Geraldton-Onaman Transect Update
with Metal Earth Research Associate, Zsuzsanna Tóth.
Image: MacLeod Cockshutt Gold Mine (~1934). Source: Harry Fisher, Greenstone Public Library.
The Geraldton-Onaman transect covers the northern part of the metasedimentary Quetico subprovince, the Beardmore-Geraldton and Onaman-Tashota greenstone belts of the eastern Wabigoon subprovince. Orogenic gold deposits across the Beardmore-Geraldton belt produced over 4.1 Moz Au over the past century and significant resources remain (e.g. Hardrock deposit, Geraldton, ca. 6.4 Moz) in this belt. In others parts of the Quetico and eastern Wabigoon subprovinces, significant base and precious metal deposits are yet to be discovered.
Therefore, the Geraldton-Onaman transect is considered one of the poorly metal-endowed transects of Metal Earth.
Understanding the geological evolution of our transect and comparing it to that of the well-endowed Abitibi greenstone belt is a crucial step in explaining the spatial and temporal distribution of base and precious metal deposits worldwide.
The Geraldton-Onaman crew is starting its second field season this summer.
The team will primarily be studying the northern part of the transect focusing on igneous and sedimentary rocks. At the end of the 2nd year of transect research, all field observations will be compiled with geochemical, geochronological and geophysical data from the study area.
“If you look at the extent of the eastern Wabigoon subprovince, it is stunning to realize how a significant portion of it has barely or never been studied. It is quite amazing when you are among the first few people who are interested in studying certain lithological assemblages and the related research questions. We are looking at the area from a deeply scientific point of view and focusing on the geological processes that contributed to the development and evolution of the eastern Wabigoon and Quetico subprovinces between ca. 3.5 and 2.6 Ga."
"We need to complete a 4D puzzle spanning several hundreds of millions of years and a vast area. Due to the understudied nature of the eastern Wabigoon subprovince, our research is ground-breaking science.”
- Zsuzsanna Tóth, Research Associate.
Understanding the evolution of the Geraldton-Onaman area
“The evolution of these protocontinents is complex. The nucleus of the eastern Wabigoon subprovince is close to 3.0 Ga old but there is evidence for inheritance from even older pre-existing continents in the area. Volcanism was intermittently active for at least 250 million years, from 2.97 Ga to ca. 2.72 Ga.
– Zsuzsanna Tóth, Research Associate.
"Subsequently, the Quetico subprovince evolved as an accretionary prism along the southern boundary of the eastern Wabigoon subprovince over roughly 40-50 million years. The more we learn about the geology of the Geraldton-Onaman area, the more we realize that its history is very complex and how much we don’t understand about it.”
“What’s also interesting is that the Quetico subprovince was formed by the collision of two continents. The approach of the eastern Wabigoon and Wawa terranes drove erosion and the accumulation of the sedimentary rocks that make up the Quetico subprovince. But this is just part of the story. Along the boundary between the eastern Wabigoon and the Quetico subprovinces is where we find the gold. The tectonic activity, such as the accretion of the Quetico metasedimentary succession against the southern front to the eastern Wabigoon subprovince, is a key driving mechanism for the formation of the gold deposits.”
– Zsuzsanna Tóth, Research Associate.
Research Questions include:
- How did the eastern Wabigoon and Quetico subprovinces form and evolve?
- What type of geodynamic processes explain the accumulation of the volcanic packages?
- What deformation and metamorphic events affected the plutonic, volcanic and sedimentary rocks?
Zsuzsanna is from Esztergom, Hungary and completed her PhD at Laurentian University and MSc at Eötvös Loránd University in Budapest, Hungary. Her research interests are in Precambrian geology with a focus on structural geology, economic geology, igneous petrology and detrital zircon geochronology.
Keaton is from Mississauga, ON and completed his MSc at Laurentian University. His research interests are in volcanology, economic geology, tectonics and Precambrian geology.
Anna Haataja, MSc Candidate
Anna is from Airdrie, AB and completed her BSc at the University of Calgary. Her research interest is in metamorphic petrology.
2nd MSc Candidate, Position to be filled