scholarly journals Fault growth and coalescence: insights from numerical modelling and sandbox experiments

GeoArabia ◽  
2007 ◽  
Vol 12 (1) ◽  
pp. 17-32 ◽  
Author(s):  
Jacek B. Filbrandt ◽  
Pascal D. Richard ◽  
Raymond Franssen
Keyword(s):  
Numerical Modelling ◽  
Growth Models ◽  
Sealing Capacity ◽  
Order Of Magnitude ◽  
Sandbox Experiments ◽  
State Growth ◽  
Fault Growth ◽  
Best Fit ◽  
Considerable Spread ◽  
Growth Evolution

ABSTRACT Displacement of strata varies along the strike of faults. This has important implications for the hydrocarbon industry, since for example this affects the occurrence and distribution of fractures along faults in a reservoir and can influence the sealing capacity of faults. As faults grow, neighbouring faults will interact with each other and eventually connect or coalesce. Geometrical fault growth models for coalescence are used to explain a large part of the observed spread of one order of magnitude in Length and Maximum Throw in natural examples of fault populations. Numerical modelling indicates that coalesced (merged) faults tend to return to their steady state growth evolution by accumulating displacement more rapidly than increasing in length, if no further coalescence occurs. Therefore, repetitive coalescence leaves faults “under-displaced” and results in a considerable spread in Length and Maximum Throw. To confirm and support these observations, a series of sandbox experiments was performed, which help improve our understanding of fault growth processes. The fault geometries observed in these models reflect geometries in natural examples, for example in the Natih Formation of Al Jabal al Akhdar in Oman. With increasing strain, repetitive coalescence takes place at all scales. After linkage, a new, coalesced fault behaves as a single, linked segment and accumulates more displacement than increasing length during an increment of strain. The slope of the best fit line of Length vs. Maximum Throw data for the fault population, in double logarithmic space, steepens with increasing strain and stabilises at about one.

Studies of calcium-45 desaturation from kidney slices in flow-through chambers

1978 ◽  
Vol 234 (1) ◽  
pp. R34-R38
Author(s):  
T. Uchikawa ◽  
A. B. Borle
Keyword(s):  
Kinetic Parameters ◽  
Rat Kidney ◽  
Kidney Cells ◽  
Tissue Slices ◽  
Kidney Slices ◽  
System A ◽  
Order Of Magnitude ◽  
Exponential Equations ◽  
Flow Through ◽  
Best Fit

This paper describes a method to measure calcium fluxes and calcium exchangeable pools in tissue slices by continuous perifusion in flow-through chambers. 45Ca desaturation from rat kidney slices can be analyzed as in an open three-compartment catenary system. A set of equations is given to calculate all the relevant kinetic parameters from the triple exponential equations which best fit the desaturation curves. The results show that the kinetic parameters obtained in kidney slices by this new method are in the same order of magnitude as those previously observed in cultured monkey kidney cells.

scholarly journals Fault Interpretation Uncertainties using Seismic Data, and the Effects on Fault Seal Analysis: A Case Study from the Horda Platform, with Implications for CO<sub>2</sub> storage

2021 ◽  
Author(s):  
Emma A. H. Michie ◽  
Mark J. Mulrooney ◽  
Alvar Braathen
Keyword(s):  
Fluid Flow ◽  
Seismic Data ◽  
Growth Models ◽  
Fault Analysis ◽  
Surface Generation ◽  
Co2 Injection ◽  
Line Spacing ◽  
Fault Growth ◽  
Fault Interpretation

Abstract. Significant uncertainties occur through varying methodologies when interpreting faults using seismic data. These uncertainties are carried through to the interpretation of how faults may act as baffles/barriers or increase fluid flow. How fault segments are picked when interpreting structures, i.e. what seismic line spacing is specified, as well as what surface generation algorithm is used, will dictate how detailed the surface is, and hence will impact any further interpretation such as fault seal or fault growth models. We can observe that an optimum spacing for fault interpretation for this case study is set at approximately 100 m. It appears that any additional detail through interpretation with a line spacing of ≤ 50 m adds complexity associated with sensitivities by the individual interpreter. Further, the location of all fault segmentation identified on Throw-Distance plots using the finest line spacing are also observed when 100 m line spacing is used. Hence, interpreting at a finer scale may not necessarily improve the subsurface model and any related analysis, but in fact lead to the production of very rough surfaces, which impacts any further fault analysis. Interpreting on spacing greater than 100 m often leads to overly smoothed fault surfaces that miss details that could be crucial, both for fault seal as well as for fault growth models. Uncertainty in seismic interpretation methodology will follow through to fault seal analysis, specifically for analysis of whether in situ stresses combined with increased pressure through CO2 injection will act to reactivate the faults, leading to up-fault fluid flow/seep. We have shown that changing picking strategies alter the interpreted stability of the fault, where picking with an increased line spacing has shown to increase the overall fault stability. Picking strategy has shown to have minor, although potentially crucial, impact on the predicted Shale Gouge Ratio.

