Tectonic Motions Research Articles

Multidisciplinarity in Geoscientific Research

The multidisciplinary approach of geoscientific research in the academic setting underscores the increasing necessity of integrating diverse fields of knowledge to tackle complex interconnected issues. This multidisciplinary field seeks to uncover the complex operations of the Earth, encompassing the analysis of its past movements of tectonic plates, historical climates, and valuable natural resources like minerals and hydrocarbons. In this context, geospatial intelligence plays a crucial role by enabling the effective analysis and interpretation of extensive geographic datasets, thus enhancing our understanding of environmental dynamics. Nevertheless, advancements in technology, globalization, and the difficulties posed by environmental and climatic transformations demand an even more profound collaboration among various disciplines, facilitating an expansive viewpoint and yielding more holistic solutions to contemporary predicaments.

Relocation of earthquake clusters show seismogenic transverse structures in the Inner Northern Apennines (Italy)

The Inner Northern Apennines (Italy) are a region with a dominant N-S to NNW-SSE fault system, but dissected and offset by several E-W to NE-SW trending structures and lineaments. The knowledge about the nature of these transverse structures, their origin, activity and role in current tectonic motions is limited and debated. To better establish the location, subsurface shape, and kinematics of faults related to the Livorno-Empoli lineament, one of the major transverse structures in the Northern Apennines, we analysed the seismicity in western Tuscany. In the Viareggio Basin we identified and relocated two distinct earthquake clusters as well as calculated 12 new focal mechanisms. The results show that the clusters consisted of several swarms from the years 2006, 2015, 2016 and 2021. The events had a depth between 2 and 15 km and were located along a NE-SW oriented, SE dipping fault system dissecting the Viareggio Basin. Focal mechanisms show oblique normal slip. We interpret the fault system to form a connection between the Viareggio Basin and the Lucca Basin to the east as well as continuing offshore. The results show that the transversal faults of the Inner Northern Apennines are seismogenic, with the length, position and onshore to offshore nature of the fault suggesting reactivation of pre-existing structures.

GCMEbox: A MATLAB toolbox for extracting and analyzing common-mode errors from GNSS time series

High-precision global navigation satellite system (GNSS) time series data contain rich tectonic and non-tectonic motion information. However, such data also have common-mode errors (CME) related to spatiotemporal characteristics. CME will produce bias in accurate and reliable GNSS station positions and velocities estimations, ultimately deciphering erroneous geophysical signals. Currently, CME extraction methods can be divided into three categories: regional stack filtering, reference frame filtering, and statistical signal decomposition. The third method is widely used in geodetic data processing, including GNSS time series analysis, global time-varying gravity signal extraction, interferometric synthetic aperture radar (InSAR) time series analysis, etc. The demand for GNSS time series analysis software with interactive, visualization, and multifunctional features has also increased with the increase in GNSS stations. Therefore, we developed gCMEbox based on MATLAB. The gCMEbox’s primary functions include GNSS time series preprocessing, multiple statistical signal decomposition algorithms for extracting CME, GNSS time series analysis, visualization, velocity field construction, and generation of multiple time series post-processing products. Based on GNSS time series data, this study utilized the gCMEbox for data preprocessing, including format conversion, outlier removal, missing data recovery, etc. By applying statistical signal decomposition methods, gCMEbox successfully extracted CME. The primary objective of this study is to share this toolbox with the scientific community, providing a comprehensive tool for GNSS time series analysis and applications.

Active deformation in the central section of the East African Rift from tectonic, volcanic, and hydrologic processes: Observations from satellite geodesy

