Highland Rim facts for kids

The Highland Rim is a special area in Tennessee. It's like a big ring of higher land that goes around the Central Basin. The city of Nashville is mostly inside this ring.

Think of the Central Basin as a giant upside-down bowl. Geologists call this a dome. The Highland Rim is like the sloped edge of this bowl, called a cuesta. Where the land suddenly gets much higher, it's called an escarpment. Nashville is in the northwest part of the Central Basin.

Understanding the Land

The Highland Rim is part of a bigger land area called the Interior Low Plateaus. Most of it is in a natural region known as the Interior Plateau. This area is also part of the Eastern Temperate Forest.

People often talk about the Highland Rim in four main parts: Northern, Western, Eastern, and Southern. These divisions help us understand the area better. The word "highland" means it's higher than the basin it surrounds. However, it's usually not more than about 335 meters (1,100 feet) above sea level. The highest points are around 427 meters (1,400 feet). This is unless it's near the Cumberland Plateau, which is even higher.

The land here has many ridges and valleys. There are also some low hills. Lots of streams flow through the region all year long. You might even find some waterfalls. These waterfalls sometimes mark the edge where the Highland Rim meets the Central Basin.

Western Highland Rim Features

The Western Highland Rim starts a few miles west of Nashville. It stretches all the way to the western valley of the Tennessee River. This area is quite hilly. It is cut through by the valleys of the Tennessee River and the Cumberland River.

The rocks under this region are mostly limestone, chert, shale, and sandstone. These rocks formed during the Mississippian period. You can also find older rocks from the Devonian, Silurian, Ordovician, and Cambrian periods. In the northern part, you'll see many sinkholes. This is because the ground is made of limestone that dissolves easily. This area is connected to the Pennyroyal plateau in Kentucky.

Eastern Highland Rim Features

The Eastern Highland Rim begins about 80 kilometers (50 miles) east of Nashville. To its east, the land gets even higher, forming the Cumberland Plateau. Over time, erosion has revealed older carbonate rocks. These rocks formed in the Late Paleozoic era.

These rocks contain different amounts of chert. They are also mixed with fine-grained rocks. This makes them stronger against erosion than the purer limestones below them. The geology here is quite varied. Valley floors are typically limestone, around 152 meters (500 feet) high. Ridges are often sandstone, reaching about 305 meters (1,000 feet). The main rocks include Mississippian-aged St. Louis and Warsaw limestones. Below these are Fort Payne chert and Chattanooga Shale. This shale forms a large part of the escarpment. This area mostly has rolling plains, hills, and karst features.

Northern Highland Rim Features

The Northern Highland Rim starts just a few miles north of Nashville. It extends all the way to the Kentucky border. The region in Kentucky next to it, called the Pennyroyal, is actually a continuation of this same landform. It just has a different name.

Southern Highland Rim Features

The Southern Highland Rim is generally the farthest part from Nashville. In some places, it rises just a few miles north of the border with Alabama. The landforms here are similar to those in nearby parts of Alabama. However, some of the most amazing landforms of the entire Rim can be found in this southern section.

The rocks of the Southern Highland Rim are mostly flat layers of limestone, dolomites, and shales. There are also smaller amounts of cherts, siltstones, mudstones, and very fine-grained to conglomeratic sandstones.

See also

In Spanish: Highland Rim para niños