APPENDIX-Isotopic composition and average atom ratios (in mmol/mol) of Pennsylvanian (nonluminescent shell only) and modern brachiopod shells. Location Depth (cm)/ MS1 N2 Mg/Ca SD3 Na/Ca SD S/Ca SD d13C4 d18O4 Genera/Cycle Specimen (ä) (ä) TEXAS Crurithyris planoconvexa East Mtn. 180A F 14 15.9 8.8 12.0 2.6 17.2 6.8 2.67 -1.60 180B F 9 9.1 3.5 2.5 1.0 26.4 1.3 2.57 -1.76 180C F 9 15.9 8.8 2.0 2.6 17.2 6.8 Lower Salesville -380B F 7 7.5 1.2 0.8 1.0 21.1 1.1 3.95 -2.21 -380A F 17 6.5 1.9 1.1 1.8 23.8 2.0 3.51 -3.05 -880A F 16 8.6 2.3 9.0 1.0 17.0 1.5 4.20 -2.18 Upper Winchell 105E F 12 4.0 0.9 9.4 1.0 20.3 4.6 3.94 -2.48 45A F 9 5.1 1.5 8.2 1.1 18.6 3.6 4.03 -2.13 2B F 17 3.2 1.8 9.8 0.8 20.8 1.5 3.21 -1.40 2D F 17 4.3 2.0 10.1 1.2 18.9 1.4 Finis 900B F 6 8.7 1.7 11.3 1.9 25.3 3.3 3.67 -1.76 610A F 15 9.4 4.0 10.9 1.1 20.2 1.6 3.64 -2.61 610C F 13 6.5 3.3 10.2 0.4 19.2 2.0 470A F 12 4.7 0.5 9.7 1.1 19.7 2.1 3.98 -2.25 Necessity 60A F 22 6.0 2.5 8.7 0.9 16.3 1.8 3.74 -2.30 15A F 16 3.0 1.2 9.6 1.5 19.2 2.0 2.69 -2.10 -178A F 15 6.4 4.7 9.2 1.4 18.9 4.1 Wayland 220B F 15 4.4 1.1 10.1 0.9 22.2 1.7 4.59 -2.86 130A F 16 8.6 2.8 10.8 0.7 23.5 1.6 4.05 -2.19 50B F 15 6.7 3.2 10.7 0.8 21.1 1.7 3.84 -1.82 Composita subtilita . East Mtn. 180A P 8 1.7 1.3. 4.3 2.4 3.6 0.1 F 8 2.4 0.4 2.7 0.4 2.1 0.4 180B P 7 3.8 2.1 1.3 0.6 2.2 0.7 3.92 -1.60 180C P 9 2.1 0.7 1.7 0.3 2.4 0.3 3.88 -2.55 Lower Salesville -380B P 2 1.8 1.0 1.9 4.78 -2.24 -480A P 12 5.6 3.4 2.0 0.5 2.7 1.1 4.79 -1.95 -880C P 11 4.1 0.9 1.7 0.4 2.4 0.4 5.15 -2.07 Upper Winchell 35B P 8 3.4 2.0 2.0 0.7 2.5 1.2 5.41 -2.51 F 2 5.0 2.2 1.9 5.41 -2.51 19A P 12 2.4 1.5 1.2 0.5 1.6 0.5 4.72 -1.85 13B P 2 2.2 2.3 2.2 5.09 -2.22 4A P 6 1.9 0.9 1.7 0.5 1.9 0.9 4.41 -1.44 Finis 900C F 6 4.6 0.9 6.9 2.0 3.9 0.6 Necessity 15A P 8 5.1 1.1 1.8 0.8 3.0 1.1 4.32 -3.08 F 2 5.0 2.2 1.9 4.32 -3.08 -100B P 11 3.8 2.7 2.0 0.9 3.0 1.4 6.23 -2.55 -178B P 7 3.7 0.9 1.0 0.5 2.3 0.6 4.21 -3.16 Wayland 270A P 15 5.0 2.5 1.2 0.4 1.9 0.6 5.27 -1.74 220C P 14 3.9 3.9 1.8 1.3 2.4 0.7 5.26 -1.98 50B P 4 2.0 0.3 2.1 1.5 1.5 0.9 4.13 -1.53 F 10 1.7 0.6 4.9 1.5 3.1 0.9 4.13 -1.53 Neospirifer dunbari . Necessity -100A P 12 1.3 0.5 3.6 