A boring log is a description of exploration procedures and subsurface conditions encountered during drilling, sampling, and coring. Following is a brief list of items included in a boring log:

Topics:

• Topographic survey data including boring location and surface elevation, and benchmark location, and datum, if available.
• An accurate record of any deviation in the planned boring locations.
• Identification of the subsoils and bedrock including density, consistency, color, moisture, structure, geologic origin.
• The depths of the various generalized soil and rock strata encountered.
• Sampler type, depth, penetration, and recovery.
• Sampling resistance in terms of hydraulic pressure or blows per depth of sampler penetration.
• Size and type of hammer; Height of drop.
• Soil sampling interval and recovery.
• Rock core run numbers, depths & lengths, core recovery, and Rock Quality Designation (RQD).
• Type of drilling operation used to advance and stabilize the hole.
• Comparative resistance to drilling.
• Loss of drilling fluid.
• Water level observations with remarks on possible variations due to tides and river levels.

Intended Audience:This course is intended for Geotechnical, Civil, Construction, Hydraulic Structural, Foundations, and other engineers whose job description may require an intermediate knowledge of soil testing methods, procedures, and boring log interpretation.

Publication Source:USDOT (Federal Highway Administration)

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