February 2021 Issue Table of Contents
Looking down on the Earth from space, the Alps appear to be a small, and possibly unimportant, adornment to the tremendous girdle of “Alpide” orogens that stretch the full width of the southern margin of the Eurasian continent. But seen up close, and with historical perspective, the Alps punch far above their weight. From the deepest prehistory of our hominid ancestors to the modern age, the Alps have been a formidable barrier to trade, communication, migration, and conquest across the small, but storied, “peninsula” of Europe—a fact brought home for me when I recently toured a museum in Bolzano (Italy) dedicated to the life and remains of “Ötzi”, a man who met his end five thousand years ago in the high peaks and ice fields of the Ötztal Alps.
Given the thousands of years that humans have traversed the wonders of the Alpine landscape, it feels fitting that many of the first modern-sounding scientific murmurings about Earth materials and history came from 17th century thinkers, such as René Descartes, Agostino Scilla, Gottfried Wilhelm Leibniz and Nicolas Steno, who lived near, travelled through, or who simply explored the Alps. And that first flowering of geology as its own discipline, in the 18th century, was largely driven by scientists at Alps-accessible French and Swiss institutions. Key figures such as Jean-André Deluc and Horace Bénédict de Saussure were dedicated mountaineers who helped shape both the human exploration of Alpine landscapes and the emerging field of the geosciences through a combination of the locals’ love for their landscape, athletic daring, and the then-new spirit of scientific inquiry. Louis Agassiz was arguably the greatest of these figures; though he spent much of his career in the United States, he was born in western Switzerland and launched his professorial career at the University of Neuchâtel (Switzerland). During the decade that he spent living and working in Switzerland, the Alps provided the springboard for two of his greatest scientific contributions: the systematic study of fossil fish from the Mesozoic limestones that were laid down in the Tethys Ocean and were preserved in the nappes of the Helvetic Alps; and the revolutionary theory, inspired by his studies of the moraines of Alpine glaciers, that the Earth had previously been subject to a widespread, and long-lasting, ice age.
Otto Ampferer (1875–1947)—a figure central to the scientific controversies at the heart of this issue of Elements—was also an important contributor to this tradition (Fig. 1). Born and raised in the Tyrol (the Alpine region at the borders of Italy, Austria, and Switzerland), Ampferer spent the entirety of his career working in the Alps, most of that time as a member of the Austrian geological survey. He was a paragon of field mapping and mountaineering, exploring the challenging Alpine landscape in a way that reached into every nook and cranny and every element of its geology. Ampferer was an early exponent of the nappe theory for the development of large-scale structures in mountain belts; even more importantly, he was the originator of a theory of sub-crustal currents in the interior of the solid earth—something that, to the modern ear, sounds suspiciously like mantle convection (Fig. 2). Ampferer imagined that these interior flows drive deformation by dragging the crust into regions of convergence and divergence, in places leading to a form of subduction and associated orogeny. Ampferer’s idea of subduction differed from what is usually meant by that term today, and might be minimized as just one of several loosely similar ideas that preceded the plate tectonic revolution. But in this issue, we see his thoughts, first developed in reaction to simply walking and observing the Alpine landscape, reflected, tested, and adapted using the most modern geophysical, petrological, and geochemical data. Geology can be seen as a scientific response to the human urge to connect with the beauties and mysteries of the landscapes in which we live. Nowhere do I see this idea more strongly than in the story of Tyrol native Otto Ampferer and the Alpine peaks in which he was able to see some hint of the Earths’ dynamic inner life.
Ampferer O (1941) Gedanken uber das Bewegungsbild des Atlantischen Raumes. Sitzungsberichte der Akademie der Wissenschaften Wien 150: 19-35