scholarly journals A new empirical equation for predicting the maximum initial amplitude of submarine landslide-generated waves

Landslides ◽  
2021 ◽  
Author(s):  
Ramtin Sabeti ◽  
Mohammad Heidarzadeh
Keyword(s):  
Field Data ◽  
Empirical Equation ◽  
Laboratory Data ◽  
Slope Angle ◽  
Physical Modelling ◽  
Empirical Equations ◽  
Submarine Landslides ◽  
Landslide Volume ◽  
Landslide Tsunami ◽  
Tsunami Amplitude

AbstractThe accurate prediction of landslide tsunami amplitudes has been a challenging task given large uncertainties associated with landslide parameters and often the lack of enough information of geological and rheological characteristics. In this context, physical modelling and empirical equations have been instrumental in developing landslide tsunami science and engineering. This study is focused on developing a new empirical equation for estimating the maximum initial landslide tsunami amplitude for solid-block submarine mass movements. We are motivated by the fact that the predictions made by existing equations were divided by a few orders of magnitude (10−1–104 m). Here, we restrict ourselves to three main landslide parameters while deriving the new predictive equation: initial submergence depth, landslide volume and slope angle. Both laboratory and field data are used to derive the new empirical equation. As existing laboratory data was not comprehensive, we conduct laboratory experiments to produce new data. By applying the genetic algorithm approach and considering non-dimensional parameters, we develop and examine 14 empirical equations for the non-dimensional form of the maximum initial tsunami amplitude. The normalized root mean square error (NRMSE) index between observations and calculations is used to choose the best equation. Our proposed empirical equation successfully reproduces both laboratory and field data. This equation can be used to provide a preliminary and rapid estimate of the potential hazards associated with submarine landslides using limited landslide parameters.

scholarly journals A numerical study of submarine–landslide–generated tsunami and its propagation in Majene, West Sulawesi

2021 ◽  
Vol 925 (1) ◽  
pp. 012035
Author(s):  
H Khoirunnisa ◽  
S Karima ◽  
G Gumbira ◽  
R A Rachman
Keyword(s):  
Wave Propagation ◽  
Tsunami Wave ◽  
Numerical Study ◽  
Slope Angle ◽  
Wave Model ◽  
Submarine Landslide ◽  
Submarine Landslides ◽  
Tsunami Propagation ◽  
Tsunami Modelling ◽  
Landslide Volume

Abstract On 14th January 2021, there was a devastating earthquake (Mw 6.2) hit Mamuju and Majene, West Sulawesi, Indonesia at 18.28 UTC. According to National Disaster Management Authority, this event causes 84 casualties and 279 houses were damaged. The Sulawesi Island is situated in a very complex tectonic region, there are several thrusts and faults along the area such as Majene Thrust, Palu-Karo Thrust, Matano Fault, and Tolo Thrust that can lead to tectonic activities. One of the largest earthquakes was a 7.9 Mw in 1997 generated from North Sulawesi Megathrust that caused a catastrophic tsunami. Moreover, there were 9 tsunami events in the Makassar Strait from the year 1800 to 1999. In this research, three different scenarios of the tsunami in Majene were applied to obtain the tsunami elevation. Makassar Strait could be potentially generated tsunami wave from submarine landslides due to its steep bathymetry that will impact the coastline at Sulawesi and Kalimantan, so it is necessary to model the tsunami propagation using submarine landslide as the tsunami generation. The volume of submarine landslide had been used in tsunami submarine landslide modelling as an input. Those are included the height, width and length of the submarine landslide volume. Furthermore, the domain bathymetry was obtained from National Bathymetry (BatNas) with spacing grid of 300 m × 300 m. The submarine landslide coordinate is also needed as a source of tsunami at 2.98°S and 118.94°E. The slide angle and slope angle are also inputted in this modelling with three experimental volumes, namely 1 km3, 0.8 km3, and 0.5 km3. This submarine landslide tsunami modelling used the Non-Hydrostatic WAVE Model (NHWAVE) method to obtain tsunami wave generation. The result from NHWAVE model will be used for initial elevation of tsunami wave propagation using the Fully Nonlinear Boussinesq wave model - Total Variation Diminishing (FUNWAVE - TVD) method. The highest initial tsunami elevation value at each observation point obtained from the NHWAVE model occurred at point 18 (the closest location to the earthquake source), which is around 0.4 –1.2 m. The FUNWAVE simulation result is the tsunami wave propagation for 180 minutes later. In the 180th minute, the tsunami wave was still propagating towards the north of Sulawesi Island to the east of Kalimantan Island.

