Mass Extinction 5- Cretaceous-Tertiary Extinction
Cretaceous refers to the geological characteristics more than 65 million years ago. There is a gap of about 149 years since the 4th mass extinction that ended the Triassic period. During this time, geological changes of the Earths’ physical surface included the surfacing of far-reaching beds of chalks. The Earth’s large mass of land was still in the process of breaking up into continents. Before the end of this period, the bodies of water known today as the Atlantic Ocean widened and completed the breaking down of the supercontinents. This brought forth the continents of Australia, Antarctica, Africa and South America, but they were still not in the same position they are presently in. India and Madagascar were still parts of Africa during this period.
The climate during the Cretaceous era was said to be warm and the Polar Regions still had no permanent ice. The intense warmth was linked to the massive lava deposits in the area known as Deccan Trap, found in the region known today as India. During the Cretaceous period, the land was still dominated by dinosaurs; although marine animals also thrived.
The last of the 5 mass extinctions, the Cretaceous mass extinction, was supposed to have been caused by a comet or asteroid that hit Mexico’s Yucatan Peninsula which became buried beneath the Gulf of Mexico. The evidence that supports this theory was the indentation it made upon impact. Today, said indentation is called the Chicxulub crater and measures about 112 miles wide. The intensity of the impact created by a huge heavenly body expelled particles that rose into the air and soared into the atmosphere, which reached every corner of the Earth. As a result, the Earth did not receive adequate solar radiation for quite some time, which disrupted the Earth’s ecology. This subsequently caused the natural food chain to collapse and led to the fifth mass extinction.
Recent studies by scholars and scientists have replaced the asteroid/comet theory with the same volcanic eruption theories in the previous periods. The Deccan Traps located in the Indian area, was said to release floods of basalt liquid lava. Basalt is characterized by gas discharges that produced fountains of fire and incandescent lava. Hence, the occurrence of atmospheric changes that brought global warming and climate change. This caused the greatest mass extinction of all, where 70% of the Earth’s inhabitants including the dinosaurs were pushed into extinction.
By sorting out all of this information, many are inclined to believe the theory about volcanic eruptions as the more logical explanation. The possibility of asteroids and comets hitting the Earth in the 5 mass extinctions are possibly true but doubtful to have created a catastrophic impact. Most of the meteorites found on the Earth’s surface were not large enough to create a catastrophe that could affect the atmosphere. Studies show that their speed decelerates once they enter the Earth’s atmospheric layers.
What is frightening of course, is the similarity of the scenarios in the 5 mass extinctions to what is actually happening today. Mankind may have sped up global warming with their activities but everything is still at an unpredictable stage. Perhaps, we should also take into mind a religious tenet in relation to anticipated mass extinctions. All we need to be is prepared, since we will have no way of knowing when it will happen. “It will come like a thief in the night".
- Revelation 3:3
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