The East African Rift System (EARS) is an active continental rift zone that hosts a diverse range of processes that result in recent and ongoing crustal deformation. To analyze these processes, we used Sentinel-1 Interferometric Synthetic Aperture Radar (InSAR) to complement the sparse GNSS velocity field with high resolution measurements of line-of-sight (LOS) deformation between 2015 and 2022. A broad survey approach was employed to detect new signals within the central section of the EARS, and to establish a baseline for future studies focused on tectonic, volcanic, and/or hydrologic deformation and change spanning geodetic time scales. With this regional approach, we were able to resolve signals varying over time-spans of a few weeks to several years that have magnitudes greater than ∼1 cm/yr. Our resulting deformation field shows a diverse range of signals related to the processes listed above as well as other unknown sources. This includes up to 8.5 cm/yr of groundwater-related subsidence in Nairobi, up to 70 cm of LOS displacement during the eruption of Nyiragongo in 2021, and steady uplift in the Manyara basin with a rate of 2.8 cm/yr. We update previously published InSAR measurements of Mount Suswa volcano, and the geothermal fields in Olkaria. We also show LOS change ranging between 2 and 5 mm/yr over a distances of approximately 200 km spanning the Kenya Rift with the greatest differential rates occurring south of Lake Turkana. More generally, our results highlight the ambiguity of relying solely on the sparse network of GNSS for studies such as those characterizing tectonic motion and rift opening. Such studies are likely missing many important signals and/or includes sites that are contaminated with signals unrelated to the target process.

Using the Contrast Boundary Concentration of LST for the Earthquake Approach Assessment in Turkey, 6–8 February 2023

Land surface temperature (LST) variations and anomalies associated with tectonic plate movements have been documented before large earthquakes. In this work, we propose that spatially extended and dynamic linear zones of high temperature anomalies at the Earth’s surface coinciding with faults in the Earth’s crust may be used as a predictor of an approaching earthquake. LST contrast boundary concentration maps are suggested to be a possible indicator for analyzing temperature changes before and after seismic sequences. Here, we analyze the concentration of LST contrast boundaries estimated from Landsat 8–9 data for the East Anatolian Fault Zone in the vicinity of epicenters of the destructive earthquakes with magnitudes up to 7.8 Mw that occurred in February 2023. A spatial relationship between earthquake epicenters and the maximum concentration of LST boundaries at azimuths of 0° and 90° was found to strengthen as the earthquake approaches and weaken after it. It was found that 92% of epicenters are located at up to 5 km distance from zones of maximum LST boundary concentration. The evidence presented in this work supports the idea that LST may provide valuable information for seismic hazard assessment before large earthquakes.

Impact of the 2008 MW\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$M_W$$\\end{document} 7.9 Great Wenchuan earthquake on South China microplate motion

Tectonic plate motions drive the earthquake cycle, as they result in the slow accrual and sudden release of energy along plate boundaries. Steadiness of plate motions over the earthquake cycle is a central tenet of the plate tectonics theory and has long been a main pillar in models of earthquake genesis, or of plate-margins seismic potential inferred from slip-deficit estimates. The advent of geodesy in the geosciences and the availability of multi-year-long series of position measurements permit tracking the motions of tectonic plates from before to after the time of significant seismic events that occur along their margins. Here, we present evidence that large earthquakes are capable of modifying the motions of entire microplates. We use high precision Global Navigation Satellite System (GNSS) position time-series covering the periods 2001–2004 and 2014–2017 to demonstrate that, contrary to the tenet above, the South China microplate motion changed after the 2008 MW\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$M_W$$\\end{document} 7.9 Great Wenchuan earthquake. The GNSS data and associated uncertainties indicate a plate motion slowdown of up to 20% that is beyond the possible impact of data noise and is thus tectonically meaningful. We use quantitative models of torque balance to show that generating this kinematic change requires a force upon the South China microplate compatible with that imparted by the Great Wenchuan earthquake of 2008. The existence of a kinematic signal linked to the earthquake cycle that impacts an entire microplate might offer an additional, novel perspective to assessing the hazards of earthquake-prone tectonic regions.

Probabilistic Seismic Hazard Assessment of Sitamarhi near the Central Himalayan Region

