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Cuyamaca Rancho State Park is a state park in California, USA, located east of San Diego in the Laguna Mountains of the Peninsular Ranges. The park's feature pine, fir, and oak forests, with meadows and streams that exist due to the relatively high elevation of the area compared to its surroundings. The park includes Cuyamaca Peak, the second-highest point in San Diego County. Park amenities include trails for hiking, horseback riding, and mountain biking, as well as campgrounds for family, group, equestrian, and primitive trail camping; as well as an exhibit at a former gold mine, the Stonewall Mine. Wildlife in the area includes mountain lions, which have been known to attack humans, and park literature emphasizes avoiding encounters with them. Numerous other species of mammals, birds, reptiles, and amphibians are known to reside within the park. The park was closed for several months due to massive damage incurred in the 2003 Cedar Fire. Although much of the forest was burned, the park has since been reopened and the fire ecology regenerating native plants are re-growing and returning. == Geology == Cuyamaca Rancho State Park is located in the Peninsular Range, which extends from the San Jacinto Mountains north of the park, southward to the tip of Baja California. At the western edge of the most seismically active area in North America, the range is a great uplifted plateau, cut off from the Colorado Desert to the east by the Elsinore Fault Zone, where vertical movement over the last two million years has amounted to thousands of feet of tectonic uplift. Metamorphosed sediments such as schist, gneiss, and quartzite are abundant in the Cuyamacas, particularly in the Stonewall Mine area. Most of the rocks now seen in the park are plutonic: either the granodiorite comprising Stonewall Peak, or the gabbro comprising Cuyamaca Peak. As these bedrocks weather, they become the parent material of the coarse, acidic, red soil found throughout the area. Gabbro weathers to a darker red soil than granodiorite or other quartz-rich rock. Gold is a natural element that appears around granite formations because gold forms during cooling and solidification of igneous rock. Gold commonly occurs in association with quartz, either as pure gold or as an ore. In the Cuyamaca area, gold is associated with the metasediment called Julian Schist. At mines in this area, including the Stonewall, veins of gold were followed into the bedrock and the surrounding ore excavated. Most streams in the park have small amounts of gold, since it is constantly being removed from the quartz exposures by weathering. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cuyamaca Rancho State Park」の詳細全文を読む スポンサード リンク
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