scholarly journals SOME FEATURES OF ATMOSPHERIC-LITHOSPHERIC OBSERVATIONS OF ACOUSTIC EMISSION AT «KARYMSHINA» SITE IN KAMCHATKA

2019 ◽  
pp. 94-99
Author(s):  
И.А. Ларионов ◽  
Ю.В. Марапулец
Keyword(s):  
Acoustic Emission ◽  
Ground Surface ◽  
Noise Effect ◽  
Near Surface ◽  
Laser Strainmeter ◽  
Tectonic Processes

Излагаются результаты комплексных наблюдений акустического излучения в приповерхностных породах и в атмосфере у поверхности земли. Инструментами наблюдений служат лазерный деформограф-интерферометр и микробарометр, установленные в непосредственной близости друг от друга. В работе приводится описание способа установки оборудования, показано как влияние метеорологических помех на исследуемые величины, так и возмущения, обусловленные сейсмическими и тектоническими процессами. The results of complex observations of acoustic emission in the near surface rocks and by the ground surface in the atmosphere are presented. The observation instrumentation includes a laser strainmeter-interferometer and a microbarometer installed in the intermediate vicinity from each other. The paper describes the method of instrumentation installation, meteorological noise effect on the values under the study and disturbances determined by seismic and tectonic processes.

scholarly journals Simultaneous lithospheric-atmospheric signals of acoustic emission at “Karymshina” site in Kamchatka

2021 ◽  
Vol 254 ◽  
pp. 02013
Author(s):  
Igor Larionov ◽  
Yuriy Marapulets ◽  
Mikhail Mishchenko
Keyword(s):  
Acoustic Emission ◽  
Active Region ◽  
Ground Surface ◽  
Wide Band ◽  
Kamchatka Peninsula ◽  
Acoustic Signals ◽  
Rock Deformation ◽  
Acoustic System ◽  
Near Surface ◽  
Atmosphere Interaction

We present the results of complex lithospheric-atmospheric investigations of acoustic emission in a seismically active region (Kamchatka peninsula). A laser strainmeter-interferometer, a geophone, a wide-band acoustic system and a microbarometer, installed at Karymshina site (IKIR FEB RAS), are used in the monitoring. Rock deformation, acoustic emission in the near-surface rocks and in the atmosphere by the ground surface are under the consideration. Moreover, we suggest a method to detect acoustic signals recorded simultaneously in the near-surface rocks and in the atmosphere by the ground surface. The method consists in filtration of acoustic signals from the sensors at different frequency sub-ranges from fractions to the first hundreds of hertz followed by detection and accumulation of on 1-second interval. We analyze the data from September 2016 to December 2020. Examples of records of simultaneous acoustic signals in rocks and in the atmosphere are illustrated. The investigation is topical for the construction of a model of lithosphere-atmosphere interaction in a seismically active region.

scholarly journals ESTIMATION OF LONG-RANGE CORRELATION SCALES BY SEISMOACOUSTIC EMISSION SIGNALS OF NEAR-SURFACE SEDIMENTARY ROCKS IN KAMCHATKA

2019 ◽  
pp. 190-200
Author(s):  
В.Н. Сычёв ◽  
М.А. Мищенко ◽  
С.А. Имашев ◽  
М.Е. Чешев
Keyword(s):  
Long Range ◽  
Ground Surface ◽  
Frequency Range ◽  
Self Similarity ◽  
Observation Site ◽  
Near Surface ◽  
Long Range Correlations ◽  
Seismic Receiver ◽  
Range Correlation ◽  
Geophysical Observation