ABSTRACT Sitamarhi, situated in the North-Bihar region of the Himalayan foothills is one of the seismically vulnerable regions of India. This region faced several devastating earthquakes, such as the 1934 and 1988 Bihar Nepal earthquake and the 2015 Nepal earthquake due to the movement of tectonic plates. The purpose of the present study is to exhibit the uniform hazard spectrum (UHS) and peak ground acceleration (PGA) values based on the probabilistic seismic hazard method using different seismotectonic parameters. The Gutenberg Richter (G-R) seismicity parameters ‘a’ and ‘b’ were estimated on the basis of regional earthquake magnitude data for the studied region. Regional earthquakes data were taken from the United States Geological Survey (USGS), International Seismological Centre (ISC), Indian Meteorological Department (IMD), and Seismotectonic Atlas of India. The region of interest for the probabilistic seismic hazard analysis (PSHA) is within a 500 km radius considering past seismicity and 62 seismotectonic sources which were identified in the study area. Large-scale geological features were utilised to describe the regional seismic source zones, which were used to derive the relationship between return period and ground motion parameters. Estimated PGA values are 0.92g for 2% and 0.68g for 10% probability of exceedance in 50 years time period, respectively. This research infer that the West Patna fault (WPF) and Sitamarhi fault (SMF) are the two maximum contributors in PGA for the Sitamarhi region.

Miocene sequences and depocentres in the Roer Valley Rift System

AbstractThe Miocene sequence in the Roer Valley Rift System consists of alternating open‐to‐shallow marine, coastal and fluvio‐deltaic deposits. In this study, well logs, bio‐chronostratigraphy and seismostratigraphy are used to characterize major units and their bounding unconformities and to infer sediment dispersal patterns. Three major unconformities occur in the sequence: the early, middle and late Miocene unconformities (EMU, MMU and LMU). The EMU formed due to tectonic motions related to the Savian phase. After formation of the EMU, a broad depocentre developed in the south‐eastern part of the Roer Valley Graben (RVG). Sediment accumulation increased during this period and peaked in the middle Langhian, after which it diminished again to a low level during the late Serravallian. The decrease in sediment accumulation coincided with a period of tectonic subsidence along the major bounding fault zones (i.e. the Peel Boundary Fault System, the Feldbiss Fault System and the Veldhoven Fault System). The resulting transgression caused sediment starvation in the central RVG. Subsequently, global sea‐level fall during the early Tortonian caused large‐scale erosion, and formation of incised valleys on the highs adjacent to the RVG (Peel Block and Campine Block), as well as the south‐eastern RVG, forming the MMU. However, sedimentation continued during this period in the central part of the RVG where no erosional hiatus developed. From the Tortonian onwards, accumulation rates increased again. The depocentre shifted towards the north‐west and clinoforms developed in the RVG. During the latest Miocene, the depocentre was concentrated along the south‐western margin of the RVG. Meanwhile, the depositional environment of the entire RVRS gradually shallowed as the LMU was formed.

Intraplate deformation during Gondwana breakup: a study of the Jurassic units of the Cañadón Asfalto Basin (extra-Andean Patagonia, Argentina)

SUMMARY In this study, we present the results of palaeomagnetic research conducted on Jurassic units of the Cañadón Asfalto Basin (CAB) in Patagonia, formed during Gondwana breakup. This basin is a key locality for understanding intraplate deformation within Patagonia during the Jurassic. The nature of this basin has been a subject of debate, based on the dynamics of the blocks that constitute its depocentres. In this context, the palaeomagnetic study of the Jurassic units of this basin provides a unique methodology to characterize the tectonic motions of its crustal blocks during its formation and development. To achieve this, we collected 350 samples from 53 sites in the sedimentary units of Las Leoneras (ca. 189 Ma) and Cañadón Calcáreo Formations (ca. 160–157 Ma), as well as the volcanic Lonco Trapial Group (ca. 185–172 Ma). The palaeomagnetic results from the sedimentary units show a regional remagnetization due to hydrothermal activity that obliterated the original remanence and overprinted a new one, simultaneously imprinting a secondary remanence in the volcanic units of the Lonco Trapial Group. When comparing the direction of the palaeomagnetic pole obtained from the remagnetized units with respect to average poles of equivalent ages, it is observed that the remagnetization must have occurred during the Late Jurassic (ca. 145 Ma). The age range in which this process occurred (Oxfordian to Aptian) and the direction of the calculated pole dispute a monster polar shift postulated for Late Jurassic to Early Cretaceous times. In addition, the primary magnetization recorded in the units of the Lonco Trapial Group indicates a counterclockwise rotation of the studied crustal blocks between 21° and 11°, which, in line with previous studies, refutes large-scale dextral motion along the Gastre Fault System since the Jurassic. Similar counterclockwise rotations of equivalent magnitudes are found along the units overlying the Palaeozoic Central Patagonian Igneous–Metamorphic Belt, which represents the opposite shear sense compared to the Jurassic units beyond this belt. This is interpreted as a reactivation of the Palaeozoic belt structures in the opposite sense, from transpressive during the Palaeozoic to transtensive during the Mesozoic.

