contents and 234U/238U activity ratios following a flow line NW�CSE from the M'Zab Ridge in the Algerian CI identify a redox zone downgradient where A.R.s are enhanced as dissolved U-contents decrease to ATP12A times up to ?600?ka; the distance between Hassi Messaoud and Rhourde El Baguel (some 100?km) apparently taking ?65?ka. In Tunisia, a similar trend U-contents and 234U/238U activity ratios is suggested going S�CN and implicating a recharge direction from the Tinrhert Plateau of SE Algeria or the Tunisian Dahar Hills towards the Chott Fedjej discharge zone, as indicated also by the aquifer piezometry. This trend indicates also a redox barrier occurring in this S�CN direction. Age modelling of the 234U/238U evolution suggests geochemical residence times ?20?ka between Menchia and Chott El Fedjej in Tunisia. The paleoage status of these Algerian and Tunisian waters is supported by simple modelling of 4He accumulation (and 4He/222Rn) in the waters which suggest water ages of the order tens of thousands up to 1?Ma old. The palaeowater status of these waters is supported also by recharge temperatures measured for the CI AZD3759 research buy waters, which are generally cooler than current Climate Normal values for annual temperature in the region and in the case of Gassi Touil (RT???15?��C) indicate recharge under significantly cooler (past) climate conditions. The 234U/234U activity ratios seen in waters from both the SIS3 in vitro Algerian and Tunisian aquifers therefore support previous 14C and 36Cl age estimates that identify the Continental Intercalaire waters from the M'Zab ridge towards the centre of the Grand Erg Oriental sub-basin in Algeria as being palaeowaters, and similarly for waters in the locality of Chott Fedjej to the East of the major horst structure that occurs around Chott Djerid in Tunisia. Finally, old water ages (residence times) are suggested also for the few Complexe Terminal (CT) waters presented from Algeria and Tunisia, since these samples again have enhanced (radiogenic) 4He contents. For the regions studied therefore these waters should be regarded as ��fossil�� waters and treated effectively as a non-renewable resource. Nevertheless, any such geochemical residence time estimates may require reconciliation with hydraulic and emerging geophysical approaches, especially on the margins as recognised by Gon?alv��s et?al. (2013).