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This repository stores data using for the manuscript: Unraveling the Connection between Subsurface Stress and Geomorphic Features The data file used in this study is 'Input_stress_fault_river_BK_091525.csv'. The code used to reproduce all figures in the manuscript is 'Kuhasubpasin_et_al_2025.ipynb' The file contain these following data: Column unit range description lat degree (-90, 90) Latitude lon degree (-180, 180) Longitude azi_R degree (0, 180)* Interpolated azimuth of river network (interpolate without considering river order) azi_r1 degree (0, 180)* Interpolated azimuth of 1'-order river azi_r2 degree (0, 180)* Interpolated azimuth of 2'-order river azi_r3 degree (0, 180)* Interpolated azimuth of 3'-order river azi_r4 degree (0, 180)* Interpolated azimuth of 4'-order river azi_r5 degree (0, 180)* Interpolated azimuth of 5'-order river Drainage_area cell - Drainage area river_order order (1, 7) Majority of the order river in grid cell elev km (0, 5.1375) Elevation TcstDens g/cm^3 (2.7439,2.962) Average crustal density from CRUST 1.0 TcstThk km (5.0731 73.517) Total crustal thickness from CRUST 1.0 crust_type     Crustal type from ECM1 Te km (1,200) Effective elastic thickness MI - (-1,1) Mantle influence index azi_Z degree (0, 180)* Topographic aspect azi_F degree (0, 180)* Interpolated azimuth of faults reg_F - (0, 1) Regime of F azi_SO degree (0, 180)* Interpolated azimuth of feature 𝜎𝑂 from WSM reg_SO - (0, 1) Regime of 𝜎𝑂 azi_SO_010 degree (0, 180)* Interpolated azimuth of 𝜎𝑂 measured between 0-10 km azi_SO_1020 degree (0, 180)* Interpolated azimuth of 𝜎𝑂 measured between 10-20 km azi_SO_2030 degree (0, 180)* Interpolated azimuth of 𝜎𝑂 measured between 20-30 km azi_SO_3040 degree (0, 180)* Interpolated azimuth of 𝜎𝑂 measured between 30-40 km azi_SO_nofm degree (0, 180)* Interpolated azimuth of 𝜎𝑂 measured from focal mechanism azi_SO_fm degree (0, 180)* Interpolated azimuth of 𝜎𝑂 measured from other techniques azi_SL degree (0, 180)* Interpolated azimuth of 𝜎𝐿 reg_SL - (0, 1) Regime of 𝜎𝐿 sp1_SL Pa - Magnitude of principal stress 1 for 𝜎𝐿 sp2_SL Pa - Magnitude of principal stress 2 for 𝜎𝐿 azi_SM degree (0, 180)* Interpolated azimuth of feature 𝜎𝑀 reg_SM - (0, 1) Regime of 𝜎𝑀 sp1_SM Pa - Magnitude of principal stress 1 for 𝜎𝑀 sp2_SM Pa - Magnitude of principal stress 2 for 𝜎𝑀 azi_ST degree (0, 180)* Interpolated azimuth of feature 𝜎𝑇 reg_ST - (0, 1) Regime of 𝜎𝑇 sp1_ST Pa - Magnitude of principal stress 1 for 𝜎𝑇 sp2_ST Pa - Magnitude of principal stress 2 for 𝜎𝑇 azi_SB degree (0, 180)* Interpolated azimuth of feature 𝜎𝐵 delta_SO_F degree (0, 90) Δ𝜎𝑂−𝐹 delta_SL_F degree (0, 90) Δ𝜎𝐿−𝐹 delta_SM_F degree (0, 90) Δ𝜎𝑀−𝐹 delta_ST_F degree (0, 90) Δ𝜎𝑇−𝐹 delta_SB_F degree (0, 90) Δ𝜎𝐵−𝐹 delta_SO_R1 degree (0, 90) Δ𝜎𝑂−𝑅1 :1' order river delta_SL_R1 degree (0, 90) Δ𝜎𝐿−𝑅1 delta_SM_R1 degree (0, 90) Δ𝜎𝑀−𝑅1 delta_ST_R1 degree (0, 90) Δ𝜎𝑇−𝑅1 delta_SB_R1 degree (0, 90) Δ𝜎𝐵−𝑅1 delta_F_R1 degree (0, 90) Δ𝐹−𝑅1 delta_SO_R2 degree (0, 90) Δ𝜎𝑂−𝑅2 :2' order river delta_SL_R2 degree (0, 90) Δ𝜎𝐿−𝑅2 delta_SM_R2 degree (0, 90) Δ𝜎𝑀−𝑅2 delta_ST_R2 degree (0, 90) Δ𝜎𝑇−𝑅2 delta_SB_R2 degree (0, 90) Δ𝜎𝐵−𝑅2 delta_F_R2 degree (0, 90) Δ𝐹−𝑅2 delta_SO_R3 degree (0, 90) Δ𝜎𝑂−𝑅3 :3' order river delta_SL_R3 degree (0, 90) Δ𝜎𝐿−𝑅3 delta_SM_R3 degree (0, 90) Δ𝜎𝑀−𝑅3 delta_ST_R3 degree (0, 90) Δ𝜎𝑇−𝑅3 delta_SB_R3 degree (0, 90) Δ𝜎𝐵−𝑅3 delta_F_R3 degree (0, 90) Δ𝐹−𝑅3 delta_SO_R4 degree (0, 90) Δ𝜎𝑂−𝑅4 :4' order river delta_SL_R4 degree (0, 90) Δ𝜎𝐿−𝑅4 delta_SM_R4 degree (0, 90) Δ𝜎𝑀−𝑅4 delta_ST_R4 degree (0, 90) Δ𝜎𝑇−𝑅4 delta_SB_R4 degree (0, 90) Δ𝜎𝐵−𝑅4 delta_F_R4 degree (0, 90) Δ𝐹−𝑅4 delta_SO_R5 degree (0, 90) Δ𝜎𝑂−𝑅5 :5' order river delta_SL_R5 degree (0, 90) Δ𝜎𝐿−𝑅5 delta_SM_R5 degree (0, 90) Δ𝜎𝑀−𝑅5 delta_ST_R5 degree (0, 90) Δ𝜎𝑇−𝑅5 delta_SB_R5 degree (0, 90) Δ𝜎𝐵−𝑅5 delta_F_R5 degree (0, 90) Δ𝐹−𝑅5 delta_SO_R>1 degree (0, 90) Δ𝜎𝑂−𝑅>1 :>1' order river delta_SL_R>1 degree (0, 90) Δ𝜎𝐿−𝑅>1 delta_SM_R>1 degree (0, 90) Δ𝜎𝑀−𝑅>1 delta_ST_R>1 degree (0, 90) Δ𝜎𝑇−𝑅>1 delta_SB_R>1 degree (0, 90) Δ𝜎𝐵−𝑅>1 delta_F_R>1 degree (0, 90) Δ𝐹−𝑅>1 delta_SO_Z degree (0, 90) Δ𝜎𝑂−𝑍 delta_SL_Z degree (0, 90) Δ𝜎𝐿−𝑍 delta_SM_Z degree (0, 90) Δ𝜎𝑀−𝑍 delta_ST_Z degree (0, 90) Δ𝜎𝑇−𝑍 delta_SB_Z degree (0, 90) Δ𝜎𝐵−𝑍 delta_F_Z degree (0, 90) Δ𝐹−𝑍 delta_Z_R1 degree (0, 90) Δ𝑍−𝑅1 :1' order river delta_Z_R2 degree (0, 90) Δ𝑍−𝑅2 :2' order river delta_Z_R3 degree (0, 90) Δ𝑍−𝑅3 :3' order river delta_Z_R4 degree (0, 90) Δ𝑍−𝑅4 :4' order river delta_Z_R5 degree (0, 90) Δ𝑍−𝑅5 :5' order river delta_Z_R>1 degree (0, 90) Δ𝑍−𝑅>1 :>1' order river *The range is not (0,360) because we only consider azimuth not direction 

