|
Grassy Cove is an enclosed valley in Cumberland County, Tennessee, United States. The valley is notable for its karst formations, which have been designated a National Natural Landmark. Grassy Cove is also home to a small unincorporated community. Grassy Cove is located atop the Cumberland Plateau, approximately east of Crossville and west of the plateau's Walden Ridge escarpment. The mountains that surround the cove are part of the southern fringe of the Cumberland Mountains. The cove is geologically related to the Sequatchie Valley, a large narrow valley stretching just opposite the mountains to the south. Tennessee State Route 68 passes through the northern part of Grassy Cove, providing the valley's only major road access. ==Geology== Grassy Cove is walled in by Brady Mountain to the west, Bear Den Mountain on the east, and Black Mountain to the north. Brady and Bear Den both converge in a V-shaped formation to enclose the cove to the south. Just beyond this convergence, Hinch Mountain— the highest point in Cumberland County— rises to . The southern slopes of Hinch descend drastically to the Sequatchie Valley. The elevation of Grassy Cove is just over , whereas the elevation of the Sequatchie Valley is roughly . Both the Sequatchie Valley and Grassy Cove were part of an anticline that formed as rock strata were bent upward by thrust faulting to form a large ridge during the Paleozoic era (appx. 250 million years ago). During the Mesozoic era, continued erosion along this ridge exposed its younger, more soluble limestone layers. Over subsequent millennia, the limestone dissolved, forming a series of sinkholes that eventually coalesced to create the Sequatchie Valley. Grassy Cove is one such sinkhole that has yet to coalesce with the rest of the Sequatchie Valley.〔Harry Moore, ''A Geologic Trip Across Tennessee by Interstate 40'' (Knoxville, Tenn.: University of Tennessee Press, 1994), 69-70.〕 Grassy Cove is drained entirely by underground streams. The valley's main stream, Grassy Cove Creek, flows northward across the cove before dropping into Mill Cave on the slopes of Brady Mountain. It then winds its way southward through a series of caves before reemerging in the Sequatchie Valley to the south, where it forms the headwaters of the Sequatchie River.〔Moore, 237.〕 Grassy Cove Saltpeter Cave, located on the eastern slope of Brady Mountain, is the eleventh-longest cave in Tennessee and one of the 100 longest caves in the United States.〔Bob Gulden, "(NSS U.S.A Long Cave List )." 25 February 1999. Retrieved: 24 June 2008.〕 Other caves in the cove include Windlass Cave, Bristow Cave, Mill Cave, and Milksick Cave. Sinkhole dimensions:〔Dunigan/Sutherland, (Tennessee sinkholes ) 2013〕 Area: Perimeter: Depth: Volume: Low: High: 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「Grassy Cove」の詳細全文を読む スポンサード リンク
|