Anemona rock
3.4 x 10 -8 s - 1 corresponding to a mean removal time of radium from brine by mineral precipitation to approximately one year.Īs an inert gas ²²²Rn can be employed as a natural radiotracer for the characterization of hydrogeological properties of geothermal systems. The precipitation rate constant amounts to ca. (3) Scavenging of 226 Ra from brine can best be explained by co-precipitation with barite resulting in an observed 226 Ra anomaly in the solids of the reservoir section. (2) Radium retardation due to adsorption is low ( 226 Ra/ 222 Rn = 1.3) resulting in adsorption-desorption rate constants in the order of 10 -10 s -1 for k 1 and 10 -9 for k 2. Modelling the observed disequilibria allows the following conclusion on water-rock interaction processes: (1) Supply from alpha recoil depends on isotope half-life because it is limited by the rate of diffusion through microfractures causing isotopic fractionation. Activities of radium isotopes in the geothermal brine exceed those of their thorium progenitors (average 226 Ra = 29.9 Bq kg -1, about 10 3 times that of its 230 Th parent). The results show that radionuclides of the elements radium ( 226 Ra, 228 Ra, 224 Ra, 223 Ra), radon ( 222 Rn), and lead ( 210 Pb, 212 Pb) are rather soluble in brine, while isotopes of uranium ( 238 U, 234 U, 235 U), thorium ( 232 Th, 228 Th, 230 Th), polonium ( 210 Po), and actinium ( 227 Ac, 228 Ac) have low solubilities and are mostly immobile.
#Anemona rock series
In this study, we present data from long-term monitoring of naturally occurring 238 U, 232 Th and 235 U series radionuclides analyzed in brine samples collected from the Permo-Triassic sedimentary reservoir rock at the Bruchsal geothermal site (SW Germany). The migratory behavior of radionuclides provides valuable site-specific information and can therefore be an important tool for reservoir characterization and sustainable management of geothermal sites.
![anemona rock anemona rock](https://www.reefcleaners.org/images/stories/virtuemart/product/rock_anemone.jpg)
![anemona rock anemona rock](http://2.bp.blogspot.com/-39kKjTf8nu0/U0mV_DDDMkI/AAAAAAAAAGM/JftW2Y6tKns/s1600/rock.jpg)
Uranium and thorium decay series disequilibria in deep geothermal brines are a result of water-rock interaction processes.