What Geology Taught Me About Painting

Besides being an artist, I am also currently a geology student at the University of Texas at Austin. I have realized much of the skills used in geology have applications in art. Here I wish to break down how all of us can learn from the discoveries in geology.

Observation:

I believe the most important skill in art and geology is the same. And that is observation. Geologists must take their observations either from the field or in the lab and use it to make interpretations. After making that realization, I was struck by how similar this sounds to what artists do. As an artist, we take information we gather from our subject or reference, and interpret that information as a 2 dimensional representation on canvas. 

The first example I would like to show is looking at this piece of granite. Granite is very commonly found on continental crust. Many of you might be familiar with how granite looks, but I will go into more detail on how exactly to identify this as granite. First notice the size of the mineral grains, in this case the grains are large. This means the rock cooled slowly, so minerals are able to develop into larger crystal lattice structures. This usually also means the rock cooled beneath the surface. We call these rocks intrusive igneous rocks. Next we observe the mineral composition. Geologists must develop a strong visual library of how different types of minerals appear, both in a petrographic microscope and in a hand sample. As a general guideline minerals found in igneous rocks are typically black or green when they are rich in magnesium and iron, those are referred to as mafic minerals. More silicate rich minerals on the other hand can have a wide range of colors such as clear to white or pink, we refer to these minerals as being felsic. This is not the most ideal way to identify minerals, but will serve our purpose for now. Notice how much of this rock contains the more felsic minerals. In this case the most felsic mineral is quartz (the grains that appear somewhat translucent), which are essentially a 3 dimensional framework of silicate (sio42-) units bonded together covalently, meaning electrons from each silicon and oxygen atoms are shared. Another notable felsic mineral is orthoclase feldspar(the pinkish grains), which contains Potassium, Aluminum, and silicate. There are a few mafic minerals as well such as biotite mica (the black grains) and plagioclase feldspar (the white or milky grains). 

 Knowing if each mineral is mafic or felsic is very useful in understanding the rock. According to the Bowen’s Reaction Series, mafic minerals are the first to crystallize from magma or lava. So this rock likely crystallized in stages, crystallizing from most mafic to most felsic minerals. We can also learn that because of the abundance of felsic minerals that the magma that formed this rock had to travel through a fairly thick crust. As magma travels through the crust and cools, the most mafic minerals gradually crystallize out leaving a more felsic melt. This explains why granite is more common in continental crust and basalt, a more mafic igneous rock, is more common in oceanic crust.

The picture above was simply an image of my countertop. But I hope you realize there is so much to learn just from looking at this piece of rock many pass by without thinking much of, and this article was barely scratching the surface. But imagine how much we can uncover about earth’s history if we learn to observe properly and have knowledge to be able to interpret our observations.

Observations in painting:

Now I would like to bring this subject back to painting. In the painting above, the focus was to capture the lighting. So instead in this case it is important to observe how the light behaves in different areas of the landscape. Some helpful background information is that this scene was from Mount Evans about 4000 meters above sea level, it was an early afternoon in July and the latitude was about 40 degrees North. Based on this information, I can already conclude that the light will have to be coming from an angle, since it is in the afternoon the color temperature of the light would be relatively warm, causing some cool shadows. Because of being so far above sea level the air was very thin and visibility was far, so the effects of atmospheric effects were slightly diminished. These hypotheses were confirmed by observations on site. Another interesting observation was the reflected skylight making all the top planes cooler and reflected light from the ground making all the bottom planes warmer. This made it easier to define form. 

Now is the time to come up with an interpretation. The subject was so brightly lit it was impossible to capture the full range of values visible on canvas. So keying the painting effectively was crucial. Because the scene is backlit, it made sense to key up the shadows and allow the lights to be washed out. With this, the pattern of light versus shadow, became the most important element in this piece. Because the shadows are keyed to a relatively light value, there was a lot of opportunity to add in reflected lights without breaking the light and shadow pattern. 

There are many different valid interpretations of the same subject. For instance, I could have zoomed in on the top left corner, or used a completely different color scheme or key. What is important is that these interpretations come from observations. Oftentimes preconceived ideas get in the way of properly making observations. We should always observe with an open mind in order to get the most out of our observations.