The Largest Geodetic Coseismic Assessment of the 2020 Mw = 6.4 Petrinja Earthquake

On 28 December 2020, the area of the city of Petrinja was hit by two strong earthquakes of magnitudes 5.0 and 4.7 on the Richter scale, and the following day, 29 December 2020, the same area was hit by an even stronger earthquake of magnitude 6.2. It was one of the two strongest instrumentally recorded earthquakes that hit the territory of the Republic of Croatia in the last hundred years, and the strongest earthquake in the Banovina area after the great earthquake in 1909. Increased seismic activity in this area is caused by two vertical strike–slip faults, Pokupski and Petrinjski. This article aims to determine the displacements of the Earth’s crust caused by seismic activity in this area using GNSS measurements and InSAR techniques and comparing their results. Our study showed that horizontal coseismic displacements of 20 cm and more were limited to a radius of 20 km from the epicenter, with a maximum displacement of around half a meter. Considering the original plate tectonic movements of the region and the time elapsed since the previous earthquake of similar magnitude, the geodynamic movements of the Dinarides area are in substantial part sudden displacements associated with earthquakes.

Slow Slip as an Indicator of Fault Stress Criticality

AbstractFault regions inferred to be slowly slipping are interpreted to accommodate much of tectonic plate motion aseismically and potentially serve as barriers to earthquake rupture. Here, we build on prior work using simulations of earthquake sequences with enhanced dynamic fault weakening to show how fault regions that exhibit decades of steady creep or transient slow‐slip events can be driven to dynamically fail by incoming earthquake ruptures. Following substantial earthquake slip, such regions can be under‐stressed and locked for centuries prior to slowly slipping again. Our simulations illustrate that slow fault slip indicates that a region is sufficiently loaded to be failing about its quasi‐static strength. Hence, if a fault region is susceptible to failing dynamically, then observations of slow slip could serve as an indication that the region is critically stressed and ready to fail in a future earthquake, posing a qualitatively different interpretation of slow slip for seismic hazard.

Study of Asia-Pacific Plate Tectonic Motion by Using VLBI Observation

Study of Asia-Pacific Plate Tectonic Motion by Using VLBI Observation

Finding Earthquake Patterns with Time Series and Regression Models

Due to their unpredictability, earthquakes are certainly the most dangerous natural disasters. Scientists have long struggled to understand the movement of tectonic plates, as they occur at depths that cannot be directly seen and occur extremely slowly, at a rate that results in possibly one every thousand years between two adjacent plates. What if we could take a different approach, however? What if we could leverage the recent advances in machine learning to close this gap? That is exactly what we aimed to do in our research, with the question of whether various factors related to earthquakes, such as their magnitude and time of occurrence, could be determined through the analysis of years of historical data. This was conducted through the analysis of a dataset which contained records of all major earthquakes (magnitude 5.5 or higher) from 1900-2023. The library scikit-learn was used for various regression models, such as linear regression, random forest regression, and lasso regression, and the library FB prophet was used for time series forecasting, a method used to analyze patterns in previous earthquakes to predict new ones. Our conclusions were that, with some degree of error, the magnitude of an earthquake can be determined based on location/time and the time of occurrence can be pinpointed to specific days of the week as well as months.

