Preprints
Search for earthquake (503 results)
Rupture phase in near-fault records of the 2023 Turkey Mw 7.8 earthquake
Published: 2023-04-28
Subjects: Physical Sciences and Mathematics
Understanding and deciphering wiggles especially coherent phases from seismograms have been a long endeavor to understand the earth structure and earthquake source. However, coherent phases directly associated with earthquake rupture propagation have not been available due to the lack of continuous near-fault observations. Here we report the rupture phase as large velocity pulses during the 2023 [...]
A machine learning-based thermometer, barometer and hygrometer for magmatic liquids
Published: 2023-04-27
Subjects: Physical Sciences and Mathematics
Experimentally calibrated models to recover pressures, temperatures and water contents of magmas, are widely used in igneous petrology. However, large errors, especially in barometry, limit the capacity of these models to resolve the architecture of crustal igneous systems. Here we apply machine learning to a large experimental database to calibrate new regression models that recover P-T-H2O of [...]
Earth tides can reactivate shallow faults and trigger seabed methane emissions
Published: 2023-04-26
Subjects: Earth Sciences
The role of solid Earth tide in fault reactivation has significant implications for understanding earthquake triggering, carbon sequestration, and the global carbon budget. Despite extensive research on this topic over the years, the relationship between Earth tide and fault reactivation remains unclear. In this study, we investigate the potential influence of solid Earth tide on the reactivation [...]
In-situ frictional behavior of subducting sediment in the shallow Nankai Trough
Published: 2023-04-22
Subjects: Geology, Geophysics and Seismology, Sedimentology, Tectonics and Structure
The transition from smectite to illite at around the depth with temperature of ~150 °C has long been hypothesized as one of controlling factors of the updip limit depth of the seismogenic zone of subduction zones. Although illite has a higher friction coefficient than smectite, previous friction experiments have little reported that the smectite-illite transition accompanies the transition from [...]
Bayesian estimation of nonlinear centroid moment tensors using multiple seismic data sets
Published: 2023-03-27
Subjects: Earth Sciences, Geophysics and Seismology
Centroid moment tensor (CMT) parameters of earthquakes are routinely estimated to gain information on structures and regional tectonics. However, for small earthquakes (M<4), it is still challenging to determine CMTs due to the lack of high-quality waveform data. In this study, we propose to improve solutions for small earthquakes by incorporating multiple seismic data types in Bayesian joint [...]
Displacement hazard from distributed ruptures in strike-slip earthquakes
Published: 2023-03-19
Subjects: Engineering, Physical Sciences and Mathematics
Widespread distributed fracturing during earthquakes threatens infrastructure and lifelines. We combine high-resolution rupture maps from the five major surface-rupturing strike-slip earthquakes in southern California and northern Mexico since 1992 to incorporate the displacements produced by distributed ruptures into a probabilistic displacement hazard analysis framework. Through analysis of the [...]
A scoping review of seismic risk communication in Europe
Published: 2023-03-15
Subjects: Physical Sciences and Mathematics, Social and Behavioral Sciences
Although earthquakes are a threat in many countries and considerable resources have been invested in safety regulations, communities at risk often lack awareness and preparedness. Risk communication is a key tool for building resilient communities, raising awareness, and increasing preparedness. Over the past 2 decades, seismic risk communication has evolved significantly. This has led to a [...]
Complex rupture evolution of the 2007 Martinique earthquake: a non-double-couple event in the Caribbean Sea
Published: 2023-03-14
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
A large non-double-couple component of a tectonic earthquake indicates that its rupture likely was complex and likely involved multiple faults. Detailed source models of such earthquakes can add to our understanding of earthquake source complexity. The 2007 Martinique earthquake in the Caribbean Sea is one of the largest recent earthquakes with a known large non-double-couple component. It was an [...]
Asperity-like (segmented) structure of the 6 February 2023 Turkish earthquakes
Published: 2023-03-10
Subjects: Geophysics and Seismology
Key to studies of the rupture process is the identification of its major segmentation into asperities. Common multi-parametric methods invert for a continuous slip distribution; they usually rely on a predefined fault position, nucleation point, planarity, smoothing, etc. Here we propose more flexible low-parametric inversions - multi-point seismic source models, and multi-patch GPS models. We [...]
Largest aftershock nucleation driven by afterslip during the 2014 Iquique sequence
Published: 2023-03-10
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Various earthquake models predict that aseismic slip modulates the seismic rupture process but actual observations of such seismic-aseismic interaction are scarce. We analyze seismic and aseismic processes during the 2014 Iquique earthquake sequence. High-rate Global Positioning System (GPS) displacements demonstrate that most of the early afterslip is located downdip of the M 8.1 mainshock and [...]
Multi-scale rupture growth with alternating directions in a complex fault network during the 2023 south-eastern Türkiye and Syria earthquake doublet
Published: 2023-03-03
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
A devastating doublet of earthquakes with moment magnitude Mw 7.9 and Mw 7.6 earthquakes contiguously occurred in SE Türkiye near the NW border of Syria. Here we perform a potency-density tensor inversion to simultaneously estimate rupture evolution and fault geometry for the doublet. We find the initial Mw 7.9 earthquake involved discrete episodes of supershear rupture and back-rupture [...]
Sub- and super-shear ruptures during the 2023 Mw 7.8 and Mw 7.6 earthquake doublet in SE Türkiye
Published: 2023-02-20
Subjects: Earth Sciences, Physical Sciences and Mathematics
An earthquake doublet (Mw 7.8 and Mw 7.6) occurred on the East Anatolian Fault Zone (EAFZ) on February 6th, 2023. The events produced significant ground motions and caused major impacts to life and infrastructure throughout SE Türkiye and NW Syria. Here we show the results of earthquake relocations of the first 11 days of aftershocks and rupture models for both events inferred from the kinematic [...]
False positives are common in single-station template matching
Published: 2023-02-17
Subjects: Earth Sciences, Geophysics and Seismology, Planetary Geophysics and Seismology, Planetary Sciences
Template matching has become a cornerstone technique of observational seismology. By taking known events, and scanning them against a continuous record, new events smaller than the signal-to-noise ratio can be found, substantially improving the magnitude of completeness of earthquake catalogues. Template matching is normally used in an array setting, however as we move into the era of planetary [...]
Curated Pacific Northwest AI-ready Seismic Dataset
Published: 2023-02-16
Subjects: Geophysics and Seismology
The curation of seismic data sets is the cornerstone of seismological research and the starting point of machine-learning applications in seismology. We present a 21-year-long AI-ready data set of diverse seismic event parameters, instrumentation metadata, and waveforms, as curated by the Pacific Northwest Seismic Network and ourselves. We describe the earthquake catalog and the temporal [...]
Evidence of Early Supershear Transition in the Feb 6th 2023 Mw 7.8 Kahramanmaraş Turkey Earthquake From Near-Field Records
Published: 2023-02-15
Subjects: Aerospace Engineering, Civil and Environmental Engineering, Earth Sciences, Engineering, Mechanical Engineering, Physical Sciences and Mathematics
The Mw7.8 Kahramanmaraş Earthquake was larger and more destructive than what had been expected for the tectonic setting in Southeastern Turkey. By using near-field records we provide evidence for early supershear transition on the splay fault that hosted the nucleation and early propagation of the first rupture that eventually transitioned into the East Anatolian fault. We also find, for the [...]