My experiments with volcanoes

by Thomas Augustus Jaggar

The Volcano Research Association, in cooperation with Hawaii National Park, built a trail side museum and lecture hall atop the high western bluff of Kilauea Crater. Later, when the drive was extended completely around the greater crater, the museum was on the road to Halemaumau. This museum had a plate glass front, concrete floor, skylight illumination, and an esplanade looking down on the caldera and across the vast panorama of Mauna Loa, Mauna Kea, and the Kau Desert. The building protected the lookout platform from the trade winds.

We housed in the museum a gleaming, nickel-plated seismograph from Japan, suitable photographs, and the best of our specimens for visitors to see. This combined with the magnificent views to instruct the public in volcanology as nothing else could have done. At the same time, I equipped machine shops and added a first class mechanic to the staff.

It was during this decade and after my New Zealand trip that such persons as Omori and Nakamura, in Japan, and geologists in Seattle, Berkeley, and Pasadena began to take an interest in the volcano problem as dominant in the study of earthquakes.

There were conflicting theories about the earth crust. Earlier, in Hawaii, Wood was a disciple of the tectonic or contracting theories of the earth, whereas I increasingly believed volcanism to be profound, crustal, oceanic, and ancient. It is more fundamental than the strata and mountain folds of continents.

This conflict extended to the water question in volcanology. I was inclined to believe the waters of eruption to be oxidized hydrogen, whereas such physical chemists as Day, Shepherd, and Allen believed water vapor, like carbon dioxide, to be fundamental in magma.

The whole question of the origin of oxygen—the most abundant element of the rocks, air, and water—is a matter of startling doubt in geology. Where oxides are known to exist in lava, flames of oxidation make the gaseous fires; and underground water full of oxygen plays a part in steamblast eruption. All the waters of glaciers and oceans are oxides, and prove that the volcanic oxidation of hydrogen was the most primitive of the volcanic processes. Dr. E. H. Allen found water vapor dominant in the Sulphur Bank gas at Kilauea, whereas Day and Shepherd, who opposed Brun, thought water dominant in the gases of live lava. Its great preponderance in geological theory for such eruptions as Vesuvius led Allen to review theories and publish a long paper designed to refute my notion that oxidizing hydrogen is the primary volcanic ingredient.

As to earthquakes and so-called tectonic faults, the whole of geology has its thinking so warped by continents, the dwelling place of mankind, and so diverted from the great linear trenches and the ridges of the ocean crowned with volcanoes parallel to the deeps, that I became incredulous, along with Willis and Oldham, about the textbook cause of earthquakes.

The fascination offered by fossils, by ages of shellfish and reptiles, and by mountains of folded strata like the Alps and the Himalaya makes the votaries of evolutionary science neglect the mud-covered rocks and oceanic mountain ranges of almost three-quarters of the surface of the globe. This seventy-two percent they have never seen, nor collected hard rock specimens from, nor even mapped topographically. They are not acquainted with it by exploration, and their theories about it are a blank, except that gravity pendulums indicate it to be basalt.

The so-called geosyncline, or continental basin of sediments, filled with shells and strata as is the Mediterranean, is at the heart of all the theories of continents and mountains; and geology expressly excludes the geosyncline and its strata from the probabilities of deep ocean valleys. The most interesting subjects of continental geology are simply banished from conjecture. Interest in deep-ocean geology is lacking because science has made no field effort to bore or blast into it, and so extend engineering science to the deep ocean bottoms.

Earthquakes made a theme wherein I instinctively distrusted the word “tectonic.” For generations the geological mind thought the earth losing heat, contracting internally, and wrinkling a crust in bumps, with vast overthrusts of broken strata, thus folding the Appalachians and the Andes. All sorts of accommodations to a thin crust thirty miles deep were invented; by Dana and Geikie, by Suess and Wiechert, and finally by one who should have been the foremost block faulting expert, Dutton. Hawaii convinced him that volcanoes are only skin deep and that the thin crust is so sensitive that a shift of the weight of river muds and sands is enough to push down the great valley of California, while an underflow pushes up the Sierra Nevada. This is the doctrine of “isostasy.” It agrees with the Stübel idea of shallow remnant reservoirs for the lava of volcanoes.