Phase transition and thermoelastic behavior of barite-group minerals at high-pressure and high-temperature conditions
- 11 Downloads
Experimental studies on the phase transition and thermoelastic behavior of barite-group minerals are crucial to understand the recycle of sulfur in Earth’s interior. Here, we present a high-pressure and high-temperature (high P–T) study on two barite-group minerals—barite (BaSO4) and celestite (SrSO4) up to ~ 59.5 GPa 700 K and ~ 22.2 GPa, 700 K, respectively, using in situ synchrotron-based X-ray diffraction (XRD) combined with diamond anvil cells (DACs). Our results show that BaSO4 undergoes a pressure-induced phase transition from Pbnm to P212121 at ~ 20.3 GPa, which is different from the previous results. Upon decompression, the high-pressure phase of BaSO4 transforms back into its initial structure, which indicates a reversible phase transition. However, no phase transitions have been detected in SrSO4 over the experimental P–T range. In addition, fitting a third-order Birch–Murnaghan equation of state to the pressure–volume data yields the bulk moduli and their pressure derivatives of BaSO4 and SrSO4. Simultaneously, the thermal expansion coefficients of BaSO4 and SrSO4 are also obtained, by fitting the temperature-volume data to the Fei-type thermal equation of state. Furthermore, the compositional effects on the phase transformation and thermoelastic behavior of barite-group minerals are also discussed, and the results suggest that the bond length of < M–O > (M=Ba, Sr, Pb) is an important factor that causes the phase transition pressure of SrSO4 to be the largest, PbSO4 is the second, and BaSO4 is the lowest.
KeywordsSulfate High temperature and high pressure Synchrotron X-ray diffraction Equation of state Diamond anvil cell
We are grateful to the beamline scientist of BL15U1 of SSRF and 4W2 of BSRF for the technical help. We also acknowledge HYS for the Neon gas-loading assistance. This project was supported by the National Natural Science Foundation of China (Grant nos. 41772043 and 41802043), the Joint Research Fund in Huge Scientific Equipment (U1632112) under cooperative agreement between NSFC and CAS, the Chinese Academy of Sciences “Light of West China” Program (Dawei Fan, 2017), Youth Innovation Promotion Association CAS (Dawei Fan, 2018434), and the CPSF-CAS Joint Foundation for Excellent Postdoctoral Fellows (Grant no. 2017LH014). The high-pressure XRD experiments were performed at the High-Pressure Experiment Station (4W2), Beijing Synchrotron Radiation Facility (BSRF), and the BL15U1 of the Shanghai Synchrotron Radiation Facility (SSRF).
- Fan D, Ma M, Wei S et al (2013) In-situ synchrotron powder X-ray diffraction study of vanadinite at room temperature and high pressure. High Temp High Press 42:441–449Google Scholar
- Fan D, Xu J, Liu J et al (2014) Thermal equation of state of natural stibnite up to 25.7. High Temp High Press 43:351–359Google Scholar
- Fei Y (1995) Thermal expansion. In: Ahrens TJ (ed) Mineral physics & crystallography: a handbook of physical constants. American Geophysical Union, Washington, DC, pp 29–44Google Scholar
- Kuang Y, Kuang J, Zhao D et al (2017) The high-pressure elastic properties of celestine and the high pressure behavior of barite-type sulphates. High Temp High Press 46:481–495Google Scholar
- Larson AC, Von Dreele RB (2004) General structure analysis system (GSAS). Los Alamos Natl Lab LAUR 86–748:1–179Google Scholar
- Miyake M, Minato I, Morikawa H, Iwai S (1978) Crystal structures and sulphate force constants of barite, celestite, and anglesite. Am Miner 63:506–510Google Scholar
- Mungall JE (2002) Roasting the mantle: Slab melting and the genesis of major Au and Au-rich Cu deposits. Geology 30:915. https://doi.org/10.1130/0091-7613(2002)030%3C0915:RTMSMA%3E2.0.CO;2 CrossRefGoogle Scholar