Rheometry data on ash from Mt Meager, British Columbia, Canada. All measurements that generated these data were performed using an Anton Paar MCR302 rotational rheometer with an Anton Paar powder flow cell attached. The rotating measuring geometry is 24.16 mm in diameter and contains 20 evenly spaced depressions of 1.75 mm that extend the entire length of the measuring cylinder. The profiled nature of this geometry prevents particle slip during rotation. Shear rate sweeps were performed to characterise the rheological behaviour of our pyroclast-gas mixtures. ~50 g of sample (ash from Mt Meager, British Columbia, Canada) was loaded into the powder flow cell with the measuring geometry inserted. Then for a constant gas flux applied to the base of the powder flow cell, the measuring geometry was rotated to apply a range of shear rates starting at 0.1 s-1 ramping up to 328 s-1 with approximately 20 data points generated per decade. These shear rate sweeps were performed for monodisperse grain sizes from 500 µm to 63 µm at a range of volumetric gas flow rates. Specifically for the 500 µm sample the rheology experiments were performed at 0, 15, 30, 45, 50, 55, 60, 65, and 70 L min-1. For the 250 µm sample the rheology experiments were performed at 0, 15, 20, 25, 30, 35, and 40 L min-1. For the 125 µm sample the rheology experiments were performed at 0, 1, 2, 3, 4, 5, 7, 8, 9, and 10 L min-1. For the 63 µm sample the rheology experiments were performed at 0, 0.25, 0.5, 1, 1.5, 2, 3, 4, and 5 L min-1.

Synchrotron X-radiography (images) and diffraction data collected to measure rheology of Quartz coesite and stishovite.

Synchrotron X-radiography (images) and diffraction data collected to measure rheology of olivine and ringwoodite structured Co2SiO4.

This dataset contains high-speed video recordings and particle image velocimetry (PIV) analysis results from granular flow experiments performed on an inclined flume with a fixed rough substrate, at the University of Edinburgh. Included are the high-speed videos (.mp4), a Word document outlining the experimental details and analysis methods, and figures displaying key analytical results of vertical velocity and granular temperature profiles. The flows consist of sand particles with a volumetric mean diameter of 875 µm, propagating over a substrate of coarser sand with a mean diameter of 1063 µm. Experimental conditions include varying slope angles (34°–42°) to investigate the influence of inclination on flow dynamics. PIV was used to analyse the videos, generating vertical velocity profiles and granular temperature profiles. Lens distortion was corrected using MATLAB to ensure accurate measurements. This dataset is relevant to those interested in granular flow dynamics, natural hazard modelling (e.g., landslides, pyroclastic density currents), and granular flow industrial applications.

This data contains the results of numerical simulations described in the following two papers: Alisic L., Rhebergen S., Rudge J.F., Katz R.F., Wells G.N. Torsion of a cylinder of partially molten rock with a spherical inclusion: theory and simulation (2016) Geochem. Geophys. Geosyst.16 doi:10.1002/2015GC006061 Alisic L., Rudge J.F., Katz R.F., Wells G.N., Rhebergen S. Compaction around a rigid, circular inclusion in partially molten rock (2014) J. Geophys. Res. Solid Earth 119:5903-5920 doi:10.1002/2013JB010906

