Edward Ching-Te Chao, 88, trailblazer in geology fields
WASHINGTON - Edward Ching-Te Chao, a geologist whose identification of two dense forms of minerals in nature paved the way for scientists to understand the structure of the Earth's mantle, died of congestive heart failure Feb. 3 at his home in Fairfax County, Va. He was 88.
Dr. Chao, who worked for the US Geological Survey for 45 years, studied a variety of substances, including minerals of the Meteor Crater in Arizona, rocks in the Ries Crater in southwestern Germany, ore deposits in Inner Mongolia, and moon rocks that astronauts recovered in the late 1960s.
He was the first person to recognize two high-pressure forms of silica in nature: coesite and stishovite. For this work, Dr. Chao was awarded the Wetherill Medal of the Franklin Institute in 1965.
The identification and description of both minerals was "a really huge discovery for this field of high-pressure minerology and had very important implications for geophysics," said Russell Hemley, director of the Geophysical Laboratory at the Carnegie Institution of Washington.
The discovery of those minerals, found beneath the surface of the Earth but never before seen on its surface, helped scientists understand the role that meteors play in the planet's formation.
"He founded the field of impact metamorphism," said Ahmed El Goresy, professor of cosmochemistry at the University of Bayreuth in Germany. "This is his own child. It has become a very big business in science."
More of a practical scientist than a theorist, Dr. Chao was known for his field work and meticulous collection of evidence and documentation.
"I've been involved in controversial studies during my whole career," Dr. Chao told The Reston Times in 1992 after an asteroid was named for him. "People don't believe, but you do your hard work. It takes time to gradually convince them. You always have to find new, better evidence."
Dr. Chao was born in Suzhou, China, and moved to the United States in 1945 to teach Chinese to US troops. When World War II ended, he graduated from the University of Chicago and received a doctoral degree in geology.
He moved to Alexandria, Va., to work for the Geological Survey, where he stayed until retiring in 1994. He began in military geology, then transferred to the survey's branch of geochemistry and petrology, which deals with the classification, location, composition, and origin of rocks.
From 1960 to 1977, Dr. Chao worked on meteor and lunar studies. Detailed to NASA to work on designing the lunar sampling program, he was a member of the preliminary examination teams and a principal investigator for the Apollo research programs. For the Apollo 12 mission, he was sequestered with the astronauts to analyze the moon rocks they brought back.
His research in the areas of terrestrial and lunar impacts was rewarded with the Barringer Medal by the Meteoritical Society in 1992, whose citation called him the "quintessential founder of a new area of research in metamorphic petrology: impact metamorphism of natural rocks."
In addition to the asteroid, the mineral chaoite, which was discovered in the Reis Crater, was named for him.
Dr. Chao led one of the first scientific exchanges between the United States and Chinese governments in 1972 to promote the reestablishment of diplomatic relations.
After retiring, Dr. Chao pursued his many other interests, including mind and consciousness research as related to Buddhist teachings, Chinese calligraphy, and music.
His marriage to Vera Chao ended in divorce.
Survivors include his wife of seven years, Yong-Sil of Fairfax County; three children by his first marriage, Katherine Evans of Worcester, Mass., Evelina Chao of St. Paul, and Daniel of Oakland, Calif.; three stepchildren, Shey Wakely of Falls Church, Va., Unyong Waide of Arlington County, Va., and Hyong-Bum Kim of Palo Alto, Calif.; two brothers; 13 grandchildren; and a great-granddaughter.
