Brett Davis’ Post

Is being critical a fault? Ok, a poor pun, but a lead-in to this post where I am mildly critical about a recent post regarding a fault. Recently, a colleague posted the photo below, with the comment ‘share your thoughts’. Apart from my view that this is a lazy trend that is developing, because people are starting to do this without offering any information or interpretation of their own, I was intrigued to see the replies. They can be distilled down to the contents of five comments. Five people said the photo contained a normal fault. Two made the additional comment that it was extensional, and one noted the presence of shear gouge on the fault plane. That’s it. For me, this showed a lack of critical review, because there were questions posed by the geology, some of which I have illustrated in the annotated view of the photo and listed below. Is this really all we can say about this photo? Have people thought about the implications of a change in dip direction, which change the fault from apparent normal to apparent reverse? So, which is it? If the dip changed then that regime could be interpreted as contractional as opposed to extensional. Failure to acknowledge that steep faults commonly change dip direction (so do low-dipping faults) can attribute the wrong tectonic environment to a volume of rock. This can seriously affect how we think about the evolution of an area, what mineral deposits may be present etc. Why did no-one mention the presence of possible hydrothermal mineral deposition and possible weathering products of sulphides? Wouldn’t this be critical if undertaking exploratory assessment, let along just trying to do a complete documentation of the structure. And why do people assume the fault continues? The continuation of the structure at the bottom of the photo is really hard to see, yet there appears to be iron staining parallel to the layering. Has the fault drastically changed orientation? If so, how can it be reverse or extensional? Good geology practice means teasing as much as we can out of an outcrop. Faults are more than planes of displacement that have a constant orientation. We need to do better.

Just what we need in exploration - a mechanical chicken that can shuffle through the leaves in a trench to see how many snakes are lurking there. Or to walk potential minefields when exploring in conflict zones. Or for distracting a bear in the Canadian wild. Or any other number of safety-related tasks associated with the jobs that brave geologists do when they don't have a mining engineer who is surplus to requirements.

Here are a few comments on the role of competency contrasts with regard to rock deformation, permeability creation, fluid flow and hydrothermal mineral deposition. The importance of this phenomenon is intermittently recurrent within my LinkedIn feed, with contributions from people such as Ashleigh Ball and David Rhys (check their past posts for some great photos and content) and others. This is not an exhaustive coverage of the topic - just a few comments and photos to sponsor discussion and that are a prelude to an intended larger document that will be compiled as time permits.

For people who haven't seen this, here is a re-post of a topic by Jun Cowan, which discusses AI and the peer review process of published articles. It's an issue that will continue to be a problem until it becomes too sophisticated for us to identify. For the moment, though, the issues are something that basic peer review should identify and that people garnering an editorial role should be making an effort to capture and deal with. Unfortunately, editorial roles are not generally something people aspire to, so there's not a lot of competition once people get in. As such, there is a bell curve of ability and care for the role, ranging from excellent to well short of par. For many editorial positions it's attrition and death that see the introduction of new people to the roles, and contributors sometimes have less than ideal experiences when submitting articles. One of my worst experiences came from having a paper under review for 5 years, due to a special volume editor that really didn't care. Peer review is necessary and there has been more good than bad, but it's never been without issue or bias. Papers-for-the-boys has always been rife, with preferential acceptance of publications of one's mates. But, there's no doubt been an incredible amount of dodgy science that has been captured and rejected. Another issue is that it is hard to find reviewers. Everyone wants to cite a paper or see their name in print, but very few want to take the trouble to review them. So, hasty reviews or non-reviews infect the process. And then we have the proliferation of items that get published without peer review on public platforms like LinkedIn (I plead guilty), or that get presented at conferences etc. Ultimately, the onus is on us to maintain our own vigilance and critical review of material put in front of us, because it won't always have been vetted professionally prior to our viewing.

This week I had the pleasure of Mark Gabbitus (IMDEX Ltd Head of Product) hosting me for a tour of IMDEX’s Balcatta facilities and getting a demonstration of their new ACTx digital core orientation tool and its spouse, the Smart Jig (yes, every gizmo, device, and gadget must have a name). This post is a summary of how the device works and my assessment of it, coupled with my usual rants about core orientation. As an aside, I had no idea just how much infrastructure, technical expertise, R&D etc goes on behind the scenes at IMDEX. It is truly impressive.

Can any of my colleagues give me insight into how these structures form? They are from the island of Pag, Croatia. They are not my photos - they were shared with me by a colleague who was curious as to what they represent. Are they part of some sort of karst process?

Over the years, since I took on the helm of geology editorship with Coring Magazine, there have been some true geological heavyweights who have been gracious enough to endure my interview questions and give very informed perspectives on careers as geologists in academia and industry. These people have included Beau Nicholls (Sahara Natural Geosciences), Addepalli Kasiviswanadham (Vedanta Exploration), Sarah Jones (SJGeology), Richard Tosdal (PicachoEx LLC), David Rhys (Panterra Geosciences), Greg Hall (Golden Phoenix International Consulting), and Nick Tate (Geomap). The current issue of Coring maintains the high standard of interviewee, with insight from Dr Frank Bierlein. Very few people can boast a career as stellar as Frank’s, with over 150 peer reviewed academic articles alone, in addition to a protracted industry career. There are some real gems in the answers Frank has provided to my questions, so do yourself a favour and have a read!

Kris Butera is MD of Plutonic Ltd, a company exploring a large epithermal field in the Northern Territory. In the current issue of Coring Magazine (Issue 26) Kris uses his own unique and very readable style of prose to describe the project geology and the reasons he is so keen on the area. In his words, 'we now know there’s a near endless arena of low sulphidation epithermal veins, porphyry geochemical and alteration footprints, advanced argillic alteration forming topography to guide us to the interesting systems, breccia fields, geyserites, silica caps, lithocaps, skarns.' Do yourself a favour and have a read! 

Issue 26 of Coring Magazine is out and petrographic guru Rowena Duckworth has provided details on several drill core scanning techniques. This is something that many of us hear about, and that we see a lot of LinkedIn traffic about, but many of us know little detail about. So, here's a short, interesting article that fills in a bit of the detail.

Issue 26 of Coring Magazine is out! Here's one of the articles, this one from the one and only John Anderson.