The Natural History of Igneous Rocks [Paperback]

A thorough and illustrated account by a prominent Cambridge petrologist about the formation, structure and classification of igneous rocks.Based on his Cambridge lectures, this work by the petrologist Alfred Harker (18591939) offers an introduction to the development of rocks. Over the course of the work, he discusses vulcanicity, rock structure, crystallization, the role of magma and principles of rock classification, aided by more than one hundred diagrams.Based on his Cambridge lectures, this work by the petrologist Alfred Harker (18591939) offers an introduction to the development of rocks. Over the course of the work, he discusses vulcanicity, rock structure, crystallization, the role of magma and principles of rock classification, aided by more than one hundred diagrams.Alfred Harker (18591939) was a prominent petrologist who spent his career at St John's College, Cambridge, lecturing on and researching rock formations and related geological activity. He was elected a fellow of the Royal Society in 1902, and was president of the Geological Society from 1916 to 1918. He used his Cambridge lectures as the foundation for this book (first published in 1909), offering an introduction to the development of rocks and related volcanic activity. With more than one hundred diagrams of various aspects of geological formations, this work also provides a visual guide to the location and formation of igneous rocks. Over the course of the work, he covers the themes of vulcanicity, rock structure, crystallization, the role of magma and the principles of rock classification, giving a broad picture of the field of petrology around the beginning of the twentieth century.Preface; 1. Igneous action in relation to geology; 2. Vulcanicity; 3. Igneous intrusion; 4. Petrographical provinces; 5. Mutual relations of associated igneous rocks; 6. Igneous rocks and their constituents; 7. Rock-magmas; 8. Crystallization of rock-magmas; 9. Supersaturation and deferred crystallization; 10.lc%