The Role of Geologists in an Unconventional World

In my career, it’s been too easy to think that geologists have little to no role in an unconventional world beyond geosteering. We put the hole in the ground and let the engineers deal with the rest. The more I’m exposed to the full lifespan of a well, the more I wonder if we’re bounding ourselves too tightly.

Since the dawn of oil, the geologist’s role has been finding the oil and making sure the wellbore gets put where the oil is. In many of our unconventional reservoirs though, the oil is practically everywhere, but we still high grade one (or several) 10’ to 20’ drill windows where we think the rocks have the most oil, or where the well has the best chance to produce the most oil. I think we've assumed that the one leads to the other, but in my experience in the Niobrara, percentage in zone has relatively low impact on production. You can’t pick out which wells were in zone the most or not based solely on production, but we also have several hundred feet of rock that we know has economically producible oil, or is connected by faults to economically producible oil, so even if we're out of "zone," we're still on oil. As such, I've been wondering how dependent greatest production is on that 10' to 20' window we're so focused on.

Obviously, some pay zones are still very narrow, and you’re operating within that 10’-20’ window because that’s the only place you can put your well without insanely poor economics or without losing the hole. In the circumstances where wellbore stability is an issue, well location isn’t a matter of maximizing oil, but maximizing hole stability, so in that circumstance, we already recognize that, no, maximizing oil isn’t the only thing that dictates where we place our well. We need to consider drill conditions, but we usually then go right back to optimizing oil volume, even in reservoirs where we don’t have any hard data to indicate that’s necessary.

But it’s job security, right? If we say, “Well, you don’t really need to put it anywhere specific. Just drill a good hole, and we’re set,” we’re signing our own pink slips. Fortunately, I don’t think it’s that easy. In fact, I think we’ve been over-simplifying the whole thing, which is understandable. I’m a big proponent of K.I.S.S., especially in the beginning stages of something and when we can get away with it, but horizontal drilling is not new anymore, and can we get away with K.I.S.S when it comes to wellbore placement and design at $45/bbl oil?

Should we consider redefining the “best” rock to include the full life of the well? After all, we drill the well, then we frac the well, then we produce the well. Eventually, we P&A the well. In reservoirs where we can, should we consider all those phases when we’re planning our wellbore placement? For example, the rocks that we think contain the “most” oil might not be that great for drilling and frac’ing. Or maybe it’s fine for frac, but then there are corrosion issues while producing. Can we use well placement to improve all life stages of a well and truly maximize the ROI of that asset?

Obviously, you need to know your company goals before you do this. What does “Maximize the ROI of the asset” even mean for your team? Does your company intend to sell to another company in the next few years, or are you in it for the (potentially) 20-year life of the well? Once you know these things, you can plan your development accordingly. Ask yourself if it’s time for that development to consider all aspects of the life of the well.

If the answer to that question is “yes,” we have our work cut out for us. We need to gather and collect data on all those aspects and consider the role the rocks might have played in it. Is a well corroding because the rocks have high Fe and Mg compared to other rocks in the reservoir? If you bump that well up or down, can you help that? What about getting pipe stuck in the hole because it’s too sinusoidal? Or maybe you need to purposefully plan sinusoids in your wellbore to take advantage of anisotropic permeability. Maybe your vertical perm sucks but horizontal perm is good, and planned sinusoids plus an optimized completion plan could maximize that, but then if you have two-phase flow in a well, you need to understand whether or not your sinusoids could create flow barriers or places for sand to collect during flowback and what could be done with that. When you start bringing other considerations in to planning your well, our role really starts to expand beyond finding the most oil-rich rocks. Should we consider the most frac'able rock also? What about the rocks that will corrode our well the least?

What do you guys think? Should geologists stick to considering ONLY where the most oil is when we drill the wells and let the engineers deal with everything else? Or should we work with our engineers and try to put the well in the best place possible for all life stages when possible? Which stage should be most optimized/take priority?

Are some of you already doing this, so this is old hat, and you’re shocked at this not so young geo who is just now asking these questions?