Porcellio spinicornis Say (Isopoda) demography. II. A comparison between field and laboratory data

1976 ◽  
Vol 54 (6) ◽  
pp. 825-842 ◽  
Author(s):  
Donald J. McQueen
Keyword(s):  
Field Data ◽  
Laboratory Data ◽  
Field Population ◽  
Laboratory Studies ◽  
The Third ◽  
Terrestrial Isopod ◽  
Independent Laboratory ◽  
Demographic Study ◽  
June July ◽  
Rates Of Growth

Field data from a demographic study of the terrestrial isopod Porcellio spinicornis Say were analyzed and compared with laboratory data reported by McQueen and Carnio. On the study area, which covered 482.8 m2, it was observed that reproduction began when average temperatures were > 13 °C, and that about 86% of the individuals produced one brood and about 30% produced two broods. During 1972, 25 654 offspring were produced and during 1973, 27 664 offspring resulted from reproduction, which took place during May, June, July, and August. By October of both years, these animals attained sizes ranging from 10 to 30 mg and exhibited 42 to 47% survivorship. During the next summer, females grew to between 30 and 50 mg and males to between 20 and 40 mg, and survivorship ranged from 15% in May to 2% in August. During the third summer, females attained sizes ranging from 80 to 100 mg and males from 40 to 70 mg. Survivorship during this period ranged from 1% in May to 0% in August. All rates of growth, reproduction, and survival, as well as reproductive periodicity, agreed with independent laboratory studies conducted under controlled conditions. During the 3 years studied the field population remained relatively constant and appeared to be limited by temperature conditions.

NUMERICAL AND PHYSICAL MODELLING OF KAOLIN AS BACKFILL MATERIAL FOR POLYMER CONCRETE RETAINING WALL

2015 ◽  
Vol 76 (2) ◽  
Author(s):  
Ali Arefnia ◽  
Khairul Anuar Kassim ◽  
Houman Sohaei ◽  
Kamarudin Ahmad ◽  
Ahmad Safuan A Rashid
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Numerical Analysis ◽  
Retaining Wall ◽  
Laboratory Data ◽  
Physical Modelling ◽  
Horizontal Displacement ◽  
Polymer Concrete ◽  
The Finite Element Method ◽  
Backfill Material

 The failure mechanism of backfill material for retaining wall was studied by performing a numerical analysis using the finite element method. Kaolin is used as backfill material and retaining wall is constructed by Polymer Concrete. The laboratory data of an instrumented cantilever retaining wall are reexamined to confirm an experimental working hypothesis. The obtained laboratory data are the backfill settlement and horizontal displacement of the wall. The observed response demonstrates the backfill settlement and displacement of the retaining wall from the start to completion of loading. In conclusion, numerical modelling results based on computer programming by ABAQUS confirms the experimental results of the physical modelling.  

scholarly journals New correlations for predicting two-phase electrical submersible pump performance under downhole conditions using field data

2021 ◽  
Author(s):  
Thuy Chu ◽  
Tan C. Nguyen ◽  
Jihoon Wang ◽  
Duc Vuong
Keyword(s):  
Experimental Data ◽  
Field Data ◽  
Laboratory Data ◽  
Performance Curve ◽  
Submersible Pump ◽  
Two Phase ◽  
Experimental Conditions ◽  
Pump Performance ◽  
Free Gas ◽  
Electrical Submersible Pump

AbstractElectrical Submersible Pump (ESP) is one of the major Artificial Lift methods that is reliable and effective for pumping high volume of fluids from wellbores. However, ESP is not recommended for applications with high gas liquid ratio. The presence of free gas inside the pump causes pump performance degradation which may lead to problems or even failure during operations. Thus, it is important to investigate effect of free gas on ESP performance under downhole conditions. At present, existing models or correlations are based on/verified with experimental data. This study is one of the first attempts to develop correlations for predicting two-phase gas–liquid pump performance under downhole conditions by using field data and laboratory data. Field data from three oil producing wells provided by Strata Production Company and Perdure Petroleum LLC. as well as experimental data obtained from experimental facility at Production and Drilling Research Project—New Mexico Tech were used in this study. Actual two-phase pump differential pressure per stage is obtained from experiments or estimated from field data and was normalized using pump performance curve. The values are compared to pump performance curve to study the relationships between pump performance and free gas percentage at pump intake. Correlations to predict ESP performance in two-phase flow under downhole and experimental conditions was derived from the results using regression technique. The correlation developed from field data presented in this study can be used to predict two-phase ESP performance under downhole conditions and under high gas fraction. The results from the experimental data confirm the reliability of the developed correlation using field data to predict two-phase ESP performance under downhole conditions. The developed correlation using the laboratory data predicts quite well the two-phase pump performance at the gas fraction of less than 15% while it is no longer reliable when free gas fraction is more than 15%. The findings from this study will help operating companies as well as ESP manufacturers to operate ESPs within the recommended range under downhole conditions. However, it is recommended to use the proposed correlation on reservoirs with conditions similar to those of the three presented wells.

