By Kilani Muhammed Olakunle
Following a viral video showing people at Olorunsogo Local Government Area, Igbeti town about 93 km to Saki, my hometown observing a rock peeling off and emitting sounds interpreted as cries for help, I urge the public to stay calm and keep a safe distance. There is nothing spiritual about it. This is a natural geological process known in geography as rock exfoliation, a form of physical weathering.
What is Weathering?
Weathering in a simple term referred to as breakdown of rock from its original value or shape into smaller pieces, influenced by certain natural parameters. These parameters act like agents, driving the process, which occurs gradually over time not just overnight as you see right now in Igbeti.
- Within the rock, internal stress is caused by repeated heating and cooling, water infiltration, and other natural forces build up over several months or years. Eventually, these stresses cause the rock to break apart, a process known as weathering.
Do you want to know its type?
Weathering is broadly classified into three types:
Physical, Chemical and Biological Weathering. The physical usually occurred as a result of physical forces which could be attributed to either;
1. Frost wedging where water enters cracks in rocks, freezes, and expands them thereby allowing the rock to break apart.
2. Thermal expansion stylishly takes its own cause when there is a repeated heating and cooling which makes the rocks expand and contract, eventually cracking.
3. Exfoliation occurs when layers of rock are peeled off due to pressure release.
The agents (drivers) of physical weathering include:
Water, Wind, Temperature, Ice, Living organisms, Carbon dioxide and Oxygen.
These agents are necessary for weathering to occur. Without them, the process cannot begin.
To explain this in simple terms:
During the Sallah period, people often eat more meat than usual. It may take 1–2 days before digestion is complete and one visits the toilet. When the time comes, you may feel internal pressure, struggle a bit, and finally release waste. In this analogy, the meat is the agent of the internal driver of the external action.
Similarly, what recently happened at Iyamopo Hill in Igbeti, Oyo State, is not spiritual. The hill has experienced long-term heating during the day and cooling at night. Over time, this caused the rock layers to expand and contract. The peeling people observed is a result of internal stress being released.
Geographically, this is known as exfoliation which is a classic case of physical weathering.There’s no mystery here at all, it is just a science.
This phenomenon should not be surprising to Senior Secondary School students or Geography undergraduates. We have long taken students on excursions from their first year through to 400 level to observe real-world applications of what is taught in class.
This is an educational opportunity. Institutions in Oyo State and surrounding areas should use this site as a field study location. It’s not just about visiting, it’s about studying the:
1. Rate of exfoliation over time
2. Contributing factors
3. Potential impacts on local residents
4. Ways to mitigate hazards
Whether or not government funding is available, we can do better as a scientific community.
I welcome collaboration from researchers or Institutions interested in studying this geological event. Let’s deepen our understanding and use this opportunity to educate the public and future geographers.
Olakunle is of the Department of Geography and Environmental Management, Ahmadu Bello University, Zaria and could be reached through kilanimuhammed786@gmail.com