scholarly journals Prediction of Mold Spoilage for Soy/Polyethylene Composite Fibers

2015 ◽  
Vol 2015 ◽  
pp. 1-11
Author(s):  
Chinmay Naphade ◽  
Inyee Han ◽  
Sam Lukubira ◽  
Amod Ogale ◽  
James Rieck ◽  
...  
Keyword(s):  
Growth Models ◽  
Storage Period ◽  
Weibull Model ◽  
Mold Growth ◽  
Growth Data ◽  
Final Model ◽  
Polyethylene Composite ◽  
Interaction Term ◽  
Environmental Temperatures ◽  
Best Fit

Mold spoilage was determined over 109 days on soy/PE fibers held under controlled temperatures (T) ranging from 10°C to 40°C and water activities(aw)from 0.11 to 0.98. Water activities were created in sealed containers using saturated salt solutions and placed in temperature-controlled incubators. Soy/PE fibers that were held at 0.823awor higher exhibited mold growth at all temperatures. As postulated, increased water activity (greater than 0.89) and temperature (higher than 25°C) accelerated mold growth on soy/PE fibers. A slower mold growth was observed on soy/PE fibers that were held at 0.87awand 10°C. A Weibull model was employed to fit the observed logarithmic values ofT, aw, and an interaction termlog⁡T×log⁡awand was chosen as the final model as it gave the best fit to the raw mold growth data. These growth models predict the expected mold-free storage period of soy/PE fibers when exposed to various environmental temperatures and humidities.

scholarly journals Derivation of Ice Sliding Properties from The Numerical Modelling of Surging Ice Masses

1979 ◽  
Vol 23 (89) ◽  
pp. 420-421 ◽  
Author(s):  
W. F. Budd ◽  
B. J. McInnes ◽  
I. Smith
Keyword(s):  
Shear Stress ◽  
Numerical Modelling ◽  
Sliding Friction ◽  
Two Dimensional ◽  
Dimensional Model ◽  
Flow Properties ◽  
Two Dimensional Model ◽  
Two Parameters ◽  
Basal Shear ◽  
Best Fit

Abstract It is difficult to deduce sliding properties from the numerical modelling of ordinary glaciers because the flow law of ice is still not known well enough to clearly differentiate sliding from internal deformation of the ice. For glaciers undergoing high-speed surges it appears that the majority of the total speed is due to sliding. Furthermore the average basal shear stress of the ice mass is lowered during the surge. This suggests that surging glaciers can be modelled by incorporating a sliding friction law which has the effective friction coefficient decreasing for high velocities. A relation of this type has been found for ice sliding on granite at −0.5°C by Barnes and others (1971) and has also been obtained for rough slabs with ice at the pressure-melting point by Budd and others (1979). A simple two-dimensional model was developed by Budd and McInnes (1974) and Budd (1975), which was found to exhibit the typical periodic surge-like characteristics of real ice masses. Since the sliding-stress relation for the low velocities and stresses was not known, and was not so important for the surges, it was decided to use the condition of gross equilibrium (i.e. that the ice mass as a whole does not accelerate) together with a single-parameter relation for the way in which the friction decreases with stress and velocity to prescribe the basal shear-stress distribution. The low-stress-velocity relation can thus be obtained as a result. This two-dimensional model has now been parameterized to take account of the three-dimensional aspects of real ice masses. A number of ice masses have since been closely matched by the model including three well-known surging ice masses: Lednik Medvezhiy, Variegated Glacier, and Bruarjökull. Since the flow properties of ice are so poorly known—especially for longitudinal stress and strain-rates—the model has been run with two unknown parameters: one a flow-law parameter (η) and the other a sliding parameter (ø). The model is run over a wide range of these two parameters to see if a good match can be made to the real ice masses and if so what the values of the parameters η and ø are for best fit. The matching of the three above ice masses gave very similar values for each of the two parameters η and ø, the value of η being within the range of values expected for the flow properties of temperate ice as determined by laboratory experiments. Using the same values of η and ø it is found that the ordinary glaciers modelled so far do not develop surging but that they could do if the value of ø were increased or if the mass-balance input were sufficiently increased. For Lednik Medvezhiy a detailed analysis of the friction coefficient with velocity was carried out and it was found that the values required for best fit showed a very close agreement to the sliding friction curve of Barnes and others (1971) at −0.5°C. It is concluded that this type of sliding relation can account for the major features of glacier surge phenomena. Finally it is apparent that the numerical modelling technique can be used very effectively to test any large-scale bulk sliding relation by the analysis of real surges of ice masses and in addition can provide further insight into the sliding relation in association with other stresses in the ice mass.