На Камчатке в пункте комплексных геофизических наблюдений ИКИР ДВО РАН Карымшина для регистрации сигналов сейсмоакустической эмиссии на поверхности земли установлен измерительный комплекс. В качестве датчика сигналов используется трехкомпонентный пьезокерамический сейсмоприемник, который регистрирует колебательное ускорение в частотном диапазоне 0.5-400 Гц. Рассмотрен сейсмоакустический отклик на несколько региональных землетрясений с энергетическим классом Ks 11:0 в период 2017-2018 гг. При помощи статистических методов установлено самоподобие их структуры на ограниченном интервале временных масштабов. Это, в свою очередь, указывает на наличие дальних корреляций в рассматриваемой системе и позволяет получить оценку масштабов корреляций. A measurement complex is installed on the ground surface at Karymshina complex geophysical observation site of IKIR FEB RAS (Kamchatka) to record seismoacoustic emission signals. A three-component piezoceramic seismic receiver, which records oscillatory acceleration in the frequency range from 0.2 to 400 Hz, is used as the signal sensor. A series of seismoacoustic responses on regional earthquakes of 2017-2018 with the energy class Ks 11:0 has been considered. Self-similarity of their structures has been established in a limited interval of time scales by statistical methods. That, in its turn, indicates the presence of long-range correlations in the system under consideration and allows one to estimate correlation scales.

scholarly journals Ground thermal and geomechanical conditions in a permafrost-affected high-latitude rockslide site (Polvartinden, Northern Norway)

2016 ◽  
Author(s):  
Regula Frauenfelder ◽  
Ketil Isaksen ◽  
Jeannette Nötzli ◽  
Matthew J. Lato
Keyword(s):  
Temperature Regime ◽  
Laser Scanning ◽  
Ground Surface ◽  
Failure Zone ◽  
Climate Data ◽  
Conduction Model ◽  
Near Surface ◽  
Northern Norway ◽  
Surface Temperatures

Abstract. In June 2008, a rockslide detached in the northeast facing slope of Polvartinden, a high-alpine mountain in Signaldalen, Northern Norway. Here, we report on the observed and modelled past and present near-surface temperature regime close to the failure zone, as well as on a subsequent simulation of the subsurface temperature regime, and on initial geomechanical mapping based on laser scanning. The volume of the rockslide was estimated to be approximately 500 000 m3. The depth to the actual failure surface was found to range from 40 m at the back of the failure zone to 0 m at its toe. Visible in-situ ice was observed in the failure zone just after the rockslide. Between September 2009 and August 2013 ground surface temperatures were measured with miniature temperature data loggers at fourteen different localities close to the original failure zone along the northern ridge of Polvartinden, and in the valley floor. The results from these measurements and from a basic three-dimensional heat conduction model suggest that the lower altitudinal limit of permafrost at present is at 600–650 m a.s.l., which corresponds to the upper limit of the failure zone. A coupling of our in-situ data with regional climate data since 1958 suggests a general gradual warming and that a period with highest mean near surface temperatures on record ended four months before the Signaldalen rockslide detached. A comparison with a transient permafrost model run at 10 m depth, representative for areas where snow accumulates, strengthen this findings, which are also in congruence with measurements in nearby permafrost boreholes. It is likely that permafrost in and near the failure zone is presently subject to degradation. This degradation, in combination with the extreme warm year antecedent to the rock failure, is seen to have played an important role in the detaching of the Signaldalen rockslide.

Field Observations of Cyclical Pipe-Soil Interactions in Permafrost Terrain, KP 5, Norman Wells Pipeline, Canada

2000 ◽  
Author(s):  
Margo M. Burgess ◽  
Scott Wilkie ◽  
Rick Doblanko ◽  
Ibrahim Konuk
Keyword(s):  
Small Diameter ◽  
Ground Surface ◽  
Thermal Conditions ◽  
Field Work ◽  
Low Density ◽  
Freezing And Thawing ◽  
Near Surface ◽  
Oil Pipeline ◽  
Right Of Way ◽  
Discontinuous Permafrost

