Friday, December 18, 2020
Dr. James Knapp’s research may change the current understanding of how the world works
Earth has evolved over time.
Dr. James Knapp, an Oklahoma State University professor and Boone Pickens Distinguished Chair of Geoscience, and his research team are studying that evolution — specifically how continents break apart, called rifting.
“It’s a mechanism where, over geologic time, the large plates that make up the outer portion of the earth, move around and interact with each other and crash together and make big mountain belts and form volcanic chains,” he said. One of the key processes of plate tectonics is this process of continents breaking apart periodically and forming new plates and new ocean basins.
“If you wind the geologic clock backwards 250 million years, all of the continents were assembled in a supercontinent of Pangea, and since that time we had the rifting of the continent to form the collection of continents that we have today,” Knapp said. “So, this study was focused on how that process is recorded in the eastern margin of North America.”
Knapp’s study was published in Nature Communications, a subsidiary of the Nature Journal. The article, titled “Limited and localized magmatism in the Central Atlantic Magmatic Province,” argues for rethinking how the Earth works. Continents breaking apart changes a lot of the Earth’s structure, even down into the mantle, Knapp said.
This melting of the internal material produces a lot of magma, so rifts have historically been perceived to include a lot of volcanic activity, he added. Knapp and his team contend that may not be true.
“This paper comes to the conclusion that the size of the magmatic province was very limited and localized within these rift-related structures,” he said. “It appears to be orders of magnitude less than what previous researchers have proposed for the Central Atlantic Magmatic Province.”
These processes take place over millions of years, Knapp said. In the East African Rift, the next area Knapp and his team plan to study, the process has taken more than 20 million years.
“This research has the potential to rewrite our understanding of what the relationship is between breaking of a continent and that whole magmatic province. Hopefully it will guide new investigations into what is seemingly a fundamental aspect of how the Earth works.”
“The idea of going over to study what’s going on in East Africa is so interesting,” he said. “That is the place that most closely represents the process that has gone on, essentially, throughout geologic history, as long as there’s been plate tectonics operating.”
The Afar portion of the East African Rift is in Ethiopia, where OSU has a long-standing relationship.
In 1949, during his inaugural address, U.S. President Harry Truman outlined a plan to provide technical assistance for developing countries in the wake of World War II. OSU President Henry G. Bennett was appointed by President Truman as an assistant secretary of state to lead the Point Four program, which later became USAID.
One of the things this program accomplished was creating a new university in Ethiopia called Haramaya.
“[Current OSU] President Hargis actually went [to Haramaya] last summer and gave the commencement speech in honor of the long relationship between OSU and Ethiopia,” Knapp said. “There’s a really tremendous connection there.” On top of that, members of OSU faculty have ample experience working in Africa.
“If you look at the East African rift as a whole, it’s essentially a big chunk of Africa that’s in the process of ripping off the rest of Africa and forming a new ocean basin,” Knapp said.
There are a lot of aspects of the whole process that scientists haven’t figured out yet, Knapp added.
“There are ways that we can’t necessarily anticipate that the fundamental research is going to have some direct impact on somebody in, let’s say, Oklahoma,” Knapp said. “But the tie into both climate change and evolution of life on Earth is, I think, pretty significant.” He added that improved understanding of how these solid Earth processes are linked to the atmosphere and the hydrosphere and the other parts of the Earth that humans interact with, the better our response to these issues will be.
“That is why it’s so important to go back and look in detail at the data,” he said. “It can tell us about how climate has evolved in the past.”
Understanding and identifying the driving forces behind those climatic changes is the key to trying to figure out what is going on with climate variations in the modern world, Knapp said.
“This research has the potential to rewrite our understanding of what the relationship is between breaking of a continent and that whole magmatic province,” he said. “Hopefully it will guide new investigations into what is seemingly a fundamental aspect of how the Earth works.”