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Abstract. Tracking the evolution of the deformational energy budget within accretionary systems provides insight into the driving mechanisms that control fault development. To quantify the impact of these mechanisms on overall system efficiency, we estimate energy budget components as the first thrust fault pair develops in dry-sand accretion experiments. We track energy budget components in experiments that include and exclude a basal layer of glass beads in order to investigate the influence of detachment strength on work partitioning. We use the measurements of normal force exerted on the backwall to estimate external work, and measurements of strain observed on the sides of the sand packs to estimate the internal work, frictional work and work against gravity done within increments of each experiment. Thrust fault development reduces the incremental external work and incremental internal work, and increases the incremental frictional work and incremental gravitational work. The faults that develop within higher-friction detachment experiments produce greater frictional work than the faults in experiments with glass bead detachments because the slip distribution along the detachments remains the same, while the effective friction coefficient of the detachment differs between the experiments. The imbalance of the cumulative work budget suggests that additional deformational processes that are not fully captured in our measurements of the energy budget, such as acoustic energy, consume work within the deforming wedge.
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Digital Image Correlation data from experiments of releasing bend evolution within different strength wet kaolin
The data set includes the Digital Image Correlation (DIC) results for four experiments of releasing bends along dextral strike-slip faults that were performed at the University of Massachusetts at Amherst (USA). Gabriel et al. (in prep.) used the DIC data sets to investigate how releasing bend fault systems evolve within different strength wet kaolin. Information on the experimental set up and methods can be found in the main text and supplement to Gabriel et al. (in prep.). The data here include the incremental displacement time series, strain animation and surface elevation data at the end of the two experiments with different clay strength, which are presented within Gabriel et al. (in prep). We also include in this data repository incremental displacement time series and strain animations from two experiments that repeat the conditions of the experiments featured in Gabriel et al. (2025).
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- Award ID(s):
- 2040570
- PAR ID:
- 10608813
- Publisher / Repository:
- GFZ Data Services
- Date Published:
- Subject(s) / Keyword(s):
- strike-slip deformation releasing bend off-fault defroamtion EPOS multi-scale laboratories analogue models of geologic processes analogue modelling results Clay Cohesion depression Digital Image Correlation (DIC) / Particle Image Velocimetry (PIV) EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > CRUSTAL MOTION EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > FAULT MOVEMENT EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > STRAIN graben Matlab (Mathworks) normal fault Shear box SLR camera Structure from Motion (SfM) tectonic process > transform faulting tectonic setting > plate margin setting > transform plate boundary setting wrench fault Yield stress
- Format(s):
- Medium: X
- Right(s):
- Creative Commons Attribution 4.0 International
- Institution:
- University Of Massachusetts Amherst Geomechanics
- Sponsoring Org:
- National Science Foundation
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