Stability of Northern Eurasia Based on Satellite Geodesy Data

The geodynamics of Northern Eurasia has been analyzed based on repeated satellite positioning with GNSS stations throughout the Russian Federation territory from 2015 to the present. The study utilized two sources of data: observations from the stations of the Russian Fundamental Astro-Geodetic Network (FAGN) and stations of the International GNSS Service (IGS) with permanent satellite tracking. This data set allowed to estimate correctness of the block kinematics of the Eurasian plate in three tectonic plate motion models: NUVEL-1A, NNR-MORVEL-56, and ITRF2014. The analysis of the misfits between the observed and model velocities has shown that these misfits have a systematic component in the vicinity of the East European Platform which differs for each of three models. In addition to analyzing the block kinematics of the Eurasian plate, we also evaluated its internal stability. To do this, we calculated the areal deformations of Northern Eurasia using the finite element method. For this purpose, we added the observations processing results from the global data set of the Nevada Geodetic Laboratory to the processing results from two original data sets. Besides interplate boundary deformations which are consistent with existing ideas of the geodynamics of Northern Eurasia, the strain field analysis also revealed intraplate deformations distributed consistently with the configuration of the Northern Eurasia cratons.

Partial melt in mesoscale upper mantle upwellings beneath ocean basins

How tectonic plate motions are coupled with mantle flows remains an open question. Quasi-periodic 2000 km wavelength undulations aligned with absolute plate motion in the Pacific and Indian Ocean basins, observed in gravity and seafloor topography and coinciding with seismically imaged low shear velocity fingers in the upper mantle, suggest the presence of meso‑scale convection below the lithosphere. However, the correspondence of sub-lithospheric mantle mass excess, seafloor lows and slow upper mantle seismic velocities cannot be explained by temperature variations alone. Here we introduce a simplified system of bi-dimensional convective cells of width ∼1000 km, extending from the base of the lithosphere through the extended mantle transition zone (down to 1000 km depth), at least partly driven from below. From mass balance considerations in a viscous Earth, we show that the density excess required in the hot upwelling limbs may reflect the formation of stable dense lenses of dehydration-induced partial melt atop the 410 km discontinuity, and upward entrainment of a small fraction of quasi-buoyant partially molten and recrystallized material across the upper mantle. Our model provides an explanation for the thin low shear velocity layer detected intermittently above the 410 km discontinuity in some parts of ocean basins away from subducted slabs, and supports the presence of water in the transition zone.

Analysis and performance evaluation of computation models for node localization in deep sea using UWSN

SummaryUnderwater wireless sensor network (UWSN) connects the real world to the hidden resources available deep into the sea using sensor nodes deployed sparsely and are interconnected to gather information for any movement/change in the ocean. The computed information on nodes obtained from concurrently running UWSN's applications will be meaningful, only if the location of this change will be identified. Nevertheless, it is always difficult to obtain the exact location coordinates of any misadventure like tectonic plate's movement but using localization algorithms in UWSN helps to obtain the coordinates. Since localization algorithms for terrestrial networks are not feasible for UWSN because of environmental challenges. Moreover, GPS systems do not work after 15 m of depth and the radio frequency gets suppressed. So, the requirement arises to analyze existing localization approaches in the deep sea where acoustic signals are used for communication and data transfer. In this paper, along with describing the UWSN's applications and challenges, the underwater localization schemes are reviewed to present, summarize, and mention the scope of improvement. Further, classification into range‐based and range‐free categories of these schemes is depicted with implementation in the NS2.30 simulation environment of some of the recent techniques to showcase the reasons for better performance.

An Ellipsoidal Plate Motion Model of the Indo‐Australian Tectonic Plate

AbstractWe present a class of “ellipsoidal rotation matrices” which can be used to characterize tectonic plate motion; where geocentric Cartesian coordinates travel along paths tangential to the ellipsoid. We contrast them with conventional Euler pole plate motion models which are more closely aligned with spherical coordinate systems and inherently induce a change in geodetic ellipsoidal height. We demonstrate the use of each in the Indo‐Australian tectonic plate setting, which is known to move approximately 7 cm/year in a north‐northeast direction. Geocentric Datum of Australia 2020 (GDA2020) coordinates are “plate‐fixed” static coordinates obtained using a conventional Euler pole plate motion model to align time dependent coordinates with the 2014 realization of the International Terrestrial Reference Frame at the epoch 2020.0. We show that this Euler pole plate motion model can introduce ellipsoidal height velocities of up to −0.2 mm/year. This is small but systematic, so pertinent for consideration with high accuracy vertical land motion studies using GDA2020 coordinates and velocities. We further investigate the comparative statistical accuracy of conventional Euler pole and the ellipsoidal models with respect to characterizing plate motion captured in high quality Global Navigation Satellite System data.

