Sea Floor Explorer H. William Menard, 65, Dies

H. William Menard, a scientific pioneer who earned a worldwide reputation for determining that the Earth’s ocean floors were dynamic areas of churning geologic activity, died Sunday after a brief illness at age 65.

Menard was a longtime professor of geology at the Scripps Institution of Oceanography at the University of California, San Diego, and a director of the U.S. Geological Survey from 1978 to 1981, where he supervised the nation’s scientific response to the Mt. St. Helens eruption in 1980. Last month he received the highest honor of the American Geophysical Union, the largest international society for earth scientists.

Menard led or participated in 25 deep-sea expeditions in the Pacific after World War II. The expeditions changed the world’s conception of the deep-sea floor as a featureless plain that had remained almost unchanged for billions of years.

Undersea Mountains

On the first expedition, in 1950, Menard and his colleagues from Scripps and the U.S. Navy Electronics Laboratory in San Diego discovered the Mid-Pacific Mountains, a 12,000-foot-high range that extends for 2,000 miles from Hawaii to Wake Island. The same trip also found a giant undersea cliff that was named the Mendocino Escarpment.

On later expeditions, Menard discovered that a series of long fault zones exist parallel to the Mendocino Escarpment at intervals of several hundred miles throughout the northeast Pacific. Similar zones, now commonly known as transform faults, exist along the entire length of the mid-ocean ridges that occur throughout the Pacific, Atlantic and Indian oceans.

Menard’s discoveries have served as the foundations for theories of sea-floor spreading and plate tectonics to explain the structure and history of the Earth. Because of Menard’s work, science now understands that ocean depths everywhere have a complex topography no older than 200 million years.

Raised in Los Angeles

Menard was born in Fresno and grew up in Los Angeles.

He received a Ph.D. in geology from Harvard University in 1949 and joined the Naval Electronics Laboratory (now the Naval Oceans Systems Center) in 1950 before being appointed a Scripps associate professor in 1955.

Menard is survived by his wife, Gifford, three children--Andrew of New York City, Elizabeth of Encinitas and Dorothy Crist of Silver Spring, Md.--and three grandchildren. Memorial services are being planned.