GeOCHemISTea

This is a different conversation from those we’ve had before because we took two extremely different topics in hydrogeochemistry and pXRF on drillcore and looked at how these different techniques and scales come together in a junior exploration program.

If you've never been to Nevada, no worries... we're going there together, now.

A favorite thing Dave likes to say is "we do all sorts of things to the rocks... to try and understand them...." But then Dave often likes to tell geologists and especially mining engineers that "rocks don't give a shit to what we think of them. They're just rocks. They're just gonna sit there and be like, all right, whatever guys. I'm a rock."

And as for why you won't see Dave penning a book on his career... "because it with be complete utter bullshit." That's hindsight bias for you.

Join us as we discuss Nassim Nicholas Taleb's philosophical book "Fooled by Randomness" and try and apply it to the wide world of geochemistry... with drinks.

For this episode we read the Datarock blog post Fusing core imagery and chemistry to model stratigraphy.

Perhaps more interesting that the foundation of Datarock is built on Aussie rules football is some of the advice that Brenton Crawford, one of the the company's founders has to impart: that we can get distracted by what we 'need' from a university in order to get the geoscience job we want. He goes on to counsel that getting involved in a community of your choosing, albeit geochemistry, data science, or some other sector, can be a better investment of your time and energy. Importantly, if you have interested in transitioning to data science, remember that your knowledge of the geosciences is infinitely more important than an additional degree in data science - your ability to make an impact on your team is greater simply because you understand the nuances of the data you are working with.

As for working with image data and integrating it with geochemistry... you'll have to have a listen.

For this episode we read: Geochemical Modeling of Water-Rock Interactions in Mining Environments (Alpers and Nordstrom, 1997).

For those who've asked "how do I become an environmental geochemist?" ...Tom has some advice for you. And for those that have questions about the business of consulting... his tea has some hard numbers. Best, though, is when we examine geochemical modeling philosophy and the Alpers and Nordstrom quote that models are "not reality, nor [are they] reliable, correct or valid representation[s] of reality."

After this show, I think we need to interview some more environmental geochemists!

For this episode we read: "Laser-Induced Breakdown Spectroscopy – An Emerging Analytical Tool for Mineral Exploration (Harmon et al., 2019)"

Starting from the basics of what is LIBS through to cutting edge applications, Andrew Somers (Global Business Director: Geochemistry at SciAps Inc.) is here to guide us through the ins and outs of this tech. 

For our young geochemists - are you nervous about making the jump from working at a mining company to working for a vendor? Andrew has some words of wisdom on this too. 

What are we observing versus what are we supposed to see, in other words, how (and how much) is dogma directing our interpretations? We explore this concept this month when we delve into Duncan McLeish's PhD work on the transport and deposition of gold at the Brucejack Deposit (Canada). 

In a world where aqueous complexation has long been considered the only viable means of transporting gold to depositional sites in hydrothermal ore-forming systems, Duncan et al. found that rejecting dogma was of the utmost importance. For example, a major weakness of the Au transport in solution hypothesis is that it cannot readily explain the formation of ultrahigh-grade gold veins when transporting Au at ppb levels.

...so how do “bonanza” veins contain weight-percent levels of gold in some epithermal and orogenic deposits?

...what are colloids and flocculation?

...why is this research both exciting and important? 

All this and more in this episode! Put on your thinking caps, it's time to listen to some applied chemistry, economic geology and a little bit of philosophy. 

For this episode we read "Colloidal transport and flocculation are the cause of the hyperenrichment of gold in nature" by McLeish et al., 2021. 

Did you know that in addition to being one of our industry's geochemical powerhouses, JC is also an artist? But also as we continue along in the episode we'll see that he's perhaps a staunch businessman. 

For this month's episode we reviewed a PDAC short course organized by JC and Lynda Bloom entitled: "Geochemical Modeling for Orebody Knowledge and Exploration Targeting Workshop" - including his helpful Review on Methodologies for Geochemical Data Analysis. The course spans fundamentals (including QA/QC), a review of methodologies, interpretation of 4 acid ICP data, geometallurgy, ore body knowledge, regional soil geochemistry, and applications of till and indicator minerals in glaciated geochemistry. The idea is that as geochemists we need to move past just exploration and into the realms of mine, mill and reclamation. If we have geochemistry collected at any point, by any group it must be standardized as a true multi-client dataset. Sample the overburden! Have a geochemist overseeing your database and controlling how the rocks are sampled from a multiclient perspective. "Until we do this, geochemistry will never be looked at in a company as a valuable asset, but as an expense." 

As a sidenote, JC's section of the course contains topics, such as compositional data, geochemistry templates, and unsupervised and supervised learning. Buckle up geochemists and geochemistry enthusiasts... see you on the other side of this fascinating interview! 

Article: Random forest rock type classification with integration of geochemical and photographic data (Trott et al., 2022)

Do you want to integrate machine learning into your exploration workflow, but feel precluded from doing so because of complicated terminology in the majority of the literature? Have a crack at Mac's first paper and then join us for this discussion on how he implemented a relatively simple, but well-constrained, study to provide explorationists with confidence on joining the ML push towards making core logging more quantitative. 

For our young listeners, Mac has some twists and turns on his way towards his current position as a PhD student at Queen's as well as being an embedded researcher at Goldspot. 

Also... the tea is good. 

Have you perused a geochemistry lab schedule and not known where to start? Don't worry - the answers are not obvious and GeocHemiSTea is here to help! 

We have broken this episode into six sections to get to your answers quicker, but considering the complexity of the topic and the importance of having the best data possible we recommend listening to this episode in its entirety!