Arbeitsbericht NAB 19-11

Lithology Manual Lithological description of drill cores and cuttings in Northern Switzerland

This document is a user manual for wellsite geologists and lithostratigraphy experts for describing and documenting the lithologies intersected in boreholes located in Northern Switzerland. The manual distinguishes between the description of drill cores and cuttings, and covers the entire lithological profile of Quaternary, Tertiary and Mesozoic sediments, as well as the uppermost interval of the crystalline basement, including Permian sediments.

Chapter 2 defines who is involved in the processes of drilling, drill core and cuttings description, interpretation and documentation of the described material.

Chapter 3 defines what needs to be done and is dedicated to the mandatory tasks to be performed by the various roles, with special focus on the tasks of the wellsite geologists (mudlogging service) and the lithostratigraphy experts. Step-by-step instructions are provided for different borehole types.

Chapters 4 and 5 provide a comprehensive catalogue of all abbreviations, graphical symbols and patterns to be used for the field manuscript and final presentation of lithostratigraphic sections. Drill core and cuttings samples are discussed in separate chapters.

The manual does not consider large-scale features that show in outcrop or tunnel profiles and thus may lack the associated symbols.