Andrew Steiner

MSc Geological Sciences

ESB 4047
graduate

My research concerns the hydrological system responsible for the formation of Carlin-type Au-deposits (CTGDs). Recent discoveries of CTGDs in basins around the world have increased interest in these large, high-grade deposits. Despite their economic significance, the genetic model for these deposits is still debated, with both amagmatic and magmatic sources of fluid and metals proposed. Amagmatic and magamtic-hydrothermal systems vary in scale, fluid flow directionality and temperature gradients, and as such provide means to test the validity of genetic models. An in depth understanding of the hydrological regime responsible for CTGD genesis is essential for understanding the critical geological criteria required for their formation.

My MSc thesis is focussed on CTGDs in the Nadaleen trend, Yukon, under the supervision of Ken Hickey. I am studying the components of the auriferous hydrological system to try and improve the existing model for hydrological models in CTGDs. This includes ore-fluid controls, heat advection patterns and determining the relative timing of mineralization. A preliminary geological and structural study was undertaking over 5 months of field mapping and core-logging to understand the geological framework of the deposit. This included a deposit paragenesis study using petrography, cathodoluminescence, LA-ICP-MS, EMPA and XRF to determine chemical and textural differences between various vein, deformation and mineralization stages. Auriferous fluid pathways were identified using gangue mineralogy, trace element lithogeochemistry and fluid-buffered stable isotopic signatures. The main method for determining temperature is the emerging technique of clumped isotope thermometry, used in tandem with apatite fission track and U-Pb geochronology to constrain the T-t history of the deposit.

BSc (Hons) University of Glasgow, Scotland, 2013-2017

Papers:

Koehn, D., Steiner, A. and Aanyu, K., 2019. Modelling of extension and dyking-induced collapse faults and fissures in rifts. Journal of Structural Geology v. 118 (21–31), p. 21-31.

Steiner, A., Hickey, K. and Coulter, A.B., 2018. The structural framework for Carlin-type gold mineralization in the Nadaleen trend, Yukon. In: Yukon Exploration and Geology 2017, K.E. MacFarlane (ed.), Yukon Geological Survey, p. 139-149. http://data.geology.gov.yk.ca/Reference/79505

Coulter, A. B., Lane, J., and Steiner, A., 2018. Osiris cluster Carlin-type gold, east-central Yukon. In: Yukon Exploration and Geology 2017, K.E. MacFarlane, (ed.), Yukon Geological Survey, p. 65-74. http://data.geology.gov.yk.ca/Reference/79493