An investigation led by the University of the Azores shows us that the island of Santa Maria, the oldest of the Azores, is the only island in the archipelago that is rising relative to the bottom of the sea, a “rare phenomenon in oceanic islands”, they conclude.
“What our data indicate is that Santa Maria rose in the last 3.5 million years an average of 60 meters per million years, which is six meters in 100 thousand years, 60 centimeters in ten thousand years and six centimeters for every thousand years”, said researcher Sérgio Ávila, from the University of the Azores to Lusa.
Sérgio Ávila, marine biologist and specialist in marine mollusks, professor in the area of Biology of the University of the Azores, who has been leading a multidisciplinary research team for several years. This team is dedicated to the study of the geological evolution of the island of Santa Maria, which is 6.1 million years old.
According to the researcher, “Santa Maria is a box of surprises”, which has allowed researchers to obtain “much scientific data and news”, which are subsequently disclosed to the world in scientific articles published in international journals of geology or paleontology.
“Santa Maria is a very curious case, which is rare on oceanic islands. It is documented in other islands, for example in Cape Verde, but in the case of the Azores, Santa Maria is the only island that has this particular geological history”, he added. His team has published an average of 10 scientific articles per year.
For the investigator, the “only reasonable explanation” for this rare phenomenon on oceanic islands is that “lava that comes from the depths of the oceanic crust at a certain point cannot reach the surface, and these accumulations of magma create a kind of wedge Under the island, causing her to rise”.
Eos magazine, dedicated to the earth sciences, published an article on Santa Maria, noting that the island reversed the descent movement and had begun to rise from the depths of the surrounding ocean. At the base of this news is also a scientific article of the team of Sérgio Ávila, containing the results of this investigation, and was published recently in the journal Bolletin, of the Society of Geology of America.
Santa Maria is a “very particular case”, because “it was once island twice”, explained the researcher. The first time, it disappeared due to the action of the marine erosion, giving rise to a submarine mount of great dimensions. “For about a million years, the island was totally devastated and disappeared. Only the second island has reappeared because of the reactivation of volcanic activity”, he explained, adding that the first island of Santa Maria” sank at an average rate of about 100 meters per million years”.
The history of the geology and fossils of Santa Maria can be seen in a video, about 15 minutes, at the House of Fossils in Vila do Porto, an infrastructure that opened to the public this year in September to publicize this estate and the geological and paleontological heritage of the Azorean island.