Prediction of dry matter accumulation in bitter vetch

2017 ◽  
Author(s):  
Ufuk Karadavut ◽  
Adil Bakoglu ◽  
Halit Tutar ◽  
Kagan Kokten ◽  
Hava Seyma Yilmaz
Keyword(s):  
Growth Models ◽  
Block Design ◽  
Coefficient Of Determination ◽  
Dry Matter Accumulation ◽  
Randomized Block Design ◽  
Bitter Vetch ◽  
Best Fitting ◽  
Local Genotypes ◽  
Best Fit ◽  
Different Sources

This study was carried out in Bingol province on eastern Anatolian Region between 2013 and 2015. In this study, we obtained 14 bitter vetch genotypes from different sources. The experiment was carried our in three replications in randomized block design. Each plant was weekly measured for 6 weeks starting from germination. For each plant, plant height, fresh and dry stem weight, fresh and dry leaf weights were determined. Logistic, Richards and Weibull growth models were fitted to describe the growth pattern of the genotypes. The best fitting model criteria used were coefficient of determination and mean squared. Richards’s growth model was found to best fit the data for most of the genotypes. Logistic model was the worst fit. In Turkey, climate and soil properties have very large variations. For this, local genotypes showed large variation according to plating areas. YEREL LICE genotype showed more stable and it is the height identified all growth models than other local genotypes. However, IFVE 2923 SEL and IFVE 2977 SEL 2802 these genotypes gave positive results in different environmental conditions.

scholarly journals Age, growth, and maturity of the whitebrow skate, Bathyraja minispinosa, from the eastern Bering Sea

2011 ◽  
Vol 68 (7) ◽  
pp. 1426-1434 ◽  
Author(s):  
Shaara M. Ainsley ◽  
David A. Ebert ◽  
Gregor M. Cailliet
Keyword(s):  
Bering Sea ◽  
Growth Models ◽  
Gompertz Model ◽  
Parameter Estimates ◽  
Population Declines ◽  
Age At Maturity ◽  
Von Bertalanffy Model ◽  
Eastern Bering Sea ◽  
Best Fit ◽  
The Bering Sea

Abstract Ainsley, S. M., Ebert, D. A., and Cailliet, G. M. 2011. Age, growth, and maturity of the whitebrow skate, Bathyraja minispinosa, from the eastern Bering Sea. – ICES Journal of Marine Science, 68: 1426–1434. Skates are a common bycatch in groundfish fisheries in the Bering Sea; however, their life-history characteristics are not well known. The study is the first to investigate the age, growth, and age at maturity of Bathyraja minispinosa. Ages were estimated using sectioned vertebrae and several growth models were compared. The Gompertz model was the best fit and no significant differences were detected between sexes for any model. The maximum age estimated was 37 years, and parameter estimates generated from the three-parameter von Bertalanffy model were k = 0.02 year−1 and L∞ = 146.9 cm total length (TL). Males reached their size at 50% maturity larger than females (70.1 and 67.4 cm, respectively), but no significant differences in the estimated size or age at maturity were found. Whereas B. minispinosa is smaller than many skate species in the eastern Bering Sea, it has a considerably longer estimated lifespan, indicating that size may not be a reliable method of estimating the vulnerability of a rajid species to population declines in the eastern North Pacific.

scholarly journals Selecting the best growth model for elasmobranches

2015 ◽  
Author(s):  
Kwang-Ming Liu ◽  
Chiao-Bin Wu ◽  
Shoou-Jeng Joung ◽  
Wen-Pei Tsai
Keyword(s):  
Growth Model ◽  
Growth Models ◽  
Stock Assessment ◽  
Gompertz Model ◽  
Information Criterion ◽  
Age And Growth ◽  
Deep Waters ◽  
Extended Longevity ◽  
Best Fit ◽  
Two Parameter

