Fraktalna analiza seizmoakustičnih signala u sedimentnim stijenama blizu površine na Kamčatki

We studied, by the mono- and multifractal detrended fluctuation analysis (DFA), time fluctuations in the dynamics of seismoacoustic data, recorded in Karymshina site, which is located in a seismic area of Kamchatka. We took a series of seismoacoustic responses to the regional seismic events with the mag-nitudes M > 4 for the period 2017–2018. The series was divided into three groups (high, medium and low) based on the amplitude of recorded seismoacoustic re-sponse. Background noise segments of the signals demonstrated monofractal behavior similar to white noise by almost constant values of generalized Hurst exponent Hq≈0.5 and very small width of the multifractal spectrum Δa ≈ 0.1. Analysis of the high amplitude seismoacoustic signals with clear P-, S- and coda waves showed that P- and S-waves demonstrate wider multifractal spectrum (ΔaP = 0.37, ΔaS = 0.35) and range of generalized Hurst exponents Hq in com-parison with coda wave, characterized by almost constant Hq and minimal width of multifractal spectrum (ΔaCODA = 0.13). We showed that the properties of the multifractal spectrum could be used in detection of seismic wave arrival, estima-tion its duration and separation of P-, S- and coda waves. Application of the monofractal DFA in a sliding window showed that the acoustic signal transits from monofractal and uncorrelated background noise (Hurst exponent equals to 0.5) into the long-range dependent state during seismic waves arrival, that is helpful in analysis of the signals, particularly in case of low amplitude acous-tic responses, usually demonstrating an unclear waveform. Difference in mul-tifractal spectrum width between the original low amplitude signal and its sur-rogates, obtained by random shuffling showed that the multifractality in the signal is dominantly due to long-range correlations.U ovom smo radu mono- i multifraktalnom detrendiranom fluktuacijskom analizom (DFA) proučavali vremenske fluktuacije u dinamici seizmoakustičnih podataka zabilježe-nih na postaji Karymshina, koja je smještena u seizmički aktivnom području Kamčatke. U analizi smo koristili niz seizmoakustičnih odziva prilagođenih na regionalne potrese s magnitudama M > 4 za razdoblje 2017.–2018. Niz smo podijelili u tri grupe (visoka, sred-nja i niska) na temelju amplitude zabilježenog seizmoakustičnog odziva. Dio mikroseiz-mičkog nemira prisutnog unutar signala iskazuje monofraktalnu strukturu sličnu bijelom šumu s gotovo konstantnim vrijednostima generaliziranog Hurstovog eksponenta Hq ≈ 0,5 i vrlo malom širinom multifraktalnog spektra Δa ≈ 0,1. Analiza seizmoakustičnog signa-la visoke amplitude s jasnim P-, S- i koda valovima pokazala je da P- i S-valovi pokazuju širi multifraktalni spektar (ΔaP = 0,37, ΔaS = 0,35) i raspon generaliziranih Hurstovih eksponenata Hq u usporedbi s koda valovima, koje karakterizira gotovo konstantan Hq i minimalna širina multifraktalnog spektra (ΔaCODA = 0,13). Pokazali smo da se svojstva multifraktalnog spektra mogu upotrijebiti za otkrivanje nailaska seizmičkih valova, pro-cjenu nihovog trajanja i razdvajanje P-, S- i koda valova. Primjena monofraktalne DFA metode na zapise u kliznom prozoru pokazala je da akustički signal prelazi iz monofrak-talnog i nekoreliranog mikroseizmičkog nemira (Hurstov eksponent jednak 0,5) u stanje dugog dometa tijekom dolaska seizmičkih valova, što je korisno u analizi signala, poseb-no u slučaju akustičnih odziva niske amplitude s nejasnim valnim oblikom. Razlika u širini multifraktalnog spektra između izvornog signala niske amplitude i njegovih zam-jenskih oblika, dobivenih nasumičnim odabirom, ukazuje da multifraktalnost u signalu dominantno ovisi o dalekosežnim korelacijama

Диагностирование аномалий температуры атмосферы в сейсмически активных регионах Азии по спутниковым данным

Results of diagnosis of temperature anomalies based on retrospective analysis of long-term timeseries of temperature in separation zone of troposphere and stratosphere over epicenters of 10 strong earthquakes with magnitude of M>6.5 that occurred in different seismically active regions of Asia are presented. Anomalous temperature perturbations were observed in all the studied cases 1-8 days before the main seismic eventПредставлены результаты диагностирования аномалий температуры, основанные на ретроспективном анализе долговременных спутниковых данных в зоне раздела тропосферы и стратосферы над эпицентрами 10 сильных землетрясений магнитудой M>6,5, произошедших в различных сейсмически активных регионах Азии. Аномальные возмущения температуры наблюдались во всех рассмотренных случаях за 1−8 дней до основного сейсмического событи

Atmospheric temperature coherent variations effects, preceding strong earthquakes

We analyzed satellite measurements of temperature at upper troposphere/lower stratosphere (UTLS) levels separated by the tropopause above the epicentral area of a strong earthquake with a magnitude of M=7.3 in the Northern Tien-Shan (Kyrgyzstan) that took place on August 19, 1992. The developed algorithm and method of continuous wavelet transform allowed detecting of abnormal behavior, temporal, spatial and spectral coherence of short-period temperature variations, preceding the seismic event. The results show that the spatial structure and dynamics of temperature anomalies in the area of UTLS have a sufficiently stable relation to seismic activity

