This paper presents a tomographic study on the S wave velocity structure of China and adjacent regions. Group dispersions fundamental Rayleigh waves along more than 4000 paths were determined with frequency‐time analysis. The region was divided into 1° × grid, velocities in between grid nodes calculated by bilinear interpolation. Occam's inversion scheme adopted to invert for group distributions. method is robust allows us use fine model parameterization thus helps restore realistic pattern....

Abstract The two principle earthquakes of the July 2019 Ridgecrest, California, earthquake sequence, M W 6.4 and 7.1, their immediate foreshocks thousands aftershocks present a challenging environment for rapid analysis characterization this sequence as it unfolded. In study, we analyze first 6 days using continuous data from available seismic networks to detect locate associated with sequence. We build high‐precision catalog deep‐neural‐network‐based picker—PhaseNet sequential association...

Abstract We collected continuous seismic data recorded between 2007 and 2010 by 208 broadband stations from the Chinese Provincial Digital Seismic Networks, A Collaborative Experiment of Northern Tibet, Northeastern Tibet experiment. Cross correlations vertical component records are computed to extract Rayleigh wave empirical Green's functions. Group phase velocities then constructed functions in 8 50 s period. At periods ≤25 s, more than 10% lower imaged beneath Qaidam Basin, high observed...

Abstract Volcanic regions commonly host swarms comprising small to moderate-sized earthquakes while tectonic faults mostly mainshock-aftershock sequences that can include very large earthquakes. In the southeastern Tibetan Plateau, formed by collision between Indian and Eurasian plates intersect with intraplate Tengchong volcanic field, seismic behavior of such an environment remains unclear. Here, we built a deep-learning-based high-precision earthquake catalog for field found (1) ~59%...

Abstract We conduct a nonlinear joint inversion of receiver functions and surface waves to obtain the lithosphere structure in east‐central China. also use SKS splitting measurements evaluate upper mantle deformation. The velocity model reveals that, east North‐South Gravity Lineament, crust are significantly thinned. Three extensive crustal/lithospheric thinning subregions identified. This indicates that lithospheric modification China is nonuniform due heterogeneity strength. Extensive...

Abstract Zhejiang Suichang native honey, which is included in the list of China’s National Geographical Indication Agricultural Products Protection Project, very popular. This study proposes a method Raman spectroscopy combined with machine learning algorithms to accurately detect low-concentration adulterated honey. In this study, honey collected by local beekeepers was selected for adulteration detection. The spectral data compressed Savitzky–Golay smoothing and partial least squares (PLS)...

Both the rich mineralization in Lower Yangtze Block (LYB) and post-collisional mafic rocks Dabie Orogen (DBO) are closely related to Cretaceous magmatism east-central China. Various geodynamic models have been proposed for explaining mechanism of magmatism, but these controversial even contradictory with each other, especially on adakites. A unified model is required China, particular, spatial temporal correlations magmatic activity DBO that LYB. For this purpose, we apply teleseismic...

Abstract On 21 May 2021, an M S 6.4 earthquake occurred in Yangbi, Yunnan province, China. A significant foreshock sequence 3 days before the mainshock, which provides opportunity to study nucleation. In this study, we adopt a template matching technique and double‐difference location method build catalog for of 2021 Yangbi earthquake, contains 1,086 events with high‐precision locations. The whole can be grouped into four episodes, each one W > 3.7 principal foreshock. foreshocks within...

We present the surface wave dispersion results of application ambient noise method to broad-band data recorded at 114 stations from Istituto Nazionale di Geofisica e Vulcanologia (INGV) national network, some Mediterranean Very Broadband Seismographic Network (MedNet) and Austrian Central Institute for Meteorology Geodynamics (ZAMG). Vertical-component 2005 October 2007 March have been cross-correlated station-pairs estimate fundamental mode Rayleigh Green's functions. Cross-correlations are...

In this paper, we conduct ambient noise seismic tomography of northwestern China and adjacent regions. The data include 9 months (2009 January to 2009 September) three-component continuous recorded at 146 stations newly upgraded Provincial Digital Seismic Networks regional Kyrgyzstan Kazakhstan networks. Empirical Rayleigh Love wave Green′s functions are obtained from interstation cross-correlations. Group velocity dispersion curves for both waves between 7 50 s periods were measured each...

