Sampling Unconsolidated Materials

The method of collecting cable-tool cutting samples from holes drilled in unconsolidated materials is no different than collecting samples from hard-rock holes. However, if the driller is competent, his log interpretation of the drilled material must be heavily relied upon. R>r instance, examining the cuttings from a bailed-out section may indicate they came from a formation of dirty sand; however, the competent driller knows by feel and reaction of the drill bit that he actually drilled a gravel layer and a clay or silt-clay layer. The sample is a ground-up mixture of these layers; without the driller's-log input, an inaccurate lithologic tog will be constructed.

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