Age and growth information is essential for accurate stock assessment of fish, and growth model selection may influence the result of stock assessment. Previous descriptions of the age and growth of elasmobranches relied mainly on the von Bertalanffy growth model (VBGM). However, it has been noted that sharks, skates and rays exhibit significant variety in size, shape, and life-history traits. Given this variation, the VBGM may not necessarily provide the best fit for all elasmobranches. This study attempts to improve the accuracy of age estimates by testing four growth models—the VBGM, two-parameter VBGM, Robertson (Logistic) and Gompertz models—to fit observed and simulated length-at-age data for 37 species of elasmobranches. The best growth model was selected based on corrected Akaike’s Information Criterion (AICc), the AICc difference, and the AICc weight. The VBGM and two-parameter VBGM provide the best fit for species with slow growth and extended longevity (L∞ > 100 cm TL, 0.05 < k < 0.15 yr-1), such as pelagic sharks. For fast-growing small sharks (L∞ < 100 cm TL, kr or kg > 0.2 yr-1) in deep waters and for small-sized demersal skates/rays, the Robertson and the Gompertz models provide the best fit. The best growth models for small sharks in shallow waters are the two-parameter VBGM and the Robertson model, while all the species best fit by the Gompertz model are skates and rays.

scholarly journals On the theoretical prediction of microalgae growth for parallel flow

2020 ◽  
Author(s):  
Chunyang Ma
Keyword(s):  
Growth Rate ◽  
Growth Models ◽  
Concentration Field ◽  
Parallel Flow ◽  
Biofuel Production ◽  
Order Of Magnitude ◽  
Growth Problem ◽  
Semi Empirical ◽  
First Time ◽  
Microalgae Growth

Abstract Background: The established microalgae growth models are semi-empirical or considerable fitting coefficients exist. Therefore, the ability of the model prediction is reduced by the numerous fitting coefficients. Furthermore, the predicted results of the established models are dependent on the size of the photobioreactor (PBR), light intensity, flow and concentration field. The growth mechanism of microalgae has not clearly understood in PBR cultivation. It is difficult to predict the microalgae growth by theoretical methods, owing to the aforementioned factors. We developed an exploratory bridging microalgae growth model to predict the microalgae growth rate in PBRs by using the nondimensional method which is effectively in fluid dynamics and heat transfer. Results: The analytical solution of the growth rate was obtained for the parallel flow. The nondimensional growth rate expressed as function of Reynolds number and Schmidt number, which can be used for arbitrary parallel flow due to the solution was expressed as nondimensional quantities. The theoretically predicted growth rate is compared with the experimentally measured microalgae growth rate on the order of magnitude. Conclusions: The nondimensional method successfully applied to the microalgae growth problem for the first time. The general nondimensional solution can unify the numerous experimental data for different laboratory conditions, and give a direction for the disorder of the microalgae growth problem. The nondimensional solution will be useful in the design and operation of PBRs for biofuel production.

scholarly journals Mathematical model of growth of two purelines of Padjadjaran female quail aged 0 to 6 weeks

2017 ◽  
Vol 42 (2) ◽  
pp. 66
Author(s):  
A. Anang ◽  
H. Indrijani ◽  
E. Sujana
Keyword(s):  
Growth Models ◽  
Gompertz Model ◽  
High Accuracy ◽  
Coefficient Of Determination ◽  
Standard Errors ◽  
Black Line ◽  
Female Quail ◽  
Best Fit ◽  
Black Color ◽  
Brown Color

A research was conducted at Quail Breeding Centre of Padjadjaran University.  A hundred quails of female black and brown color of each line was observed from hatch to age of six weeks. Four growth models were compared: Gompertz, Logistic, Richards, and MMF. The best fit was measured with Coefficient of determination (R2) and standard error of prediction (se). The results showed that all observed models have high accuracy with R2 ranging from 0.9950 to 0.9988 for black color, and 0.9984 to 0.9992 for brown color respectively. Standard errors of prediction (SE) ranged from 1.99 g to 4.01 g for black, and from 1.92 g to 2.52 g for brown, respectively. Gompertz model was more favorable with R2 and SE of 0.9988 and 1.99 g for black, and 0.9991 and 1.92 g for brown, respectively. Age at inflection, maximum average daily gains and weights at inflection were 4.18 week, 27.87 g and 100.23 g for black line and 3.38 week, 25.05 g and 75.34 g for brown line, respectively.

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