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Appendix: Aids to the Determination of Sedimentary Carbonate Minerals

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Appendix: Aids to the Determination of Sedimentary Carbonate Minerals Appendix: Aids to the Determination of Sedimentary Carbonate Minerals 10 20 30 100 SO 60 mol % Mg or Mg C03 Fig. 54. Relationship between weight and mole percentage in magnesian calcites. Note that the graph is not a straight line, but a slightly though distinctly bent curve Appendix 197 Tables of X-ray diffraction powder data for some carbonate minerals and brucite. Table 30. X-ray powder data for simple rhombohedral carbonates (d in A) Calcite Rhodochrosite Siderite Magnesite CaC03 MnC03 FeC03 MgC03 hkil d lnt. d lnt. d lnt. d lnt. hkl (hex) (rh) olD 3.8551 12 3.6581 35 3.5903 25 3.5387 110 1014 3.0359 100 2.8440 100 2.7912 100 2.7412 100 211 0006 2.8440 3 2.6107 2.5622 2.5027 17 222 1120 2.4949 14 2.3886 20 2.3443 20 2.3165 4 101 1123 2.2848 18 2.1721 27 2.1318 27 2.1023 43 210 2022 2.0946 18 2.0000 23 1.9629 30 1.9382 12 002 0224 1.9275 5 1.8290 12 1.7952 15 1.7693 3 220 OII8 1.9127 17 1.7698 30 1.7369 35 1.7002} 34 332 1126 1.8755 17 1.7623 33 1.7296 44 1.7000 321 2151 1.6259 4 1.5559 1 1.5271 1.5088 4 201 1232 1.6042 8 1.5334 13 1.5050 19 1.4865 5 21I 1.4649 1.4377 433 lOIlo 1.5872 2 1.4063 } 4 2154 1.5253 5 1.4522 1.4253 16 1.4061 310 2028 1.5180 4 1.4220 1.3956 7 1.3706 3 422 1129 1.5096 3 1.4066 1.3805 432 1.3538 } 7 1235 1.4733 2 1.3991 1.3732 1.3537 320 0330 1.4404 5 1.3790 10 1.3535 20 1.3374 8 112 00012 1.4220 3 1.3053 <1 1.2811 1.2513 3 444 2157 1.3569 1 1.2817 1.2580 1.2383 <1 421 02210 1.3391 2 1.2488 <1 1.2256 1.2021 <1 442 1238 1.2968 2 1.2219 } 1.1992 } 1.1796 } 431 30~6 } 3 17 <1 411 0336 1.2850 1 1.2194 1.1968 1.1796 330 2240 1.2475 1 1.1943 1.1722 1.1583 <1 202 2243 1.2185 1.1642 1.1427 1.1284 <1 31I 11212 1.2354 2 1.1242 1.1010 543 1.1454 } 1 <1 1341 1.1956 1.1444 1.1232 1.1098 212 3142 1.1869 1.1353 1.1143 1.1008 « 1) 301 21510 1.1799 3 1.0861 17 532 1.1066 } 1 1.0670} 4 1344 1.1539 3 1.1011 1.0807 26 1.0669· 321 0lI14 1.1731 (3) 1.0801 1.0600 } 17 1.0362 554 2246 1.1424 1 1.0860 ? 1.0659 1.0511 420 The d-spacings are from GRAF (1961). They were calculated by GRAF from the cell dimensions quoted in Table 3. The intensities for calcite, rhodochrosite, and magnesite are reduced dif- fractometer readings determined by SWANSON et al. (1953,1957). The intensities for siderite are from SHARP,W.E., Am. Mineralogist 45,241-243 (1960). 198 Appendix Table 31. X-ray powder data for rhombohedral double carbonates (d in A) Dolomite Ankerite Norsethite CaMg(CO,), Ca(Mg, Fe)(CO,), SrMg(CO,), BaMg(CO,), hk.l d Int. d Int. d Int. d Int. hkl (hex) (rh) 00.3 5.3366 5.367 ? 5.480 6 5.590 23 111 10.1 4.0297 3 4.040 4.113 14 4.196 44 100 01.2 3.6939 5 3.704 3 3.774 16 3.858 45 110 10.4 2.8855 100 2.899 100 2.954 100 3.017 100 211 00.6 2.6683 10 2.685 3 2.740 2.795 1 222 01.5 2.5382 8 2.552 2 2.600 24 2.655 29 221 11.0 2.4039 10 2.411 3 2.453 20 2.509 29 101 11.3 2.1918 30 2.199 6 2.239 26 2.289 21 210 02.1 2.0645 5 2.067 1 2.106 16 2.154 23 111 20.2 2.0149 } 15 } 2.020 3 2.056 } 33 2.103 } 26 10.7 2.0046 2.055 2.098 FOO322 02.4 1.8470 5 1.852 1 1.887 9 1.929 7 220 01.8 1.8037 20 1.812 6 1.850 31 1.888 18 332 11.6 1.7860 } 30 6 1.827 } 42 1.867 } 22 { 