Geologist John Shelton’s photographs showcased

An exhibit featuring 33 aerial photographs by La Jolla geologist and educator John Shelton will be on display at the San Diego Natural History Museum from May 11 to Nov. 2.

The show, “Aerial Portraits of the American West,” offers a unique perspective of geologic formations and processes from Alaska to Baja California. The photographs were taken by Shelton over the course of several decades.

“It’s a collection of four by five (inch) negatives that John shot from the 1940s right up through the ‘70s,” said Michael Field, the exhibit designer.

Shot with a military aerial reconnaissance camera, the negatives are so large that they show tremendous detail. Many of the photos cannot be reproduced because the air clarity has been irreversibly tainted with pollution.

“I’m one of his fans,” Field said. “When I took geology in college back in the day, I remember looking at his pictures and having an ‘aha’ moment.”

A third-generation La Jollan, Shelton was home-schooled until the seventh grade when he enrolled at Francis Parker School. He graduated from La Jolla High in 1931 and went on to Pomona College.

“I didn’t discover geology until my junior year,” Shelton said. Too far along in his studies to change majors, he graduated with a dual degree in math and music.

He returned to Francis Parker but could not escape enthrallment with the earth’s history.

“It’s fascinating to speculate on where we all came from and where we’re all going,” Shelton said.

He turned to the college professor who had introduced him to geology, and upon his advice, applied to Yale. Lacking the credits necessary to qualify as a graduate student, Shelton’s first year was spent catching up.

“I feel like my whole life has been a procession of (overlapping) interests,” he said.

Shelton resumed teaching and worked for the U.S. Geological Survey. An avid pilot, he logged almost 6,000 hours over his lifetime.

Always on the lookout for a new way to reach his students, Shelton began taking photographs of different land formations to demonstrate the dynamic geologic forces at work. His collection, begun in the ‘30s and continuing through the ‘90s, spans the globe, including Scandinavia, Europe and the U.S.

One of Shelton’s favorite teaching philosophies is, “Don’t give the answers before the questions are asked.” Critical of textbooks and curriculums that teach geology through memorization, he authored “Geology Illustrated,” named one of the most important 100 books of the last 100 years by Scientific American.

Shelton, 94, calls himself a “student of the earth.” He is passionate about the world and helping others understand and appreciate the elements that have sculpted the planet as it appears today.

He sees humans and earth as having an interdependent relationship: humans cannot survive without the riches of the earth, released through processes such as weathering.

“You can’t escape geology,” he said. “Every step you take is on some kind of rock. You can see the processes of construction and destruction that take place.” Shelton worked with friend and fellow photographer Bill Evarts for two years to prepare for the exhibit at the Natural History Museum. Most of the photographs are black and white, and portray geologic phenomenon such as faults, uplifted mountains, erosion patterns, folds, lava flows and meteor impact sites.

“It’s fun to show (people) things they think they’re familiar with from a brand-new angle,” Shelton said.

Jay, one of Shelton’s five children and also a science teacher, recalled what it was like accompanying his father on flights to capture his stunning pictures: “You couldn’t go there at any old time. You had to be there when the sun came up.”

Many adventures started well before the break of day so that Shelton arrived when conditions were perfect.

Like his father, Jay Shelton is a dedicated teacher who adopted the “show, don’t tell” approach.

“You guide discovery; you don’t feed education,” Jay Shelton said. “I absolutely adore teaching and I’m continuously looking for new ways to teach. I attribute an enormous amount of this to my father.

Recognized as one of the most influential geologists in the country, Shelton’s photographs provided evidence of principles such as continental drift and plate tectonics. One of his most well known photos showcases an orange grove that straddled the San Andreas fault and was misaligned during an earthquake.

“It clearly illustrated the land we live on is … moving north,” Field said. “It provided this evidence or body of work for people to better understand the concept of the earth in motion, this elastic crust we live on.”