[1] Earthquake Early Warning (EEW) algorithms estimate the magnitude of an underway rupture from the first few seconds of the P-wave to allow hazard assessment and mitigation before the S-wave arrival. Many large subductionzone earthquakes initiate 50–150 km offshore, potentially allowing seafloor instruments sufficient time to identify large ruptures before the S-waves reach land. We tested an...

Full-waveform seismic inversions based on minimizing the distance between observed and predicted seismograms are, in principle, able to yield better-resolved earth models than those minimizing misfits derived from traveltimes alone. Adjoint-based methods provide an efficient way of calculating the gradient of the misfit function via a sequence of forward-modeling steps, which, using spectral-el...

Source parameters of 15 large (mb -> 6) earthquakes which occurred near Taiwan during the last 25 years are determined by synthetic seismogram analysis of teleseismic P and S waveforms. Source depths range from 13 to 88 km. Three earthquakes of intermediate depth are located within the southernmost limit of the Ryukyu arc and show thrust-type mechanisms with T axes subparallel to a northward di...

Abstract. The Bohemian Massif exposes structures and metamorphic rocks remnant from the Variscan orogeny in central Europe is bordered by Franconian Fault System (FFS) to west. Across FFS, units are buried Permo-Mesozoic sedimentary rocks. We integrate existing DEKORP 2D seismic reflection, well, surface geological data with newly acquired FRANKEN survey investigate possible westward continuati...

Abstract The correct absolute time of a seismogram is an important prerequisite for many seismological processing methods. Recently, seismic interferometry has been applied to continuously estimate instrumental clock errors in certain regions. However, previous studies have focused on estimating only one target region each study, and data methods that provide more stable results different regio...

The seismic reflection method has a primary role in petroleum exploration. This research is structural interpretation study of the 2D survey carried out Upper West Euphrates (Khan Al-Baghdadi area), which located western part Iraq, Al-Anbar governorate. two objectives this are to interpret Base Akkas/Top Khabour reflector and define potential hydrocarbon traps surveyed area. Based on synthetic ...

Recent studies of deep mantle structure indicate strong heterogeneity. To conduct highresolution waveform modelling of these structures, we have developed a new method to construct 2-D synthetics directly from block-style tomographic models. Unlike the WKBJ approximation, which utilizes rays overshooting and undershooting receivers, our method (WKM approximation) uses rays that arrive at the re...

Well-seismic ties allow rock properties measured at well locations to be compared to seismic data, and therefore are useful for seismic interpretation. Numerous methods have been proposed to compute well-seismic ties by correlating real seismograms with synthetic seismograms computed from velocity and density logs. However, most methods tie multiple wells to seismic data one-by-one, and therefo...

Seismic oceanographic studies from various oceans worldwide have indicated that the acoustic reflections are mostly observed along thermal boundaries within the water column. However, the authors present a case study of seismic data from Krishna-Godavari Basin which shows that salinity variations also play an important role in the occurrence of water column reflections. The observed reflection ...