A window in the course of alkaline magma differentiation
conducive to immiscible REE-rich carbonatites

This is an implementation of the model presented in the paper A window in the course of alkaline magma differentiation conducive to immiscible REE-rich carbonatites, Geochimica et Cosmochimica Acta 282 (2020) 297-323.

This modelling predicts the REE concentrations of a carbonatite which may be immiscible at equilibrium with an alkaline magmatic rock, only from the silicate rock major elements and REE compositions. The parameterisation first calculates the Ca partition coefficient (DCaCL/SL ), then the REE partition coefficients (DREECL/SL), and finally the REE concentrations of the potential carbonatite.

The calculated REE concentrations can be normalised to chondrite (McDonough and Sun, 1995).

As an example, we calculate the REE compositions of the carbonatite which may be immiscible with a phono-tephrite dyke from the Lofdal magmatic suite in Namibia (Fig.7 in the paper). The phono-tephrite data are from Bodeving et al. (2017)

{{Minute}} : {{Seconde}}
 Use the console       
 Use the spreadsheet (treatment of vectors)

You can paste your data directly from Excel. Maximum size of vectors : 1000 values.
Silicate melt major element concentration (wt%)

Silicate melt REE concentration (μg/g = ppm)
Tm
Pm


 
     
  {{status}}
 


 
         


If you click on Copy table, table of results will be copied to the clipboard. Afterwards, you can paste the table into Excel for example.
Normalisation to chondrites   Silicate melt major element concentration (wt%)   Silicate melt REE concentration (μg/g = ppm)   DcaCL/SL calculation   DREECL/SL calculation   Calculation of carbonatite REE concentrations (μg/g = ppm)
Graph     Tm Pm   Dcaσ(Dca)   {{outputs[y].label}}σ({{outputs[y].label}}) Tmσ(Tm) {{outputs[y].label}}σ({{outputs[y].label}}) Pmσ(Pm) {{outputs[y].label}}σ({{outputs[y].label}})   {{outputs[y].label}}σ({{outputs[y].label}}) Tmσ(Tm) {{outputs[y].label}}σ({{outputs[y].label}}) Pmσ(Pm) {{outputs[y].label}}σ({{outputs[y].label}})
  {{inputs_show[x].object.value[key]}}   {{inputs_show[x].object.value[key]}} ND {{inputs_show[x].object.value[key]}} ND {{inputs_show[x].object.value[key]}}   {{outputs_show[y].object.value[key]}}{{outputs_show[y].object.uncertainty[key]}}   {{outputs_show[y].object.value[key]}}{{outputs_show[y].object.uncertainty[key]}} NDND {{outputs_show[y].object.value[key]}}{{outputs_show[y].object.uncertainty[key]}} NDND {{outputs_show[y].object.value[key]}}{{outputs_show[y].object.uncertainty[key]}}   {{outputs_show[y].object.value[key]}}{{outputs_show[y].object.uncertainty[key]}} NDND {{outputs_show[y].object.value[key]}}{{outputs_show[y].object.uncertainty[key]}} NDND {{outputs_show[y].object.value[key]}}{{outputs_show[y].object.uncertainty[key]}}


Carbonatite REE compositions, normalisation to chondrites
This is an implementation of the model presented in the paper A window in the course of alkaline magma differentiation conducive to immiscible REE-rich carbonatites, Geochimica et Cosmochimica Acta 282 (2020) 297-323.