Study of coherence of temperature variations in the tropopause associated with earthquakes

The paper presents retrospective analysis of satellite data of the upper troposphere / lower stratosphere over the epicentral area of the destructive earthquake of M=6.7, occurred in Tien-Shan territory. We established a well-defined temporal and spatial coherence between temperature perturbations and seismic activity. We used wavelet analysis to identify temporal and spectral coherence of temperature variations in a boundary zone of troposphere and stratosphere before the seismic event

Anomalous atmospheric temperature perturbations over seismically active regions of Europe according to satellite measurements

An algorithm for defining temperature anomalies and the results of diagnostic studies, based on a retrospective analysis of time series of satellite data in troposphere and stratosphere over the epicenters of strong earthquakes with magnitude M > 6.0, occurring in seismically active Mediterranean region of Europe are presented. It was found out that in all cases anomalous temperature disturbances were registered 1-10 days before the main seismic event

Atmospheric Temperature Anomalies During Seismic Activity

Представлены результаты, полученные с использованием разработанной методики диагностирования аномалий температуры и основанные на ретроспективном анализе процессов трансформации профилей температуры в зоне раздела тропосферы и стратосферы над эпицентрами землетрясений энергетического класса K>13.0, произошедших в Северном и Центральном Тянь-Шане с 2003 по 2015 г. Аномальные возмущения температуры наблюдались примерно в 70 % случаев за 1-5 дней до основного сейсмического событияPresented results were obtained by means of methods of temperature anomalies diagnosing and on the basis of retrospective analysis of temperature profiles transformation in border of troposphere and stratosphere over epicenters of earthquakes with energy class of K>13.0, occurred in Northern and Central Tien-Shan during 2003-2015. Abnormal temperature perturbations observed in about 70% of cases in 1–5 days before the main seismic even

Atmospheric Temperature Anomalies During Seismic Activity

Представлены результаты, полученные с использованием разработанной методики диагностирования аномалий температуры и основанные на ретроспективном анализе процессов трансформации профилей температуры в зоне раздела тропосферы и стратосферы над эпицентрами землетрясений энергетического класса K>13.0, произошедших в Северном и Центральном Тянь-Шане с 2003 по 2015 г. Аномальные возмущения температуры наблюдались примерно в 70 % случаев за 1-5 дней до основного сейсмического событияPresented results were obtained by means of methods of temperature anomalies diagnosing and on the basis of retrospective analysis of temperature profiles transformation in border of troposphere and stratosphere over epicenters of earthquakes with energy class of K>13.0, occurred in Northern and Central Tien-Shan during 2003-2015. Abnormal temperature perturbations observed in about 70% of cases in 1–5 days before the main seismic even

Features of atmospheric disturbances in temperate latitudes before strong earthquakes (M> 7) according to satellite measurements

An ATOVS and MERRA data archive containing temperature values at isobaric levels from 1000 to 50 hPa was formed to study the atmospheric effects observed over the foci of two strong earthquakes with magnitudes M = 7,3. The first seismic event was recorded on August 19, 1992 in the northern Tien Shan and the second on November 12, 2017 in the border areas of the Zagros folded mountain belt. According to USGS intense aftershock activity in these regions began with these seismic events. Using correlation and spectral analysis we studied the vertical profiles of temperature and pressure in a disturbed atmosphere over seismically active regions. The modified anomaly index was calculated at isobaric levels from 500 to 50 hPa and on its basis the registered temperature anomalies were investigated

Features of atmospheric disturbances in temperate latitudes before strong earthquakes (M> 7) according to satellite measurements

An ATOVS and MERRA data archive containing temperature values at isobaric levels from 1000 to 50 hPa was formed to study the atmospheric effects observed over the foci of two strong earthquakes with magnitudes M = 7,3. The first seismic event was recorded on August 19, 1992 in the northern Tien Shan and the second on November 12, 2017 in the border areas of the Zagros folded mountain belt. According to USGS intense aftershock activity in these regions began with these seismic events. Using correlation and spectral analysis we studied the vertical profiles of temperature and pressure in a disturbed atmosphere over seismically active regions. The modified anomaly index was calculated at isobaric levels from 500 to 50 hPa and on its basis the registered temperature anomalies were investigated

Lidar Measurements of the Vertical Distribution of Aerosol Optical and Physical Properties over Central Asia

The vertical structure of aerosol optical and physical properties was measured by Lidar in Eastern Kyrgyzstan, Central Asia, from June 2008 to May 2009. Lidar measurements were supplemented with surface-based measurements of PM2.5 and PM10 mass and chemical composition in both size fractions. Dust transported into the region is common, being detected 33% of the time. The maximum frequency occurred in the spring of 2009. Dust transported to Central Asia comes from regional sources, for example, Taklimakan desert and Aral Sea basin, and from long-range transport, for example, deserts of Arabia, Northeast Africa, Iran, and Pakistan. Regional sources are characterized by pollution transport with maximum values of coarse particles within the planetary boundary layer, aerosol optical thickness, extinction coefficient, integral coefficient of aerosol backscatter, and minimum values of the Ångström exponent. Pollution associated with air masses transported over long distances has different characteristics during autumn, winter, and spring. During winter, dust emissions were low resulting in high values of the Ångström exponent (about 0.51) and the fine particle mass fraction (64%). Dust storms were more frequent during spring with an increase in coarse dust particles in comparison to winter. The aerosol vertical profiles can be used to lower uncertainty in estimating radiative forcing