An island rises from the waters, then disappears, as if it had never existed. In the Caspian Sea, this phenomenon has been repeated for more than a century, defying expectations and captivating scientists. These cyclical appearances and disappearances, observed since 1861, raise an intriguing question: what invisible force orchestrates this natural ballet?
25 kilometers from the coast of Azerbaijan, an ephemeral island recently made a comeback, before disappearing again beneath the waves. NASA satellites captured this astonishing spectacle, revealing a 400 meter wide island born in February 2023. But this appearance is just one episode in a series of cycles.
The appearance of an ephemeral island
In February 2023, an unexpected island appeared 25 kilometers off the coast of Azerbaijan. Satellites Landsat 8 and 9 documented its formation, revealing a structure 400 meters wide. This island, named Chigil-Deniz, is the result of an eruption of the Kumani Bank mud volcano, a unique geological phenomenon.
As soon as it was formed, the island began to disappear due to marine erosion. Recent images show that it has almost entirely been swallowed up by water. This cycle of appearance and disappearance is not new: similar events have been recorded since 1861, with islands emerging and then disappearing within months.
The role of mud volcanoes
Mud volcanoes, like Kumani Bank, form when fluids beneath pression rise to the surface, carrying sediments and gases. These eruptions can create temporary islands, but these are quickly destroyed by waves. Azerbaijan, located in the junction of the Arabian and Eurasian plates, is home to more than 300 of these geological structures.
These mud volcanoes are often accompanied by plumes of sediment visible from space. Their activity, although less spectacular than that of traditional volcanoes, plays a key role in the geodynamics of the region. Scientists study these phenomena to better understand their impact on the environment.
A phenomenon still poorly understood
Scientists are seeking to understand the precise mechanisms behind these eruptions. Two hypotheses are put forward: the activity tectonic intense in the region where the combustion spontaneous release of gases. This research could shed light on similar phenomena observed on Mars, where comparable structures have been identified.
-Studying these mud volcanoes could also reveal information about natural gas reserves in the region. Eruptions, although unpredictable, provide a unique window into geological processes at depth.
A window into Earth dynamics
The ghost island of Caspian Sea reminds us that the Earth is constantly evolving. These events, although spectacular, highlight the importance of studying geological processes to better understand our planet and its mysteries.
Satellites continue to monitor the region, capturing every detail of these ephemeral phenomena. These observations allow scientists to better anticipate future eruptions and enrich our knowledge of terrestrial geology.
To go further: What is a mud volcano?
A mud volcano is a geological formation that ejects mud, gases and water rather than lava. These structures form when pressurized fluids rise to the surface, pushing sediments and creating mounds or craters. Unlike traditional volcanoes, they are not linked to magmatic activity. Mud volcanoes are often associated with tectonically active areas, such as plate boundaries. In Azerbaijan, for example, more than 300 mud volcanoes have been recorded. Their activity can vary, from small muddy eruptions to spectacular explosions releasing flames and flammable gases.
These phenomena are studied for their role in the release of natural gases, such as methane. They also offer clues to geological processes at depth, including the migration of fluids in sedimentary layers. Some scientists believe similar structures could exist on Mars.
Although less destructive than conventional volcanoes, mud volcanoes can have a significant local impact. Their eruptions can modify landscapes, create ephemeral islands and influence surrounding ecosystems. Their study continues to reveal valuable information about the dynamics of our planet.
