Some Observations on the Depth Range and Size of Devil Firefish Pterois miles (Bennett, 1828) (Scorpaenidae) in Silifke Mersin (Turkey)

AbstractThe pile up patterns arising in nanoindentation are shown to be indicative of the sample crystal symmetry. To explain and interpret these patterns, complementary molecular dynamics simulations and experiments have been performed to determine the atomistic mechanisms of the nanoindentation process in single crystal Fe{110}. The simulations show that dislocation loops start from the tip and end on the crystal surface propagating outwards along the four in-plane <111> directions. These loops carry material away from the indenter and form bumps on the surface along these directions separated from the piled-up material around the indenter hole. Atoms also move in the two out-of-plane <111> directions causing propagation of subsurface defects and pile-up around the hole. This finding is confirmed by scanning force microscopy mapping of the imprint, the piling-up pattern proving a suitable indicator of the surface crystallography. Experimental force-depth curves over the depth range of a few nanometers do not appear smooth and show distinct pop-ins. On the sub-nanometer scale these pop-ins are also visible in the simulation curves and occur as a result of the initiation of the dislocation loops from the tip.

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GEOPHYSICAL AND WATER QUALITY INDEX SURVEYS OF GROUNDWATER QUALITY AROUND UGBOR DUMPSITE IN BENIN CITY, EDO STATE, NIGERIA, WEST AFRICA.

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v12i3.43 ◽

2016 ◽

Vol 12 (3) ◽

pp. 4383-4393

Author(s):

Osabuohien Idehen

Keyword(s):

Water Quality ◽

Groundwater Quality ◽

Water Quality Index ◽

Quality Index ◽

Dry Season ◽

Depth Range ◽

Benin City ◽

Physico Chemical ◽

Vertical Electric Sounding ◽

Geoelectric Layer

This study takes a look into groundwater quality at Ugbor Dumpsite area using water quality index (WQI), 2-Dimensional (2-D) geophysical resistivity tomography and vertical electric sounding (VES).The geophysical resistivity methods employed revealed the depth to aquifer, the geoelectric layers being made up of lateritic topsoil, clayed sand and sand. Along the trasverse line in the third geoelectric layer of lateral distance of 76 m to 100 m is a very low resistivity of 0.9 to 13 m from a depth range o f about 3 to 25 m beneath the surface- indicating contamination. Water samples were collected and analyzed at the same site during the raining season and during the dry season. The value of water quality index during the raining season was 115.92 and during the dry season was 147.43. Since values at both seasons were more than 100, it implies that the water is contaminated to some extent and therefore poor for drinking purpose. The Water Quality Index was established from important analyses of biological and physico-chemical parameters with significant health importance. These values computed for dumpsite area at Ugbor were mostly contributed by the seasonal variations in the concentrations of some parameters, such as, conductivity, total dissolved solids, hardness, alkalinity, chlorides, nitrates, calcium,Â phosphates, zinc, which showed significant differences (P<0.01 and P<0.05) in seasonal variation.

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Depth Range Control in Visually Equivallent Light Field 3D (VELF3D) Display

Proceedings of the International Display Workshops ◽

10.36463/idw.2019.0065 ◽

2019 ◽

pp. 65

Author(s):

Munekazu Date ◽

Shinya Shimizu ◽

Hideaki Kimata

Keyword(s):

Light Field ◽

Depth Range

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Determination of Lead in Soils Surrounding a Lead-Acid Battery Manufacturer

Water Quality Research Journal ◽

10.2166/wqrj.1995.028 ◽

1995 ◽

Vol 30 (2) ◽

pp. 299-304 ◽

Cited By ~ 4

Author(s):

Cameron D. Skinner ◽

Eric D. Salin

Keyword(s):

Lead Concentration ◽

Depth Range ◽

Lead Acid Battery ◽

Soil Lead ◽

Lead Levels ◽

Factory Site ◽

Lead Acid

Abstract Soil lead levels were determined on and around a former battery manufacturing site. Lead concentrations ranging from 120 ppm to 5.1’ were found. The highest concentrations were found close to the factory site. When it was possible to obtain samples over a continuous depth range, it was found that lead concentration decreased with depth and that it increased above underground foundations.

