Researchers examined minute liquid pockets within minerals using sophisticated microscopes and chemical analyses to learn more about the geochemistry of an inland sea that existed in North America 390 million years ago.
“We realized we can actually draw out information from these mineral structures that could assist enlighten geologic research, such as the chemistry of ancient oceans,” says Sandra Taylor, the paper’s first author. The water contained in the minerals was found to match the chemical composition of an old inland saltwater sea, which the researchers were able to confirm. From Michigan in the US to Ontario in Canada, the sea was in the great lakes region.
This inland sea was home to a coral reef environment comparable to the Great Barrier Reef during the Middle Devonian period. SUV-sized sea scorpions, as well as now-extinct species like trilobites and the forerunners of horseshoe crabs, lived in the waters. After the sea dried up, minerals embedded in sediments were left behind, and these samples were used in the new study. The waters retreated, the biota went extinct, and eventually, the sea dried up.
According to Daniel Gregory, one of the study’s principal authors, “To determine the temperature of the ancient oceans, we analyze mineral deposits. There are millions of years missing from the rock record due to the relative rarity of salt deposits from trapped saltwater, and our current understanding is based solely on a small number of locations where the salt has been found. This method of sampling could provide access to the geologic record spanning millions of years and provide new insights into how the climate has changed through time.” The discovery of embedded seawater bubbles in the pyrite, or fool’s gold mineral, that the researchers were attempting to study, caught them off guard.
Visit us on: thespeednews.com