Engineering Tip: Be Skeptical of Models
Models. We deal with them all the time. Frac models, reservoir models, fluid models, models of models. Lots and lots of models. But models have two major limitations:
Inputs - Models are only as good as the data you put into them. If you have inaccurate or misinformed data, then your model is going to be inaccurate and misinformed. Every reservoir model requires porosity as an input. But porosity can change a lot across the reservoir. Often times we are using porosity from a core sample and extrapolating across the reservoir. It's better than nothing, but we need to be realistic about the potential inaccuracy this causes.
Understanding of the physics - The universe is a very complex machine. We like to take natural mechanisms and boil them down to one or two variables so that it is understandable. However, most things in nature are an interconnected web of many, many variables. Let's take fracture modeling. People love to reduce fracture growth down to a simple model of pressure and injection rates. In reality, there are a gazillion things that impact fracture growth. We love simple models that show nice, parallel, predictable frac wings, when in reality, we often get a spider web of fractures that grow in many different directions.
Models will always give you an answer. Whether or not that answer is accurate is a different question entirely.
And don't get me started on climate change models...
Please don't read this and think that I am anti-modeling. Models are a useful tool, but they are a tool and not an exact science. When you use a model, be a little skeptical of the results. Ask questions and compare it to other information and intuition that you have. If the model gives you something that seems unreasonable, dig deeper and ask more questions.
At the end of the day, human intuition and historical data can be just as powerful a tool as modeling. Let's not get too carried away with models.