Earth Science Week

A week to celebrate learning about Earth Science

Chemistry in Mining

During Earth Science WeekTM, we went to a lecture by Dr. Innocent Pumure from UCM called “Sonochemical Extraction of Arsenic and Selenium from Pulverized Rocks Associated with Mountaintop Removal Valley Fill (MTR/VF) Method of Coal Mining”.

You may be wondering, what is Mountaintop Removal Valley Fill Mining? First, the excavation company blows up (or strips) the top part of the mountain to remove vegetation and expose the coal seams. The coal seams are then mined through the open cast/strip method, and the extra rock and soil is dumped in nearby valleys called valley fills. It is cheaper and easier to do than regular mining, where they dig a vertical shaft down and do everything through the tunnel, but it blasts the mountain apart and looks ugly. Since 30% of electricity in the USA comes from coal, valley fill mining is still pretty popular.

In 2002, the EPA found too much selenium downstream of a certain mine in West Virginia (we’re not going to say which one). It was over 5 ng/mL, which was the limit back then.[*] 7 years later, there was still an active mine there and the water still had too much selenium. Even worse, the surrounding sediment had 10.7 mg/kg selenium. This could cause problems for the environment later. Due to bioaccumulation, you could say once it’s in there, it’s really in there.

So now we get to the topic of Dr. Pumure’s talk, in which he and his colleagues discovered a way to quickly find out how much selenium and arsenic were in the ground around this mine in West Virginia. When you do a chemical analysis, you usually have to break down the samples in order to measure what is in them. One method to do this would be to take some core samples and do an acid extraction, but that takes a long time and uses a lot of reagents. Sonochemical extraction uses ultrasound energy to accelerate the leaching process that would naturally happen as rocks become weathered. Since it is ultrasound, it does not directly touch the sample, is minimally invasive, and does not need any reagents except water.

Next, he explained the methodology, which means a description of exactly how they did it in the lab: the size of the extraction cells, how much water and power were used (200W/cm3), how long the samples were sonicated, and all the other pertinent information for chemists. Pumure actually spent quite a lot of time finding out the optimal sonicating time to get the best extraction. It turned out the best times for his sample sizes were 20 minutes for Se and 25 minutes for As. That’s really fast![**] Then, he did a comparison to a chemical sequential extraction to make sure that the sonochemical extraction method was getting everything. To summarize, yes it was. Finally, he did a principal component analysis of core samples from different places all over the mountain using this same technique. They found some really interesting trends and correlations, for example, it appears that there is more arsenic in illite clay than other types of clay.

This research has many useful applications. If you were running a mine, you could take samples more frequently to see if your mine is polluting the surrounding environment, and then you could do something about it before the EPA finds out. The method could probably be used for other analytes, too. For other research needs, you could now quickly analyze large batches of mineral samples to get lots of data that would otherwise be too expensive or time consuming to obtain.

[*]The EPA has since lowered the limit and now it is 3.1 ng/mL.
[**]For comparison, some of my colleagues do chemical extractions that take 2 days.
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Earth Science Week 2017

earth science week logo

This week (October 8-14, 2017) is Earth Science Week and the theme is “Earth and Human Activity.”

According to earthsciweek.org

“This year’s event, the 20th annual Earth Science Week celebration, promotes awareness of what geoscience tells us about human interaction with the planet’s natural systems and processes.

“Earth Science Week 2017 learning resources and activities are engaging young people and others in exploring the relationship between human activity and the geosphere (earth), hydrosphere (water), atmosphere (air), and biosphere (life). This year’s theme promotes public understanding and stewardship the planet, especially in terms of the ways people affect and are affected by these Earth systems.”

Be on the lookout for fun activities in schools and in the community to promote awareness of earth science this week, and National Fossil Day this Wednesday.