Abstract Mineral phase transitions can either hinder or accelerate mantle flow. In the present day, the formation of the bridgmanite + ferropericlase assemblage from ringwoodite at 660 km depth has been found to cause weak and intermittent layering of mantle convection. However, for the higher temperatures in Earth's past, different phase transitions could have controlled mantle dynamics. We investigate the potential changes in convection style during Earth's secular cooling using a new numerical technique that reformulates the energy conservation equation in terms of specific entropy instead of temperature. This approach enables us to accurately include the latent heat effect of phase transitions for mantle temperatures different from the average geotherm, and therefore fully incorporate the thermodynamic effects of realistic phase transitions in global‐scale mantle convection modeling. We set up 2‐D models with the geodynamics softwareAspect, using thermodynamic properties computed by HeFESTo, while applying a viscosity profile constrained by the geoid and mineral physics data and a visco‐plastic rheology to reproduce plate‐like behavior and Earth‐like subduction morphologies. Our model results reveal the layering of plumes induced by the wadsleyite to garnet (majorite) + ferropericlase endothermic transition (between 450 and 590 km depth and over the 2000–2500 K temperature range). They show that this phase transition causes a large‐scale and long‐lasting temperature elevation in a depth range of 500–650 km depth if the potential temperature of the mantle is higher than 1800 K, indicating that mantle convection may have been partially layered in Earth's early history. 

