Instructional

Introduction

Drill cuttings are small rock or soil fragments produced when the drill bit breaks the subsurface material during drilling. They are carried to the surface by:

• Drilling fluid (mud)
• Air (air rotary / DTH)
• Water

Cuttings provide indirect information about subsurface geology. The main goals of drill cutting collection are to:

1. Identify lithology (rock/soil type)
2. Detect changes with depth
3. Identify aquifers
4. Support geological interpretation
5. Create a drill log

Drillers should collect representative sample sat measured depths and at intervals that will show the complete lithologic character of the borehole.