With the rise of factory production, many new substances have been poured into the environment. In urban areas, the byproducts of cars and washing machines are pumped out through pipes into waterways, causing increased pollution.

When black ooze started to emerge from the roads of Venezuela, residents initially thought nothing of it. But when La Mancha Negra claimed lives and damaged properties, everyone was convinced it might be due to something alarming.

Blob of Sticky Goo

La Mancha Negra (The Black Stain) is a strange phenomenon that began in 1986 in the City of Caracas in Venezuela. On a main highway between the city and its airport, a strange oily substance seeps through the road's asphalt on a 50-yard (46-meter) stretch. The first people who picked up on it were road workers attending to the road into Caracas' international airport.

The mysterious substance was given little notice, but it eventually grew and spread. The black goo spread at a rapid rate until 8 miles (13 kilometers) of the road got covered by it. The ooze showed no signs of stopping and seemed to grow with the weather changes.

According to the observers, La Mancha Negra was a thick and mangled black blob, making the road difficult to drive on. Government authorities claimed it is partially made of dust and oil while the rest consists of manmade materials.

As the blob spreads, it has become a hazard for motorists, causing countless car crashes. After five years, La Mancha Negra had spread throughout the capital city and had been linked to almost 1800 deaths. It was then that the Venezuelan government was forced to intervene.

Authorities tried cleaning the road by spraying it with a pressure wash and allowing the rain to chip away. Unfortunately, none of these methods worked. They consulted multiple experts and even tried dumping pulverized limestones on the road, only to create more problems as the dust entered the air. All of a sudden, the black goo mysteriously disappeared just as it had appeared. Less than five years later, La Mancha Negra resurfaced on Venezuelan roads.

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Possible Causes of the Black Stain

There have been several explanations surrounding La Mancha Negra, but only two theories are accepted by many. The first theory fits into the historical narrative, suggesting that the Black Stain is simply a bad asphalt batch. This assumption is supported by the fact that asphalt contains tar (goo) base, which can change in consistency.

Tar can also get slick under hot, sunny conditions. The final evidence points to the fact that the phenomena occurred only in a single location, making the theory of a bad batch of asphalt possible.

The second theory claims that La Mancha Negra is just natural seepage. Proponents of this theory refer to the large petroleum deposits of heavy crude near Caracas, in a place called the Orinoco Belt. However, this reason is considered weak because there must be a central point where the pressure breaks through the surface of the Earth. Aside from this, heavy crude usually sinks, so excess seepage seems impossible to happen.

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