What Is Geologic Time?
(Dec. 20, 2007) Geologic time was involved in my previous articles on earthquakes, marine terraces, photosynthesis and changing climates. I contend that grasping the immensity of geologic time is a prerequisite to a real understanding of our planet and its life. Twenty thousand years ago, Canada was buried under three kilometers of ice and sea level was 140 meters lower. Two hundred million years ago, Gondwanaland was still intact, there was no Atlantic Ocean, and the Jurassic was young. Two billion years ago, amoebas were our most advanced animals as oxygen began to accumulate in the atmosphere.
To assist your mind in grasping such enormous expanses of time, consider the rate at which a finger nail grows, 40 mm per year. After one million years it would be 40 km long (Rio Dell to Arcata). After one billion years it would encircle the globe, 40,000 km. Our Earth is 4.6 billion years old, a third the age of the Universe. Can you see your finger nail growing?
If you now realize that geologic time is too vast to truly comprehend, then you are primed to understand the evolution of our planet and its life.
Enjoy your holidays, and I hope the year 4,600,002,008 is kind to you.
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Today
Lanphere Dunes Restoration
STAFF PICK / outdoors / 9:30 a.m.-12:30 p.m. Meet at Pacific Union School. Help remove non-native invasives at the Lanphere Dunes Unit of the Humboldt Bay National Wildlife Refuge. Tools and gloves provided, wear work clothes and bring water. Carpool to the protected site. 444-1397.
44th Annual Kinetic Grand Championship Race
STAFF PICK / events, art, outdoors, sports, for kids, free / 9 a.m.-6 p.m. A 3-day, 42-mile kinetic sculpture race over land, sand, mud and water! LeMans start at the Noon Whistle on the Arcata Plaza. Follow the race through Manila, Eureka and into Ferndale on Memorial Day for the Glorious Finish. kineticgrandchampionship.com. 889-3024.
Open Gardens
outdoors / 10 a.m.-2 p.m. Humboldt Botanical Gardens, College of the Redwoods, Eureka. Roam the 44-acre fully fenced property. $5. www.hbgf.org. 442-5139.
Organic Gardening Seminar
garden / 11 a.m.-1 p.m. Shafer's Ace Hardware and Garden Center, 2760 E St., Eureka. Free lecture by Duncan McNeill on how to create a healthy environment and healthy soils for your plant’s roots. E-mail shafers@sbcglobal.net. 442-5734.
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