11th International GeoRaman Conference (2014) 5004.pdf
Spectroscopic comparison of Lafayette & MIL 03346 vein-filling materials. K. E. Kuebler [email protected]
Introduction: The primary goal of this project is to 2004 with a few modifications made per 1, 2]. At characterize the phyllosilicate alteration products in present, the database contains > 100 phyllosilicate Lafayette (or Nakhla) using correlated Raman Raman spectra (Figs. 1, 2), most of which are supported spectroscopic and EMP traverses much like those [1, 2] by EMPA and some by IR (some samples donated by performed on ALHA 77005 and MIL 03346. These ASU [7]). We would like to collect XRD patterns, more data are compared to the MIL traverses of [1]. IR spectra (several from each major group), and append Preliminary Raman traverses were collected on the database (especially the clays). We anticipate that Lafayette by [3, data reused here] but this work is this data will lead to 2 or 3 new mineral calibrations hindered by traces of a former carbon coat and need to (e.g., biotite and chlorite – per [8, 9]); Tschermak, AlIV be recollected. and AlVI, F/OH substitutions will have to be explored. These data reflect the status of the phyllosilicate Major Raman spectral features of phyllosilicates: database initiated by the Planetary Surface Materials Wang et al. [8] discuss the major features of Research Group at Washington University during the dioctahedral and trioctahedral phyllosilicates using four development of the MMRS [4–6, originally compiled in spectral regions: < 600 cm-1, 600 – 800 cm-1, 800 – -1 -1 standard biotite and chlorite spectra 1150 cm , and 3000 – 3800 cm . Bridging oxygen -1 phlogopite peaks (Si-Ob-Si) occur in the 600 – 800 cm region,
679 3714 non-bridging oxygen peaks (Si-Onb) in the 800 – 1150 191 OH -1 -1 cm region, OH and H2O peaks in the 3000 – 3800 cm
337
283
554
782
1085
512 1037 3300 3700 region. The number of OH peaks, their positions, and relative intensities are controlled by the number and type annite
714
668 3658 of crystalographically equivalent OH groups and the 760 OH
164 cations surrounding the OH sites; e.g., N, I, V type
935
522
225
1015
888
1050
264 395 hydrogen bonds [8, 10].
355 3300 3700 Most trioctahedral phyllosilicates have strong peaks -1 lepidomelane between 180 and 250 cm , one or more strong Si-Ob-Si
3599 OH 3651 -1
751
182
716
557 peaks between 670 and 700 cm , and one or more weak
681
158
138 peaks in the Si-Onb region [8]. Lepidolite is the only
910 3300 3700
394 1092 trioctahedral phyllosilicate with a Si-Ob-Si peak position > 700 cm-1 because Li+ is so light [8, 11]. Fe3+ bearing biotite, BUR-840
721 3685 phyllosilicates have broad, multi-component peaks of OH 3660
680
769 -1
184 moderate strength near 550 cm (attr. to vibrations
143
552 VI
509
408
280 920 involving Al by [9], confirmed by the spectra in our 1086 3300 3700 database) while Mg-phyllosilicates have weak to -1 200 400 600 800 1000 1200 1400 moderate peaks between 325 and 370 cm . The character and peak positions of the Si-O -Si peaks clinochlore b OH & H O 2 3588 3682 change with cation composition [8].