Experimental mechanical data for single crystal shear experiments. Grant abstract: In 2011, NERC began a scoping exercise to develop a research programme based around deep Earth controls on the habitable planet. The result of this exercise was for NERC to commit substantial funding to support a programme entitled "Volatiles, Geodynamics and Solid Earth Controls on the Habitable Planet". This proposal is a direct response to that call. It is widely and generally accepted that volatiles - in particular water - strongly affect the properties that control the flow of rocks and minerals (their rheological properties). Indeed, experiments on low-pressure minerals such as quartz and olivine show that even small amounts of water can weaken a mineral - allowing it to flow faster - by as much as several orders of magnitude. This effect is known as hydrolytic weakening, and has been used to explain a wide range of fundamental Earth questions - including the origin of plate tectonics and why Earth and Venus are different. The effect of water and volatiles on the properties of mantle rocks and minerals is a central component of this NERC research programme. Indeed it forms the basis for one of the three main questions posed by the UK academic community, and supported by a number of international experts during the scoping process. The question is "What are the feedbacks between volatile fluxes and mantle convection through time?" Intuitively, one expects feedbacks between volatiles and mantle convection. For instance, one might envisage a scenario whereby the more water is subducted into the lower mantle, the more the mantle should weaken, allowing faster convection, which in turn results in even more water passing into the lower mantle, and so on. Of course this is a simplification since faster convection cools the mantle, slowing convection, and also increases the amount of volatiles removed from the mantle at mid-ocean ridges. Nevertheless, one can imagine many important feedbacks, some of which have been examined via simple models. In particular these models indicate a feedback between volatiles and convection that controls the distribution of water between the oceans and the mantle, and the amount topography created by the vertical movement of the mantle (known as dynamic topography). The scientists involved in the scoping exercise recognized this as a major scientific question, and one having potentially far reaching consequences for the Earth's surface and habitability. However, as is discussed in detail in the proposal, our understanding of how mantle rocks deform as a function of water content is remarkably limited, and in fact the effect of water on the majority of mantle minerals has never been measured. The effect of water on the flow properties of most mantle minerals is simply inferred from experiments on low-pressure minerals (olivine, pyroxenes and quartz). As argued in the proposal, one cannot simply extrapolate between different minerals and rocks because different minerals may react quite differently to water. Moreover, current research is now calling into question even the experimental results on olivine, making the issue even more pressing. We propose, therefore, a comprehensive campaign to quantify the effect of water on the rheological properties of all the major mantle minerals and rocks using a combination of new experiments and multi-physics simulation. In conjunction with 3D mantle convection models, this information will allow us to understand how the feedback between volatiles and mantle convection impacts on problems of Earth habitability, such as how ocean volumes and large-scale dynamic topography vary over time. This research thus addresses the aims and ambitions of the research programme head on, and indeed, is required for the success of the entire programme.

These datasets are for samples collected from Volcan de Colima (Mexico) which is at coordinates: 19°30’46" N 103°37’02" W / 19.512727°N 103.617241°W. This volcano erupts magmas that are crystal-bearing, making those cooled volcanic rocks ideal for experimentation. And so samples were cored from blocks from that volcano and those cores were then returned to high temperatures (up to 1000 C) and then deformed under controlled stresses. These data form the central part of this publication: https://doi.org/10.1016/j.jvolgeores.2024.108198. The deformation experiments were performed at LMU (Munich, Germany). The volcano coordinates from which the samples were collected are given above. The samples were deformed in a high temperature hydraulic press equipped with acoustic emission sensors. This is the ideal device for determining the behaviour of the magmas from Volcan de Colima under the same stresses and temperatures at which they were erupted. The data give key clues as to the modes of flow behaviour of the magma in volcanoes. This work provides generalised insights into magma flow behaviour.

Rheometric data for suspensions of bubbles and/or particles in a Newtonian suspending liquid. Experimental suspensions are intended as analogues for multiphase magma and lava (containing volatile bubbles and solid crystals). The dataset comprises data collected using a Anton Paar MCR702 rheometer. A Newtonian working fluid (sugar syrup) suspends variable fraction of gas bubbles and solid particles. Data relating to suspensions of bubbles only are found in the folder Bubble_Suspensions, and data relating to suspensions of bubbles and particles are found in the folder 3Phase_Suspensions. For all suspensions, rheometric data were collected in a wide-gap concentric cylinder geometry using both rotational rheometry (flow curves) and oscillatory rheometry (frequency sweeps). Bubble fraction and particle fraction are varied systematically. In each folder a matlab script is provided which facilitates extraction and analysis of the raw data, which are held in .csv files

The data consists of a spreadsheet containing rheology data for 39 samples of syrup, containing air bubbles and/or spherical glass particles. These data were used by Truby et al. (2014) to support a model for the rheology of a three-phase suspension. Each sample was placed in the rheometer (concentric cylinder geometry), and the stress was stepped up and then down, taking a measurement of strain rate at each step. Further details of the experiments may be found in Truby et al. (2014). NERC grant is NE/K500999/1. Co-author working with a NERC grant, NE/G014426/1.

PROJECT DETAILS ONLY - NO DATA. We aim to conduct an in-depth study of the rheology and flow dynamics of foams and bubble suspensions in Newtonian liquids with gas volume fraction in the range 0 to 75% and to apply the results to the flow of vesicular magmas and lavas in various confined and unconfined geometries. We will determine shear and bulk viscosity and viscoelastic properties as a function of bubble concentration and size-distribution. Foam breakdown under shear, flow down slopes and along pipes will be investigated by experiments and numerical models. Results will be applied to magma flow along dykes and up conduits and lava flows down slopes