San Tan Valley resident Scott McFadden served in the Marine Corps for six years; deployment in the Philippines just after Mt. Pinatubo’s volcanic eruption cemented a lifelong fascination with Earth sciences. He earned degrees in both geology and business from Iowa State University – and moved to Arizona in 2011 to work as a geologist for Resolution Copper. He’s had his share of excitement; among ways he’s energized now is sharing his passion for rocks and tectonics as a geology tour guide at Boyce Thompson Arboretum, where his next guided tour will be June 25 at 8 a.m.
“The Arboretum is a great place to walk and talk geology; when I started working in Superior the first thing I noticed was the amazing strata exposed right along the highway as you approach town. Picketpost Mountain looms 2,000 feet above; it’s easy to see and begs the question why it’s so massive compared to surrounding hills. Arboretum trails provide easy access to readily-visible rock structures that draw the eye and paint a picture of what happened here tens of millions of years ago. On my tour we stand amidst the rocks of Queen Creek where the presence of a basin allows me to discuss and show rocks that date to a billion years back — kind of mind blowing, isn’t it?”
He continued, ”We walk the creek bed, picking-up gangue minerals from old mine workings in the area; one of my favorite types of rock at BTA is limestone, which is sort of an ‘all purpose’ rock, which can be altered into marble, skarn – even crushed and used in makeup, food additives and construction. Limestone also commonly retains fossils; on my last tour at BTA a little eight-year-old girl actually picked up a rock with some crinoid fossils in it!
“It’s fun to show kids the ignimbrites; to keep it simple, that’s volcanic tuff with holes in it. These ‘vugs’ are often filled with calcite or chalcedony, easily visible, and kids like it,” he added.
Geology can be intimidating, but McFadden has four children of his own – one tour with a fellow geologist kept a group of over 100 (mostly kids on a student trip) enthralled learning rocks, plate tectonics and geology.
“We provided samples of rocks from mines both local and international, which was a fantastic way to get the kids excited about our discussion. We answered questions and identified rocks for the children as new samples were ‘discovered’ during the walk,” he said.
“As a kid I was always fascinated with earth sciences: weather, chemistry, geology. What I didn’t know then was the large variety of jobs a geologist can do – something I learned after I went back to college after my son was born. I was going to be a teacher in earth science but after I took my first upper class geology course I knew I had found my calling. Geology as a science and way of life is mind blowing. I love metals: the way they behave, the way earth processes create metal bearing deposits and how/where they get deposited fascinate me but to understand that you need to know about tectonics and high/low temperature chemistry and physics. The short version is to be a geologist you have to know a little bit about a lot of different scientific disciplines. That appeals to me as I am a fairly curious person.”
Innate curiosity spurs McFadden to poll his tour groups, asking what brought them out. “Parents of young children tell me they want to expose their kids to the ‘awesomeness’ of geology and frequently to learn more themselves about this amazing area. Older visitors are frequently return visitor to the BTA because they love the peace and quiet that the BTA provides – while enriching their knowledge of the area. I make it a point to gauge why and what each group wants to discover with me, and try to cater my talk and walk to what they want.
“I have four kids and married to a wonderful woman who has no idea why I love rocks so much… but she tolerates it well! I have come to love the huge variety of climates and geology the American Southwest offers, and specifically love Arizona. My kids are all attending the ASU prep academy so I gotta give a shout out to Sparky for how great AZ has been to me and my family!”
McFadden invites all who are interested in rocks to meet him in the Arboretum visitor center breezeway June 25 for the 8:00am walk. He’s prepared to answer your most ‘Tuff’ questions — and assures your kids will have a ‘Gneiss’ time. Weekend nature walks at BTA are included with $10 daily admission ($5 for kids age 5-12); confirm event dates and times at cals.arizona.edu/bta