Mixing hyperbola

Table 1.7b. Some parameters of the mixing hyperbola shown in Figure 1.6. ...

Barling and Goldstein (1989) have measured Pb and Sr isotope compositions in recent lavas from Heard Island (Southern Indian Ocean). They obtained the data listed in Table 5.6. Find the parameters of a least-square mixing hyperbola fitting the observations. 

Figure 5.5 Least-square mixing hyperbola for the isotopic data on Heard Island of Barling and Goldstein (1989). Data from Table 5.10. The 87Sr/86Sr value of the MORB source ( 0.7025) lies below the horizontal asymptote. Asthenosphere and oceanic lithosphere are unlikely source components of Heard Island basalts.

The mixing hyperbola has been drawn in Figure 5.5. The two asymptotes intersect... 

Figure 6.1 gives an example of a mixing hyperbola in a ratio vs. ratio plot. 

Figure 12. Comparison of 5 O values with Srr Sr ratios in representative ocean-island basalts, organized by sub-type as defined by radiogenic isotope systematics (see Fig. 11 data from Filer et al. 1996a). Low- HeAle lavas are a special case discnssed in Filer et al. (1996a) and in the text of this chapter and are exclnded here. The heavy dashed craves mark the range of mixing hyperbolae between depleted mantle (based on data for NMORBs Figs. 9 and 10) and high-o 0 siliciclastic sediments.

Fig. 16.24 The soil salts along the coast of Ross Island contain strontium and sulfur that originated from the volcanic rocks and from seawater. The isotopic compositions of strontium and sulfur in the soil salts are constrained by two isotopic mixing hyperbolas whose shapes depend on the assumed concentrations of strontium and sulfur expressed by the parameter K. The iso-...

The salts in the soil of Ross Islands contain strontium and sulfur both of which are mixtures of two components that have different isotope compositions. Such mixtures are described by an equation that was derived by Langmuir et al. (1978) and presented by Faure (1986). The procedure is to calculate the Sr/ Sr ratio and 8 S value separately for the same mixing parameters. The results are the coordinates of points on the Sr-S mixing hyperbola which can be constructed by means of a smooth curve through the points calculated from the mixing equations ... 

The curvature and attitude of the mixing hyperbola depend on the concentration ratios of the two elements X and Y which are related by the equation ... 

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