Abstract Distributed Acoustic Sensing (DAS) is an emerging technology for earthquake monitoring and subsurface imaging. However, its distinct characteristics, such as unknown ground coupling high noise level, pose challenges to signal processing. Existing machine learning models optimized conventional seismic data struggle with DAS due ultra-dense spatial sampling limited manual labels. We introduce a semi-supervised approach address the phase-picking task of data. use pre-trained PhaseNet...

Abstract Distributed Acoustic Sensing (DAS) is a promising technique to improve the rapid detection and characterization of earthquakes. Previous DAS studies mainly focus on phase information but less amplitude information. In this study, we compile earthquake data from two arrays in California, USA, one submarine array Sanriku, Japan. We develop data‐driven method obtain first scaling relation between magnitude. Our results reveal that amplitudes recorded by different regions follow similar...

ABSTRACT The recorded seismic waveform is a convolution of event source term, path and station term. Removing high-frequency attenuation due to effect challenging problem. Empirical Green’s function (EGF) method uses nearly collocated small earthquakes correct the terms for larger events at same station. However, this subject variability many factors. We focus on three that were well by network rapid response distributed acoustic sensing (DAS) array. Using suite high-quality EGF events, we...

Abstract We present a real-data test for offshore earthquake early warning (EEW) with distributed acoustic sensing (DAS) by transforming submarine fiber-optic cable into dense seismic array. First, we constrain locations using the arrival-time information recorded DAS Second, site effects along calibrated an independent earthquake, estimate magnitudes directly from strain rate amplitudes applying scaling relation transferred onshore arrays. Our results indicate that this single 50 km array...

Abstract Distributed Acoustic Sensing (DAS) is an emerging technology that converts optical fibers into dense arrays of strainmeters, significantly enhancing our understanding earthquake physics and Earth's structure. While most past DAS studies have focused primarily on seismic wave phase information, accurate measurements true ground motion amplitudes are crucial for comprehensive future analyses. However, in recordings, especially pre‐existing telecommunication cables with uncertain...

Abstract On 16 September 2015, an M w 8.3 earthquake struck middle Chile due to the subduction of Nazca plate beneath South America plate. This is consequence 72 years strain accumulation in region since 1943 event. In this study, we apply compressive sensing method (CS) invert for spatiotemporal distribution coseismic radiation at different frequencies The results show clear frequency‐dependent feature rupture with low‐frequency (LF) located updip while high‐frequency (HF) concentrated...

Abstract Earthquake source time functions carry information about the complexity of seismic rupture. We explore databases earthquake and find that they are composed distinct peaks we call subevents. observe complexity, as represented by number subevents, grows with magnitude. Patterns in rupture arise from a scaling between subevent moment main event moment. These results can be explained simple 2‐D dynamic simulations self‐affine heterogeneity fault prestress. Applying this to early...

Abstract We cluster a global database of 3529 Mw>5.5 earthquakes in 1995–2018 based on dynamic time warping distance between earthquake source functions (STFs). The clustering exhibits different degrees complexity the STF shapes and suggests an association parameters. Most thrust events have simple across all depths. In contrast, with complex tend to be located at shallow depths complicated tectonic regions, exhibit long duration compared others similar magnitude, strike-slip...

Abstract Megathrust earthquakes exhibit a ubiquitous seismic radiation style: low‐frequency (LF) energy is efficiently emitted from the shallowest portion of fault, whereas high‐frequency (HF) deepest part fault. Although this observed in many case‐specific studies, we show that it global megathrust between 1995 and 2021. Previous studies have interpreted as an effect systematic depth variation either plate interface frictional properties (Lay et al., 2012) or P wavespeeds (Sallarès &...

SUMMARY Seismograms contain multiple sources of seismic waves, from distinct transient signals such as earthquakes to continuous ambient vibrations microseism. Ambient contaminate the earthquake signals, while pollute noise’s statistical properties necessary for ambient-noise seismology analysis. Separating noise would thus benefit seismological analyses. This work develops a multitask encoder–decoder network named WaveDecompNet separate directly in time domain 3-component seismograms. We...

