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Geology of the Lewis and Clark Trail in North Dakota

John W. Hoganson and Edward C. Murphy, 2003, Mountain Press, Missoula, USA, 247 p. (Softcover, US $18.00) ISBN: 0-87842-476-8.

Two-hundred years ago, on May 14, 1804, the Corps of Discovery, led by Captains Meriwether Lewis and William Clark, 29 and 33 years-old respectively, pushed off from the bank of the Missouri River at St. Charles, Missouri, on a two-year and four-month exploration of the largely uncharted lands of the newly purchased Louisiana Territory and the unclaimed wilderness beyond the continental divide to the Pacific Ocean. Lewis and Clark followed in the wake of the explorations of the length and breadth of the Pacific Ocean by Captain James Cook, which ended 35 years earlier with Cook's death on the shore of Kealakekua Bay, Hawaii.

John Hoganson and Ed Murphy's book, Geology of the Lewis and Clark Trail in North Dakota, is an insightful account of the expedition's route through North Dakota, and the landscape, surficial deposits, and bedrock that the captains described. Hoganson and Murphy are eminently qualified to write this account of the geology of the Lewis and Clark Trail in North Dakota. As geologists with the North Dakota Geological Survey, they have over 40 collective years of mapping the bedrock and surficial geology of the state. Their research for the book has been of the highest quality, and the persons with whom they consulted, and the bibliography that they assembled, are excellent.

The book is divided into five parts: (1) Jefferson's vision for the expedition and his choice of Meriwether Lewis to lead the enterprise; (2) a concise yet thorough, well-illustrated discussion of the general geology of North Dakota through time, written for the layperson; (3) a section on the Missouri River that includes a discussion of the pre-glacial drainage system and the changes that glacial advances and retreats …