Article
Computer Science, Interdisciplinary Applications
Maurizio Battaglia, Antonina Calahorrano-Di Patre, Ashton F. Flinders
Summary: gTOOLS is an open-source software for relative gravity data processing, available in MATLAB. It is designed for time-lapse gravity monitoring and allows for quick processing of gravity data with customizable outputs.
COMPUTERS & GEOSCIENCES
(2022)
Article
Environmental Sciences
Hilary Chang, Nori Nakata
Summary: Distributed acoustic sensing (DAS) has great potential for monitoring natural-resource reservoirs and borehole conditions. This study demonstrates that seismic interferometry based on deconvolution is a convenient tool for analyzing the complicated wavefield in DAS data. However, good coupling is still required to extract the signal of interest. The study also explores the applications of this technique in monitoring borehole conditions and changes in reservoir properties.
Article
Geochemistry & Geophysics
Alain Bonneville, Andrew J. Black, Jennifer L. Hare, Mark E. Kelley, Matthew Place, Neeraj Gupta
Summary: Three borehole gravity surveys were conducted in 2013, 2016, and 2018 to monitor the changes in gravity and density due to the injection and withdrawal of CO2 in the Dover 33 reef in Northern Michigan. The results showed consistent changes in CO2 mass within the reservoir over time, with increasing mass from 2013 to 2016 and decreasing mass from 2016 to 2018. By coupling time-lapse BHG results with a 3D porosity and permeability model, fluid migration within the reef was visualized and allowed for evaluating the volume of CO2 injected and the efficiency of oil sweeping.
Article
Geochemistry & Geophysics
Gang Yu, Fangjing Hu, Liangcheng Tu, Guo Zhao, Juan Chen
Summary: A micro-electro-mechanical-based 3-C borehole gravimeter with high precision has been developed in China for mineral and hydrocarbon exploration. The gravimeter consists of a three-axis gravity sensor chip based on deep silicon etching, capacitive displacement sensing, and weak signal detection circuitry. The prototype tool, which has an outer diameter of 50 mm, was tested in a borehole up to 850 m depth and showed good adaptability to the down instrument environment.
GEOPHYSICAL PROSPECTING
(2023)
Article
Geochemistry & Geophysics
Adrian Celaya, Bertrand Denel, Yen Sun, Mauricio Araya-Polo, Antony Price
Summary: This paper introduces two algorithms that can invert simulated gravity data to 3D subsurface rock/flow properties. The first algorithm is a data-driven, deep learning (DL)-based approach, while the second algorithm is also data-driven but considers the temporal evolution of surface gravity events. The target application of these algorithms is the prediction of subsurface CO2 plumes for monitoring CO2 sequestration deployments. Both algorithms outperform traditional inversion methods, producing high-resolution 3D subsurface reconstructions in near real-time. Additionally, the proposed methods achieve high scores for predicted plume geometry and data misfit, indicating the effectiveness of combining 4D surface gravity monitoring with DL techniques for monitoring CO2 storage sites.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2023)
Article
Geochemistry & Geophysics
Matheus Carlos de Souza Santos, Carlos Alberto Mendonca, Tiago de Jesus Souza, Paulo Scarano Hemsi, Otavio Coaracy Brasil Gandolfo
Summary: The determination of the depth of deep foundations using geophysical methods is a challenging problem due to the complex magnetic anomaly patterns from built structures. Common methods based on characteristic attributes of the observed field often fail to account for these complexities.
Article
Environmental Sciences
Alessandro Fedele, Renato Somma, Claudia Troise, Karen Holmberg, Giuseppe De Natale, Fabio Matano
Summary: The utility of new imaging technologies is crucial in understanding hazardous geological environments. Combining unmanned aerial vehicles (UAV) with digital photogrammetry (DP) allows geoscientists to obtain detailed spatial data for rapid mapping and analysis of dynamic processes modifying landscapes. Using the Structure from Motion (SfM) technique with repeated photogrammetric UAV surveys, researchers were able to create dense 3D point clouds and digital orthophotos for accurate remote monitoring and mapping of active volcanoes and craters.
