Abstract Low-frequency tremors have been widely detected in many tectonic zones, and are often located adjacent to megathrust indicating that their spatiotemporal evolution provides important insights into events. The envelope correlation method (ECM) is commonly used detect tremors. However, the ECM also detects regular earthquakes, which requires separation of these two signals after initial ...

The present day seismic activity from a region reflects the active tectonics and can confirm the seismic potential of the seismogenic sources as they are modelled using the historical seismicity. This paper makes a comparative analysis of the last decade seismicity recorded in the Banat Seismic Region (western part of Romania) and the historical seismicity of the region (Mw≥4.0). Four significa...

vspace{0.2cm}In this paper, we design a data structure for the following problem. Let $pi$ be an $x$-monotone trajectory with $n$ vertices in the plane and $epsilon >0$. We show how to preprocess $pi$ and $epsilon$ into a data structure such that for any horizontal query segment $Q$ in the plane, one can quickly determine the minimal continuous fraction of $pi$ whose Fr{'e}chet and Hausdo...

An automatic procedure is presented to retrieve rupture parameters for large earthquakes along the Sunda arc subduction zone. The method is based on standard array analysis and broadband seismograms registered within 30– 100 epicentral distance. No assumptions on source mechanism are required. By means of semblance the coherency of P waveforms is analysed at separate large-aperture arrays. Wave...

The tsunami generated by the offshore Samos Island earthquake (Mw = 7.0, 30 October 2020) is largest in Aegean Sea since 1956 CE. Our study was based on field surveys, video records, eyewitness accounts and far-field mareograms. recession leading motion most sites implying wave generation from seismic dislocation. At an epicentral distance of ~12 km (site K4, north Samos), sea recession, follow...

Ground shaking caused by earthquakes is accompanied seafloor and sub-seafloor formation fluid pressure variations in offshore areas, but there have been few collocated observations of these signals. In this work, we report seismic high-sampling-rate records the 2021 Mw 8.2 Alaska earthquake Ocean Networks Canada (ONC) NEPTUNE observatory at an epicentral distance ?2,200 km northeast Pacific Oce...

The relevance of the work is determined by necessity to develop hardware part seismic subsystem Large-Scale Research Facilities functioning at Federal Center Geophysical Survey Russian Academy Sciences study signals in groundwater pressure changes. For this purpose, well monitoring on territory Petropavlovsk-Kamchatsky test site, Kamchatka Peninsula, was updated using Keller equipment, Switzerl...

Significant hydrogeochemical changes may occur prior- and post-earthquakes. The Xiaojiang fault zone (XJF), situated in a highly deformed area of the southeastern margin Tibetan Plateau, is one active seismic areas. In this study, major trace elements, hydrogen oxygen isotopes 28 sites hot springs along XJF were investigated from June 2015 to April 2019. meteoric water acts as primary source sp...

This paper investigates possible anomalies on the occasion of ML = 3.3 earthquake, which occurred 1st January 2023 close to Guidonia Montecelio (Rome, Italy). earthquake followed another very event recorded 23 December 2022 with a magnitude 3.1 (epicentral distance less than 1 km). Seismological investigations clearly show an acceleration seismicity in preceding six months circular area about 6...

A standard technique for locating events with T phases is to pick the peak energy of T phases as the arrival time, then proceed as if it was an unscattered phase originating at the epicenter. The peak energy arrival time, however, can shift to different parts of the wave train due to incoherent scattering. We show that a 50% reduction in variance relative to picks of peak arrival times can be a...