by Elena Alganaeva, Consultant Geologist
Brownfield and greenfield exploration are often framed as distinct strategies shaped by company culture or market conditions. I propose that they are cycles within the same system that follow and feed one another, and this has serious implications for the industry.
Greenfield exploration surged in 1960–1990, driven by the post-war demand. That created a pipeline of deposits that fueled brownfield exploration in the subsequent decades. Money followed the lower risk, with little incentive to step far from known deposits. As the brownfield returns clearly diminish now, the stage is set up for another multi-decade greenfield wave.
If my thesis holds, a cycle of greenfields is coming in the next decade or so. But this time it will be different in one detail—lots of the unexplored land in stable jurisdictions is undercover.
Many see the solution to this in refining surface-based methods such as remote sensing, geochem, and machine learning. The toolbox is full and growing. All of this is undeniably useful. However, undercover exploration might require a mental leap first. Maybe there are only so many answers left on the surface; maybe it’s time to look deeper, literally and not.
You might not realize it, but we have seen this movie before.
The oil and gas industry used to drill hills in Texas. That was the exploration model in the early 1900s. Today, those are known as classical structural traps, specifically compressional anticlinoria and halokinetic diapiric domes. They didn’t care about any of that back then—any hill was a drill site. It was the most successful exploration idea in history.
By the early 1970s, the hills had been finished. The bright minds in oil and gas took a leap and proposed to explore passive continental margins. They went on and shot speculative multi-million-dollar seismic based solely on theory. There was no physical evidence, only reliance on the quality of neural interactions. And did I mention that all of that was offshore?
The shift from surface prospecting to conceptual plays was rapid in oil and gas. Passive margins, sequence stratigraphy, deltas, salt tectonics all became targets. The Exxon boys were serious—they weren’t playing.
Mineral exploration is bound to head down the same path—models will give way to understanding processes. Because there is no other path to take. This shift is like the path to mastery in art, moving from recreating the surface to seeing the form. You can learn how to make these four drawings, somewhat quickly, somewhat reliably.
But how do you go beyond these four? How do you draw a cat? Now, you need to see the structure of any subject. You must internalize how the form works. It takes years, but once you do—you’re free. You can draw anything.
There’s a similarity to exploration in that. When the template is gone, the only way through is to understand the underlying principles. After that, you are untethered from a diagram.
Take porphyries. The Andes have always been the model. But consider this: porphyries form when volatile-rich magmas de – compress. There is more than one scenario, sure, but tectonics may provide this trigger. Thick crust builds pressure, thinning crust releases it. Porphyries love tectonic shifts. What matters is the pressure path, which can be recreated in a range of tectonic settings. So, now you’re looking for the pressure path, not simply the Andes look-alikes. Enter Basin Analysis.
You then need to know which section of a strike-slip zone is more likely to produce that decompression trigger. Welcome to Structural. You need magma to reside longer in mid-crust and intrusions to ascend slowly. That’s Igneous Petrology. The real motherlode is tectonics though, but we are not treating it like one. Combining cross-discipline knowledge builds that meta skill in undercover exploration—thinking in processes, not analogs.
I feel the industry leans on the hope that a breakthrough technology will eventually arrive and solve it all. It probably plays well into a hope-as-strategy approach in many exploration campaigns. The ultimate tech for undercover exploration is going all in on geology and never looking back. The irony is that much of the toolbox already exists. At least it’s fair for structural plays, both tectonic and morphological. The science is there, behind the paywall, all scattered across papers and journals. It just needs to be taken, synthesized, cross-pollinated, questioned, translated, shared and applied, and then… we are halfway there.
For more information: Get in touch with Elena on LinkedIn
