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  • This dataset contains single scanning electron microscopy images for fruits/seeds collected between 2014 and 2020 from fourteen plant species found in Brazilian Cerrado as an indication of seed structure, morphology and size. The work was supported by NE/T004851/1 NERC-FAPESP Seedcorn Fund Collaboration Project "Fire-adapted seed traits in Cerrado species" between RHUL (UK) and UNESP (Brazil). Full details about this dataset can be found at https://doi.org/10.5285/730086fd-80cd-4f44-8b13-b6168c07c7a8

  • This dataset contains raw (clean but not interpreted) triaxial compressive strength data of tests conductive at elevated pressure and temperature as outlined in "Vannucchi, P., Clarke, A., de Montserrat, A., Ougier-Simonin, A., Aldega, L., & Morgan, J. P. (2022). A strength inversion origin for non-volcanic tremor. Nature Communications, 13(1), 2311. https://doi.org/10.1038/s41467-022-29944-8". The data is provided in a .zip folder containing the files of 5 experiments that are accompanied by a README file for introduction. Files format is Microsoft Excel Worksheet (.xlsx) and data are tabulated. Each file contains the corresponding relevant sample’s details, and each column of data is clearly labelled, units included. For each experiment, time, axial force, axial displacement, axial stress, confining displacement, confining pressure, axial strain A and B, axial average strain, circumferential extensometer, circumferential strain, volumetric strain, internal temperature, and axial delta P were recorded. Triaxial testing was undertaken using the MTS 815 servo-controlled stiff frame inside a vessel capable of a confining pressure up to 140 MPa at the Rock Mechanics and Physics Laboratory, British Geological Survey, UK. The confining cell is fitted with external heater bands and utilizing utilizes cascade control from internal and external thermocouples (accurate to ± 0.5°C). An initial axial pre-load of 2.3 kN was applied, to ensure a stable contact and alignment of the platens. The confining pressure vessel was then closed and filled with mineral oil confining fluid. The axial pre-load was maintained whilst the confining pressure was applied at 2 MPa/min to 60 or 120 MPa; these values were chosen to approximately bracket the pressures at the up-dip limit of seismic nucleation, corresponding to 2 – 4 km depth (Arroyo et al., 2014). At this point, whilst held in axial force and confining pressure control, the rig was heated at 2°C/min to 60°C to approximate the average temperature conditions at the depth of the up-dip limit of seismic nucleation (Harris and Spinelli, 2010). The samples were then left for approximately 1 hour allowing thermal equilibrium to be reached throughout the confining fluid and the samples. Once stable, axial loading was initiated in constant axial strain rate control at a rate of 5.0 x 10-6 s-1 until macroscopic failure occurred or a significant amount of post peak-stress axial strain was recorded (between 2% and 5%). We note that one test was conducted at the higher temperature of T=120°C with a result within 2.5% of the strength at T=60°C (Table 1). As this is below the expected sample-to-sample variability, no further temperature studies were conducted. The axial load, axial load actuator displacement, axial stress (s1), differential stress (Q=s1 - s3), confining pressure Pc (= s2= s3), confining pressure actuator displacement, axial strain (eax), circumferential strain (ecirc) and temperature were monitored throughout at sampling frequencies of 1s and 0.5kN. File names are: YYYY-MM-DD_LabProjectNumber_SiteName-SampleNumber

  • This dataset contains information about how seeds collected from Brazilian Cerrado plant species germinate in smoke water and control water solutions. Seeds were collected from site across the Cerrado between 2013 and 2020. Germination was assessed in laboratory experiments by placing seeds on wet filter paper with water and smoke water solutions. Two different methods were used. One used a commercially available smokewater, Regen 2000 and the other used smoke water produced from burning biomass collected in central Brazil. Germination was counted daily by observing emergence of radicle from the seed. The work was supported by NE/T004851/1 NERC-FAPESP Seedcorn Fund Collaboration Project "Fire-adapted seed traits in Cerrado species" between RHUL (UK) and UNESP (Brazil). Full details about this dataset can be found at https://doi.org/10.5285/ad4e3224-4674-47a1-ad1a-80c1c109f20c