Preprints
Filtering by Subject: Geophysics and Seismology
The importance of anisotropic viscosity in numerical models for olivine textures in shear and subduction deformations
Published: 2023-10-05
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Olivine lattice preferred orientation (LPO), or texture, forms in relation to deformation mechanisms such as dislocation creep and can be observed in the upper mantle as seismic anisotropy. Olivine is also mechanically anisotropic, meaning that it responds to stresses differently depending on the direction of the stress. Understanding the interplay between anisotropic viscosity (AV) and LPO, and [...]
Antarctic Geothermal Heat Flow, Crustal Conductivity and Heat Production Inferred From Seismological Data
Published: 2023-09-15
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Geothermal heat flow is a key parameter in governing ice dynamics, via its influence on basal melt and sliding, englacial rheology, and erosion. It is expected to exhibit significant lateral variability across Antarctica. Despite this, surface heat flow derived from Earth's interior remains one of the most poorly constrained parameters controlling ice-sheet evolution. To obtain a continent-wide [...]
A Cascadia Slab Model from Receiver Functions
Published: 2023-09-08
Subjects: Earth Sciences, Geophysics and Seismology
We map the characteristic signature of the subducting Juan de Fuca and Gorda plates along the entire Cascadia forearc from northern Vancouver Island, Canada to Cape Mendocino in northern California, USA, using teleseismic receiver functions. The subducting oceanic crustal complex, possibly including subcreted material, is parameterized by three horizons capable of generating mode-converted waves: [...]
Evidence of subduction, collision, and extension in northern Borneo: Constraints from receiver function
Published: 2023-09-04
Subjects: Earth Sciences, Geophysics and Seismology
Northern Borneo (Sabah) has a complex geological history, experiencing multiple episodes of subduction, magmatism, uplift, subsidence, and extension since the Mesozoic. This includes the subduction of the proto-South China Sea beneath Sabah, terminating ~21 Ma; a postulated later phase of subduction of the Celebes Sea plate, terminating ~9 Ma; extension in central Sabah ~9-10Ma; rapid emplacement [...]
High Accuracy Estimation and Validation of InSAR-derived Surface Displacements at Temperate Raised Peatlands
Published: 2023-09-04
Subjects: Geophysics and Seismology, Hydrology, Soil Science
Peatland surface motion derived from satellite-based Interferometry of Synthetic Aperture Radar (InSAR) is potentially a proxy for groundwater level variations and greenhouse gas emissions from peat soils. Ground validation of these motions at equivalent temporal resolution and accuracy has proven problematic because of limitations of traditional surveying methods. Since 2019, peat surface motion [...]
The Role of Continental Heterogeneity on the Evolution of Continental Margin Topography at Subduction Zones
Published: 2023-09-01
Subjects: Earth Sciences, Geophysics and Seismology, Other Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
The nature of the overriding plate plays a major role in shaping subduction zone processes. In particular, the highly heterogeneous continental lithosphere modulates intra-plate tectonics and the surface evolution of our planet. However, the role of continental heterogeneity is relatively under-explored for the dynamics of subduction models. We investigate the influence of rheological and density [...]
SeisMIC - an Open Source Python Toolset to Compute Velocity Changes from Ambient Seismic Noise
Published: 2023-09-01
Subjects: Computer Sciences, Earth Sciences, Environmental Monitoring, Environmental Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
We present SeisMIC, a fast, versatile, and adaptable open-source software to estimate seismic velocity changes from ambient seismic noise. SeisMIC includes a broad set of tools and functions to facilitate end-to-end processing of ambient noise data, from data retrieval and raw data analysis via spectrogram computation, over waveform coherence analysis, to post-processing of the final velocity [...]
Knowledge Graphs for Seismic Data and Metadata
Published: 2023-08-31
Subjects: Databases and Information Systems, Geophysics and Seismology
The increasing scale and diversity of seismic data, and the growing role of big data in seismology, has raised interest in methods to make data exploration more accessible. This paper presents the use of knowledge graphs (KGs) for representing seismic data and metadata to improve data exploration and analysis, focusing on usability, flexibility, and extensibility. Using constraints derived from [...]
Forecast of Earthquake Magnitude for North-West (NW) Indian Region Using Machine Learning Techniques
Published: 2023-08-24
Subjects: Geophysics and Seismology
Earthquakes have posed significant hazards to human lives and infrastructure for as far back as can be recalled. This paper presents a Machine Learning (ML) based approach for earthquake magnitude forecasting spatially using the earthquake clustering in five selected zones of NW Indian region. Previous research efforts have primarily relied on empirical relationships and statistical models, which [...]
Shear-wave attenuation anisotropy: a fluid detection tool
Published: 2023-08-24
Subjects: Geophysics and Seismology
The behaviour of fluids in preferentially aligned fractures plays an important role in a range of dynamic processes within the Earth. In the near-surface, understanding systems of fluid-filled fractures is crucial for applications such as geothermal energy production, monitoring CO2 storage sites and exploration for metalliferous sub-volcanic brines. Mantle melting is a [...]
Generation of evolving plate boundaries and toroidal flow from visco-plastic damage-rheology mantle convection and continents
Published: 2023-08-17
Subjects: Geology, Geophysics and Seismology, Tectonics and Structure
Earth's style of planetary heat transport is characterized by plate tectonics which requires rock strength to be reduced plastically in order to break an otherwise stagnant lithospheric lid, and for rocks to have a memory of past deformation to account for strain localization and the hysteresis implied by geological sutures. Here, we explore $\sim$10$^7$ Rayleigh number, visco-plastic, [...]
Pressurizing magma within heterogeneous crust: a case study at the Socorro Magma Body, New Mexico, USA
Published: 2023-08-02
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Surface deformation plays a key role in illuminating magma transport at active volcanoes, however, unambiguous separation of deep and shallow transport remains elusive. The Socorro Magma Body (SMB) lacks an upper crustal magma transport system, allowing us to link geodetic measurements with predictions of numerical models investigating rheologic heterogeneities and magma-mush interaction in the [...]
3D shear wave velocity structure in the southwestern Okinawa Trough
Published: 2023-07-28
Subjects: Geophysics and Seismology
The southwestern Okinawa Trough is an active back-arc basin, extending and rifting within the continental lithosphere. Studying the southwestern Okinawa Trough is important for understanding the processes involved in the opening and development of a back-arc basin. At various times between 2010 and 2018, the Institute of Earth Sciences, Academia Sinica, Taiwan deployed 34 Ocean Bottom [...]
Mapping Permafrost Variability and Degradation Using Seismic Surface Waves, Electrical Resistivity, and Temperature Sensing: A Case Study in Arctic Alaska
Published: 2023-07-19
Subjects: Civil Engineering, Geophysics and Seismology, Geotechnical Engineering, Hydrology
Subsurface processes significantly influence surface dynamics in permafrost regions, necessitating utilizing diverse geophysical methods to reliably constrain permafrost characteristics. This research uses multiple geophysical techniques to explore the spatial variability of permafrost in undisturbed tundra and its degradation in disturbed tundra in Utqiaġvik, Alaska. Here, we integrate multiple [...]
Transporting Heat Flux From the US and Europe to Antarctica Guided by Regional Seismic Structure
Published: 2023-07-08
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Physical Sciences and Mathematics
Subglacial geothermal heat flux affects the dynamics of the Antarctic ice sheet but is poorly known. We estimate heat flux across West Antarctica and the interior of East Antarctica by transporting heat flux observations from the contiguous US and Europe, based on seismic structure with a lateral resolution of about \qty{100}{km}. We transport with three Machine Learning models across a hierarchy [...]