The Norman Wells pipeline is an 869 km long, small diameter, buried, ambient temperature, oil pipeline operated by Enbridge Pipeline (NW) Inc. in the discontinuous permafrost zone of northwestern Canada. Since operation began in 1985, average oil temperatures entering the line have been maintained slightly below 0°C, initially through constant chilling year round and since 1993 through a seasonal cycling of temperatures through a range from −4 to +9°C. At one location, 5 km from the inlet at Norman Wells, on level terrain in an area of widespread permafrost, uplift of a 20 m segment of line was observed in the early 1990s. The uplift gradually increased and by 1997 the pipe was exposed 0.5 m above the ground surface. Detailed studies at the site have included field investigations of terrain and thermal conditions, repeated pipe and ground surface elevation surveys, and annual Geopig surveys. The field work has revealed that the section of line was buried in low density soils, thawed to depths of 4 m on-right-of-way, and not subjected to complete refreezing in winter. The thaw depths are related to surface or near-surface flows from a nearby natural spring, as well as to the development of a thaw bulb around the pipe in the cleared right-of-way. Icings indicative of perennial water flow occur commonly at this location in the winter. The pipe experienced annual cycles of heave and settlement (on the order of 0.5 m) due to seasonal freezing and thawing within the surrounding low density soils. The pipe reached its highest elevation at the end of each winter freezing season, and its lowest elevation at the end of the summer thaw period. Superimposed on this heave/settlement cycle was an additional step-like cycle of increasing pipe strain related to thermal expansion and contraction of the pipe. A remedial program was initiated in the winter of 1997–98 in order to curtail the cumulative uplift of the pipe, reduce the increasing maximum annual pipe strain and ensure pipe safety. A 0.5 m cover of sandbags and coarse rock was placed over the exposed pipe segment. Continued pipe elevation monitoring and annual Geopig surveys have indicated that both seasonal heave/settlement and strains have been reduced subsequent to the remedial loading. Introduction of a gravel berm has also altered both the surrounding hydrologic and ground thermal regimes.

scholarly journals Influence of a single lightning discharge on the intensity of an air electric field and acoustic emission of near-surface rocks

Solid Earth ◽  
2012 ◽  
Vol 3 (2) ◽  
pp. 307-311 ◽  
Author(s):  
S. E. Smirnov ◽  
Y. V. Marapulets
Keyword(s):  
Acoustic Emission ◽  
Electric Field ◽  
Normal Level ◽  
Electric Potential ◽  
Characteristic Time ◽  
Lightning Discharge ◽  
Potential Gradient ◽  
Capacitor Discharge ◽  
Near Surface ◽  
Sharp Fall

Abstract. The effect was observed as a sharp fall of the electric potential gradient from +80 V m−1 down to –21 V m−1. After that the field returned to its normal level according to the formula of the capacitor discharge with 17 s characteristic time. Simultaneously, the response of the acoustic emission of surface rocks in the range of frequencies between 6.5 kHz and 11 kHz was evaluated.

Surface Seismic Measurements of Near-Surface P- and S-Wave Seismic Velocities at Earthquake Recording Stations, Seattle, Washington

1999 ◽  
Vol 15 (3) ◽  
pp. 565-584 ◽  
Author(s):  
Robert A. Williams ◽  
William J. Stephenson ◽  
Arthur D. Frankel ◽  
Jack K. Odum
Keyword(s):  
Seismic Refraction ◽  
Ground Surface ◽  
Industrial Area ◽  
High Amplitude ◽  
Seismic Velocities ◽  
S Wave ◽  
Near Surface ◽  
Sedimentary Deposits ◽  
Reflection Data ◽  
Seismic Reflections

