2006-07 End of Season Field Reports

Ice Drilling Design and Operations (IDDO) group Activities at WAIS Divide 2006-2007 (T-350)
NSF-OPP supported
PI: Charles Bentley (University of Wisconsin-Madison)

Field Team:

Beth Bergeron Brent Folmer    
Michael Jayred Jay Johnson    

Season Objectives:
ICDS had four major objectives at WAIS Divide during the 2006-2007 field season:
1. Core a 130-meter hole outside the drill arch
2. Drill and case a 100-meter pilot hole inside the drill arch for the deep core project
3. Install the 9-ton DISC Drill gantry crane inside the drill arch
4. Test the effect on core quality using a small amount of drilling fluid in a 300-meter hole

Core 130-Meter Hole:
Beth Bergeron and Michael Jayred arrived at WAIS Divide on November 29 and began coring the hole outside the drill arch using a 4-Inch drill. A depth of 133 meters was reached on December 7 and the crew moved the drill into the arch to drill the pilot hole on December 8. Joe Souney of the University of New Hampshire and the WAIS Divide Science Coordinating Office processed the core.

Drill and Case Pilot Hole:
Bergeron and Jayred began drilling the pilot hole on December 9 after RPSC cut a slot in the floor of the drill arch for the drill pit. Coring of the hole with the 4-Inch drill was completed on December 13 at a depth of 114 meters. The core from the hole was collected and processed by Joe Souney.

Reaming of the hole began on December 13. Jay Johnson and Brent Folmer arrived at site on December 13. Reaming of the hole was completed on December 27 with the top 88.5 meters of the hole reamed to 12 inches in diameter, the hole from 88.5 meters to a depth of 91.5 meters reamed to 7 inches in diameter, and the hole between 91.5 meters and approximately 111 meters deep reamed to 7 inches in diameter. The top 88.5 meters of the hole was cased using a 9 1/2-inch inside diameter, 10 3/4-inch outside diameter HDPE pipe. Casing of the hole was completed December 26.

Johnson, Jayred, and Folmer left WAIS Divide on December 27.

Install Gantry Crane:
ICDS shipped both of its gantry cranes to WAIS Divide with the goal of getting at least the 9-ton crane installed during the 2006-2007 season to facilitate the assembly of the drill system during the 2007-2008 field season. Both the 9-ton crane and the 2-ton crane used for handling the drill sonde were assembled and tested using a temporary generator.

Test Effect of Using Small Amount of Drilling Fluid:
ICDS used the opportunity afforded by having the 4-Inch drill at WAIS Divide to test the effect on core quality of using a small amount of drilling fluid as a cutting "lubricant". After the completion of the drilling and casing of the pilot hole, ICDS Engineer Jay Kyne and Beth Bergeron used the 300-meter hole drilled during the 2005-2006 field season for the test. The hole had closed enough during the year that it had to be reamed from approximately 250 meters to the bottom. Several cores were collected drilling without the fluid, but core quality did not equal that achieved during the 2005-2006 season. Unfortunately, the use of the drilling fluid did not seem to improve the quality either. Results will be evaluated.