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Natural Bridge Caverns

The Natural Bridge Caverns in San Antonio Texas

The Natural Bridge Caverns is probably the biggest known natural underground caverns in the United States state of Texas. The name itself is derived from a 60 ft wide natural limestone slab bridge which crosses the entrance to the caverns. The slabs were placed in place for the building of this bridge when an existing sinkhole threatened to completely collapse. When this situation arose the bridge was left open for traffic and the sinkhole simply disappeared. Since the original construction of the Natural Bridge Caverns it has become the most visited tourist attraction in San Antonio.

The sinkhole which formed was caused by an underground water flow which occurred due to the presence of naturally occurring limestone in the Natural Bridge Caverns. The limestone is made up of limestone blocks which can move in a certain way, which can be caused by the natural movement of the earth. When this underground water flows under the Natural Bridge and moves downward, it causes the limestone blocks to break up. As a result, small hole results which is known as a sinkhole. This is actually the natural result of the natural movement of the earth.

The sinkhole in San Antonio Texas can be clearly seen on the west side of the Amphitheater area of the Natural Bridge Caverns. A sinkhole like phenomenon can also be observed on the eastern side of the amphitheater. These two entrances to the caverns are at roughly equal distances from one another. Due to the fact that the two areas of the Amphitheater have similar dimensions, the movement of water underneath both areas is approximately the same. As a result, the water eventually fills the sinkholes leaving them both to form the sinkhole known as the sinkhole in San Antonio.

After the natural water movement has filled the sinkhole, it starts to settle into the ground. As this happens, the soil around the sinkhole begins to change as well. As the soil settles around the sinkhole, it forms a compact layer of soil that forms a thick mud layer. As this soil is pushed into the hole created by the water, it pushes against the inside of the hole until it reaches the top. the water inside the sinkhole begins to move upwards causing more water to fill the hole. Eventually the water will move so fast that it can fill the entire bowl of the sinkhole.

Once this occurs, the limestone slabs surrounding the bowl of the sinkhole start to collapse because they have no ability to hold this weight. This causes the rocks and the soil around the bowl to begin to break down. As this occurs, the resulting mass of broken limestone makes its way into the main sinkhole.

All of this is a very interesting natural rock formation that has been caused by the movement of underground water and limestone. What makes this formation truly remarkable is that the collapse was caused by the natural movement of the earth itself. It is a good example of the fact that all natural phenomena in nature can be explained using basic principles.

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