We measured P- and S-wave seismic velocities to about 40-m depth using seismic-refraction/reflection data on the ground surface at 13 sites in the Seattle, Washington, urban area, where portable digital seismographs recently recorded earthquakes. Sites with the lowest measured Vs correlate with highest ground motion amplification. These sites, such as at Harbor Island and in the Duwamish River industrial area (DRIA) south of the Kingdome, have an average Vs in the upper 30 m (V¯s30) of 150 to 170 m/s. These values of V¯s30 place these sites in soil profile type E (V¯s30 < 180 m/s). A “rock” site, located at Seward Park on Tertiary sedimentary deposits, has a V¯s30 of 433 m/s, which is soil type C (V¯s30: 360 to 760 m/s). The Seward Park site V¯s30 is about equal to, or up to 200 m/s slower than sites that were located on till or glacial outwash. High-amplitude P- and S-wave seismic reflections at several locations appear to correspond to strong resonances observed in earthquake spectra. An S-wave reflector at the Kingdome at about 17 to 22 m depth probably causes strong 2-Hz resonance that is observed in the earthquake data near the Kingdome.

Theoretical and experimental examinations of the capacitively coupled resistivity (line antenna) method

Geophysics ◽  
2013 ◽  
Vol 78 (4) ◽  
pp. E189-E199 ◽  
Author(s):  
Qifei Niu ◽  
Yu-Hsing Wang
Keyword(s):  
Ground Surface ◽  
Antenna System ◽  
Geometric Factor ◽  
Gap Effect ◽  
Geometrical Factor ◽  
Measurement Bias ◽  
Current Frequency ◽  
Near Surface ◽  
Capacitively Coupled ◽  
Gap Height

The capacitively coupled (CC) resistivity method is an emerging geophysical technique for near-surface investigations. However, there are two major problems associated with using the CC resistivity (line antenna) system in ground investigations. These two problems are (1) the geometrical factor and (2) measurement biases. We first derive the geometric factor for the line-antenna array in a dipole-dipole configuration. The new expression of the geometric factor considers the separation between the two current (and the two potential) line antennas, thereby improving the accuracy of the measured apparent resistivity. Second, from the electroquasistatic point of view, a quadruline model that can describe the characteristics of the CC resistivity (line antenna) system is derived based on the previously published quadrupole model. The validity of the quadruline model is verified experimentally. Based on the quadruline model, it is found that the dielectric properties of the line-to-ground capacitor and the ground permittivity produce measurement bias at low and high current frequencies, respectively. If the operating current frequency is around the kHz range and the ground resistivity is relatively high, such as in permafrost areas, the ground permittivity can also create measurement bias to cause the actual value to be underestimated. The experimental results and the predictions by the quadruline model suggest that the measurement bias induced by the gap between the line antenna and the ground surface becomes significant and cannot be ignored as the gap height is large and the associated ground resistivity is low. In general, the CC resistivity (line antenna) measurements are not biased by the gap effect when the gap height is less than 0.01 m, which can easily be achieved for tests on flat ground.

Effects of terrain on borehole gravity data

Geophysics ◽  
1980 ◽  
Vol 45 (2) ◽  
pp. 234-243 ◽  
Author(s):  
J. R Hearst ◽  
J. W. Schmoker ◽  
R. C. Carlson
Keyword(s):  
Gravity Data ◽  
Radial Distance ◽  
Ground Surface ◽  
Absolute Maximum ◽  
Near Surface ◽  
Free Air ◽  
Gravity Measurements ◽  
Terrain Elevation ◽  
Lower Magnitude ◽  
Terrain Features

The effect of terrain on gravity measurements in a borehole and on formation density derived from borehole gravity data is studied as a function of depth in the well, terrain elevation, terrain inclination, and radial distance to the terrain feature. The vertical attraction of gravity [Formula: see text] in a borehole resulting from a terrain element is small at the surface and reaches an absolute maximum at a depth of about one and one‐half times the radial distance to the terrain element, then decreases at greater depths. The effect of terrain on calculated formation density is proportional to the vertical derivative of [Formula: see text] and is maximum at the surface, passes through zero where |[Formula: see text]| is greatest, and reaches a second extremum of opposite sign to the first and of much lower magnitude. Accuracy criteria for borehole‐gravity terrain corrections show that elevation accuracy requirements are most stringent for a combination of nearby terrain features and near‐surface gravity stations. Sensitivity to terrain inclination is also greatest for this combination. The measurement of the free‐air gradient of gravity, commonly made’slightly above the ground surface, is extremely sensitive to topographic irregularities within about 300m of the measurement point. The effect of terrain features 21.9 to 166.7 km from the well [Hammer’s (1939) zone M through Hayford‐Bowie’s (1912) zone O] on calculated formation density is nearly constant with depth. At these distances, the terrain correction will be equivalent to a dc shift of about [Formula: see text] of average elevation above or below the correction datum. The effect of topography beyond 166.7 km is not likely to exceed [Formula: see text].

