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Ellis Abel Learns.

In my own words · Gregory County, SD

Why I love rocks

Cylindrical rock cores laid out in trays at the USGS Core Research Center, showing bands of different rock layers. Real USGS photograph used on the Ellis Abel Learns "Why I Love Rocks" page — read by families in Gregory County, SD.
Cylindrical rock cores laid out in trays at the USGS Core Research Center, showing bands of different rock layers. U.S. Geological Survey · Public domain
  • Every rock came from somewhere.
  • I can tell them apart by how they scratch.
  • Some of these are older than anything alive.

You can love rocks in Gregory County.

What it really is

Rocks record how they formed — from heat, from pressure, or from settling.

Three things to try today

  1. Collect five different rocks.
  2. Try to scratch each one with a coin.
  3. Sort them from softest to hardest.
Geologist Jonathan Caine swings a rock hammer against a fault outcrop in Deadman Gulch, Colorado, to break off a sample. Real USGS photograph used on the Ellis Abel Learns "Why I Love Rocks" page — read by families in Gregory County, SD.
Geologist Jonathan Caine swings a rock hammer against a fault outcrop in Deadman Gulch, Colorado, to break off a sample. Scott Minor, USGS · Public domain

For the grown-up reading this

Gregory County is one of 66 counties in South Dakota. Somewhere in that number is a kid who lights up about rocks and has never met another one.

The scratch test is real mineralogy. Hardness is a diagnostic property.

If the kid who loves this is a girl

Read what one popular teacher said to one little girl who took out the classroom trash without being asked — and what that girl did with the rest of her life.

Girls are great at math — Gregory County, SD →

Love something else too

Three orange lava fountains jet more than 100 feet above the fissure 8 cone during the 2018 Kilauea eruption. Real USGS photograph used on the Ellis Abel Learns "Why I Love Volcanoes" page — read by families in Gregory County, SD.Why I love volcanoesA jagged crack running across desert ground with a yellow tape measure stretched over it, marking surface rupture from the 2019 Searles Valley earthquake. Real USGS photograph used on the Ellis Abel Learns "Why I Love Earthquakes" page — read by families in Gregory County, SD.Why I love earthquakesHundreds of dinosaur bones still embedded in the tilted rock wall inside the Dinosaur Quarry building at Dinosaur National Monument. Real USGS photograph used on the Ellis Abel Learns "Why I Love Fossils" page — read by families in Gregory County, SD.Why I love fossilsThe historic quarry building at Dinosaur National Monument, built over steeply tilted Jurassic rock layers that hold a dinosaur bone bed. Real USGS photograph used on the Ellis Abel Learns "Why I Love Dinosaurs" page — read by families in Gregory County, SD.Why I love dinosaursHurricane Juliette photographed from the Terra satellite as a huge white spiral of cloud with a clear eye at its centre. Real NASA photograph used on the Ellis Abel Learns "Why I Love Weather" page — read by families in Gregory County, SD.Why I love weatherThe branching channels of the Godavari River delta meeting the Bay of Bengal, photographed by the crew of space shuttle Endeavour. Real NASA photograph used on the Ellis Abel Learns "Why I Love Rivers" page — read by families in Gregory County, SD.Why I love riversThe dark ragged skyline of a Douglas fir forest at Point Reyes, California, silhouetted against a pale grey sky. Real USGS photograph used on the Ellis Abel Learns "Why I Love Forests" page — read by families in Gregory County, SD.Why I love forestsA honeybee queen marked with a yellow dot on her back, surrounded by worker bees on the honeycomb. Real USGS photograph used on the Ellis Abel Learns "Why I Love Bees" page — read by families in Gregory County, SD.Why I love bees

Near Gregory County

Why I love rocks, everywhere in the US · All things to love · STEM jobs you could do · Summer camps in Gregory County