Petrographic image

This paper reports an investigation of the effects of porous solid structures on their electrical behaviour at different frequencies (from 100 Hz to 100 kHz). For that, we study different parameters such as formation resistivity factor, cementation factor, chargeability, resistivity index and saturation exponent. Different porous solid structures are quantified from the petrographic image analysis and Hg-injection technique. Then, by using different models we obtain the permeability prediction from the electrical behaviour and structure parameters. 

England, B.M. Mikka, R.A. Bagnall, B.J. Petrographic Characterization of Coal Using Automatic Image Analysis, J. Microscopy. 1979, 116, 329-336. 

Image analysis of stained slabs (Duncan 1999) indicates these rocks should probably be referred to as ( ) augite syenite, ( ) hornblende quartz syenite, and ( V) biotite syenogranite (from mean petrographic classification Fig. 2). 

Because SEM-AIA is often used to explain behavior under specific processing conditions, samples are prepared in the same size in which they are received. Coal samples with their included mineral matter are prepared for image analysis by mixing samples. of the dry coal with polyethylene powder (as a diluent) and molten carnauba wax in a volume ratio of 1 2 2. Pellets are then cut along the cylindrical axis to expose a vertical cross section of coal and mineral matter and polished using standard petrographic procedures. The surfaces are coated with 150 A of carbon to provide a conductive surface for SEM examination. 

Figure 20 (A) SEM images of Celtis Occidentalis (Hackberry) endocarp. Aragonite deposited in a (a) honeycomb pattern, (b) the inner silica scaffolding, and (c) organic matter occluded within the silica (scale bar = 10 p,m) (source A. H. Jahren, unpublished collection). (B) Petrographic thin section of Celtis Occidentalis (Hackberry) endocarp, note honeycomb pattern (scale bar = 100 p,m). Photograph taken with crossed polars and quartz plate inserted...

Fig. 4.38 A petrographic microscope with component parts labeled. Image courtesy of the University of Cambridge DoITPoMS Micrograph Library...

Fig. 4. Petrographic, BSE and colour image characteristics of Tirrawarra Sandstone siderites. (A) Plane-polarized view of the main siderite cement generations that can be distinguished under the optical microscope in this case, which is the exception rather than the rule. SI has a brownish colour, whereas S2 and S3 are clear and colourless. SI is typically engulfed by S2. Note the concentration of fluid inclusions in S2, and the irregular serrated boundary between S2 and S3 (arrow), implying some dissolution of S2 prior to precipitation of S3. Sample Ml-9598, Moorari 1, 2925.5 m.

---