An unexpected instrument gives us new insight into the fine structure of Mars’ outer layers. Using very old meteorites that separated from the red planet about 11 million years ago and were launched into space to eventually land on Earth, scientists uncovered the existence of silicate reservoirs by examining how volcanism shaped Mars’ crust and mantle. accelerated their formation.

This is actually quite challenging work; We have new information about the structure and evolution of Mars, and we don’t need to go all the way to get it. It turns out that Martian meteorites are quite a treasure trove for understanding the planet’s history, and here they are, delivered to our doorstep.

“Martian meteorites are the only physical material we have on Mars,” says geologist James Day of the Scripps Institution of Oceanography.

“They allow us to make precise and accurate measurements and then quantify processes occurring on Mars and near the Martian surface. They provide direct information about the composition of Mars that could inform a real science mission, such as the Perseverance rover’s current operations there.”

The meteorites Day and his colleagues studied come in two forms; chquestites from a stone discovered in Chsigny, France, in 1815, and nakhlites from a specimen discovered in Nahla, Egypt, in 1905.

These two rock types have different compositions. The basalt layer contains augite and olivine minerals. Chquestite consists almost entirely of olivine. Here on Earth, there is more basalt in the crust and olivine in the mantle. The situation is no different on Mars.

After carefully examining and comparing the two types of rocks and their unique chemical properties, researchers were able to determine that they formed in the same volcano approximately 1.3 billion years ago. The difference between them arises from a process called fractional crystallization, in which different conditions cause liquid magma to solidify into different configurations.

Nakhlites were part of the Martian crust; hassinites were part of the mantle below. Additionally, some of the impactors were close enough to the Earth’s crust to interact with and undergo changes in the Martian atmosphere.

“By determining that naclites and hassignites come from the same volcanic system and interact with the Martian crust modified by atmospheric interactions, we can detect a new type of rock on Mars,” Day says.

“Thanks to the current collection of Martian meteorites, all of volcanic origin, we can better understand the internal structure of Mars.”

Interestingly, the two rocks show that volcanism on Mars is both similar and different from volcanism on Earth. Fractional crystallization appears to occur in the same way, producing basaltic rock in the crust and olivine rock in the mantle, as volcanic activity does here.

“The reservoirs on Mars, on the other hand, are extremely old and separated from each other shortly after the formation of the red planet,” Day says. “On Earth, plate tectonics helped reservoirs remix over time. In this sense, Mars provides an important link between the appearance of the early Earth and its appearance today.” The study was published on: Science Developments.