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Seagrass depth range and water quality in southern Moreton Bay, Queensland, Australia

Marine and Freshwater Research ◽

10.1071/mf9960763 ◽

1996 ◽

Vol 47 (6) ◽

pp. 763 ◽

Cited By ~ 95

Author(s):

EG Abal ◽

WC Dennison

Keyword(s):

Water Quality ◽

Chlorophyll A ◽

Suspended Solids ◽

Light Attenuation ◽

River Mouth ◽

Total Suspended Solids ◽

Quality Parameters ◽

Depth Range ◽

Moreton Bay ◽

A Site

Correlations between water quality parameters and seagrass depth penetration were developed for use as a biological indicator of integrated light availability and long-term trends in water quality. A year-long water quality monitoring programme in Moreton Bay was coupled with a series of seagrass depth transects. A strong gradient between the western (landward) and eastern (seaward) portions of Moreton Bay was observed in both water quality and seagrass depth range. Higher concentrations of chlorophyll a, total suspended solids, dissolved and total nutrients, and light attenuation coefficients in the water column and correspondingly shallower depth limits of the seagrass Zostera capricorni were observed in the western portions of the bay. Relatively high correlation coefficient values (r2 > 0.8) were observed between light attenuation coefficient, total suspended solids, chlorophyll a, total Kjeldahl nitrogen and Zostera capricorni depth range. Low correlation coefficient values (r2 < 0.8) between seagrass depth range and dissolved inorganic nutrients were observed. Seagrasses had disappeared over a five-year period near the mouth of the Logan River, a turbid river with increased land use in its watershed. At a site 9 km from the river mouth, a significant decrease in seagrass depth range corresponded to higher light attenuation, chlorophyll a, total suspended solids and total nitrogen content relative to a site 21 km from the river mouth. Seagrass depth penetration thus appears to be a sensitive bio-indicator of some water quality parameters, with application for water quality management.

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Ground-motion model for subduction earthquakes in northern South America

Earthquake Spectra ◽

10.1177/87552930211027585 ◽

2021 ◽

pp. 875529302110275

Author(s):

Carlos A Arteta ◽

Cesar A Pajaro ◽

Vicente Mercado ◽

Julián Montejo ◽

Mónica Arcila ◽

...

Keyword(s):

South America ◽

Ground Motion ◽

Ground Motions ◽

Strong Motion ◽

Motion Prediction ◽

Depth Range ◽

Ground Motion Prediction ◽

Natural Period ◽

Nazca Plate ◽

Northern South America

Subduction ground motions in northern South America are about a factor of 2 smaller than the ground motions for similar events in other regions. Nevertheless, historical and recent large-interface and intermediate-depth slab earthquakes of moment magnitudes Mw = 7.8 (Ecuador, 2016) and 7.2 (Colombia, 2012) evidenced the vast potential damage that vulnerable populations close to earthquake epicenters could experience. This article proposes a new empirical ground-motion prediction model for subduction events in northern South America, a regionalization of the global AG2020 ground-motion prediction equations. An updated ground-motion database curated by the Colombian Geological Survey is employed. It comprises recordings from earthquakes associated with the subduction of the Nazca plate gathered by the National Strong Motion Network in Colombia and by the Institute of Geophysics at Escuela Politécnica Nacional in Ecuador. The regional terms of our model are estimated with 539 records from 60 subduction events in Colombia and Ecuador with epicenters in the range of −0.6° to 7.6°N and 75.5° to 79.6°W, with Mw≥4.5, hypocentral depth range of 4 ≤ Zhypo ≤ 210 km, for distances up to 350 km. The model includes forearc and backarc terms to account for larger attenuation at backarc sites for slab events and site categorization based on natural period. The proposed model corrects the median AG2020 global model to better account for the larger attenuation of local ground motions and includes a partially non-ergodic variance model.

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Experimental Study on the Thickness-Dependent Hardness of SiO2 Thin Films Using Nanoindentation

Coatings ◽

10.3390/coatings11010023 ◽

2020 ◽

Vol 11 (1) ◽

pp. 23

Author(s):

