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Joseph Paxson Iddings
Problems (in Recollections of a petrologist, Joseph Paxson Iddings and Davis A. Young (editor))
Special Paper - Geological Society of America (June 2015) 512: 185-194


Extract from beginning of chapter:FLASHBACKWhile at work on the introductory portion of [Igneous Rocks II], I was led to publish under the guise of a paper on "Problems in Petrology" (Iddings, 1911), read before the American Philosophical Society in April 1911, a reply to some criticisms of the quantitative system of classification of igneous rocks. Harker had made these criticisms in his book on The Natural History of Igneous Rocks, chiefly regarding [the system's] artificial character as contrasted with the idea of a "natural" system, cherished by some petrographers.The argument was based on the existence of definite quantitative relations between mineral composition and texture on the one hand, and chemical composition of magmas and physical conditions attending their eruption and solidification on the other. These relations rest on the obedience of the component elements to the laws of physical chemistry, and must be capable eventually of definite mathematical expression, although the relationships and the number of variable factors may place the problem beyond the range of exact mathematical formulae. Rock magmas being merely differently mixed solutions of inorganic compounds or salts, there are no inherent or inherited characteristics of form, organism, or immaterial traits, as in living beings. Petrographers, by using such terms as consanguinity, parent magmas, families of rocks, and minerals of first and second generation, have conveyed the idea that there exist among igneous rocks genetic relations analogous to those sustained by living organisms.

ISSN: 0072-1077
EISSN: 2331-219X
Serial Title: Special Paper - Geological Society of America
Serial Volume: 512
Title: Problems
Title: Recollections of a petrologist
Author(s): Iddings, Joseph Paxson
Author(s): Iddings, Joseph Paxson
Author(s): Young, Davis A.editor
Pages: 185-194
Published: 20150611
Text Language: English
Publisher: Geological Society of America (GSA), Boulder, CO, United States
Accession Number: 2015-071681
Categories: Igneous and metamorphic petrology
Document Type: Serial
Bibliographic Level: Analytic
Source Note: Online First
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States
Update Code: 201531
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