geophysics

Ground subsidence in abandoned gypsum mines represents a typical geological hazard in evaporite regions, posing a direct threat to infrastructure and public safety. This study investigates a collapse-induced seismic event (ML3.4) that occurred on 8 March 2025, in an abandoned gypsum mine in Hunan Province, China. The primary objective is to propose a multi-scale conceptual model for this stratal …

Scientific Reports, Published online: 15 August 2026; doi:10.1038/s41598-026-66657-0 Statistical analysis to investigate the characteristics of Sq and SFE current using the Kakioka magnetometer

TGS and Geophysical Technology Inc. (GTI), a global provider of seismic recording technology and services, have announced a strategic collaboration agreement to jointly pursue seismic acquisition projects spanning shallow water, transition zone…

Recently, a government minister in the Northern Territory, pitching a plan to make Darwin “the data center capital of the globe,” suggested it might be a good idea to pump out groundwater to keep Earth’s spin steady. If we don’t, she said, we might risk “flipping the poles again.” Is she right? And what’s she […] The post Can pumping groundwater really flip Earth’s poles appeared first on Knowrid…

The firn layer in the upper part of the Antarctic ice sheet represents a crucial transitional zone during the transformation from snow to glacial ice, and its structural characteristics play an essential role in evaluating the surface mass balance of the ice sheet. Surface-wave inversion offers strong constraints on shallow subsurface stratification, and compared with conventional ambient noise, …

In this thread, I propose a very naive, homemade model of particle behavior in an atmosphere. Assume that the Earth and its atmosphere rotate as a unified rigid body about a fixed axis with constant angular velocity ##\boldsymbol\omega##. Assume that a particle of mass ##m## moves in a plane... Read more

Triaxial magnetometers are a critical tool used to determine how mass, momentum, and energy are coupled through near-Earth space by various geophysical phenomena. These magnetic field sensors can be deployed on spacecraft orbiting the Earth or other planetary bodies, on suborbital sounding rockets that rapidly traverse through active aurora, or at remote ground stations built to withstand adverse…

Nature Communications, Published online: 30 June 2026; doi:10.1038/s41467-026-74092-y This study introduces HARPA, a high-rate seismic phase association framework based on an optimal-transport metric. It jointly estimates earthquake parameters and wave-speed structure from dense, overlapping arrivals and opens a path to passive-source seismic tomography.

Conventional rock-physics models often neglect the coupled effects of kerogen morphology and pore geometry on elastic-wave propagation when estimating shear-wave velocity in organic-rich rocks. To address this limitation, this study proposes a shear-wave velocity prediction method that integrates the Kuster–Toksöz model with a particle swarm optimization (PSO) algorithm. In this framework, organi…

Accurate subsurface characterization is essential for geotechnical design and infrastructure development. This study integrates ERT, Seismic Refraction, and MASW to improve the assessment of foundation materials and reduce uncertainty associated with subsurface heterogeneity.

Laterolog (DLL) logging, utilizing deep and shallow detection depths, is instrumental in identifying and evaluating complex reservoirs such as coal measures. It effectively captures the resistivity contrast between the virgin zone and the invaded zone, providing crucial data for fluid identification, reservoir quality assessment, and fracture system characterization. However, the DLL response in …

The long-offset transient electromagnetic method (LOTEM) offers a large depth of investigation and high sensitivity to subsurface resistivity variations, making it valuable for deep resource exploration, oil and gas prospecting, and engineering investigations. As exploration targets move to greater depths, increasingly undulating surface and subsurface interfaces and more complex structural setti…

Our planet's liquid iron outer core is slowly giving up its secrets to a trio of satellites launched by ESA in 2013. Called Swarm, the three probes have been studying Earth's magnetic field at the source. In the process, they've revealed startling changes in a molten layer region 2,200 kilometers beneath the Pacific Ocean. In 2010, material in that area of Earth's outer core changed direction. In…

Installation of a USMTArray site in southern California in 2019. A central data logger (pictured) records electric and magnetic field variations at each site. Field personnel monitor initial data prior to leaving an instrument to record unattended for about 3 weeks. Credit: Kristin Pratscher

Quantinuum has entered into a scaled technical project with multinational integrated energy firm bp to develop quantum-hybrid algorithms for subsurface seismic imaging. The project transitions from a successful feasibility pilot into a production-oriented scaling phase designed to model more complex geophysical wave physics properties. The industrial application targets computational bottlenecks …

Accurate characterization of salt caverns is a prerequisite for evaluating the feasibility of Compressed Air Energy Storage (CAES), yet high-noise urban environments pose challenges for conventional active-source geophysical methods. To address this, our study utilized Microtremor Array Measurements (MAMs) based on the Spatial Autocorrelation (SPAC) method to characterize deep salt caverns for a …

A simple and accurate model for attenuation and dispersion caused by squirt flow in isotropic porous rocks Alkhimenkov, Yury; Quintal, Beatriz Seismic waves propagating in fluid-saturated porous rocks exhibit attenuation and velocity dispersion in a broad range of frequencies. At sonic and ultrasonic frequencies, the attenuation is predominantly caused by fluid flow in cracks and grain contacts, …

Astronomical cycles have long been proposed as potential modulators of seismicity, yet their influence remains controversial due to inconsistent results and methodological limitations. In this study it was tested whether the 18.6-year lunar nodal cycle, expressed in Earth rotation through length-of-day (LOD) variations, is detectable in global seismicity using independent earthquake catalogs (ISC…

Receiver grouping strategies for hybrid geometric-mean reverse time migration Bai, Tong; Lyu, Bin; Williamson, Paul; Nakata, Nori Geometric-mean reverse time migration (GmRTM), a powerful crosscorrelation-based imaging method, generates higher resolution source images and is more robust to noise compared with conventional time-reversal imaging. The price to pay is the higher computational costs. …

Shallow covered karst collapse is a prevalent geological hazard in Fuchuan County, Guangxi, China, posing severe threats to local engineering construction and human safety. To accurately identify subsurface karst structures and delineate collapse hazard zones, high-density electrical resistivity tomography (ERT) with Wenner, Schlumberger, and their combined array configurations was applied in a t…