talk
Diamond Geology and Exploration

Direct Discovery of Concealed Kimberlites with Microbial Community Fingerprinting

Tuesday, November 20, 2018 - 11:40 to 11:59 Theatre 1

Author(s)

B.P. Iulianella Phillips (Presenting)
Mineral Deposit Research Unit, The University of British Columbia

R.L. Simister
The University of British Columbia

E.M. Cayer
The University of British Columbia

P.A. Winterburn
Mineral Deposit Research Unit, The University of British Columbia

S.A. Crowe
Mineral Deposit Research Unit, The University of British Columbia

Mineral exploration in Canada is becoming increasingly complex as the majority of undiscovered commodities are likely deeply buried beneath significant glacial overburden and bedrock, reducing the effectiveness of many existing tools. The development of innovative exploration protocols and techniques is imperative to the continuation of discovery success. Preliminary experimentation has demonstrated the potential viability of microbial fingerprinting through genetic sequencing to directly identify the projected subcrop of mineralization in addition to the more distal entrained geochemical signatures in till. With the advent of inexpensive modern sequencing technology and big-data techniques, microbiological approaches to exploration are becoming more quantitative, cost effective, and efficient. The integration of microbial community information with soil chemistry, mineralogy and landscape development coupled with geology and geophysics propagates the development of an improved decision process in mineral exploration.

Soils over porphyry, kimberlite, and VMS deposits have undergone microbial community profiling. These community-genome derived datasets have been integrated with trace metal chemistry, mineralogy, surface geology and other environmental variables including Eh and pH. Analyses of two kimberlites in the Northwest Territories show significant microbial community shifts that are correlated with subsurface mineralization, with distinctive microbial community profiles present directly above the kimberlite. The relationship between microbial profiles and mineralization leads to the use of microbial fingerprinting as a method for more accurately delineating ore deposits in glacially covered terrain. As databases are developed, there is potential for application as a field based technique, as sequencing technology is progressively developed into portable platforms.