Exact Answer: They Don’t Have A Lifespan, And They Never Die
Rocks are a big part of our world, and we use them for many things. We build buildings with them, pave roads with them, and even decorate gardens with them.
But how long do rocks live is an age-old question, and it might surprise one to know that some rocks can last for millions of years straight.
Like any living thing on Earth, they need the right conditions to survive. With the help of geologists and other scientists, we can better understand these incredible life forms and their importance in our environment.
How Long Do Rocks Live?
Rocks Lifespan | Duration to transform |
Rocks | Millions of Years |
There is no death for rock; all things evolve through transformation. As a result, they don’t have an expiration date. Rocks are always changing form, and in reality, rocks aren’t considered living beings at all.
Although rocks are not alive, they continue to exist as the Earth’s crust undergoes tectonic changes.
The word “decaying” can have two meanings – it can refer to living organisms dying off or to non-living objects being destroyed.
Rocks are non-living objects that will persist for an unimaginable amount of time unless they are physically destroyed by powerful forces such as lightning bolts, earthquakes, waves crashing against them at the beach, or molten lava spewing from a volcano.
As long as another similar rock is available for a tectonic activity to interact with, then the rock will be part of our planet until we no longer call this planet home and we’ve moved on into outer space.
Rocks are worn down or changed chemically due to exposure. Many have not survived for more than 100,000 years.
Dozens of factors influence how long a rock will live; the chemical composition of the rock, its exposure to things like water, heat, and pressure, which part of the Earth it’s on (on land or deep underwater).
We can say that most rocks break down too quickly to survive much longer than 100,000 years, and this is because what remains after one rubs away at something can now rapidly break down- without anything left over for protection.
Why Would Rocks Live For So Long?
Rocks are made up of mostly minerals that have varying degrees of resistance to degrade. Erosion occurs at a slow enough rate that it can take an estimated 10 million years for rocks representative of the Earth’s crust today to erode.
The three most important factors in altering how quickly an object degrades are water development, temperature range, and acidity (due to the presence of oxygen).
Low pH environments like those found in deserts significantly speed up the natural chemical breakdown process thanks to more readily available weathering agents like hydrogen peroxide (H2O2). Still, these same conditions freeze out biological life forms unable to function without water. Temperature also plays a role as low temperatures constrain degradation through molecular vibration.
For example, it has been observed that rocks also form in nature from sedimentary deposits. These models would say that different minerals grow together over time because of changes in pressure and temperature.
The rate at which they would grow depends on how rapidly something may be changing, such as from the ice age to glacier change from one million years ago.
Rocks live for so long because one has to do with the earth’s crust, a turbulent environment for rock, while another has its composition and geology.
Sometimes, rocks dry out from air exposure or get covered by the soil from weathering rains or a deposition covering rocky hillsides. Either way, the result is that many rocks will eventually break down into smaller particles and merge back into the earth.
Conclusion
It takes millions of years for the rock to slowly erode, and sometimes it may take even longer. After millions and billions of years, a rock may turn into sediment, but decomposing into sediment will depend on the type of rock and its environment.
Sandstone and calcite rocks may decompose quickly in comparison with other rocks. At the same time, corundum and diamond decompose very slowly. The lifespan of the rock is unpredictable as they never die but change their form.
This is why the rock cycle starts from sediment→ sedimentary rock→ metamorphic rock→ magma due to heat, pressure, cooling, melting, compaction, and cementation.