Coastal Evolution of Satingpra Peninsula, Songkhla Province: Implications for Understanding Songkla Lagoon Formation

Songkhla Lagoon has been studied for decades, but there is no clear evidence of its origin. As a barrier to the lagoon, the Satingpra Peninsula plays a crucial role in understanding its formation. Eleven sediment samples from sand ridges and tidal flats on the Satingpra Peninsular were collected and analysed for granulometry and geochronology. Both coarse-grained and fine-grained quartz-rich fractions were utilised to prepare samples of aliquots. The optically stimulated luminescence (OSL) dating was performed using the single-aliquot regenerative dose method for a determined (deposited) age. In addition, previous research, geological surveys and geochronological data were combined to explain their formation in this region. The OSL ages in the present study indicated that the late Holocene regression occurred between 0.36 and 3.27 ka (ka stands for 1,000 years). Integrated with previous studies, recorded ages dating back to the mid-Holocene sea level rise (ca. 6.5 ka) and the subsequent late-Holocene decline, indicate that both the old lagoon and middle beach ridge exhibit a sand ridge formation that runs parallel to the shoreline, extending from the south to the north. The middle sand, in this study, formed from about 3.02 to 1.5 ka ago resulting in the lagoon being isolated from the sea during that time. The lagoonal tide led the deposition as the present tidal flat from 3.3 to 1.7 ka. About 2.19 ka ago, the inner and middle ridges formed due to wind-driven processes influenced by a dry climate. This was followed by a continued sea level regression, leading to the formation of the outer ridge around 1.5 ka ago when the sea level was 1.4 m below the present sea level. However, it’s essential to consider this sea level data in relation to the tectonic and human-induced land motions in the surrounding area. HIGHLIGHTS OSL ages, based on average dose model at the Northern Satingpra Peninsula were 1.04 - 3.27 ka. The old sand ridges of the Satingpra Peninsula prograde northward after mid Holocene sea level highstand. Paleo sea level based on wind-wave sediments contact was 1.4 m lower than present day at 1.46 ka. GRAPHICAL ABSTRACT

Unfolding rotational tectonics and topographic evolution from localized verses diffuse plate boundary counterparts

We present a kinematic model developed from geodetic observations, topography analysis and analogue tectonic modelling results, which reveals a striking similarity between the rotational tectonic settings of the Gakkel Ridge-Chersky Range system in the Arctic, and the Central Indian Tectonic Zone within the Indian subcontinent. A crucial aspect of large-scale extensional rift systems is the gradual variation of extension along the rift axis, due to plate rotation about a Euler pole, which may lead to contraction on the opposite side of the Euler pole to form a rotational tectonic system. Our geodetic and topographic analysis, combined with the reanalysis of analogue tectonic modelling results demonstrates such rotational tectonic plate motion in both the Arctic and Indian case. However, the plate boundary between the North American and Eurasian Plates as represented by the Arctic Gakkel Ridge-Chersky Range system is strongly localized, whereas the Central Indian Tectonic Zone that separates the North and South India Plates involves diffuse deformation instead. Furthermore, in both the Arctic and Central Indian we find that the relative Euler rotation pole is located near an indenter-like feature, which possibly controls the present-day rotational tectonics and contrasting topography on opposite sides of the Euler pole.

Research on a Comprehensive Monitoring System for Tunnel Operation based on the Internet of Things and Artificial Intelligence Identification Technology

This article proposes a comprehensive monitoring system for tunnel operation to address the risks associated with tunnel operations. These risks include safety control risks, increased traffic flow, extreme weather events, and movement of tectonic plates. The proposed system is based on the Internet of Things and artificial intelligence identification technology. The monitoring system will cover various aspects of tunnel operations, such as the slope of the entrance, the structural safety of the cave body, toxic and harmful gases that may appear during operation, excessively high and low-temperature humidity, poor illumination, water leakage or road water accumulation caused by extreme weather, combustion and smoke caused by fires, and more. The system will enable comprehensive monitoring and early warning of fire protection systems, accident vehicles, and overheating vehicles. This will effectively improve safety during tunnel operation.