Microscale Mechanical Behavior of the Subsurface by Finishing Processes

2005 ◽  
Vol 127 (2) ◽  
pp. 333-338 ◽  
Author(s):  
Y. B. Guo ◽  
A. W. Warren
Keyword(s):  
Mechanical Behavior ◽  
Hard Turning ◽  
White Layer ◽  
Subsurface Layer ◽  
Ground Surface ◽  
Small Scale ◽  
Near Surface ◽  
Microstructure Changes ◽  
Shallow Layer ◽  
Finishing Processes

Hard turning, grinding, and honing are common finishing processes in today’s production. The machined subsurface undergoes severe deformation and possible microstructure changes in a small scale subsurface layer <20μm. Mechanical behavior of this shallow layer is critical for component performance such as fatigue and wear. Due to the small size of this region, mechanical behavior of this shallow layer is hard to measure using traditional material testing. With the nanoindentation method, mechanical behavior (nanohardness and modulus) at the microscale in subsurface was measured for AISI 52100 and AISI 1070 steel components machined by hard turning, grinding, and honing. The test results show that white layer increases nanohardness but decreases modulus of a turned surface. Nanohardness and modulus of the ground surface are slightly smaller than the honed one in the subsurface. However, grinding produces higher nanohardness and modulus in near-surface <10μm than honing, while honing produces more uniform hardness and modulus in the near-surface and subsurface, and would improve component performance. Nanohardness and modulus of the machined near-surface are strongly influenced by strain hardening, residual stress, size-effect, and microstructure changes.

scholarly journals Ground surface-temperature reconstruction based on data from a deep borehole in permafrost at Janssonhaugen, Svalbard

2000 ◽  
Vol 31 ◽  
pp. 287-294 ◽  
Author(s):  
Ketil Isaksen ◽  
Daniel Vonder Mühll ◽  
Hansueli Gubler ◽  
Thomas Kohl ◽  
Johan Ludvig Sollid
Keyword(s):  
Surface Temperature ◽  
Phase Speed ◽  
Ground Surface ◽  
Temperature Reconstruction ◽  
Geothermal Gradient ◽  
Temperature History ◽  
Deep Borehole ◽  
Near Surface ◽  
Ground Surface Temperature ◽  
Average Value

AbstractAnalyses of the geothermal gradient in permafrost areas constitute a key signal of the ground-surface temperature history. Permafrost temperatures in selected areas are particularly well suited to reconstructing past surface-temperature changes, mainly because there is no thermal disturbance due to circulating groundwater. One year of temperature data from an instrumented 102 m deep borehole in permafrost on Janssonhaugen, Svalbard, is presented. Ground thermal properties are calculated. The average value for the thermal conductivity is 1.85 ±0.05 W m–1 K–1 , and the average value for the thermal diffusivity is 1.1m2 s–1, which gives a phase speed for the annual wave of 5.65 × KT2 m d–1. The depth of zero annual amplitude is 18 m The permafrost thickness is estimated as approximately 220 m. Analysis of the temperatures reveals an increasing temperature gradient with depth. Using a heat-conduction inversion model, a palaeoclimatic reconstruction is presented, showing a warming of the surface temperature over the last 60–80 years. The temperature profile represents a regional signal on Svalbard, which shows an inflection associated with near-surface warming of 1.5 ± 0.5°C in the 20th century.

Sign in / Sign up

Export Citation Format

Share Document