An international team of scientists has conducted underwater dives in Lake Van in eastern Türkiye to collect microbialite samples as part of a project investigating the origin of tiny carbonate formations that could provide clues for understanding similar environments on Mars.

The lake is known for its historical remains, shipwrecks and microbialites, which are carbonate formations created through interactions between microorganisms and minerals in the water.

As part of the fieldwork, academics dived near the Altınsaç neighborhood in the Gevaş district and collected samples from different depths. The samples will be preserved under suitable laboratory conditions and sent to researchers in different countries for further analysis.

Project coordinator Çetin Yeşilova from Van Yüzüncü Yıl University said the team first identified sampling locations and then determined the depths and frequency of sample collection.

"We took samples from areas we could reach on foot. We went to deeper locations by boat and collected our first samples there,” Yeşilova said.

He said the samples were placed in falcon tubes and preserved with glutaraldehyde before being sent to laboratories for analysis.

"Our aim is to determine the origin of the nanospheres in these microbialites. Once we determine their origin, we want to compare them with samples from Lake Salda and Jezero Crater,” Yeşilova said.

He noted that samples from Mars are not yet available but are expected to arrive in 2029, meaning comparisons with Martian material will be possible after their arrival. In the meantime, researchers will compare the Lake Van samples with material collected from Lake Salda.

Ezher Tagliasacchi from Pamukkale University said the team’s work focused on examining microbialite sites, collecting samples and carrying out field measurements.

Researchers measured the lake’s pH, temperature and dissolved oxygen levels. Tagliasacchi said collecting microbialite samples was one of the most important stages of the fieldwork.

"We successfully completed a dive with the team,” she said.

Miroslaw Slowakiewicz from the University of Warsaw said recent research on Mars had contributed to the scientists’ interest in the study.

He noted that both Lake Van and Lake Salda in Türkiye's southwestern Burdur province have highly alkaline waters, with pH levels close to 10, making them what scientists describe as extreme environments where life is difficult.

The project, led by Van Yüzüncü Yıl University, brings together researchers from Pamukkale University, the University of Warsaw in Poland, the University of Calabria in Italy and the China University of Geosciences.

Supported by Van Yüzüncü Yıl University’s Scientific Research Projects Coordination Office, the study focuses on the origin of carbonate nanospheres found in biofilms developing on active microbialites in Lake Van.