Peripatetic Volcanologist

Most people in thus Country became interested in volcanoes when Mount St. Helen's erupted in 1980, but Dick Stoiber '32 has had a consuming fascination with volcanoes for 20 years. Although he is known today as a volcanologist, the roots of this fascination can be found in his early interest in ore minerals and mining geology. His first scientific paper, published in Economic Geology in 1940, was about the zinc mineral sphalerite. During World War 11, his research focused on prospecting for high-quality quartz crystals for the U.S. Army Signal Corps. After the War, until the mid-fifties, his research interests returned to the geology of metallic ore deposits. Of particular interest to him were the native copper deposits of northern Michigan. His research and consulting work during this period took him to various locations in North America, Europe, and Central and South America.

In the early sixties, Stoiber became intrigued with the possible relationship between the genesis of ore deposits and the processes leading to volcanism. This led him to commence a study of the hot gases emitted from and the minerals surrounding vents in the craters of active volcanoes. Because of the large concentration of active volcanoes there, Central America became a natural laboratory in which to conduct his studies. Most of his work has been carried out in Guatemala, El Salvador, and Nicaragua, but in recent years his work has shifted to Costa Rica.

With the advent of the unifying concept of the continental drift theory known as plate tectonics in the late sixties, Stoiber directed his research, and that of his students, to the role of volcanoes on a dynamic earth. These studies have carried him to the active volcanic provinces of Central America, North America, Europe, Africa, Asia, Iceland, and the Pacific islands. He and his students have produced an important new concept about the cause of lateral offsets in linear volcanic chains that is now gaining wide acceptance. Their idea is that the shifting of rock bodies deep in the crust breaks up what should be a straight line of volcanoes on the surface. He also supervised a ten-year mapping project that sent more than 40 Dartmouth seniors and graduate students into the rugged highlands of southern Guatemala, each for a three-month period, to gather basic data about the poorly-understood older volcanic rocks of the region. This has resulted in a better understanding of the volcanism and tectonics that have occurred in the region over the last 30 million years. To date, four new maps have been published and another three await publication.

Throughout his career at Dartmouth, Stoiber has been interested in the identification of mineral species through the use of a polarizing microscope a skill that is basic to most fields in geology. With his former student S. A. Morse '52, he published Microscopic Identification of Crystals, in 1972, a book that has become a standard reference on the subject throughout the English-speaking world. In 1974, a Russian edition of the text was published in Moscow.

In the mid-seventies Stoiber pioneered the use of the correlation spectrometer on erupting volcanoes. With this instrument which measures the amount of sulfur dioxide in the atmosphere, he and his colleagues have observed numerous eruptions and produced several landmark papers on the subject. In one instance, potential health problems were found in a small Nicaraguan village situated directly from a volcano that was emitting large amounts of sulfur dioxide. Because of the nature of his studies, Stoiber has continued to travel worldwide. He and two of his grad students were on hand to measure the gas emissions from the eruption of Mount St. Helen's. Other large eruptions have also interested him. In the summer of 1983, he and one of his graduate students presented a paper on volcanic gas from the eruption of Krakatau at a meeting honoring the centennial of the event in Jakarta, Indonesia.

But whatever the volcano, whenever Stoiber talks about his specialty, observers can't help becoming captivated by his effervescent personality and his particular interests in the field of geology.