Weiguang Zhang ◽

Jijun Li ◽

Yongming Xing ◽

Xiaomeng Nie ◽

Fengchao Lang ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Grain Size ◽

Integrated Circuits ◽

Film Thickness ◽

Depth Range ◽

Micro Electro Mechanical Systems ◽

Si Substrates ◽

Sio2 Thin Film ◽

Average Grain Size

SiO2 thin films are widely used in micro-electro-mechanical systems, integrated circuits and optical thin film devices. Tremendous efforts have been devoted to studying the preparation technology and optical properties of SiO2 thin films, but little attention has been paid to their mechanical properties. Herein, the surface morphology of the 500-nm-thick, 1000-nm-thick and 2000-nm-thick SiO2 thin films on the Si substrates was observed by atomic force microscopy. The hardnesses of the three SiO2 thin films with different thicknesses were investigated by nanoindentation technique, and the dependence of the hardness of the SiO2 thin film with its thickness was analyzed. The results showed that the average grain size of SiO2 thin film increased with increasing film thickness. For the three SiO2 thin films with different thicknesses, the same relative penetration depth range of ~0.4–0.5 existed, above which the intrinsic hardness without substrate influence can be determined. The average intrinsic hardness of the SiO2 thin film decreased with the increasing film thickness and average grain size, which showed the similar trend with the Hall-Petch type relationship.

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An automatically generated high-resolution earthquake catalogue for the 2016–2017 Central Italy seismic sequence, including P and S phase arrival times

Geophysical Journal International ◽

10.1093/gji/ggaa604 ◽

2020 ◽

Author(s):

D Spallarossa ◽

M Cattaneo ◽

D Scafidi ◽

M Michele ◽

L Chiaraluce ◽

...

Keyword(s):

Real Time ◽

Central Italy ◽

Earthquake Catalogue ◽

Hazard Evaluation ◽

Depth Range ◽

Data Set ◽

Epicentral Area ◽

Earthquake Parameters ◽

Waveform Data ◽

Arrival Times

Summary The 2016–17 central Italy earthquake sequence began with the first mainshock near the town of Amatrice on August 24 (MW 6.0), and was followed by two subsequent large events near Visso on October 26 (MW 5.9) and Norcia on October 30 (MW 6.5), plus a cluster of 4 events with MW > 5.0 within few hours on January 18, 2017. The affected area had been monitored before the sequence started by the permanent Italian National Seismic Network (RSNC), and was enhanced during the sequence by temporary stations deployed by the National Institute of Geophysics and Volcanology and the British Geological Survey. By the middle of September, there was a dense network of 155 stations, with a mean separation in the epicentral area of 6–10 km, comparable to the most likely earthquake depth range in the region. This network configuration was kept stable for an entire year, producing 2.5 TB of continuous waveform recordings. Here we describe how this data was used to develop a large and comprehensive earthquake catalogue using the Complete Automatic Seismic Processor (CASP) procedure. This procedure detected more than 450,000 events in the year following the first mainshock, and determined their phase arrival times through an advanced picker engine (RSNI-Picker2), producing a set of about 7 million P- and 10 million S-wave arrival times. These were then used to locate the events using a non-linear location (NLL) algorithm, a 1D velocity model calibrated for the area, and station corrections and then to compute their local magnitudes (ML). The procedure was validated by comparison of the derived data for phase picks and earthquake parameters with a handpicked reference catalogue (hereinafter referred to as ‘RefCat’). The automated procedure takes less than 12 hours on an Intel Core-i7 workstation to analyse the primary waveform data and to detect and locate 3000 events on the most seismically active day of the sequence. This proves the concept that the CASP algorithm can provide effectively real-time data for input into daily operational earthquake forecasts, The results show that there have been significant improvements compared to RefCat obtained in the same period using manual phase picks. The number of detected and located events is higher (from 84,401 to 450,000), the magnitude of completeness is lower (from ML 1.4 to 0.6), and also the number of phase picks is greater with an average number of 72 picked arrival for a ML = 1.4 compared with 30 phases for RefCat using manual phase picking. These propagate into formal uncertainties of ± 0.9km in epicentral location and ± 1.5km in depth for the enhanced catalogue for the vast majority of the events. Together, these provide a significant improvement in the resolution of fine structures such as local planar structures and clusters, in particular the identification of shallow events occurring in parts of the crust previously thought to be inactive. The lower completeness magnitude provides a rich data set for development and testing of analysis techniques of seismic sequences evolution, including real-time, operational monitoring of b-value, time-dependent hazard evaluation and aftershock forecasting.

