Nowadays there is nothing but talk of climate problems and the damage that oil derivatives inflict, for various reasons, to the entire ecosystem. But there is a place in America where black gold has claimed victims for thousands of years, well before we men began to put our own; this place is called "La Brea" and is located in a quiet suburb of Los Angeles, in California.
The “La Brea” tar pits are in fact a natural trap made up of an accumulation of oil, which forms deep pools from a few tens of centimeters to a few meters: but don't be fooled by the shallow depth!
The remains of large mammals have also been found in these pools, like saber-toothed tigers, bears, and even mammoths! Indeed, traces of alteration on the bones found, confirm that even a few inches of this treacherous fluid was enough to trap large mammals, that, in fact, they remained entangled in it until they died of hunger.
This sort of "hell trap" is generated by a natural process of filtration of oil from the ground, that, climbing up through faults and fractures, comes to accumulate on the surface. Here the “lighter” and gaseous components evaporate, leaving only the heavier fraction of the hydrocarbons, this bitumen (essentially composed of asphaltenes).
The “La Brea” tar pits, however, today they are a real mine of fossils from the last ice ages!
One of the properties of bitumen is to perfectly include and preserve the skeletons of animals that end up in it. This ability, albeit of very little consolation for the unfortunate individuals who ended up trapped there, allowed us to find thousands of complete mammalian skeletons, birds, and reptiles from the Upper Pleistocene (in this area, about 40,000 years ago) until today.
The site is home to a natural science museum as well, representing in fact a geological window on the ice ages, it is the subject of specific studies on climate and paleoenvironmental changes.
From now on, be careful where you put your feet!