204
3445
683
551 Comparison of Lafayette and MIL 03346
357
1057 alteration products: The MIL alteration products
128 472
284 3300 3700 appear smooth in thin section but those of Lafayette chamosite have a micaceous habit (Fig. 3; same thin section as that H O 3646 548 2
3563 pictured in [12]). The conversion of smooth alteration
3431
671 522 products into micaceous morphologies is apparent in the
1053
790
896
202
363
429 278 3300 3700 Lafayette sections studied by [13]. The vein-filling
chlorite, WAR 1924 alteration products of MIL were identified as
3579 H2O stilpnomelane by [1] and presumably formed at
3680
206
3440
552 681 pressures akin to that of low grade diagenesis. The
355
132 1049 Raman spectra of the Lafayette alteration products (see 3300 3700 Fig. 4) are more consistent with vermiculite [3] but 200 400 600 800 1000 1200 1400 IV -1 saponite (smectite) generally contains far less Al and Raman shift (cm ) AlVI than vermiculite, which is more consistent with our Fig. 1) Raman spectra of several trioctahedral phyllosilicate EMP data [14]. The vein-filling materials of MIL and standards. Lafayette have similar SiO2 contents but the
Abstract for 11th GeoRaman International Conference, June 15-19, 2014, St. Louis, Missouri, USA 11th International GeoRaman Conference (2014) 5004.pdf
H2O of MIL. Perhaps the vermiculite can be explained as an
554
615
188 vermiculite alteration product of the stilpnomelane. Vermiculite is
672
332 390
758
935 3300 3700
1075 usually inferred to be a weathering or hydrothermal alteration product of chlorite and biotite [15]. H2O
552 675 zonalite Acknowledgements: The WU database was 190 established by the Planetary Surface Materials Research 765 (anhydrous)
354
1080
927 430 3300 3700 Group during the development of the MMRS; use of the data acknowledged by Alian Wang. H O & OH 680 2
552 vermiculite 191 References: [1] Kuebler (2013a) JGR, 118, 347-
520
778 354 var. jeffersite
1075
908
1030 368, doi: 10.1029/2012JE004244; [2] Kuebler (2013b) 428 3300 3700
277 JGR, 118, 803-830, doi: 10.1029/2012JE004243; [3] H2O & OH
555 Kuebler et al. (2004) LPSC XXXV, Abstract #1704; [4]
354
674 DuVal
187
392
618 428 vermiculite Wang et al. (2003) JGR 108, E1, 5005, doi:
265 752
1088 905 290033003700 10.1029/2002 JE001902; [5] Kuebler et al. (2006) LPSC XXXVII, Abstract # 1907; [6] Wang et al. (2014) H2O in progress; [7] R. Ruff website: http://rruff.info/
676
547
1087 vermiculite
191
352
711
793 3300 3700 (accessed 12/20/13); [8] Wang et al. (2002) LPSC
275 XXXIII, Abstract #1374; [9] Prieto et al. (1991) Clays H2O and Clay Minerals, 39, 5, 531-539; [10] Vedder (1964)
675
187 vermiculite Am. Min., 49, 736-768; [11] Klein and Hurlbut (1985)
355
549 1054 3300 3700
431 277 Manual of Mineralogy. John Wiley & Sons, NY; [12]
825 Treiman et al (2005) Chemie der Erde, 65, 203-270; 200 400 600 800 1000 1200 1400 [13] Changela and Bridges (2010) MAPS, 45, 12, 1847- Raman shift (cm-1) 1867; [14] Deer, Howie, and Zussman (1992) An Introduction to the Rock Forming Minerals, Prentice Fig. 2) Raman spectra of several vermiculite standards. Hall, Harlow, England; [15] Calle and Suquet (1988) stilpnomelane has 10 wt % more FeO, 7 wt % less MgO, Chap. 12, RIM 19, MSA, Washington, D.C. and less than < 0.5 wt % Al2O3. The stilpnomelane in Fig. 4) Raman spectral comparison of the fine and coarse grained MIL has less Al2O3 than the Lafayette vein-filling -1 alteration in Lafayette to the vein-filling materials of MIL materials [1]. The relatively strong 550 cm peak in the 033346. fine-grained alteration of Lafayette may reflect the mobilization of Al during their conversion. Spectra of the alteration products in Lafayette The Raman peaks of the MIL stilpnomelane are fine grained alteration
555
606 3617
670 broad (because the structure is modulated) and their 518
peak positions differ slightly from our standard 392
966
318
920
187 1035 3400 3800 stilpnomelane but do not resemble dioctahedral or 1112 trioctahedral phyllosilicates. The major MIL -1 coarse alteration stilpnomelane peak is ~100 cm lower than the Si-Ob-Si 658
710
peak positions of most trioctahedral phyllosilicates and 546 -1 774
853
916
> 50 cm lower than the coarse alteration products of 963
246
309 Lafayette [1, 3]. 387 Conclusions: We hope to obtain fresh samples (never carbon coated or exposed to acetone) of Smooth alteration products in MIL 03346 Lafayette or Nakhla, study their alteration products, and stilp + olivine+ jarosite elucidate their relationship to the vein-filling materials 586
508
432
454
816
843
392 688
960
1004
302
Fig. 3A) Lafayette’s micaceous alteration products. 1128 B) The vein-filling materials in MIL03346,177 are smooth.
250 500 750 1000 1250 1500 Raman shift (cm-1)
Abstract for 11th GeoRaman International Conference, June 15-19, 2014, St. Louis, Missouri, USA