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The relationship between Vs, Vp, density and depth based on PS-logging data at K-NET and KiK-net sites

Geophysical Journal International ◽

10.1093/gji/ggab037 ◽

2021 ◽

Author(s):

Fumiaki Nagashima ◽

Hiroshi Kawase

Keyword(s):

Standard Deviation ◽

Seismic Velocity ◽

Saturated Soil ◽

P Wave ◽

Soil Types ◽

Depth Range ◽

Velocity Inversion ◽

Velocity Models ◽

Regression Curves ◽

Ps Logging

Summary P-wave velocity (Vp) is an important parameter for constructing seismic velocity models of the subsurface structures by using microtremors and earthquake ground motions or any other geophysical exploration data. In order to reflect the ground survey information in Japan to the Vp structure, we investigated the relationships among Vs, Vp, and depth by using PS-logging data at all K-NET and KiK-net sites. Vp values are concentrated at around 500 m/s and 1,500 m/s when Vs is lower than 1,000 m/s, where these concentrated areas show two distinctive characteristics of unsaturated and saturated soil, respectively. Many Vp values in the layer shallower than 4 m are around 500 m/s, which suggests the dominance of unsaturated soil, while many Vp values in the layer deeper than 4 m are larger than 1,500 m/s, which suggests the dominance of saturated soil there. We also investigated those relationships for different soil types at K-NET sites. Although each soil type has its own depth range, all soil types show similar relationships among Vs, Vp, and depth. Then, considering the depth profile of Vp, we divided the dataset into two by the depth, which is shallower or deeper than 4 m, and calculated the geometrical mean of Vp and the geometrical standard deviation in every Vs bins of 200 m/s. Finally, we obtained the regression curves for the average and standard deviation of Vp estimated from Vs to get the Vp conversion functions from Vs, which can be applied to a wide Vs range. We also obtained the regression curves for two datasets with Vp lower and higher than 1,200 m/s. These regression curves can be applied when the groundwater level is known. In addition, we obtained the regression curves for density from Vs or Vp. An example of the application for those relationships in the velocity inversion is shown.

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The influence of dynamic environmental interactions on detection efficiency of acoustic transmitters in a large, deep, freshwater lake

Animal Biotelemetry ◽

10.1186/s40317-019-0179-1 ◽

2019 ◽

Vol 7 (1) ◽

Cited By ~ 3

Author(s):

Natalie V. Klinard ◽

Edmund A. Halfyard ◽

Jordan K. Matley ◽

Aaron T. Fisk ◽

Timothy B. Johnson

Keyword(s):

Study Design ◽

Environmental Conditions ◽

Power Output ◽

Environmental Variables ◽

Acoustic Telemetry ◽

Detection Efficiency ◽

Data Interpretation ◽

Heterogeneous Environments ◽

Depth Range ◽

Dynamic Relationship

Abstract Background Acoustic telemetry is an increasingly common method used to address ecological questions about the movement, behaviour, and survival of freshwater and marine organisms. The variable performance of acoustic telemetry equipment and ability of receivers to detect signals from transmitters have been well studied in marine and coral reef environments to inform study design and improve data interpretation. Despite the growing use of acoustic telemetry in large, deep, freshwater systems, detection efficiency and range, particularly in relation to environmental variation, are poorly understood. We used an array of 90 69-kHz acoustic receivers and 8 sentinel range transmitters of varying power output deployed at different depths and locations approximately 100–9500 m apart for 215 days to evaluate how the detection efficiency of acoustic receivers varied spatially and temporally in relation to environmental conditions. Results The maximum distance that tags were detected ranged from 5.9 to 9.3 km. Shallow tags consistently had lower detection efficiency than deep tags of the same power output and detection efficiency declined through the winter months (December–February) of the study. In addition to the distance between tag and receiver, thermocline strength, surface water velocity, ice thickness, water temperature, depth range between tag and receiver, and number of fish detections contributed to explaining variation in detection efficiency throughout the study period. Furthermore, the most significant models incorporated interactions between several environmental variables and tag–receiver distance, demonstrating the complex temporal and spatial relationships that exist in heterogeneous environments. Conclusions Relying on individual environmental variables in isolation to interpret receiver performance, and thus animal behaviour, may be erroneous when detection efficiency varies across distances, depths, or tag types. As acoustic telemetry becomes more widely used to study ecology and inform management, it is crucial to understand its limitations in heterogeneous environments, such as freshwater lakes, to improve the quality and interpretation of data. We recommend that in situ range testing and retrospective analysis of detection efficiency be incorporated into study design for telemetry projects. Furthermore, we caution against oversimplifying the dynamic relationship between detection efficiency and environmental conditions for the sake of producing a correction that can be applied directly to detection data of tagged animals when the intended correction may not be justified.

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