The seismically fastest chemical heterogeneity in the Earth's deep upper mantle—implications from the single-crystal thermoelastic properties of jadeite

Single‐Crystal Elasticity of Phase E at High Pressure and Temperature: Implications for the Low‐Velocity Layer Atop the 410‐km Depth

“… The anisotropy factors AV P and AV S of phase E and representative minerals in the upper mantle and the transition zone. The solid lines represent phase E (red lines, this study), olivine (black lines, Mao et al., 2015), wadsleyite (blue lines, Wang et al., 2014), hydrous wadsleyite (green lines, Zhang et al., 2018) and clinopyroxene (pink lines, Hao et al., 2020) as a function of pressure at 300 K. The red dashed lines represent the anisotropy factors of phase E along a slab geotherm that is 400 K colder than the adiabatic temperature profile (Katsura et al., 2010). The vertical gray dashed line marks the boundary between the upper mantle and the mantle transition zone.…”

“…Both AV P and AV S show a decrease with pressure and an enhancement with temperature. Due to a lack of constraints on the effect of temperature on the single‐crystal elasticity of clinopyroxene and wadsleylite, we only calculated the AV P and AV S of olivine, clinopyroxene and wadsleylite as a function of pressure at the ambient temperature using the literature single‐crystal elasticity data (Hao et al., 2020; Mao et al., 2015; Wang et al., 2014; Zhang et al., 2018) for a comparison with phase E. Majorite was not included in the comparison because it is nearly elastically isotropic at high pressures and 300 K (Murakami et al., 2008; Sanchez‐Valle et al., 2019). As seen in Figure 7, the AV P of phase E is significantly lower than that of olivine, clinopyroxene and anhydrous wadsleylite but is comparable to that of hydrous wadsleyite.…”

Low‐Velocity Structure of Subducted Oceanic Crust in the Upper Mantle: Insights From High Pressure and Temperature Elasticity Measurements of Aragonite

“…We then investigated the influence of carbonate on the velocity profiles of the subducted oceanic crust (Hao et al., 2020). As the dominant component of the subducted oceanic crust, mid‐ocean ridge basalts (MORBs) were assumed to contain up to 5 wt.% CO 2 in the form of carbonate (Dasgupta & Hirschmann, 2010).…”

High‐Pressure and High‐Temperature Single‐Crystal Elasticity of Cr‐Pyrope: Implications for the Density and Seismic Velocity of Subcontinental Lithospheric Mantle

“…To examine whether the elastic properties of Cr‐pyrope at high P and high T can be calculated using the end‐member component elastic properties, we calculated the elastic properties ( ρ , K S , G , V P , and V S ) of Prp‐Cr#12 at high P and high T using the directly measured elastic parameters (Table S4 in Supporting Information ) in this study and then compared the results to those calculated using the elastic parameters interpolated from linear mixing of end‐member elastic parameters (end‐member model; Table S5 in Supporting Information ; Angel et al., 2018; Arimoto et al., 2015; Bass, 1986, 1989; Cameron et al., 1973; Chantel et al., 2016; Dymshits et al., 2014; Faccincani et al., 2021; Fan et al., 2020; Gréaux & Yamada, 2019; Gwanmesia et al., 2014, 2006; Hao et al., 2020; Hugh‐Jones, 1997; Isaak et al., 1992; Jackson et al., 2007; Jacobsen et al., 2010; Jeanloz & Thompson, 1983; Klemme et al., 2005; Kroll et al., 2012; Li & Neuville, 2010; Ma et al., 2009; Z. Mao et al., 2015; Milani et al., 2015, 2017; Ohashi, 1984; Sang & Bass, 2014; Sinogeikin & Bass, 2000, 2002; Soga, 1967; Tribaudino et al., 2008; Wang & Ji, 2001; Xu et al., 2018, 2020, 2022; Yang & Ghose, 1994; Zhang & Bass, 2016a, 2016b; Zhang et al., 1998; Zhao et al., 1997, 1998; Zou, Gréaux, et al., 2012). We calculated the elastic properties at pressures of 3–8 GPa at 1000 and 1600 K, which are the lower and upper bound of typical SCLM P ‐ T conditions where garnet‐peridotite stabilizes.…”