Merge pull request #81 from brenhinkeller/jyao-statgeochem-branch

update Ayers sphene saturation functions

Author: brenhinkeller

src/utilities/Geochemistry.jl

@@ -519,36 +519,87 @@
         return (10 * eCa) / (Al * Si)
     end
 
-    """
+    function Ayers_tspheneM(SiO2::Number, TiO2::Number, Al2O3::Number, FeOT::Number, MnO::Number, MgO::Number, CaO::Number, Na2O::Number, K2O::Number, P2O5::Number)
+        #Cations
+        Na = Na2O/30.9895
+        K = K2O/47.0827
+        Ca = CaO/56.0774
+        Al = Al2O3/50.9806
+        Si = SiO2/60.0843
+        Ti = TiO2/79.865
+        Fe = FeOT/71.8444
+        Mg = MgO/24.3050
+        Mn = MnO/70.9374
+        P = P2O5/70.9723
+
+         # Normalize cation fractions
+        normconst = nansum((Na, K, Ca, Al, Si, Ti, Fe, Mg, Mn, P))
+        K, Na, Ca, Al, Si = (K, Na, Ca, Al, Si) ./ normconst
+
+        M = (Na + K + (2 * Ca))/(Al * Si)
+        return M
+    end
+
+     """
     ```julia
     TiO2Sat = Ayers_tspheneTiO2(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5, T)
     ```
     Calculate sphene saturation TiO2 concentration (in wt. %) for a given temperature
+    (in C) following the sphene saturation calibration of Ayers et al., 2022
+    (doi: 10.1007/s00410-022-01902-z)
+    """
+    function Ayers_tspheneTiO2(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5, TC)
+        M = Ayers_tspheneM(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5)
+        TiO2 = max((0.978*M)+(0.0048*(TC+273.15))-5.90, 0)
+        return TiO2
+    end
+    export Ayers_tspheneTiO2
+
+    """
+    ```julia
+    TC = Ayers_tsphene(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5)
+    ```
+    Calculate sphene saturation temperature in degrees Celsius
+    Following the sphene saturation calibration of Ayers et al., 2022
+    (doi: 10.1007/s00410-022-01902-z)
+    """
+    function Ayers_tsphene(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5)
+        M = Ayers_tspheneM(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5)
+        TC = (TiO2 + 5.90 - (0.978*M))/0.0048 - 273.15
+        return TC
+    end
+    export Ayers_tsphene
+
+    """
+    ```julia
+    TiO2Sat = Ayers_tspheneTiO2_18(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5, T)
+    ```
+    Calculate sphene saturation TiO2 concentration (in wt. %) for a given temperature
     (in C) following the sphene saturation calibration of Ayers et al., 2018
     (doi: 10.1130/abs/2018AM-320568)
     """
-    function Ayers_tspheneTiO2(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5, TC)
+    function Ayers_tspheneTiO2_18(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5, TC)
         C = Ayers_tspheneC(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5)
         TiO2 = max(0.79*C - 7993/(TC+273.15) + 7.88, 0)
         return TiO2
     end
-    export Ayers_tspheneTiO2
+    export Ayers_tspheneTiO2_18
 
 
     """
     ```julia
-    TC = Ayers_tsphene(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5)
+    TC = Ayers_tsphene_18(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5)
     ```
     Calculate sphene saturation temperature in degrees Celsius
     Following the sphene saturation calibration of Ayers et al., 2018
     (doi: 10.1130/abs/2018AM-320568)
     """
-    function Ayers_tsphene(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5)
+    function Ayers_tsphene_18(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5)
         C = Ayers_tspheneC(SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5)
         TC = 7993/(0.79*C - TiO2 + 7.88) - 273.15
         return TC
     end
-    export Ayers_tsphene
+    export Ayers_tsphene_18
 
 ## --- Rutile saturation calculations
 

test/testGeochemistry.jl

@@ -87,10 +87,13 @@
     @test tzircZr(majors..., 800) ≈ 826.1071302971219
     @test mean(tzircM((repeat([m],2) for m in majors)...,)) ≈ 2.328787411099651
 
-    @test StatGeochem.Ayers_tsphene(majors...) ≈ 637.7486728299519
-    @test StatGeochem.Ayers_tspheneTiO2(majors..., 800) ≈ 2.3486842447760026
+    @test StatGeochem.Ayers_tsphene_18(majors...) ≈ 637.7486728299519
+    @test StatGeochem.Ayers_tspheneTiO2_18(majors..., 800) ≈ 2.3486842447760026
     @test mean(StatGeochem.Ayers_tspheneC.((repeat([m],2) for m in majors)...,)) ≈ 2.4263934899817188
 
+    @test StatGeochem.Ayers_tsphene(majors...) ≈ 694.4428983217797
+    @test StatGeochem.Ayers_tspheneTiO2(majors..., 800) ≈ 1.5286740880554586
+
     #                SiO2,   TiO2,  Al2O3,  FeOT,   MgO,  CaO,   Na2O,  K2O,   Li2O, H2O
     montel_elems = [58.509, 1.022, 14.858, 4.371, 4.561, 5.912, 3.296, 2.399, 0.01, 4.0]
     @test StatGeochem.Montel_tmonaziteREE(montel_elems..., 750.0) ≈ 11.884450325741755