Published:January 01, 2019
About 2000 years ago, the Mississippi River avulsed westwards and captured the Red River of the South, uprooting vegetation and causing bank instability, resulting in a series of log jams known as the Great Red River Raft. The Great Raft presented a major navigation challenge during the settlement of the Red River Valley from the seventeenth century until its removal in the 1890s. The Great Raft extended c. 100–300 km up-river from Natchitoches, Louisiana to the Louisiana–Arkansas boundary. In the nineteenth century, it contributed to a major military failure by the Union Army and Navy during the 1864 Red River Campaign of the American Civil War. While planning the Red River Campaign, Union commanders made tactical errors by overlooking unique geological aspects of the Red River, including its flashy nature, high sediment load, anastomosing channels and rapids. The Confederates used their knowledge of the Great Raft and the Red River’s morphology to attack the Union’s river fleet while in a position of restricted manoeuverability. The Confederates used the topographically higher defensive positions of natural levee deposits along the Red River to keep the Union’s land and naval forces from supporting each other during the Campaign.
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Military Aspects of Geology: Fortification, Excavation and Terrain Evaluation
This book complements the Geological Society’s Special Publication 362: Military Aspects of Hydrogeology. Generated under the auspices of the Society’s History of Geology and Engineering Groups, it contains papers from authors in the UK, USA, Germany and Austria. Substantial papers describe some innovative engineering activities, influenced by geology, undertaken by the armed forces of the opposing nations in World War I. These activities were reactivated and developed in World War II. Examples include trenching from World War I, tunnelling and quarrying from both wars, and the use of geologists to aid German coastal fortification and Allied aerial photographic interpretation in World War II. The extensive introduction and other chapters reveal that ‘military geology’ has a longer history. These chapters relate to pre-twentieth century coastal fortification in the UK and the USA; conflict in the American Civil War; long-term ‘going’ assessments for German forces; tunnel repair after wartime route denial in Hong Kong; and tunnel detection after recent insurgent improvisation in Iraq.