321 00.9 1.7789 } 1.792 1.827 1.863 333 20.5 1.7454 - 1.751 1.784 1.823 1 311 21.1 1.5662 8 1.569 1 1.598 6 1.634 3 201 12.2 21I 1.5442 } 10 } 1.548 2 1.576 } 14 1.612 } 12 02.7 1.5396 1.575 1.609 331 10.10 1.4943 2 1.501 <1 1.533 4 1.564 3 433 21.4 1.4646 5 1.468 2 1.496 12 1.529 11 310 20.8 1.4428 4 1.449 3 1.477 8 1.508 5 422 11.9 1.4300 10 1.436 1 1.465 5 1.496 4 432 12.5 1.4124 4 1.416 <1 1.443 6 1.475 6 320 03.0 1.3879 15 1.391 1 1.416 6 1.448 4 112 01.11 1.3739 1.381 1.410 1.439 1 443 30.3 } 1.3432 1.347 1.402 { 300 03.3 1.371 } 3 221 6 00.12 1.3342 8 1.341 1 1.370 1.397 1 444 21.7 1.2965 4 1.300 <1 1.325 5 1.354 3 421 02.10 1.2691 4 1.273 <1 1.300 6 1.327 3 442 12.8 1.265 5 1.293 4 431 1.2371 } 5 } 1.241 03.6 } 1.2313 } 1.258 3 3 {41I 30.6 } 1.286 330 22.0 1.2020 3 1.205 <1 1.226 4 1.254 4 202 The d-spacings for dolomite are those calculated by GRAF (1961) from the cell dimensions of the ideally ordered mineral quoted in Table 4. The intensities given for dolomite and the data for the ankerite, Ca1.03Mgo.63Feo.33(C03b are observed values from HOWIE and BROADHURST (1958) (cf. Table 4). The d-spacings for SrMg(C03h (FROESE, 1967) and norsethite are calculated values which are based on the cell dimensions quoted in Table 4. Appendix 199 Table 32. X-ray powder data for huntite, CaMg3 (C03)4 hk.l hkl dinA lnt. hk.l hkl dinA lnt. (hex) (rh) (hex) (rh) 10.1 100 5.670 3 32.1 302 1.836 5 11.0 101 4.753 2 04.2 222 1.821 5 02.1 111 3.643 5 14.0 2lj 1.797 5 01.2 110 3.532 * 02.4 220 1.766 30 21.1 201 2.891 50 22.3 31I 1.756 31 20.2 200 2.835 100 23.2 312 1.701 6 03.0 112 2.744 4 21.4 310 1.656 * 00.3 111 2.607 20 05.1 223 1.611 * 12.2 21I 2.435 18 33.0 303 1.584 16 22.0 202 2.377 18 01.5 221 1.537 * 11.3 210 2.286 10 24.1 313 1.526 4 13.1 212 2.192 14 50.2 114 1.518 * 40.1 3IT 1.990 30 13.4 321 1.485 31.2 301 1.972 50 14.3 322 } 1.479 } 8 10.4 211 1.902 41.3 401 30.3 300 } 2 03.3 221 } 1.890 The d-spacings are from GRAF and BRADLEY (1962). They were calculated by the authors on the basis of the lattice constants quoted in Table 10. The (relative) intensities are from KINSMAN (1967) who did not observe the reflections marked by asterisk. These were noticed by GRAF and BRADLEY to be present with faint intensities. 200 Appendix Table 33. X-ray powder data for aragonite-type carbonate minerals (d in A) Aragonite Strontianite Witherite CaC03 SrC03 BaC03 hkl d Int. d Int. d Int. 110 4.212 2 4.367 14 4.56 9 020 3.984 4.207 6 4.45 4 111 3.396 100 3.535 100 3.72 100 021 3.273 52 3.450 70 3.68 53 002 2.871 4 3.014 22 3.215 15 121 2.730 9 2.859 5 3.014 012 2.700 46 2.838 20 3.025 4 102 2.596 12 2.749 3 2.489 } 33 200 2.481 2.554 23 2.656 11 031 2.409 14 2.543 2.695 112 2.372 38 2.481 34 2.628 24 130 2.341 31 2.458 40 2.590 23 022 2.328 6 2.4511 33 2.606 211 2.188 11 2.2646 5 2.367 220 2.106 23 2.1831 16 2.281 6 040 1.992 2.1035 7 2.226 2 221 1.977 65 2.0526 50 2.150 28 041 1.882 32 1.9860 26 2.104 12 202 1.877 25 1.9489 21 2.048 10 132 1.814 23 1.9053 35 2.019 21 141 1.759 4 1.8514 3 1.956 113 1.742 25 1.8253 31 1.940 15 023 1.8134 16 1.931 1.725 } 15 231 1.728 1.8023 4 1.892 222 1.698 3 1.7685 7 1.859 3 042 1.636 1.7253 5 1.830 2 310 1.618 1.6684 3 033 1.6335 } 1.737 2 } 1.553 240 1.6236 4 1.706 1 311 1.557 4 1.6080 13 1.677 5 Compiled from SWANSON et al.
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