The Cumberland Mountains are a
physiographic section of the larger
Appalachian Plateau province, which in turn is part of the larger
Appalachian physiographic division.
Pine Mountain Pine Mountain is a long, narrow ridge starting in northern Tennessee and extending northeastward into southeastern Kentucky and southwestern Virginia. Its southwestern terminus is near
Pioneer, Tennessee, and it extends approximately to the northeast to near the
Breaks Interstate Park in Kentucky and Virginia.
Geology of Pine Mountain Pine Mountain is at the headward ramp of the Pine Mountain Thrust Fault. The hard Lee-type sandstones of the
Early Pennsylvanian form the ridge line. The sandstone strata crop out here because northwestward movement along the
thrust fault caused these sandstones to be pushed up the ramp and over younger strata. Because the sandstones are resistant to erosion, they form a prominent ridge along this ramp. The southwestern terminus of Pine Mountain is marked by the northwest-trending Jacksboro Fault, a lateral ramp fault (part of the Pine Mountain Thrust Fault). The northwestern slope of Pine Mountain is cliff-lined (escarpment slope) whereas the southeastern slope is gentle, this is the
dip slope, and it is roughly parallel to the
dip of the sandstones. This is also the northern limb of the Middlesboro Syncline. Several gaps occur along Pine Mountain, and these are usually caused by erosion along cross-cutting faults. These gaps include the gap at High Cliff, Tennessee (near
Jellico), the Narrows gap at
Pineville, Kentucky, and Pound Gap near
Jenkins, Kentucky. There are other minor gaps as well.
Cumberland Mountain Cumberland Mountain, not to be confused with the Cumberland Mountains within which it resides, is a long ridge extending from northeastern Tennessee, southeastern Kentucky and southwestern Virginia. Its peak forms the boundary between Kentucky and Virginia in some areas. The southeastern side of Cumberland Mountain is a cliff-lined wall that was a barrier to exploration and settlement in Kentucky during the westward expansion in the late eighteenth century. The famous
Cumberland Gap is one of several gaps along Cumberland Mountain that allowed access across the mountain. Cumberland Mountain is a long ridge running from near
Caryville, Tennessee, northeastward to near Norton, Virginia, a distance of approximately . The southeastern slope of the ridge is cliff lined, whereas the northwestern slope is more gentle. The ridge is interrupted by several gaps, including Cumberland Gap, Big Creek Gap between Ivydell and
LaFollette, Tennessee, Pennington Gap near
Pennington Gap, Virginia, and Big Stone Gap near
Big Stone Gap, Virginia. The crest of Cumberland Mountain ranges from to in elevation. Cumberland Mountain is roughly parallel to Pine Mountain which lies from eight to ten miles to the northwest.
Geology of Cumberland Mountain Cumberland Mountain is part of the Cumberland Overthrust Sheet or block and is the northern limb of the Powell Valley Anticline, a ramp
anticline. The ridge exists because hard Lee-type sandstones of Early Pennsylvanian Age crop out along this line. Softer rocks have been eroded away, leaving the resistant sandstones to form a ridge. The southwestern terminus of Cumberland Mountain is marked by the northwest-trending Jacksboro Fault, a lateral ramp fault (part of the Pine Mountain Thrust Fault). The northwestern terminus is located near Norton, Virginia, where the hard sandstones dip below the surface as the axis of the Powell Valley anticline plunges to the northeast. The various gaps in Cumberland Mountain are caused by rock weaknesses at cross-cutting faults or joints. For example, Cumberland Gap was caused by erosion along the cross-cutting
Rocky Face Fault. The cliff-lined southeastern slope (escarpment slope) of Cumberland Mountain was created by erosion along the breached side of the Powell Valley Anticline. The more-gentle northwestern slope is the dip slope and roughly parallel to the dip of the Early Pennsylvanian sandstones. This northwestward dip is the northern limb of the Powell Valley Anticline. Cumberland Mountain forms the drainage divide between the Cumberland River to the north and the Powell River to the south.
Synclinal mountains Several mountains that lie between Pine Mountain and Cumberland Mountain include
Black Mountain and Little Black Mountain as well as a number of smaller mountains (Short, Walnut, Rich, Log, Reynolds, etc.). These are all
synclinal mountains and reside along the axis of the northeast-trending Middlesboro Syncline. The Pine Mountain ramp forms the northwestern limb of this syncline and Cumberland Mountain (the northwestern limb of the Powell Valley Anticline) forms the southeastern limb. ==See also==