Table 1 Bulk (trisilver phosphate) δ18Ophos data from the Comley Limestones and SSTs exploring the influence of different values for δ18Osw.

Temperatures calculated from Eq. 1 (22). T1 δ18Osw = −6.5‰, the most reasonable value; T2 δ18Osw = −6‰, assumes no latitudinal P-E effects; T3 δ18Osw = −1‰, the most commonly used Paleozoic value; T4 δ18Osw = −8‰, incorporating the maximum likely latitudinal P-E effect of −2‰. Temperature uncertainty (2 SD T1) calculated from δ18O measurement SDs, assuming that δ18Osw = −6.5‰. See data S1.

SampleTriplicate mean δ18Ophos (‰ VSMOW)Triplicate 1 SD (‰ VSMOW)T1 (°C)T2 (°C)T3 (°C)T4 (°C)2 SD T1 (°C)
Pristine brachiopods
Aa-Br-L15.170.18202245131.6
Ad-Br-L15.060.03202345140.3
La2-Br-L13.930.22252850192.0
Lb-Br-L14.630.14222547161.3
Sa-Br-L14.620.15222547161.3
Pristine Torellella
Lb-To-To14.700.14222447151.3
Sa-To-To14.590.07222547160.6
Altered brachiopods
La2-Br-D13.330.17283053211.5
Lb-Br-D14.310.23242649172.1
Sa-Br-D13.940.18252850191.7
Sedimentary phosphate
HG-A13.950.05252850190.5
HG-A-DC14.070.21252750181.9
HG-B12.770.09313355240.8
HG-B-DC12.780.20313355241.8