Paul Dennis edited discussion_temperature.tex  over 8 years ago

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In contrast the clumped isotope temperature data is in good agreement with several other fluid inclusion studies. For example Atkinson (1983) reported homogenization temperatures for type 2 (62$^{\circ}$-82$^{\circ}$C), type 3 (64.9$^{\circ}$-98.9$^{\circ}$C), type 4 (63.4$^{\circ}$-106$^{\circ}$C) and type 5 (66.3$^{\circ}$-68.3$^{\circ}$C) inclusions in fluorite. Type 1 inclusions have a higher homogenization temperatures of 119.5$^{\circ}$ - 157$^{\circ}$C.  In conclusion the clumped isotope temperatures are in agreement with the reported lower estimates of inclusion homogenization temperatures but significantly lower than the highest reported temperatures. They are also consistent with (i) the isotopic composition of potential fluid sources (see below) and (ii) current basin evolution models for the Edale Gulf with maximum burial depths of five to six km. Formation fluids with temperatures 100^${\circ}$C of 100$^{\circ}$C  plus are readily produced with a normal geothermal gradient of just 25 to 30$^{\circ}$C.km^{-1} rahther rather  than the very elevated gradients implied by the high homogenization temperatures. The differences could be reconciled if the inclusions are gas rich as hasd been reported for several other MVT provinces.