Measurement Depth

In preparation for a field wide quick look correlation, all well logs need to be corrected for borehole inclination. This is done routinely with software which uses the measured depth below the derrick floor ( alonghole depth below derrick floor AHBDFor measured depth , MD) and the acquired directional surveys to calculate the true vertical depth subsea (TVSS). This is the vertical distance of a point below a common reference level, for instance chart datum (CD) or mean sea level (MSL). Figure 5.41 shows the relationship between the different depth measurements. 

In order to provide measuring of cracks depth on complicated profile areas there is a special function in the device. The function makes it possible to perform measurements by studying on a samples with defects of the measured depth. 

NRA is an effective technique for measuring depth profiles of light elements in solids. Its sensitivity and isotope-selective character make it ideal for isotopic tracer experiments. NRA is also capable of profiling hydrogen, which can be characterized by only a few other analytical techniques. Future prospects include further application of the technique in a wider range of fields, three-dimensional mapping with microbeams, and development of an easily accessible and comprehensive compilation of reaction cross sections. 

Today dynamic SIMS is a standard technique for measurement of trace elements in semiconductors, high performance materials, coatings, and minerals. The main advantages of the method are excellent sensitivity (detection limit below 1 pmol mol ) for all elements, the isotopic sensitivity, the inherent possibility of measuring depth profiles, and the capability of fast direct imaging and 3D species distribution. 

Approaching formation bed boundaries are detected by concurrent separation and displacement of the high and low gamma counts. These are shown in Figure 4-271 at measured depth intervals (7970-7980 ft) and (8010-8020 ft). 

Radioactive events occur in the measured depth interval (8,100-8,200 ft) with no displacement of the low/high side gamma ray logs. The radioactive events must be perpendicular to the gamma detector and could be indications of vertical natural fractures in the formation. 

Measured depth Actual length of the wellbore from its surface location to any specified station. 

Figure 4-367 shows a pipe stuck at some depth (ft) less than the total measure depth D (ft). The length is the distance to the free point, or the length from the surface to where the pipe stuck. To obtain the following procedure is carried out ... 

Flerman, R. S., Radiographic-Photographic Method for Measuring Depth and Distribution of Pitting , Corrosion, 20, 361 (1964)... 

Implantable microelectronic devices for neural prosthesis require stimulation electrodes to have minimal electrochemical damage to tissue or nerve from chronic stimulation. Since most electrochemical reactions at the stimulation electrode surface alter the hydrogen ion concentration, one can expect a stimulus-induced pH shift [17]. When translated into a biological environment, these pH shifts could potentially have detrimental effects on the surrounding neural tissue and implant function. Measuring depth and spatial profiles of pH changes is important for the development of neural prostheses and safe stimulation protocols. 

A quantitative and fairly easy method to obtain particle reworking rates in deep sea sediments became possible after the elegant work of Nozaki et al., [68] based on 210Pb distribution in them. The radioactive half-life of 210Pb is too short (22.6 yrs) to produce measurable depth profiles in deep sea sediments based on sedimentation alone since its activity would be limited to the top 1 mm layer. In such a case its depth profile predominantly records the effects of particle reworking and its distribution can be approximated as ... 

Variation of Cs adsorption with depth, as a function of changes in clay content, is reported by Melkior et al. (2005) the study aimed to test the efficiency of a host rock for radionuclide confmement. Mudrock samples were collected from Callovo-Oxfordian layers in Bure (France), at depths between 22m and 78m. The total clay content increases with depth by a factor of two to three between the measured depths. Figure 8.37 depicts the of Cs as a function of its concentration in solution at equilibrium. 

Method Process Particles/ ray measured Depth resolution Lateral resolution Imaging possibility Detection limits Strengths of technique Limitations of technique... 

Jester, J.V, Ling, J., HarbeU, J. Measuring depth of injury (DOI) in an isolated rabbit eye irritation test (IRE) using biomarkers of cell death and viability. Toxicol In Vitro 24(2), 597-604 (2010). Epub 2009 Oct 24... 

According to the purpose of the measurement, we may take results expressed in measuring depth, reflecting the wearability of a material, or expressed in Mohs hardness units. The possibility of converting from depth measurement to H0 hardness classes conforming to the Mohs scale, consistent with Vickers hardness (Fig. 4.4.11), may provoke some reservations. For this reason, therefore, A. Szymanski and J. M. Szymanski (1976) tried... 

Ruler for measuring depth to which prod is buried. Optional large (e.g., 10 cm) object associated with shock. 

Megaelectron volt (MeV) ion beam techniques offer a number of non-destructive analysis methods that allow to measure depth profiles of elemental concentrations in material surfaces. Elements are identified by elastic scattering, by specific nuclear reaction products or by emission of characteristic X-rays. With nuclear microprobes raster images of the material composition at the surface can be obtained. Particle-induced gamma-ray emission (PIGE) is especially suited for fluorine detection down to the ppm concentration level. 

Fig. 4.3 Expressing water table in altitude units (relative to sea level). The measured depth AB is subtracted from the altitude of point A, determined by direct measurement or read from topographic map. In the example, the reference point A has been determined to be 622 masi and the depth of the water table is 22 m. Hence, the water table in this well is 622 — 22 = 600 masi.

Figure 4.21 depicts temperature profiles in a well close to the Mohawk River, New York. In May a temperature of 43° F is observed at the measured depth interval of 205-165 ft above sea level. The July profile looked totally different it showed 57° F at the top, 64° F at the center, and 52° F at the bottom. The January profile looks different again 56° F at the top, 68° F at the center, and 52° F at the bottom. The interpretation of these temperature profiles is discussed in section 4.8. For our present topic, the planning of hydrochemical studies, it is important to keep in mind that water strata are not necessarily uniform—if they vary in their temperature profiles, they may vary in other parameters as well. 

Planning of a hydrochemical study has to take into account the need to measure depth profiles and to select the proper time to do them. 

Potential uses of temperature data have been discussed in sections 4.7-4.9. The ease with which temperature is measured and the benefits to the understanding of groundwater systems make the measurement of this parameter a must in every study. This is also true for repeated measurements, depth profiles, and pumping tests. 

Measuring depth profiles in nonpumped wells to search for different water strata (section 7.3). 

Ion irradiation of PTFE and plasma-fluorinated PMDA-ODA has been performed under typical conditions of RBS analysis. Loss of fluorine is observed on all films, especially at the start of irradiation. Decomposition is introduced by the beam interaction with the polymer defluorination and formation of carbon-carbon double bonds are detected by XPS and FTIR. For PTFE, irradiation produced films which were brittle and blistered. The calculated stopping power for He2+ ions and the experimentally measured depth of damage are approximately the same. 

Fig. 9 Changes in the crack initiation times and crack depths in an epoxy resin as a function of the amplitude of the imposed cyclic displacement, a Number of cycles to the initiation of the primary cracks at the edge of the contact zone, b Measured depths of the primary cracks at various number of cycles and displacement amplitudes. Circles 103 cycles, solid diamonds 5 x 103 cycles, squares 5 x 104 cycles, c Calculated values of the maximum tensile stress at the edge of the contact using Hamilton (gross slip condition) or Mindlin—Cattaneo (partial slip condition) theories. The two curves correspond to calculations using the initial (/x = 1.0) and the steady-state (/x = 1.5) values of the coefficient of friction. PSR Partial slip regime, MR mixed regime, GSR gross slip regime...

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