ANALYSIS FOR HYDROCARBONS IN THE PRESENCE OF NITROUS OXIDE

Geophysics ◽  
1944 ◽  
Vol 9 (4) ◽  
pp. 447-462 ◽  
Author(s):  
Monroe W. Kriegel
Keyword(s):  
Nitrous Oxide ◽  
Field Data ◽  
Laboratory Data ◽  
Saturated Hydrocarbons ◽  
Soil Air ◽  
Hydrocarbon Content ◽  
True Measure

The technique for the analysis of soil air for small quantities of hydrocarbons is reviewed. Various methods of expressing results and the basis for the calculation of each are given. Field data on expansion ratios are presented to show that there exists in the soil air a gas, other than the saturated hydrocarbons, which is not removed by the screening agents and is retained in the condensation trap. The reasons for believing that this gas is nitrous oxide are given, together with plausible sources of this gas in the soil air. Laboratory data are presented on the analysis of pure hydrocarbons in the presence and in the absence of this gas. Calculations made by each of the methods show that when results are based on after‐burning readings, a true measure of the hydrocarbon content is evolved, regardless of the presence of nitrous oxide.

Porcellio spinicornis Say (Isopoda) demography. III. A comparison between field data and the results of a simulation model

1976 ◽  
Vol 54 (12) ◽  
pp. 2174-2184 ◽  
Author(s):  
Donald James McQueen
Keyword(s):  
Population Growth ◽  
Simulation Model ◽  
Field Data ◽  
Survival Rates ◽  
Laboratory Data ◽  
Individual Growth ◽  
Growth And Survival ◽  
Life History Stages ◽  
Demographic Rates ◽  
Rates Of Growth

A simulation model for a Porcellio spinicornis Say population was constructed using laboratory data for rates of growth, reproduction, and survival and using winter survival rates observed in the field. The simulated output was compared with field data collected from 1971 to 1973. The expected and observed weight distributions and reproductive periodicities showed good agreement. The expected and observed patterns of numerical change also agreed for all life-history stages, except 18-month-old individuals, which disappeared from the field counts more quickly than expected. Sensitivity analysis showed that the time at which reproduction began each year was not as critical to population growth as were the effects of minor shifts in temperature on individual growth and survival rates. Furthermore, individual growth rate emerged as the factor having the greatest effect on patterns of population growth. Since the laboratory data on growth was reasonably accurate it is probable that the simulation model adequately describes the processes that determine the changes observed in the field population monitored during this study. All of the evidence indicated that during the period of study the population did not increase or decrease and that temperature conditions modifying demographic rates could have accounted for this observation.

The influence of climatic factors on the demography of the terrestrial isopod Tracheoniscus rathkei Brandt

1976 ◽  
Vol 54 (12) ◽  
pp. 2185-2199 ◽  
Author(s):  
Donald J. McQueen
Keyword(s):  
Life Cycle ◽  
Simulation Model ◽  
Field Data ◽  
Climatic Factors ◽  
Laboratory Data ◽  
Day Length ◽  
Model Output ◽  
Population Limitation ◽  
Growth And Survival ◽  
Rates Of Growth

A field population of the isopod Tracheoniscus rathkei was monitored during 1971, 1972, and 1973. At the same time, laboratory data related to growth, reproduction, and survival were collected and combined to produce a simulation model. The model output was compared with the field data. In the laboratory, T. rathkei required humidities very near 100% relative humidity, day length had no effect on growth rates, and temperature altered rates of growth and survival and determined the periodicity of reproduction. In the field, T. rathkei exhibited a 2-year life cycle, breeding occurred in the spring and summer, and about 83% of the population bred once and 42% bred twice during each year. Juveniles grew throughout the fall, overwintered, reproduced at 1 year of age, continued to grow, overwintered a second time, reproduced again, and died. The simulation model mimicked this pattern with considerable precision. Both the field data and the simulated output suggested that the population expanded during 1971, 1972, and 1973. No mechanisms for population limitation were found.

An experimental study of the surface elevation probability distribution and statistics of wind-generated waves

1980 ◽  
Vol 101 (1) ◽  
pp. 179-200 ◽  
Author(s):  
Norden E. Huang ◽  
Steven R. Long
Keyword(s):  
Experimental Study ◽  
Probability Density Function ◽  
Probability Distribution ◽  
Wave Field ◽  
Field Data ◽  
Laboratory Experiments ◽  
Laboratory Data ◽  
Surface Elevation ◽  
Strong Wind ◽  
Non Gaussian

Laboratory experiments were conducted to measure the surface elevation probability density function and associated statistical properties for a wind-generated wave field. The laboratory data together with some limited field data were compared. It is found that the skewness of the surface elevation distribution is proportional to the significant slope of the wave field, §, and all the laboratory and field data are best fitted by \[ K_3 = 8\pi\S, \] with § defined as ($(\overline{\zeta^2})^{\frac{1}{2}}/\lambda_0 $, where ζ is the surface elevation, and λ0 is the wavelength of the energy-containing waves. The value of K3 under strong wind could reach unity. Even under these highly non-Gaussian conditions, the distribution can be approximated by a four-term Gram-Charlier expansion. The approximation does not converge uniformly, however. More terms will make the approximation worse.

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