Talk
Mountains graphic with white diamonds on itGeoscience and Exploration

Lost But Not Forgotten: Recovering and Compiling Historic Datasets to Advance Modern Exploration in the Pine Point Mining Camp, Pine Point, Northwest Territories, Canada.

Thursday, November 21, 2019 - 9:20am to 9:40am Theatre One
(Student abstract)

Author(s)

Z.C. McDougall (Presenting)
University of New Brunswick
R. Adair
Osisko Metals Incorporated

Over the last few decades, digital data management and compilation have become essential to exploration and mining ventures. A significant impediment to mineral exploration is the lack of raw digital data from previous surveys resulting in significant re-work, financial burden and time delays.  The closure of Cominco Ltd.’s operations in the Pine Point Mining Camp happened at the very edge of the digital age in the late 1980s. At this point, over 20,000 drill holes had been recorded on analog magnetic tape for long-term storage. In addition to the magnetic data, approximately 1 million meters of core were left abandoned in a reasonably organized lot. Using this existing data, Osisko Metals Incorporated has recovered, categorized, and initiated the verification of mining and exploration data collected over half a century.  This dataset has been cross-referenced with physical locations and, in some cases, preserved core and logs. Site geologists now have access to exploration and production drill hole data spanning 50 years. By reviewing and enhancing this database, geological interpretation can be significantly improved and revised.  Historic collar surveys are within 5-10m of their true location on modern coordinate projections. To further validate and enhance the quality of the database, the historic collars in key areas are being re-surveyed with a Differential Global Positioning System (DGPS) tool, able to determine actual location with cm-scale accuracy. Due to the limited recovery and storage of geological information in the magnetic tapes, the database is being substantially augmented by a high-volume historic core re-logging program. The cataloguing of the affectionately named “Core Graveyard” has resulted in a digitally preserved core library where the locations of each stored hole as well as the relative condition are known. This catalogue allows geologists to target orphaned drill holes and search the core for mineralization or favorable ground in context of modern interpretations. In many cases, the preserved core can be used for reconnaissance of target areas based on mineralization trends or geometries. Incorporating the recovered logs into GIS and data processing programs, many obstacles present with transcription and interpretation are removed. The most important uses for these datasets are advanced 3D modeling of new data with recovered old data, validation of historical data, and recalculation of Mineral Resource Estimates. Furthermore, developing new exploration targets is therefore based on the identification of new controls on mineralization, leading to potential new discoveries. By integrating these crucial aspects, a workflow can be created for evaluating and drilling promising targets. Work to extend known deposits begins with visualizing historic drill hole data in GIS/3D GIS programs. Positive results can be followed by determining which holes should be reviewed from the Core Graveyard, including re-logging, resampling or extending sampling intervals. Re-logging of historic holes focuses on: highlighting depth to target, mineralization type(s), horizons of interest, and identifying under explored or undervalued areas that show promise for new drilling targets. This approach has now been tested at the Pine Point property with promising initial results, which will be further explored in the future.