Article
Physics, Particles & Fields
L. B. Ednaldo Junior, Manuel E. Rodrigues, Henrique A. Vieira
Summary: In this paper, the Shapiro time delay is proposed as a tool to distinguish between different black hole solutions. The analytic Shapiro time is calculated using first order expansions for four solutions: Schwarzschild, Reissner-Nordstrom, Bardeen, and Ayon-Beato and Garcia. A numerical experiment based on measurements in the solar system is conducted, which involves the outward and return paths of light passing through a black hole at the center. Different delay times of the order of 10(-4) s and 10(-6) s for a stellar black hole, and variations on the order of hours for a supermassive black hole are obtained. Considering the accuracies currently achieved in solar system measurements are on the order of 10(-12) s, it is believed that this mechanism could be used in the determination of black hole models in the near future.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Multidisciplinary Sciences
Jamie Vovrosh, Katie Wilkinson, Sam Hedges, Kieran McGovern, Farzad Hayati, Christopher Carson, Adam Selyem, Jonathan Winch, Ben Stray, Luuk Earl, Maxwell Hamerow, Georgia Wilson, Adam Seedat, Sanaz Roshanmanesh, Kai Bongs, Michael Holynski
Summary: Borehole gravity sensing has various applications and can measure features around wells, such as rock-type changes and reservoir porosity. Quantum technology gravity sensors based on atom interferometry offer faster survey speeds and reduced need for calibration. However, improvements are needed in terms of robustness and reducing size, weight, and power consumption to deploy these devices in boreholes.
Article
Engineering, Petroleum
Paulo Roberto da Motto Pires, Peter R. King
Summary: The article proposes a method to interpolate qualitative time-lapse seismic interpretations by combining the fast-marching method and the pathline-tracing algorithm. The estimated boundary positions show close agreement with the truth case at each time, making them useful for estimating water saturations in the reservoir.
Article
Physics, Multidisciplinary
E. Harikumar, Suman Kumar Panja, Vishnu Rajagopal
Summary: This paper investigates the non-commutative corrections to the maximal acceleration in DFR space-time, finding that it decreases the magnitude of the maximal acceleration. By applying the positivity condition on the maximal acceleration in commutative space-time, upper bounds on acceleration are obtained, and lower bounds on radial distances between particles under gravitational attraction in DFR space-time are derived.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Multidisciplinary Sciences
Guohao Liang, Hong Yin, Jun Allard, Fangyuan Ding
Summary: Time-lapse microscopy is crucial for studying cellular dynamics, but setting up experiments is laborious and has low output due to the cell-losing problem. To overcome this, we have designed a cost-efficient method that enables cell patterning without physical boundaries, increasing the effective-throughput of time-lapse microscopy experiments significantly.
Article
Energy & Fuels
Joonho Seon, Youngghyu Sun, Soohyun Kim, Jinyoung Kim
Summary: In this paper, a time-lapse image method is proposed to improve the classification accuracy for multistate appliances based on nonintrusive load monitoring (NILM). A log-likelihood ratio detector with a maxima algorithm was applied to construct a real-time event detection of home appliances. Simulation results confirmed that the proposed method can increase classification accuracy by up to 30% compared with conventional approaches in classifying multistate appliances.
Article
Physics, Mathematical
Stephen C. C. Anco, Jordan A. A. Fazio
Summary: In Schwarzschild spacetime, the time-like geodesic equations in coordinates adapted to the time-like hypersurface containing the geodesic have a formulation similar to that of the conserved Laplace-Runge-Lenz vector and Hamilton's vector in Newtonian gravity. The angular quantity derived from the equatorial geodesics represents the coordinate angle at which the orbit has turning points or centripetal points in the spatial equatorial plane. The temporal quantities represent the coordinate time and proper time at which these points are reached on the orbit, and they are globally constant for orbits with a single turning point, but locally constant for orbits with multiple turning points.
JOURNAL OF MATHEMATICAL PHYSICS
(2023)
Article
Astronomy & Astrophysics
Xue-Zheng Zhu, Yang Yu, Xian Gao
Summary: We investigated scalar perturbations in a spatially covariant gravity theory with a dynamical lapse function. We found that the presence of the velocity of the lapse function gives rise to two scalar degrees of freedom. By integrating out the heavy mode and deriving the effective theory for the single light field, we obtained the solution to the single mode in the form of plane waves. We calculated the corrections to the power spectrum of the light mode from the heavy mode and found a power law mode for the coupled system in large scales when the two fields are not weakly coupled.