Ann: Settlement of Brazil Phosphate Project Acqui, page-4

re: Ann: Settlement of Brazil Phosphate Proje... NB.

"What is Auger drilling?

Auger drilling is done with a helical screw which is driven into the ground with rotation; the earth is lifted up the borehole by the blade of the screw. Hollow stem Auger drilling is used for environmental drilling,geotechnical drilling, soil engineering and geochemistry reconnaissance work in exploration for mineral deposits. Solid flight augers/bucket augers are used in construction drilling. In some cases, mine shafts are dug with auger drills. Small augers can be mounted on the back of a utility truck, with large augers used for sinking piles for bridge foundations.

Auger drilling is restricted to generally soft unconsolidated material or weak weathered rock. It is cheap and fast."

http://www.airdrill.com.au/index.php?view=article&catid=31%3Athe-drilling-industry&id=66%3Aauger-drilling&option=com_content&Itemid=41