science · 19 May 1871 · 153 years ago
birth
Born 19 May 1871; died 19 Sep 1957 at age 86.
Canadian-American geologist who independently developed the theory of magmatic stoping, a process in which magma moves up through the Earth's crust the earth by shattering (but not melting) the overlying rock. Resulting broken blocks of denser rock sink, leaving space for the rise of the magma. This explained the structure of many igneous rock formations. Daly believed in the importance of field studies to investigate geologic processes. He based his theory of the origin of igneous rocks on an extensive study of hundreds of miles of landforms along the 49th parallel. From another project exploring the geology of the Samoan Islands, he developed theories relating glacial effects on sea level to the formation of coral atolls. His book Igneous Rocks and Their Origin (1914) was a popular instructional text for many years.
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