Sidewall coring

In a more recent development a new wireline tool has been developed that actually drills a plug out of the borehole wall. With sidewall coring (Fig. 5.36) some the main disadvantages of the SWS tool are mitigated, in particular the crushing of the sample. Up to 20 samples can be individually cut and are stored in a container inside the tool. 

With time, however, the company encountered problems, including caving of the formation into the wellbore and the loss of permeability in zones that had accepted fluid. In June 1987, a number of sidewall cores were taken from the formation (Mehnert et al., 1990). Mineralogic analysis by x-ray diffraction showed that significant amounts of calcite (CaCCb) and brucite [Mg(OH)2], as well as some amorphous matter, had formed from the original dolomite. In some samples, the dolomite was completely consumed and the rock was found to be composed entirely of a mixture of brucite and calcite. 

Analysed gases and oils are bottom-hole samples unless otherwise indicated in the text or figures. Bottom-hole samples (BHS) and cores generally predate enhanced oil recovery activity (1979-1984), thus represent original field conditions. Exceptions include multiple dynamic formation test (MDT) oils, repeat formation tester (RFT) oils, sidewall cores (SWC), or separator oil samples from recent wells usually at the periphery of the field. 

Long chain alkyl aromatic (LCAA) hydrocarbons have been selectively depleted. Core and sidewall core samples from the most severely tar plugged sands (2E-17 and lJ-14) had the most extensive removal of LCAAs. All analysed incidences of tar or viscous oil corresponded to depleted LCAA. 

Model predictions, followed by analyses of in-situ sidewall core samples, showed that amorphous silica, calcite and lesser amounts of gypsum are the dominant phases expected to precipitate in the... 

Figure 5. Volume percent change in amorphous silica abundance in fractures. Filled circle indicates sidewall core sample locations where it was observed.

Keywords d rec methods, indirect methods, rock properties, coring, core barrel, standard core analysis, special core analysis, slabbed core, sidewall samples, direct indications, microfossils, sonde, logging unit, invasion, mudcake, formation pressure measurement, fluid sampling, measurement while drilling, formation evaluation while drilling. 

The most widely used approach to channel flow calculations assumes a steady qua si-one-dimensional flow in the channel core, modified to account for boundary layers on the channel walls. Electrode wall and sidewall boundary layers may be treated differently, and the core flow may contain nonuniformities. 

To sample with airtight coring devices, we must have access to exposed soil, which may be the ground surface, the bottom and sidewalls of an excavation, the stockpile face or side, or soil in the excavator bucket. We may also apply this technique for sampling of subsurface soil brought to the ground level in a split spoon sampler. 

Porosity data can be obtained from laboratory measurements on sidewall samples and core samples from boreholes (e.g. Monicard, 1981), from geophysical well logs (sonic, density and neutron logs Serra, 1987) or from seismic data. 

Polysar H DM. iiles/Pdysar Rubber] EPDM polymers for iig. mdding, hose and ptc e extrusion, sponge and cast coring, roofing membranes, black sidewalls. 

The chassis structure of the hybrid low-floor COBRA tram consists of a frame and a floor module, made of welded aluminum (hollow extrusions [3]) (Fig. 32.9). The composite sandwich roof panel is glued with elastic adhesives to the aluminum roof cant rail. All heavy aggregates are positioned on top of the composite roof panel. Due to the foam core, the loads had to be introduced by additional profiles (connected to the roof cant rail) to smoothen any local peaks. The GRP sidewall panels are joined to the aluminum pillars and the major longitudinal extrusions by long running layers of the elastic adhesive Sikaflex -254 Booster. The structural analysis of this tram vehicle proved the structural integrity of the new design for the load history specified. The stiffness of the structure has been sufficient to fulfill all the deformation criteria (Fig. 32.10). Based on these results, the preproduction series of the first six COBRA trams was produced and is in normal service operation an additional 68 trams will have followed by 2010. 

The inversion of this principle is also possible, with the shape of the outside of the sidewall cut into the cavity, and the cores which create the opening left standing so that they will shut off on the side of the (main) core. The advantage of this arrangement is that the radii can be on the outside of the product, but the inside would then have sharp comers. This method is generally not desired, for two reasons ... 

Song et al. [67] prepared PLA/CNT nanocomposites by one step based on in situ polycondensation of the commercially available lactic acid monomer in the presence of purified CNTs. The TEM image (Fig. 11.5) of core/shell nanostructures clearly indicates that the coating of grafted polymer was uniform both on the CNT s sidewall and tip. It was suggested that the incorporation of CNT into PL A will improvement its solubility and biocompatibility as it may promise a good future in biomedical systems and the development of bio-nanomaterials. The researchers also suggested that the current method of PLA/CNT nanocomposites preparation should be favored in industrialization as it takes less steps and cheaper. 

Tire treads/ sidewalls, golf ball n cores... 

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