Tag Archives: deep time

How Dust can help control Climate Change

Research by a University of Oklahoma scientist could lead to novel way to fight climate change. It has to do with dust.

Dr. Gerilyn Soreghan, courtesy University of Oklahoma

Dr. Gerilyn Soreghan, courtesy University of Oklahoma

Dr. Gerilyn Soreghan and a team of researchers from the University of California Riverside, Florida State University, University of Leeds, Hampton University, and Cornell University have been looking at some really old, iron-rich dust deposits. Like 300-million year old dust from the late Paleozoic period.

(I’ve talked with Dr. Soreghan before, click here and here to learn more about her.)

Dr. Soreghan says Earth’s atmosphere was as dusty as it has ever been 300 million years ago. She says it’s important to study those dust deposits because of the impact they had back then on Earth’s climate.

Here’s why: dust carries iron- iron is a fertilizer for plants- plants use photosynthesis-photosynthesis removes carbon from the atmosphere and replaces it with oxygen.

Dr. Soreghan says deep-time dust contained a lot of iron which means it “…should have even larger consequences for burial of carbon.” As for the modern day, there’s talk of iron fertilization as a geoengineering scheme to control the amount of carbon in the atmosphere.

Dr. Soreghan says her study on deep-time events shines a light on how those types of geoengineering endeavors may work in the present day but, she says, more research is needed.

You can read more on the study in this brief write-up by Dr. Soreghan or here where the Geological Society of America has published an article. The National Science Foundation and American Chemical Society funded the research.

 

 

A Golden Spike in Oklahoma Marks the Spot

A Golden Spike in Oklahoma marks a geologic boundary that has the attention of scientists across the world. The picture below shows what’s called the Katian Golden Spike. It’s been placed near Atoka (about 45 miles southeast southwest of McAlester).

The Katian Golden Spike near Atoka. Courtesy: Dry Dredgers

The Katian Golden Spike near Atoka. Courtesy: Dry Dredgers

So what’s up with a big gold spike being hammered into the rocks? Well, long story short- it marks the beginning of a span of geologic time. This particular spike represents the start of the Upper Ordovician Katian Stage. The Ordovician Period is a span of time that lasted from about 485-million years ago to 443-million years ago. The Katian Stage was the second to last stage of the Ordovician. It lasted about 8-million years.

The spike marks a Global Boundary Stratotype Section and Point or GSSP. The location for a spike is determined by the first appearance of a particular species in the geologic record. In the case of the Katian Golden Spike, it marks the first place where Diplacanthograptus caudatus was found…a small aquatic animal that just floated around.

Kyle Hartshorn is with Dry Dredgers, “the oldest continuously-operating fossil club in North America”. He was also part of a group that recently toured Oklahoma’s geology and placed the spike in Atoka. He says these kinds of fossils look like little zippers or feathers, “These floating colonial animals were widely distributed by ocean currents, making them excellent tools for stratigraphic correlation.  Other wide-ranging planktonic fossils are also found at the site, including conodonts (teeth-like structures from tiny lamprey-like primitive fish) and chitinozoans (little sac-shaped fossils of unknown origin).”

The placement of a Golden Spike is mostly ceremonial, according to Hartshorn, but it does help scientists who do research there in the future. There are Golden Spikes placed around the world but only six , including the Katian Spike in Atoka, are in the United States.