Episode 12: Ore Deposit Structure - The Key to Value

Even before plate tectonic theory, economic geologists knew there was an association with ore deposits and geologic structures. Nowadays, most successful exploration companies understand the importance of understanding structural controls of an ore-forming system and incorporate structural geologists in their exploration programs. 

This episode of Discovery to Recovery focuses on the regional tectonic and deposit-scale structural controls on ore deposition, specifically on volcanic-hosted massive sulfide, epithermal, and Carlin-type gold deposits. If you have ever wanted to know the answer to the following questions, have a listen!

1.     What tectonic environments are most favourable not only for formation of an ore deposit, but for preservation?

2.     How important is it to understand post-ore modification?

3.     What are the local structural controls one can look for to vector towards and ore-forming system?

4.     Can you make discoveries without a fundamental understanding of structure? 

Our three speakers discuss structural controls from the regional, tectonic scale down to the prospect scale, answering these questions and more. Rodney Allen of Volcanic Resources discusses in detail how volcanic-hosted massive sulfide deposits are formed and the post-ore structural evolution that gets them to where we find them today. He also teaches us how to look for the most favourable stratigraphic horizon within a VHMS district.

Julie Rowland discusses the structural controls on epithermal deposits using examples from her home country of New Zealand, comparing and contrasting different styles of epithermal mineralization. She discusses both fossil systems and modern analogues for epithermal systems, and teaches us how to understand local structural controls when exploring for epithermal deposits.

Lastly, Moira Smith of Liberty Gold provides her expert insight into Carlin-type gold deposits, and why their structural interpretation is so important. She goes into detail on the shelf facies Carlin-type deposits outside of the main Carlin trend in Nevada, and compares and contrasts the two regions with respect to tectonic setting and local structure features.

All three speakers tell a fascinating story and all stress the importance of understanding structure and keeping an open mind.    

Theme music is Confluence by East Winds. www.eastwindsmusic.com