Optical distortion caused by changes in the refractive index of fluid flow is a common issue in flow visualization using techniques, such as particle image velocimetry (PIV). In thermally driven convection, this distortion can severely interfere with PIV results due to the ubiquitous density and, therefore, refractive index heterogeneity in the fluid. The distortion also varies spatially and temporally, adding to the challenge. We propose a composite filter, the shadow-affected PIV region filter, which combines a series of conventional image filters to address this issue, focusing on optical distortion of thermal plumes in laminar flow. We verify the effectiveness of the filter using both synthetic particle images created from ray tracing and real particle images from the laboratory. For the first time, we effectively mitigate the optical distortion from plumes while preserving the in-plane plume velocity and overall flow pattern, with the PIV data alone. Our filter is efficient and does not require additional measurements, expensive ray tracing, or a large dataset to begin with. It can be extended to separate the flow field and the effect of optical distortion in other fluid experiments when the two components are visually distinct. Additionally, this filter can serve as a baseline algorithm for comparison when developing more advanced methods like neural networks. 

SUMMARY We expand the scope of HeFESTo by encompassing the rich physics of iron in the mantle, including the existence of multiple valence and spin states. In our previous papers, we considered iron only in its most common state in the mantle: the high-spin divalent (ferrous) cation. We now add ferric iron end-members to six phases, as well as the three phases of native iron. We also add low-spin states of ferrous and ferric iron and capture the behaviour of the high-spin to low-spin transition. Consideration of the multi-state nature of iron, unique among the major elements, leads to developments of our theory, including generalization of the chemical potential to account for the possibility of multiple distinguishable states of iron co-existing on a single crystallographic site, the effect of the high-spin to low-spin transition on seismic wave velocities in multiphase systems, and computation of oxygen fugacity. Consideration of ferric iron also motivates the addition of the chromia component to several phases, so that we now consider the set of components: Ca, Na, Fe, Mg, Al, Si, O and Cr (CNFMASO+Cr). We present the results of a new global inversion of mineral properties and compare our results to experimental observations over the entire pressure–temperature range of the mantle and over a wide range of oxygen fugacity. Applications of our method illustrate how it might be used to better understand the seismic structure, dynamics and oxygen fugacity of the mantle. 

SUMMARY We derive exact expressions for the thermal expansivity, heat capacity and bulk modulus for assemblages with arbitrarily large numbers of components and phases, including the influence of phase transformations and chemical exchange. We illustrate results in simple two-component, two-phase systems, including Mg–Fe olivine-wadsleyite and Ca–Mg clinopyroxene-orthopyroxene and for a multicompontent model of mantle composition in the form of pyrolite. For the latter we show results for the thermal expansivity and heat capacity over the entire mantle pressure–temperature regime to 40 GPa, or a depth of 1000 km. From the thermal expansivity, we derive a new expression for the phase buoyancy parameter that is valid for arbitrarily large numbers of phases and components and which is defined at every point in pressure–temperature space. Results reveal regions of the mantle where the magnitude of the phase buoyancy parameter is larger in magnitude than for those phase transitions that are most commonly included in mantle convection simulations. These regions include the wadsleyite to garnet and ferropericlase transition, which is encountered along hot isentropes (e.g. 2000 K potential temperature) in the transition zone, and the ferropericlase and stishovite to bridgmanite transition, which is encountered along cold isentropes (e.g. 1000 K potential temperature) in the shallow lower mantle. We also show the bulk modulus along a typical mantle isentrope and relate it to the Bullen inhomogeneity parameter. All results are computed with our code HeFESTo, updates and improvements to which we discuss, including the implementation of the exact expressions for the thermal expansivity, heat capacity and bulk modulus, generalization to allow for pressure dependence of non-ideal solution parameters and an improved numerical scheme for minimizing the Gibbs free energy. Finally, we present the results of a new global inversion of parameters updated to incorporate more recent results from experiment and first principles theory, as well as a new phase (nal phase), and new species: Na-majorite and the NaAlO2 end-member of ferropericlase. 

