Air reverse circulation at the hole bottom in ice-core drilling

• Published in: Journal of Glaciology
• Main Authors: ZHENGYI HU, PAVEL TALALAY, ZHICHUAN ZHENG, PINLU CAO, GUITAO SHI, YUANSHENG LI, XIAOPENG FAN, HONGMEI MA
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press 2019
• Subjects: ice coring; ice engineering; polar firn; Environmental sciences; GE1-350; Meteorology. Climatology; QC851-999; ice core; Journal of Glaciology
• Online Access: https://doi.org/10.1017/jog.2018.95; https://doaj.org/article/424efc6fcdf846b9a36e01f0e3b0fd47

Ice-core drilling to depths of 200–300 m is an important part of research studies concerned with paleoclimate reconstruction and anthropogenic climate change. However, conventional drilling methods face difficulties due to firn permeability. We have developed an electromechanical ice-core drill with air reverse circulation at the hole bottom. We believe that the new drilling system will recover ice cores faster than shallow auger drills, with high efficiency and low energy consumption. The theoretically estimated up-hole speed of the airflow should be not <7.7 m s−1 to allow proper removal of ice cuttings from the borehole bottom. The computer simulation and test results showed that the design of the new ice-coring drill is feasible. The maximum allowed penetration rate depends by square law on airflow.