PORTUGAL -- It was in 1969 when the country was hit by an earthquake that caused a tsunami to occur. Over a dozen people were killed during the disaster.

However, that was not the first disaster to take lives. In fact, about 200 years before that, an even larger earthquake was recorded to hit the same area. It killed roughly 100,000 people while destroying Lisbon, the central city of Portugal.

The two earthquakes that happened in the same city and the same area was not really a cause of alarm for seismologists. Such an occurrence is somewhat a common phenomenon. However, what puzzled the experts was that the two large earthquakes started their tremors in the flatbeds of the oceans - far from the tectonic cracks, where movements of the earth's crust are expected to slip past each other, naturally causing earthquakes.

Since the area was supposed to be quiet and not an expected location for rumbles and tremors to happen, scientists started to study the possibility that the tectonic plates could be peeling into two varying layers -- where the top is seen as peeling off from its bottom part. This phenomenon has never been spoken of before until a group of researchers presented the fact to the European Geosciences Union Assembly then held in Vienna in April. The peeling is believed to be creating a new subzone which means that a tectonic plate is rammed against another tectonic plate just below it.

According to National Geographic, the middle layer of the tectonic plate absorbs water, causing such peeling to happen. The said middle layer is believed to have undergone serpentinization. This is a geological process when water is seen seeping through cracks that cause the layer to transform into green minerals that are considered soft in nature. Such peeling could trigger the subduction zone that causes the unexplainable earthquake, National Geographic explains.

The group the first to lobby the idea. However, they are the first one who was able to provide supporting details to this claim. They conducted tests on two-dimensional models to check on their hypothesis. The preliminary results show that it is indeed possible for a perfectly stable plate to peel off its top and bottom layer.

Although the models show that there is a possibility for the theory, it is yet to be proven right. As of the moment, the research has not been published in any scientific journals.