Abstract Distributed Acoustic Sensing (DAS) is an emerging technology for earthquake monitoring and subsurface imaging. The recorded seismic signals by DAS have several distinct characteristics, such as unknown coupling effects, strong anthropogenic noise, ultra-dense spatial sampling. These aspects differ from conventional data networks, making it challenging to utilize at present monitoring. New analysis algorithms are needed extract useful information data, determining the first arrival...

Backprojection (BP) of teleseismic P waves is a powerful tool to study the evolution seismic radiation large earthquakes. The common interpretations on BP results are qualitative comparisons with earthquake kinematic observations, such as slip fault and rupture velocity. However, direct relation between images physical properties process remains unclear needed for further application this technique. In study, we start from theoretical formulation images, which linear in frequency domain,...

Abstract We develop a methodology that combines compressive sensing backprojection (CS‐BP) and source spectral analysis of teleseismic P waves to provide metrics relevant earthquake dynamics large events. improve the CS‐BP method by an autoadaptive grid refinement as well reference adjustment technique gain better spatial temporal resolution locations radiated bursts. also use two‐step based on (i) simple theoretical Green's functions include depth phases water reverberations (ii) empirical...

On 2012 April 11, a great strike-slip earthquake (moment magnitude of Mw 8.6) occurred off the west coast northern Sumatra area followed by an 8.2 aftershock 2 hr later. Different geophysical data and methods have been used to investigate mechanism, faulting, seismic radiation slip propagation this event, but frequency-dependent features its rupture process not discussed much. In study, we use compressive sensing method based on sparsity inversion in frequency domain study event. Our results...

Earth and Space Science Open Archive This work has been accepted for publication in Seismological Research Letters. Version of RecordESSOAr is a venue early communication or feedback before peer review. Data may be preliminary. Learn more about preprints. preprintOpen AccessYou are viewing the latest version by default [v2]Source time function clustering reveals patterns earthquake dynamicsAuthors Jiuxun Yin iD Zefeng Li Marine Denolle iDSee all authors YiniDHarvard...

百年来几乎整个南美洲西海岸都发生过大地震 [1,2] .智利是大地震频发的国家, 迄今为止, 人类有史以来 记录到的最大地震就是1960年在智利南部Valdivia发 生的M w 9.5级强震, 其破裂沿海沟向南延展~900 km, 最大滑移超过40 m [3] .2010年, 在9.5级地震的北缘靠 近Maule发生了M 8.8级地震, 其破裂长度约400

Distributed Acoustic Sensing (DAS) is a promising technique to improve the rapid detection and characterization of earthquakes. Due some instrumental limitations, current DAS studies primarily focus on phase information but less amplitude information. In this study, we compile earthquake data from two arrays in California, USA, one submarine array Sanriku, Japan. We develop data-driven method obtain first scaling relation between magnitude. Our results reveal that different regions follows...

Seismograms contain multiple sources of seismic waves, from distinct transient signals such as earthquakes to ambient vibrations microseism. Ambient contaminate the earthquake signals, while pollute noise’s statistical properties necessary for ambient-noise seismology analysis. Separating noise would thus benefit seismological analyses. This work develops a multi-task encoder-decoder network separate directly in time domain 3-component seismograms. We choose active-volcanic Big Island...

Earthquake source time functions carry information about the complexity of seismic rupture. We explore databases earthquakes and find that are composed distinct peaks we call subevents. observe earthquake complexity, as represented by number subevents, grows with magnitude. subevent magnitudes nearly proportional to their corresponding main event show magnitude can be estimated after observing only first few

Distributed Acoustic Sensing (DAS) is an emerging technology for earthquake monitoring and subsurface imaging. The recorded seismic signals by DAS have several distinct characteristics, such as unknown coupling effects, strong anthropogenic noise, ultra-dense spatial sampling. These aspects differ from conventional data networks, making it challenging to utilize at present monitoring. New analysis algorithms are needed extract useful information data. Previous studies on demonstrated that...