Well correlation

Usually well logs are only one type of data used to establish a correlation. Any meaningful interpretation will need to be supported by palaeontological data (micro fossils) and 

Relative sea level changes affect many shallow marine and coastal depositional environments. 

we align all logs at the datum plane which now becomes a straight horizontal line. Note that by doing so we ignore all structural movements to which the sequence has been exposed. 

We can now correlate all events below or above the datum plane by comparing the log response. In many instances correlations are ambiguous. Where two or more correlation 

If correlation is lost , that is if no similarity exists any more between the log shapes of two wells (such as in well 2 in our example) this could be for a number of reasons  

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Semiempirical, DFT, and ah initio methods also work well. Correlation effects are sometimes included for the sake of increased accuracy, but are not always necessary. One particular case for which correlation is often necessary is fluorine compounds. 

Acid amide herbicides are nonionic and moderately retained by soils. The sorption of several acid amide herbicides has been investigated (369). Acetochlor [34256-82-1] is sorbed more than either alachlor or metolachlor, which are similarly sorbed by a variety of soils. Sorption of all the herbicides is well correlated to soil organic matter content. In a field lysimeter study, metolachlor has been found to be more mobile and persistent than alachlor (370) diphenamid [957-51-7] and napropamide [15299-99-2] have been found to be more readily leached (356). 

Fig. 5.20. The shock-induced polarization of a range of ionic crystals is shown at a compression of about 30%. This maximum value is well correlated with cation radius, dielectric constant, and a factor thought to represent dielectric strength. A mechanically induced point defect generation and migration model is preferred for the effect (after Davison and Graham [79D01]).

Because 5 is not well correlated with Ei, these two steric constants contain different information. Berg et al. conclude that S is a measure of the pure steric effect. 

It is interesting to speculate why the basicities of the substituted pyridines are well correlated by normal a-values, rather than by a+-values. Writing the resonance structures for the conjugate acid (5<->6)... 

Closely related to the basicity of pyridine is its hydrogen-bonding ability two indices of this property have been measured for a very short series of substituted pyridines and are very well correlated by CT-values. ... 

Another rather extensive series of similar data, obtained using CS2 solutions and nujol mulls, has been published by Shindo (Fig. 4). His series include considerable data for jS-substituted compounds, for which the question of a choice of substituent constants does not arise. His data also show considerable scatter but seem to suggest strongly that <7+-values are indicated for + M substituents and normal <7-values for —M substituents. The conclusion is confirmed by the short series of similar data reported by Costa and Blasina and by Shupack and Orchin. The data of the latter authors for the NO frequencies in mws-ethylene pyridine N-oxide dichloroplatinum(II) complexes are also moderately well correlated with <7+-values. 

Shindo studied the hydrogen-bonding ability of a fairly long series of substituted pyridine 1-oxides with methanol in chloroform solution and found that the OH frequency of the hydrogen-bonded OH group in methanol is well correlated with the <7-values. For four compounds, the intensity of the same band is also well correlated. In a similar study the OH frequencies of phenol vary monotonically with the CT-values, but not in a linear fashion. 

Illuminati et al. have also investigated the methoxydechlorination of 4-substituted-2- and 2-substituted-4-chloroquinolines. The relation between the reaction site, the 2- or 4-position, and the substituent in the 4- or 2-position, respectively, is always meta. The authors found the two reaction series well correlated with one another, but diverging quite seriously from the Hammett correlation. They concluded that mesomerically electron-donating substituents, because of the importance of resonance structures like 12 and 13, are more deactivating than expected, while electron-withdrawing substituents, and even the methyl group, seem to follow normal a correlation. 

Below the loading region, the pressure drop can be read from appropriate system curves if they are a ailable, as Figure 9-20. However, for general use the data have been well correlated. Figures 9-21B-9-21F. The slope of most of the curves for pressure drop indicate a proportionality of 1,8 to 2.8 power of the superficial gas mass... 

The tenderometer is not readily adaptable for measurement of maturity in the finished product, and any method used for estimating maturity at this point should yield results well correlated with those obtained by the tenderometer. Estimation of total solids or starch content appears to fulfill this requirement very well. 

Recent studies have found enhanced substituent solvation assisted resonance effects in dipolar non-hydrogen bonding solvents131. For several +R substituents acidities of phenols in DMSO are well correlated with their gas-phase acidities. The substituents include m- and p-SOMe, m- and p-S02Me, m-S02CF3 and m-N02. But there is very considerable enhancement of the effect of p-S02CF3, p-N02 and various other para-substituents in DMSO solution. 

McDowell and Stirling194 studied electronic effects upon the reactivity of aryl vinyl sulfones towards amines. Rate constants for t-butylamine addition in ethanol at 25 °C were well correlated by the Hammett equation, with p = 1.59. Comparison of this with p values for H-D exchange mentioned above191 suggested considerable carbanionic character in the transition state, perhaps in a concerted mechanism. Rates of addition of amines to alkenyl, allenyl and alkynyl p-tolyl sulfones have also been measured195. 

The data for heating and cooling water in turbulent flow in rectangular ducts are reasonably well correlated by the use of equation 9.59 in the form ... 

Experimental work has been carried out with exchangers in which the inside tube was 48 mm outside diameter and was fitted with 24, 28, or 36 fins (12.5 mm by 0.9 mm) in a 6.1 m length the finned tubes were inserted inside tubes 90 mm inside diameter. With steam on the tube side, and tube oils and kerosene on the fin side, the experimental data were well correlated by plotting ... 

SHERWOOD and Pigford(7) found that the effect of the Schmidt group was also influenced by the Reynolds group and that the available data were, fairly well correlated as shown in Figure 10.16, in which (hod )/D is plotted against Re Sc0-67. 

Fe(CN)g was noted and the kinetics were further complicated by specific ionpairing effects. However, an electron transfer mechanism is plausible and the rate coefficients with different oxidants agreed reasonably well (correlation coefficient 0.966) with those calculated from... 

Marriott and Topsom have recently developed theoretical scales of substituent field and resonance parameters. The former correspond to the traditional inductive parameters but these authors are firm believers in the field model of the so-called inductive effect and use the symbol The theoretical substituent field effect scale is based on ab initio molecular orbital calculations of energies or electron populations of simple molecular systems. The results of the calculations are well correlated with Op values for a small number of substituents whose Op values on the various experimental scales (gas-phase, non-polar solvents, polar solvents) are concordant, and the regression equations are the basis for theoretical Op values of about 50 substituents. These include SOMe and S02Me at 0.37 and 0.60 respectively, which agree well with inherent best values in the literature of 0.36 and 0.58. However, it should be noted that a, for SOMe is given as 0.50 by Ehrenson and coworkers . 

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