0.7 8.0 1.4 4.29 -2.28 F 2 5.4 6.5 8.1 4.29 -2.28 -115A P 3 6.3 3.0 8.1 1.8 8.6 2.8 3.52 -2.31 F 8 4.8 1.3 6.7 1.5 8.7 1.6 3.52 -2.31 -162B P 16 3.0 3.3 6.1 1.2 18.1 2.2 5.11 -2.77 F 2 5.4 6.5 8.1 5.11 -2.77 Wayland 270B P 10 1.9 0.8 2.9 0.8 7.2 1.3 4.19 -2.78 F 4 6.2 0.7 7.2 1.0 6.8 2.1 4.19 -2.78 270B P 10 1.5 0.7 3.7 1.9 7.5 1.6 4.19 -2.78 F 4 5.7 2.7 7.2 0.7 6.8 0.8 4.19 -2.78 170A P 11 1.6 0.3 2.4 0.5 4.4 0.5 F 5 3.8 1.1 6.9 2.1 5.4 0.2 170B P 11 1.3 0.2 2.8 0.6 3.6 0.5 F 4 2.8 1.5 5.6 1.2 4.1 0.3 Eridmatus texana Upper Winchell 85A P 16 1.9 0.7 2.6 1.0 8.1 2.2 4.04 -2.59 25B P 4 1.8 0.7 6.8 0.6 21.0 1.8 3.07 -1.84 13A P 11 2.2 0.8 7.2 1.6 18.3 3.2 3.28 -0.52 7B P 19 2.6 1.6 7.9 1.0 19.8 3.8 4.25 -2.07 Necessity 75A P 11 2.0 1.5 6.3 1.3 17.5 2.9 3.73 -1.61 60B P 15 2.3 1.2 8.1 1.1 21.9 2.4 3.25 -1.67 30A P 15 2.1 1.0 7.5 0.7 26.1 2.8 2.76 -1.33 Wayland 50B P 14 2.4 0.5 7.7 0.8 24.3 2.7 3.91 -1.66 50B P 14 1.9 0.9 8.1 1.2 23.2 2.8 3.91 -1.66 30A P 14 2.2 2.4 6.6 1.1 15.8 3.2 3.73 -1.30 0A P 13 1.3 0.4 8.3 0.9 26.6 1.6 3.79 -2.50 KANSAS/MISSOURI Crurithyris planoconvexa Swope 130A F 8 6.2 2.4 9.4 0.9 17.2 1.7 1.35 -4.80 130B F 16 6.3 2.1 7.8 2.2 12.1 1.4 2.76 -2.27 130C F 16 5.8 1.8 5.9 2.0 11.1 3.9 2.43 -2.29 Dennis 42A F 16 6.7 1.6 7.0 2.4 13.9 5.1 2.98 -1.90 Stanton 13A F 7 4.2 1.2 10.3 0.5 23.0 1.0 3.35 -2.12 13B F 16 5.4 2.0 10.5 0.6 23.4 1.8 3.21 -1.83 Composita subtilita Swope 138A P 4 2.2 1.1 0.9 0.2 1.5 0.3 2.63 -2.24 F 12 1.6 0.6 5.0 1.3 3.3 0.7 2.63 -2.24 138B P 16 0.8 0.8 0.9 0.4 1.7 0.7 4.20 -1.17 138C P 14 2.1 1.2 2.4 2.5 2.8 1.6 4.62 -1.72 F 2 1.7 2.6 2.2 4.62 -1.72 Dennis 152A P 16 2.3 2.6 2.3 2.2 2.7 1.3 4.11 -1.89 152B P 16 2.4 1.8 1.5 0.8 2.2 0.6 3.65 -2.12 152C P 9 1.3 0.6 1.7 0.4 2.2 0.3 4.14 -2.37 F 5 1.0 0.3 4.7 1.4 3.3 0.3 4.14 -2.37 Stanton 310A P 16 4.7 1.5 1.5 0.5 2.9 0.6 3.48 -1.32 310B P 11 2.4 1.6 1.4 0.4 2.3 0.6 3.32 -1.36 F 5 1.9 0.7 4.5 0.9 3.8 0.8 3.32 -1.36 310C P 3 4.2 0.0 2.2 0.2 3.5 0.3 4.66 -1.48 F 1 6.0 7.8 4.4 4.66 -1.48 Oread -5A P 16 2.6 0.8 1.3 0.4 1.9 0.7 4.43 -0.77 -5B P 16 2.7 1.6 1.4 0.6 2.0 0.6 4.82 -1.03 -5C P 16 2.4 1.3 1.3 0.8 1.9 0.8 4.51 -1.45 Neospirifer dunbari Dennis 152A P 16 2.5 1.4 5.9 1.1 