74 | Great Geologists
Chamberlin was, literally, “born on a moraine” in south-
eastern Illinois in 1843. Soon after, his father, a Methodist
circuit minister and farmer, moved the family near to Beloit in
southern Wisconsin. Chamberlin excelled as a scholar at the
local college and initially became a teacher, and later principal,
of a local high school. By 1873, he was back at Beloit College
as professor of geology, zoology and botany.
1873 also marked the beginning of his serious research
endeavours, beginning a comprehensive geological survey
of Wisconsin and in particular its glacial geology. By 1876,
he was Chief Geologist of the Wisconsin Geological Survey
and within six years had completed a large four-volume
treatise of the geology of the state. This brought him national
attention and he was appointed Head of the glacial division
of the National Survey in 1881. His research led him to be the
first to demonstrate that there had been multiple Pleistocene
glaciations in North America. Using features such as
moraines, drumlins and eskers, he was able to map the limits
of the last two glacial advances.
His full-time activities with the U.S. Geological Survey proved
to be short-lived. His organisational and administrative skills
led him to being invited to be President of the University of
Wisconsin at Madison. This would prove to be a break from
his research, but he undertook the role from 1887 to 1892,
greatly reforming the university for the better.
In 1892, the opportunity arose for him to return to geology
full time with an offer to organise a department of geology at
the new University of Chicago. He was to remain there until
his retirement in 1918, creating and leading a distinguished
faculty and research programme. From there he launched
Journal of Geology, partly as a vehicle for the prolific
outpouring of his scientific ideas.
His range of activities was immense, although a common
theme was the origin of the Earth and how this influenced
Earth’s history, structure and processes. At the heart
of this was his planetisimal theory for the origin of the
planets, developed with the Chicago-based astronomer
Forest Moulton. In this theory, immensely hot matter
expelled from the sun and dragged out by the gravitational
attraction of a passing star accreted to form cold objects
(planetisimals). They acquired an orbital motion around
the sun and periodically collided to accrete even further,
eventually to form the planets that exist today. Once formed,
the Earth was subjected to continuing, but episodic, radial
gravitational contraction. For Chamberlin, these contractional
events caused mountain building due to differential vertical
Chamberlin’s 1894 map of Pleistocene ice extent in North America
based on the mapping of moraines and other glacial landforms.
movements of radial Earth segments. Oceanic subsidence
caused less dense continental blocks to move upwards in
accordance with isostatic principles. Chamberlin’s Earth was
solid to its core, so there was no fluid interior on which blocks
of crust could founder.
Episodic tectonic events provided a control on global sea-
level and continental erosion, and in turn explained the natural
events that led to the biostratigraphically-based subdivisions
of geologic time (regression leading to extinction;
transgression leading to new fossil species occupying newly
created niches). There are echoes of the catastrophism of