National Fossil Day

National Fossil Day saber-toothed cat long-horned bison condor

The 2016 National Fossil Day logo

October 12 was National Fossil Day. This has been going on since 2010 as part of Earth Science Week, but I forgot to post anything about it. According to their website, “National Fossil Day is a celebration organized by the National Park Service to promote public awareness and stewardship of fossils, as well as to foster a greater appreciation of their scientific and educational values. Fossils discovered on the nation’s public lands preserve ancient life from all major eras of Earth’s history, and from every major group of animal or plant. In the national parks, for example, fossils range from primitive algae found high in the mountains of Glacier National Park, Montana, to the remains of ice-age animals found in caves at Grand Canyon National Park, Arizona. Public lands provide visitors with opportunities to interpret a fossil’s ecological context by observing fossils in the same place those animals and plants lived millions of years ago.”

This year, the theme of National Fossil Day is the Pleistocene era, so the logo has a saber-toothed cat, a long-horned bison, and a condor. In the background is Tule Springs Fossil Beds National Monument. To read more about these extinct animals, their website has an explanation here: http://nature.nps.gov/geology/nationalfossilday/nfd_2016_artwork_fossils.cfm

There was also a kids’ art contest, and here are the winners: http://nature.nps.gov/geology/nationalfossilday/art_contest_2016_results.cfm

Earth Science Week 2015

Earth Science Week is October 11-17, 2015

Earth Science Week logoEvery year, the Missouri Department of Natural Resources (MO DNR) has an Earth Science Week full of fun activities for kids and adults. From their website: Earth Science Week aims to help the public gain a better understanding and appreciation for the Earth Sciences and to encourage stewardship of the Earth. This year’s activities will be held Oct. 11-17 and will celebrate the theme “Visualizing Earth’s Systems.” This year’s theme will engage young people and others in discovering the Earth sciences, remind people that Earth science is all around us, encourage Earth stewardship through understanding, and to motivate geoscientists to share their knowledge and enthusiasm about the Earth.

Go ahead – be a citizen scientist!

Enter the photography, visual arts and essay contests! All eligible submissions must be submitted to the American Geosciences Institute and received electronically by 4 p.m. CST, Friday, Oct. 16, 2015.

Participate in events during Earth Science Week. Plan a visit to the Missouri Geological Survey during Earth Science Week. The Missouri Geological Survey will be open during Earth Science Week from 8 a.m. to 5 p.m., Tuesday-Friday, Oct. 12-16.

Read our Governor’s Proclamation!

  • Sunday, Oct. 11 is International EarthCache Day – Explore the world using your GPS.
  • Monday, Oct. 12 Earth Science Literacy Day Learn the fundamentals of geosciences with Earth Science: Big Idea, a video series developed to explain why Earth science literacy is important.
  • Tuesday, October 13 is No Child Left Inside Day  NCLI Day encourages students to go outside and research Earth science in the field like a professional geoscientist.
  • Wednesday, Oct. 14 is National Fossil Day – Visitors to the Ed Clark Museum of Missouri Geology, in Rolla, will receive a Crinoid fossil. Also, be sure to check out the fossils in the limestone of the Missouri State Capitol.
  • Thursday, Oct. 15 is The Great Central U.S. ShakeOut – Register and join millions in the “Drop, Cover, and Hold On” earthquake drill Oct. 15 at 10:15 a.m.
  • Thursday, Oct. 15 is Geoscience for Everyone Day Do your part to help young people from underrepresented communities explore exciting careers in the geosciences.
  • Friday, Oct. 16 is Geologic Map Day – Special mapping exhibits were on display at the Ed Clark Museum of Missouri Geology during Geologic Map Day to promote awareness of the study, uses and importance of geologic mapping for education, science, business, and public policy concerns.
  • Saturday and Sunday, Oct. 17 and 18 the Ozark Mountain Gem and Mineral Society’s Gem and Jewelry Show will be held in the at the Expo Center in Springfield, Mo. – Geologists with the Missouri Geological Survey will host an educational booth Saturday, Oct. 17.
  • Saturday, Oct. 17 is International Archaeology Day – Hosted by the Archaeological Institute of America, this special event is a celebration of archaeology and the thrill of discovery.