With the aging of society, cognitive impairment in elderly people is becoming increasingly common and has caused major public health problems. The screening its related influencing factors can aid development relevant intervention improvement strategies. In this study, stratified random cluster sampling was used to conduct a cross-sectional survey individuals aged 65 years Chengdu, Sichuan Province, through an electronic questionnaire from November 2022 2023. Descriptive analysis logistic...

The fault damage zone is a region surrounding an earthquake interface where rocks are significantly fractured due to tectonic movements and historical large earthquakes on the fault. rock fractures within absorb scatter seismic waves, causing amplitude decay in different frequency ranges. In this study, we use ambient noise attenuation tomography image zones two settings: transform southern California thrust western Sichuan. According dynamic rupture models, preferred direction leads...

The Mw 7.0 Dingri earthquake, which occurred on 7 January 2025, at the southern end of Xainza-Dinggyê Fault Zone within South Tibet Rift (STR) system, in Dengmecuo graben. It is largest normal-faulting event region recorded by modern instruments. Using Sentinel-1A and Lutan SAR data combined with strong-motion records, we derived coseismic surface deformation slip distribution. InSAR interferograms displacement vectors confirm a typical pattern. model, based an elastic half-space assumption,...

High-frequency body waves recorded by a temporary seismic array across the surface rupture trace of 1992 Landers, California, earthquake were used to determine fault-zone structures down seismogenic depth. We first developed technique use generalized ray theory compute synthetic seismograms for arbitrarily oriented tabular low-velocity models. then generated waveform record sections linear vertical fault zone. They show that both arrival times and waveforms P S vary systematically due...

Abstract The northeastern Tibetan Plateau has undergone active shortening due to the India‐Asia collision and been an ideal place for studying growth of plateau. To reveal deep structure that is responsible geological observations in NE Tibet, we have constructed a 3‐D shear wave velocity model from Rayleigh waves recorded by 36 stations Northeast Seismic experiment. First, two‐plane‐wave tomography method was applied compute average 2‐D variations phase velocities period range 20 100 s....

The crustal and upper mantle velocity structure in the northeastern Tibetan Plateau is obtained from joint analysis of receiver functions Rayleigh wave dispersions. resulting model reveals a close correlation between thick (>60 km) crust presence an intracrustal low-velocity zone beneath Qiangtang Songpan-Ganzi terranes as well northwestern Qilian orogen. However, high Vp/Vs ratio found only terranes. low does not appear west Qinling southeastern orogens, which have relatively thin (∼50...

We examine seismic anisotropy beneath eastern China by analysing shear wave splitting of teleseismic SKS, SKKS and PKS phases recorded at 402 permanent temporary stations. In general, our fast directions are approximately oriented in the E–W direction. The delay times vary greatly between 0.5 1.9 s. stations Sichuan basin less than 0.8 s, which could explain fossilized lithospheric mantle little deformation after formation stable block. Qinling–Dabie orogenic belts orient NWW–SEE, NEE–SWW,...

The northeastern margin of the Tibetan Plateau (NE Plateau) exhibits active geological structures and has experienced multiple strong earthquakes, with M ≥ 7, throughout history. Particularly noteworthy is 1920 M81/2 earthquake in Haiyuan region that occurred a century ago documented as one deadliest earthquakes. Consequently, analyzing seismic risks holds significant importance. b value, crucial parameter for activity, plays pivotal role hazard analyses. This study calculates spatial values...

Streamflow simulation is crucial for flood mitigation, ecological protection, and water resource planning. Process-based hydrological models machine learning algorithms are the mainstream tools streamflow simulation. However, their inherent limitations, such as time-consuming large data requirements, make achieving high-precision simulations challenging. This study developed a hybrid approach to simultaneously improve accuracy computational efficiency of simulation, which integrates...

Abstract High‐resolution seismic model is crucial for advancing our understandings on geological processes and enhancing hazard mitigation programs. We construct a high‐resolution China Seismological Reference Model (CSRM‐1.0) in the top 100 km of crust uppermost mantle continental following top‐down construction process. The employed constraints include P‐ wave polarization angle from tele‐seismic event, short‐period Rayleigh ellipticity ambient noise, long‐period earthquake data, receiver...