Clean subglacial access: prospects for future deep hot-water drilling

Area of Science:

• * Polar Science
• * Earth Science
• * Drilling Technology

Background:

• * Accessing deep Antarctic subglacial environments requires specialized drilling techniques adhering to environmental protection agreements.
• * Clean hot-water drilling is the preferred method for reaching subglacial lakes, necessitating advanced systems for greater depths and operational integrity.
• * The Subglacial Lake Ellsworth (SLE) project aimed for deep (3000m+) research using a clean deep-ice hot-water drill.

Purpose of the Study:

• * To present lessons learned from the Subglacial Lake Ellsworth (SLE) drilling campaign's equipment failures.
• * To outline viable technical options and operational procedures for future clean access to deep subglacial targets like SLE.
• * To improve the success rate of subglacial exploration through shared knowledge and refined methodologies.

Main Methods:

• * Analysis of equipment failures and operational issues encountered during the 2012 Subglacial Lake Ellsworth fieldwork.
• * Review of experiences from other hot-water drilling programs and recent field testing.
• * Development of improved technical options and operational procedures based on lessons learned.

Main Results:

• * The Subglacial Lake Ellsworth (SLE) project experienced significant equipment issues in December 2012, leading to the abandonment of access holes.
• * A failure to connect with a subsurface cavity was a critical issue encountered during the drilling operations.
• * The study identifies key challenges and provides insights for overcoming them in future subglacial drilling endeavors.

Conclusions:

• * Past drilling attempts at Subglacial Lake Ellsworth encountered insurmountable technical difficulties, halting the project.
• * The collected data and lessons learned are crucial for developing more robust and successful future subglacial exploration strategies.
• * Refined hot-water drilling techniques and operational protocols are essential for accessing deep Antarctic subglacial environments.