Why geology

Rocks in my head

Geology is a profession that is full of foreign concepts for most people. It’s an esoteric artform practiced by people who think in millions of years and speak another language.

So.... why geology?

Geology is the study of the Earth. From rocks and minerals to the structure, evolution and composition of the planet.

The principles of geology are also needed for the study of other planet bodies, like Mars or the Moon. The forces that shape our planet can be recognised in other rocky planets.

Sources: Earth, Google Earth; rocks, A.Reid.

Why do we need geology?

Mineral and energy resources are the cornerstone of why geology developed. The first modern, scientific geological maps were made in England during the industrial revolution as people realised that the coal seams they were working were more extensive than just the local patches of coal, and that in fact the Earth had laid them out in great planar sheets – beds they were called – that wound up and down the country and occurred in predictable and repeatable orientations.

The need for coal would initiate western scientific study of rocks that led to the discipline of geology. Soon, as more metals were demanded by society as technology and consumer capitalism began to grow, a whole raft of new materials were required to be extracted from the Earth in increasing volumes. Metals like iron, copper, nickel, zin, lead were needed to manufacture the items used in people’s daily lives.

The list of elements we need keeps expanding.

Who could have predicted that the elements lithium or cobalt, or niobium and the other rare earth elements would become household names in the last 10 years? Who would have thought that they would be discussed around dinner tables as the news filled our screens of the ever-increasing demand, geopolitical implications of which countries have supply and which have demand, and the dangers that demand is placing on our environmental and societal well-being?

Energy is similar.

Our complex society has evolved because we have had access to cheap, abundant and rich sources of energy in the form of fossil fuels. First coal, then oil and gas. These three have become the foundation for our society to the extent that the fate of entire nations have been decided based on rocks.

The great sedimentary rock systems that spread out across the Middle East contain remnants of microorganisms that once filled highly productive warm oceans from hundreds of millions of years ago. The algae and microorganisms of those oceans died, sank to the bottom of the sandy ocean floor only to be buried by layer upon layer of younger sediment and heated up in the process. The heating effect of the burial caused their cellular structure to break down into more simple molecules and the hydrocarbons that were formed in this way came to be the liquid energy that fuels our cars and is processed into our plastics.

Groundwater, climate studies, civil engineering: three other examples diverse disciplines that incorporate geology, or geological knowledge, of the many others.

Sources: Turbines, EV, Wikipedia commons. Dry lake, A.Reid.

Geology is also associated with hazards.

Volcanoes and earthquakes are the most visible manifestation of geological hazards and they are largely the reason behind the axiom that “civilisation exists by geological consent”. Landslides, sinkholes and tsunamis are all hazards related to Earth processes.

In regions where the earth’s great tectonic plates collide or pass each other by, volcanoes and earthquakes can be the most troubling manifestations of the power of the Earth itself.

No need for the atmosphere to be involved in these processes, the deep restless energy of the Earth’s hot interior comes to the surface here and causes magmas to erupt or faults to grind together.

There are very important questions that geologists ask daily around the world as they monitor the latest eruptions in Iceland, or the movement of faults beneath Indonesia, New Zealand or Japan. How significant are these faults and are they likely to be active? Parts of the world where earthquakes are a hazard need to know this type of geological information for planning and risk management.

Sources: Volcano, Wix; geologists, A.Reid; gas rig, ABC News

Overview effect

Practical concerns aside, geology also helps us understand the story of the Earth itself.

There is an inherent beauty in the natural world that we have understood since time immemorial. Nature is our home. From the Earth we are born, and to it we will return. There is a grand, universal majesty in our deep connection with the Earth, on a very physical, very primordial level.

Our bodies are built from the molecules that we ingest from our environment.

Calcium in our bones once cycled through magmas into minerals like feldspar, were then uplifted, eroded and washed into the oceans where they were deposited in sedimentary rocks. Those sediments became incorporated into the continents by the force of massive tectonic plates colliding and finally those sediments were eroded and worn down into the soils that we now grow our crops on and feed to our livestock.

The milk we drink contains calcium that has been through the rock cycle.

The deep time aspect of geology remains the most fascinating part of the entire science for me.

I have worked in laboratories filled with expensive mass spectrometers, highly sensitive instruments that can measure the most minute abundance of different chemical isotopes, the subtle variation in the proportion of which can tell us the age of the mineral those isotopes are contained within. It is so exciting to find out the age of a rock in this way; finding out something no one has ever known before.

There are also the wonderful times as a geologist that involve being out in nature, surrounded by rocks in a place geologist typically call “the field”.

A geological skill is to recognise different rock types and to be able to place them on a map, so that other people can know what rocks are where. By this process, a picture can emerge that describes the spatial arrangement of related rocks. It is then up to the geologist to understand the process or processes by which those rocks came to be arranged in that way.

While a lot of geology can be done remotely, there is nothing like being able to stand on an outcrop and look out across a valley, across a mountain landscape or across a vast outback plain and visualise the powerful tectonic processes that left their mark on the rocks and landscape that we observe today.

Vancouver, a glacial-human landscape. Photo A. Reid

There is something sublime about this type of contemplation. A Zen-like state perhaps that, for me at least, induces powerful reflection on the brevity of human life, the narrowness of human timescales, and the insignificance of our human troubles at the scale of the planet.

This is a type of overview effect, similar to what astronauts experience.

It is a powerful antidote to feelings of partisan, tribal rivalry.

Understanding Earth and our place in it is foundational to our very survival, especially in these times of global uncertainty.