ABSTRACT
Features of the borehole wall can be observed from digital camera images, e.g. water erosion, biological invasion and erosion, rock fissures, etc.
The image can also be used to discover regions with significant variations in cementation conditions, e.g. variations of compactness, granularity,
colors, For segments of low or zero coring rates, the images can be used to determine the characteristics of the strata and causes of the low coring rate, e.g. cavities, low cementation, problems with the drilling process, etc. Table 1 displays some examples of special regions in coral reefs.