SUMMARY Phase transitions play an important role for the style of mantle convection. While observations and theory agree that a substantial fraction of subducted slabs and rising plumes can move through the whole mantle at present day conditions, this behaviour may have been different throughout Earth’s history. Higher temperatures, such as in the early Earth, cause different phase transitions to be dominant, and also reduce mantle viscosity, favouring a more layered style of convection induced by phase transitions. A period of layered mantle convection in Earth’s past would have significant implications for the secular evolution of the mantle temperature and the mixing of mantle heterogeneities. The transition from layered to whole mantle convection could lead to a period of mantle avalanches associated with a dramatic increase in magmatic activity. Consequently, it is important to accurately model the influence of phase transitions on mantle convection. However, existing numerical methods generally preclude modelling phase transitions that are only present in a particular range of pressures, temperatures or compositions, and they impose an artificial lower limit on the thickness of phase transitions. To overcome these limitations, we have developed a new numerical method that solves the energy equation for entropy instead of temperature. This technique allows for robust coupling between thermodynamic and geodynamic models and makes it possible to model realistically sharp phase transitions with a wide range of properties and dynamic effects on mantle processes. We demonstrate the utility of our method by applying it in regional and global convection models, investigating the effect of individual phase transitions in the Earth’s mantle with regard to their potential for layering flow. We find that the thickness of the phase transition has a bigger influence on the style of convection than previously thought: with all other parameters being the same, a thin phase transition can induce fully layered convection where a broad phase transition would lead to whole-mantle convection. Our application of the method to convection in the early Earth illustrates that endothermic phase transitions may have induced layering for higher mantle temperatures in the Earth’s past. 

Volcanic hotspots are thought to be fed by hot, active upwellings from the deep mantle, with excess temperatures ( T ex ) ~100° to 300°C higher than those of mid-ocean ridges. However, T ex estimates are limited in geographical coverage and often inconsistent for individual hotspots. We infer the temperature of oceanic hotspots and ridges simultaneously by converting seismic velocity to temperature. We show that while ~45% of plume-fed hotspots are hot ( T ex ≥ 155°C), ~15% are cold ( T ex ≤ 36°C) and ~40% are not hot enough to actively upwell (50°C ≤ T ex ≤ 136°C). Hot hotspots have an extremely high helium-3/helium-4 ratio and buoyancy flux, but cold hotspots do not. The latter may originate at upper mantle depths. Alternatively, the deep plumes that feed them may be entrained and cooled by small-scale convection. 

Abstract The water content in Earth's mantle today remains poorly constrained, but the bulk water storage capacity in the solid mantle can be quantified based on experimental data and may amount to a few times the modern surface ocean mass (OM). An appreciation of the mantle water storage capacity is indispensable to our understanding of how water may have cycled between the surface and mantle reservoirs and changed the volume of the oceans through time. In this study, we parameterized high pressure‐temperature experimental data on water storage capacities in major rock‐forming minerals to track the bulk water storage capacity in Earth's solid mantle as a function of temperature. We find that the mantle water storage capacity decreases as mantle potential temperature (T_p) increases, and its estimated value depends on the water storage capacity of bridgmanite in the lower mantle: 1.86–4.41 OM with a median of 2.29 OM for today (T_p = 1600 K), and 0.52–1.69 OM with a median of 0.72 OM for the early Earth's solid mantle (for aT_pthat was 300 K higher). An increase inT_pby 200–300 K results in a decrease in the mantle water storage capacity by – OM. We explored how the volume of early oceans may have controlled sea level during the early Archean (4–3.2 Ga) with some additional assumptions about early continents. We found that more voluminous surface oceans might have existed if the actual mantle water content today is > 0.3–0.8 OM and the early ArcheanT_pwas ≥1900 K.