Geological Influence on the Battle of Gettysburg Essay Example for Free

Geological Influence on the Battle of Gettysburg Essay Battles fought on land have always been influenced by topography as well as geology. Soil conditions, and types and strengths of bedrock are important considerations for building fortifications. Availability of water may determine where military is installed. Mountainous areas may provide cover for guerilla troops. All such topographical and geological considerations combined are studied by military geologists (Haneberg). The information thus gathered is called â€Å"terrain intelligence (Haneberg). † Geology had a major influence on â€Å"[t]he greatest battle of the Civil War,† that is, the Battle of Gettysburg (Copley). Brown describes the area where the battle was fought thus: Each year thousands of sightseers clamber over Little Round Top and Devils Den on the Gettysburg battlefield, and gaze with awe over the mile of treeless plain across which Pickett’s men charged toward â€Å"the little clump of trees† on July 3, 1863. All are impressed by the rocky heights—the Round Tops, Cemetery Ridge, Cemetery Hill, and Culps Hill—against which Lee’s men hurled themselves in vain throughout three days of bitter fighting. Few, however, know that these heights are the outcrop of a diabase sill, appropriately enough called the Gettysburg sill, that about 200 million years ago intruded the Triassic sandstones and shales that floor the broad Gettysburg plain. Even fewer have any concept of the extent to which the movements of the two armies toward Gettysburg, and the battle itself, were influenced by the geology of the region in which the campaign was conducted. The Gettysburg battlefield covers an area of about 15 square miles. The battle, however, was but the climax of a campaign that covered an area of about 11,000 square miles (Brown). The area of the campaign was 140 miles in length, from Fredericksburg on the Virginian river called Rappahannock to Harrisburg on the Pennsylvanian river called Susquehanna; and 80 miles in width, â€Å"from a line drawn on the southeast through Fredericksburg, Washington, and Baltimore, to the northwestern edge of the Great Valley of Virginia, Maryland, and Pennsylvania (Brown). † The Battle of Gettysburg was fought on lowlands of the Triassic Age and â€Å"rocky ridges† that are believed to have been developed on diabase of the early Jurassic Age (Cuffey et al. ). Militarily, the most important hills of diabase were said to have been â€Å"formed on a York Haven Diabase sill running from Culp’s Hill†¦ in the north through Cemetery Hill, Cemetery Ridge, and Little Round Top to Big Round Top†¦ in the south – the Union ‘fishhook’ (Cuffey et al. ). † The Battle of Gettysburg began when Confederate General Lee commanded his troops on to Gettysburg, Pennsylvania, referred to as â€Å"the hub for ten roads (Cuffey et al. ). † This was done in order to drive out the army of the Union from an outcrop of Gettysburg sill (Brown). G. G. Meade responded by marching north and ordering the Federal armies to reach the battlefield (Cuffey et al. ). On the first day of the battle, July 1, 1863, deep cuts on a railroad that was unfinished played an essential role in the action (Copley; Cuffey et al. ). During late afternoon, the Union had to start using the diabase-sill strategically for its defense (Cuffey et al. ). The area where the Union army defended itself was shaped like the hook of a fish (Copley). It extended to the north approximately three miles from the Round Top through the Little Round Top and the Cemetery Ridge to the Cemetery Hill; it also extended south and east to the barb of the area shaped as a fish hook, that is, Culps Hill. The Round Top is known to stand at approximately 785 feet, while the Little Round Top stands at 650 feet above sea level. Between the Cemetery Hill and the Little Round Top, the ridge is said to drop to approximately 570 feet above sea level. The town of Gettysburg itself has an elevation of around 500 feet above sea level (Brown). The fish hook was strategically important on the second day of the battle as well. The Seminary Ridge is â€Å"the trace of a diabase dike,† an offshoot of the Gettysburg sill; it rises approximately 560 feet; but where it rises to the north, it is around 650 feet at the Oak Ridge (Brown). Confederates were positioned on Seminary Ridge before they tried to move across the lowland in order to displace the Union army. The latter moved away from the fish hook before returning to it again as the Confederates had started to gain some ground. In the evening, the Confederates tried to displace â€Å"the Federal right (Cuffey et al. ). † However, â€Å"breastworks of timber† in addition to boulders of diabase on the Culp’s Hill proved themselves almost invincible (Cuffey et al. ). On the third day of the battle, the â€Å"Union center† was heavily bombarded (Cuffey et al. ). The Confederates had launched the attack from their previous position against the Cemetery Ridge. A downpour accompanied this day of the battle. According to Cuffey et al. , â€Å"[d]espite the difficulty of entrenching, crude fences of diabase boulders had provided the Federals with adequate cover in many sectors. † The importance of the diabase sill to the Battle of Gettysburg must be reconsidered in order to understand the outcome of the battle. The diabase sill is resistant; it is closely attached to the surface. As a matter of fact, the bedrock of diabase is so closely attached to the surface that it is virtually impossible for army men to dig in. Stone walls are the only form of protection, for example, rock outcrops and boulders that are isolated. Because the Union army was unable to find a place to thoroughly entrench itself, it suffered a great number of casualties. This was the defending side throughout the Battle of Gettysburg. The Confederates, on the other hand, suffered a greater number of casualties while trying to attack the Union army on the flanks and in the center. Because the Confederates were well-entrenched, they did not lose as many men as the Union army when the latter attacked them (Brown). On July 4, the two armies were burying the men they had lost and succoring those that were suffering from wounds. A day before they had faced each other across the Rapidan River. The bridges across the river had to be rebuilt within ten days before the Confederates could try to cross it. But, as soon as it was made possible to cross the Rapidan River, the armies found themselves facing each other across the river, once again, in the position they had occupied on July 3 (Brown). Geology as well as topography came into focus for a victory another time. The most terrain-intelligent army was, of course, expected to win the ultimate war. Works Cited Brown, Andrew. â€Å"Geology and the Gettysburg Campaign. † Commonwealth of Pennsylvania. Jun 2006. 23 Oct 2008. http://www. dcnr. state. pa. us/topogeo/education/es5/es5. pdf. Copley, Judi. â€Å"The Battle of Gettysberg. † 23 Oct 2008. http://www. scsc. k12. ar. us/2000backeast/trip/members/CopleyJ/Default. htm. Haneberg, William C. â€Å"Geologic and Topographical Influences on Military and Intelligence Operations. † 2008. 23 Oct 2008. http://www. espionageinfo. com/Fo-Gs/Geologic-and-Topographical-Influences-on-Military-and-Intelligence-Operations. html. Cuffey, Roger J. , Robert C. Smith, John C. Neubaum, Richard C. Keen, Jon D. Inners, and Victor A. Neubaum. â€Å"Lee vs. Meade at Gettysburg (July 1-3,1863): The influence of topography and geology on command decisions and battlefield tactics. † Pennsylvania Department of Conservation and Natural Resources and State Tree. 23 Oct 2008. http://www. dcnr. state. pa. us/topogeo/gsaabstr/gettysburg. aspx.