1. Supporting document for
The Potential Source Materials for Recurring Slope Lineae on Mars: Subsurface Hydrous Chlorides and Oxychlorine Salts (HyCOS)
Authors: Alian Wang1, Zongcheng Ling2, Y. C. Yan1, Alfred S. McEwen3, Michael T. Mellon4, Michael D. Smith5, Bradley L. Jolliff1, James Head6
Affiliations: 1Dept. Earth and Planetary Sciences and McDonnell Center for Space Sciences, Washington University in St. Louis, St. Louis, Missouri, 63130, USA;
2Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, Institute of Space Sciences, Shandong University, Weihai, , China;
3Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona, 85721, USA;
4Applied Physics Laboratory, Johns Hopkins University, Laurel, Maryland, 20723, USA
5NASA Goddard Space Flight Center, Greenbelt, Maryland, 20771, USA
6Dept. Earth, Environmental and Planetary Sciences, Brown University, Rhode Island, 02912, USA;
This document contains:
Figure S1. Stability field and phase boundaries of hydrous Mg-sulfates
Figure S2. Stability field and phase boundaries of hydrous Fe3+-sulfates
Figure S1. Stability field and phase boundaries of hydrous Fe2+-sulfates
Table S1. RHbuffer (T) of ten EH buffers used in experiment #1

2. brine
Figure S1. Stability fields and phase boundaries of hydrous Mg-sulfates 1,2,3
Notice the 7w-deliquescence boundary intersects with 273K isothermal line at about 95%RH. Am=amorphousMgSO4·xH2O (x<3), LH-1w=Low Humidity MgSO4·H2O; 4w=MgSO4·4H2O, 6w=MgSO4·6H2O, 7w=MgSO4·7H2O, LT-7w=low temperature MgSO4·7H2O , 11w=MgSO4·11H2O, deliq=deliquescence, meta=metastable.

3. brine
Figure S2. Stability fields and phase boundaries of hydrous Fe3+ -sulfates 4,5,6,7,
Notice the 20W-deliquescence boundary intersects with 273K isothermal line at about 75 %RH.
4w=FeHSO4·4H2O, 5w=Fe2(SO4)3.5H2O, 7w=Fe2(SO4)3.7H2O, p9w=paracoquimbite =Fe2(SO4)3.9H2O, 20w=Fe4.67(SO4)6(OH)2.20H2O, Am=amorphous Fe2(SO4)3.5H2O, deliq=deliquescence.

4. Chou et al.,
brine
Figure S3. Stability fields and phase boundaries of hydrous Fe2+ -sulfates 8,9
Notice the 7w-deliquescence boundary intersects with 273K isothermal line at about 96%RH. 1w=FeSO4·H2O; deliq=deliquescence.

5. Table S1. RHbuffer (T) of ten EH buffers used in experiment #1
323K
294K
278K
LiBr
5.5
6.6
7.4
LiCl
11.3
MgCl2
30.5
33.0
33.6
Mg(NO3)2
45.4
54.1
58.9
NaBr
51.5
58.8
63.5 KI
64.5
70.0
73.3
NaCl
74.4
75.4
75.7
KCl
81.2
85.0
87.7
KNO3
84.8
94.4
96.3
H2O
100
100.0
*Data from Greenspan

6. References cited in supporting document:
Wang Alian, Freeman J. F., Jolliff B. L., Chou I. M, (2006) Sulfates on Mars: a Systematic Raman Spectroscopic Study of Hydration States of Magnesium Sulfates, Geochim. Cosmochim. Acta, V70, p
Wang Alian, John J. Freeman, Bradley, L. Jolliff (2009), Phase Transition Pathways of the Hydrates of Magnesium Sulfate in the Temperature Range 50 ºC to 5 ºC: Implication for Sulfates on Mars, J. Geophys. Res., 114, doi: /2008JE
Wang Alian, J. J. Freeman, I-Ming Chou, B. L. Jolliff (2011), Stability of Mg-sulfates at -10C and the Rates of Dehydration/Rehydration Processes under Mars Relevant Conditions, J. Geophys. Res., Res., 116, E12006, doi: /2011JE
Wang Alian, Ling Z. C. Freeman J. J. (2012) Stability field and Phase Transition Pathways of Hydrous Ferric Sulfates in the Temperature Range 50 °C to 5 °C: Implication for Martian Sulfates, Icaru, 218, , doi: /j.icarus
Kong, W. G., Alian Wang, and I-M. Chou (2011), Determination of phase boundary between kornelite and pentahydrated Ferric Sulfate by humidity buffer technique and Raman spectroscopy at 0.1 Mpa. Chemical Geology, Vol 284,
Kong W. G., Alian Wang, John J. Freeman, and Pablo Sobron (2011), A Comprehensive Spectroscopic Study of Synthetic Fe2+, Fe3+, Mg2+, Al3+ Copiapite, J. Raman Spectroscopy, doi /jrs.2790.
Ling Z. C., Alian Wang (2010), A Systematic Spectroscopic Study of Eight Hydrous Ferric Sulfates Relevant to Mars, Icarus, 209, , doi:/ /j.icarus
Alian Wang and Kathryn Connor, 2014, Stability fields of hydrous ferrous sulfates and their pathways in dehydration-rehydration processes, Abs #1070 for 8th International Conference on Mars
Wang Alian, Yuhang Zhou (2014) Experimental Comparison of the Pathways and Rates of the Dehydration of Al-, Fe-, Mg-, and Ca-Sulfates under Mars Relevant Conditions, ICARUS, 234,
Chou I.M., R. R. Seal II, B. S. Hemingway, Determination of melanterite-rozenite and Chalcanthite-bonattite equilibria by humidity measurements at 0.1 Mpa, Am. Mineralogists, V87, p
Greenspan, L. Humidity fixed points of binary saturated aqueous solution. J. Res. Natl. Bureau of Standards—A. Phys. Chem. 81A (1), 89–96 (1977).