Morocco.. 515-Million-Year-Old Fossils Found Preserved in Volcanic Deposits
A team of researchers led by Professor Abdelrazak El Albani, a professor-researcher at the Institute of Chemistry of the Environment and Materials in Poitiers, has discovered two new species of trilobites in Morocco, in the Aït Youb region of Souss-Massa.
These discoveries are of exceptional scientific importance, as these trilobites, articulated marine creatures that lived millions of years ago, are the first marine fossils to have been found fully preserved in the world. These fossils date back 515 million years and offer a rare glimpse into the marine ecosystem that prevailed at that time.
The preservation conditions of these fossils are reminiscent of a marine “Pompeii”, as they were buried under layers of volcanic ash, which allowed them to be perfectly preserved. The results of this discovery have been published in the prestigious American journal “Science”, which confirms their great scientific value and their importance for understanding the history of life on Earth.
For Professor El Albani, “this discovery shows for the first time the essential role of underwater volcanic deposits in the preservation of fossils and the importance of exploring volcanic marine environments”. The discovery also shows that “the non-destructive imaging technique, high-resolution X-ray microtomography (XRµCT), is a powerful tool that allows fossilized bodies to be visualized in three dimensions inside hard rocks without risk of damaging them”. Scientists were able to create casts of the missing bodies with an astonishing level of detail by digitally filling in the spaces left by the creatures.
“Thanks to this discovery, volcanic deposits should become a new target for study due to their exceptional ability to trap and preserve biological remains, even the softest ones, without causing the deterioration that generally leads to loss or even destruction of samples,” added the professor. He also noted that these discoveries “open new windows into the past of our planet”.
Explaining this discovery, the research team pointed out that volcanoes located at the boundaries of tectonic plates are known for their violent large-scale eruptions, which can produce tens of cubic kilometers of material. These eruptions can trap existing life almost instantaneously, preserving under their ashes the vestiges of entire civilizations, as in Santorini and Vesuvius.
The team confirmed that trilobites, with more than 22,000 discovered species covering the Paleozoic era (-539 to -252 million years), are undoubtedly among the most famous fossil invertebrates. While their calcite exoskeleton gives them a great capacity for fossilization, which explains their abundance in the fossil record, their non-mineralized appendages and internal organs have only been identified from a limited number of samples.
The same source added that “during a volcanic eruption in Aït Youb, 515 million years ago, the living organisms present were buried under thick volcanic clouds. The intense heat consumed the biological tissues, leaving cavities in the hardened ash, i.e., molds of the organisms”.
This study, according to the statement, “sheds new light on the anatomical organization of trilobites, particularly the cephalic part”. For the first time in this category of fossil arthropods, the presence of a labrum, a soft mouthpart that serves as an upper labrum in modern arthropods, has been detected, which helps to resolve a debate that has been going on for over a century.
The research team stressed that due to the global importance of the study site, it would be necessary and crucial to protect it by classifying it as a UNESCO World Heritage Site.
