We usually think of the science of geology as being about the past: geologists often reconstruct events that happened thousands, millions, or even billions of years in the past. Sometimes geologists are called upon to project into the future as well. Examples of this include earthquake prediction and finding sites for long-term (>10,000 years) storage of radioactive waste. Geologist Steven Ian Dutch takes a look at the prospects for the next million years in “The Earth Has a Future”, published by the Geological Society of America in the online journal Geosphere. I’ll summarize the article and then give a little commentary on it.
The article is available online in two versions:
- The PDF version is easier to read.
- The HTML version has animations that are not viewable in the PDF version.
Dutch starts with processes active on the surface of the earth—erosion, uplift, volcanic activity, plate movement, changes due to human activities—as well as the more rare events such as eruptions of supervolcanoes and meteorite impacts. He calculates the rates at which these occur at various places on the earth, and makes predictions as to what the earth will be like in one thousand, ten thousand, one hundred thousand, and a million years from now. He acknowledges that there are many uncertainties in these speculations, but it is still a worthwhile exercise.
One of the most difficult things to predict, in Dutch’s mind, is the future impact of human activity. Will humans become extinct? Will technological civilization collapse? Will humans modify the surface of the earth beyond recognition?
Some things that will happen in the next 1000 years:
- 5-7 magnitude 8 earthquakes along the San Andreas Fault, with total movement of about 25 m.
- 40 eruptions of Vesuvius
- 5-10 eruptions of Fuji
- ~12 eruptions of Cascade Range volcanoes
- Perhaps smaller volcanic eruptions in areas with lower-frequency eruptive histories: cinder cones in the SW United States, Puy region of France, or Eifel region of Germany
- 200 eruptions of Mauna Loa on Hawaii, building it 5 m higher
- Probable death of Old Faithful Geyser, as its geothermal plumbing shifts over time
- Several world-wide large volcanic eruptions (on the scale of the 1815 eruption of Tambora in Indonesia, which caused “the year without summer” in the United States and Europe)
- Little change visible in mountain ranges as they simultaneously uplift and erode
- The Mississippi River and its delta will change its course. Its delta naturally changes position every 1000 years or so, and is overdue (thanks to the Army Corps of Engineers)
- Niagara Falls will have cut back 900 m upstream from its present position
- A good chance of a meteorite impact with a crater of 100 m or more
- Most steel structures (Eiffel Tower, Golden Gate Bridge) will survive only with careful maintenance
- Humans will still be using coal and natural gas, but not much petroleum
Some things that will happen in the next 10,000 years:
- 50-70 magnitude 8 earthquakes on the San Andreas Fault, with displacement of 250 m
- Kilauea, on Hawaii, will be about 100 m higher
- Several hundred eruptions of Vesuvius
- 100 eruptions of Fuji
- 100 eruptions of Cascade Range volcanoes
- 90 m uplift of the Baltic Sea and 100 m uplift of Hudson Bay as they continue to rebound after the removal of Pleistocene ice sheets. These bodies of water will, therefore, be smaller
- By natural cycles, we would be nearing the end of the present interglacial, looking to the beginning of a new ice age
- Niagara Falls will retreat upstream by 9 km
- Higher probability of a 1 km crater formed by meteor impact, with considerable destruction up to hundreds of km away
- Without considerable care, the only human structures that will still exist are large highway cuts and large monuments
- No present human cities are 10,000 years old. Will any of our present cities exist 10,000 years from now?
Some things that will happen in the next 100,000 years:
- 2.5 km slip along the San Andreas Fault. Not enough to close the Golden Gate
- Kilauea will be 1 km higher, and Loihi (an underwater volcano SE of the island of Hawaii) will be above sea level
- Some mountain ranges will have had 1 km of uplift. In most cases, this will be accompanied by close to 1 km of erosion, so the net result will be exposure of deeper rocks, not higher mountain ranges
- Earth could be in an ice age
- Niagara Falls will stop retreating as rock types are different further upstream. A new waterfall will start forming near the outlet of Lake Erie
- There could be a meteor impact with global effect
Some things that will happen in the next 1,000,000 years:
- The San Andreas Fault will have slipped 25 km, perhaps blocking the entrance to San Francisco Bay
- The highest points of the island of Hawaii will be Kilauea and Loihi. Mauna Loa and Mauna Kea will be old and eroded
- Several enormous catastrophic landslides will have occurred on Hawaii
- Many current volcanoes will have become extinct, being replaced by others
- One or more eruptions of “supervolcanoes” such as Yellowstone or Long Valley, California. (The last large eruption at Yellowstone, 640,000 years ago, had a volume of 1000 km3, as compared to 0.5 km3 for Mount St. Helens 1980)
- Some rivers will have changed their courses
- Ten or more major periods of glaciation
- Hundreds of meteor impacts
- The earth’s day will be 20 seconds longer (due to tidal effects)
- The moon will be 38 km further away
- The solar system will have traveled 750 light years in its orbit around the center of the galaxy
- The only present human structures to survive will be large and made of earth and stone: open-pit mines, large road cuts, mine waste piles, the Pyramids. (Even the Pyramids might not make it if the climate becomes more humid in that area).
25 km displacement along the San Andreas Fault at San Francisco, one million years in the future. The west side of the fault is moving north relative to the North American Plate.
Commentary
This kind of reasoning is increasingly important in the earth sciences: trying to figure out what has happened in the past and what is going on at the present in order to make predictions about what is likely to happen in the future.
Some issues that come to mind as a Christian thinks about the future of the earth:
- This paper puts our human achievements in a good perspective. All that we create is of a very temporary nature. Compared to the universe and the potential vastness of time, we are rather small. The purpose of this isn’t to magnify the creation, but to magnify the Creator. God is to the universe as the universe is to us. And that is an understatement.
- The perspective of the paper is that geologic time will roll on, and that humans may just be a temporary species on the earth. Humans, in this way of thinking, are an accident of evolution, and the future of the earth will be billions of years, whether we are present or not. History has no direction or purpose. This stands in contrast to the Biblical perspective that creation has a purpose and history will come to a culmination at the return of Christ and the restoration and remaking of creation.
- In regards to the concept of a long future history of the earth, we know that Christ is likely to return before the next thousand, ten thousand, hundred thousand, or million years pass. Christ could return at any time, but it is not incomprehensible to think that Christ could return more than a thousand years in the future instead. I have a more difficult time thinking of Christ’s return being orders of magnitude further into the future.
- God is sovereign over the events of the future. This does not rule out the type of investigation that has been done here—we can seek to understand how the earth works and then project that into the future. This is the geological principle of uniformitarianism properly applied to the future. It has its limits, but it can also be a powerful tool.
- The earth does have a future, at least as a new heavens and new earth (Revelation 21:1). Our eternity will not be spent strumming harps on clouds, but on a real, physical earth that is in many ways like the one we live on. It will have rocks and trees and bodies of water. It may be different in some ways than the present earth, but it will still be “earthy.”
- Will the new earth have volcanoes? Earthquakes? Uplift and erosion? Plate tectonics? I don’t know. We tend to think of things like volcanoes and earthquakes as “bad,” but I believe these things could fit under the phrase “it was good” from Genesis. Volcanoes, for example, can renew the surface of the earth, and provide rich soils. “Good” isn’t the same as “safe;” in fact, dangerous things have a way of showing God’s glory to us.
Grace and Peace