15.2 1.9 2.97 -2.43 152B P 15 1.0 0.4 5.0 0.8 12.6 1.8 2.99 -2.14 152C P 13 1.5 1.1 3.3 1.4 9.1 3.4 2.79 -2.13 Stanton 310A P 16 1.9 0.6 4.0 0.6 10.1 1.3 2.77 -1.99 310B P 9 3.2 1.7 4.9 1.5 9.8 2.1 2.54 -2.03 F 7 3.8 1.4 5.4 1.9 7.9 2.1 2.54 -2.03 Oread 460A P 16 2.7 1.6 4.5 1.1 10.4 2.8 3.60 -1.86 460B P 16 2.0 0.7 5.1 1.1 12.7 2.0 3.87 -1.66 460C P 6 2.2 1.1 5.7 1.3 14.4 1.6 3.57 -2.06 F 7 4.7 4.8 7.8 2.0 15.6 2.3 3.57 -2.06 NEW MEXICO Crurithyris planoconvexa Hot Springs 1000A F 12 14.5 7.7 11.1 1.8 20.0 3.8 2.31 -3.95 Composita subtilita Hot Springs 800A P 3 0.7 0.5 2.3 0.2 2.0 0.2 2.74 -3.65 F 5 19.6 12.3 5.8 5.3 3.7 3.2 2.74 -3.65 800B P 7 3.0 4.5 3.2 2.3 2.1 0.8 1.92 -4.17 F 8 10.5 3.1 9.9 0.8 5.5 1.3 1.92 -4.17 800C P 6 3.3 1.6 2.0 0.5 2.5 1.5 4.05 -2.64 L. Jemez Springs 250A P 4 2.3 1.4 0.9 0.4 1.3 0.8 0.90 -4.38 F 10 5.3 5.6 4.4 1.1 3.9 0.9 0.90 -4.38 250B P 3 2.8 0.9 2.3 0.7 2.2 1.1 3.12 -3.80 F 3 11.7 3.2 7.3 1.9 4.7 1.0 3.12 -3.80 250C P 9 2.6 0.9 2.4 1.6 3.5 1.8 2.38 -3.87 U. Jemez Springs 100A P 16 4.1 2.6 1.5 0.6 2.8 1.0 3.79 -4.39 100B P 3 5.3 0.8 2.2 0.5 3.5 1.6 2.36 -4.78 100C P 1 3.9 1.2 2.0 2.65 -3.92 Neospirifer pattersoni Hot Springs 900A P 14 2.0 0.6 2.6 0.7 5.8 0.9 3.49 -3.28 F 2 10.6 7.3 7.3 3.49 -3.28 900B P 16 2.9 0.8 4.6 0.9 9.4 1.3 4.43 -2.64 900C P 16 2.8 1.3 3.3 0.7 8.1 2.2 3.33 -2.85 L. Jemez Springs 250A P 16 1.9 2.5 5.9 1.7 13.5 3.9 2.34 -3.58 250B P 12 2.3 0.8 6.7 1.1 12.5 1.9 2.57 -4.35 F 4 2.2 0.5 7.5 0.5 14.8 1.5 2.57 -4.35 250C P 16 1.8 0.5 3.6 1.1 8.2 1.9 2.66 -4.08 U. Jemez Springs 10A P 12 2.8 1.6 4.5 1.6 9.1 3.0 2.44 -5.26 10B P 16 2.4 0.9 4.7 2.2 7.8 2.0 3.31 -3.30 MODERN Mutsu Bay, Japan Terebratalia sp. A F 20 9.8 3.6 9.4 2.9 1.1 0.5 -0.26 -0.275 Terebratalia sp. B F 20 5.8 2.7 11.7 3.2 0.8 0.3 -1.13 -0.185 Monterey Bay, Laqueus californicus F 20 5.9 4.2 10.2 3.9 0.9 0.4 1.15 1.385 1microstructure; F, fibrous; P, prismatic 2number of analyses included in average 3standard deviation 4isotopic samples collected from areas on thin-sections (see Grossman et al., 1991, 1993) except where noted 5for isotopic analysis, the pedicle valve was cut along the axis of symmetry and one half of the shell was powdered