Geology Archives

March 1, 2022March 1, 2022 by Nicholas Castle

A Mars Meteorite Shows Evidence of a Massive Impact Billions of Years ago

This artist’s impression shows how Mars may have looked about four billion years ago. The young planet Mars would have had enough water to cover its entire surface in a liquid layer about 140 metres deep, but it is more likely that the liquid would have pooled to form an ocean occupying almost half of Mars’s northern hemisphere, and in some regions reaching depths greater than 1.6 kilometres. Credit: ESO/M. Kornmesser

Researchers at Australia’s Curtin University have discovered evidence of a massive impact on the Martian surface after 4.45 billion years ago. This may not seem like a surprising revelation – after all, we know that there were several large impacts on Mars, like Hellas and Argyre, and we know that large impacts happened frequently in the early solar system – so why is this a big deal?

January 20, 2022January 20, 2022 by Evan Gough

The Moon’s Crust was Formed From a Frozen Slushy Magma

Magma ocean and first rocky crust on the Moon. Image Credit: NASA/Goddard Space Flight Center

Scientists’ detailed study of the Moon dates back to the Apollo missions when astronauts brought rock samples from the lunar surface back to Earth for analysis. Apollo 11 gathered samples from the lunar highland regions, the pale areas on the Moon’s surface easily seen from Earth. The highlands are made of a relatively light rock called anorthosite, which formed early in the history of the Moon, between 4.3 and 4.5 billion years ago.

There’s some mystery involved in the anorthosite formation on the Moon. The age of the anorthosite highlands doesn’t match how long it took for the Moon’s magma ocean to cool. But scientists behind a new study think they’ve solved that mystery.

January 17, 2022January 17, 2022 by Evan Gough

Remember When Life was Found in a Martian Meteorite? Turns out, it was Just Geology

The Alan Hills meteorite is a part of history to Mars aficionados. It came from Mars and meteorite hunters discovered in Antarctica in 1984. Scientists think it’s one of the oldest chunks of rock to come from Mars and make it to Earth.

The meteorite made headlines in 1996 when a team of researchers said they found evidence of life in it.

Did they?

December 13, 2021December 13, 2021 by Matt Williams

One Feature Mars has That we Don’t: Polar Megadunes

For fans of astrophotography, Kevin M. Gill needs no introduction. Even if you’re not up on the latest astronomical news and developments, chances are you’ve still seen some of his images over the years. From beautiful artist renditions to breathtaking photographs of far-off planets, Gill has covered it all. Among the latest images available on his official Flickr page are pictures of a unique feature on Mars: the Chasma Boreale Megadunes!

November 30, 2021November 30, 2021 by Evan Gough

InSight Peers Deep Below the Surface on Mars

Artist's concept of InSight "taking the pulse of Mars". Credit: NASA/JPL-Caltech

The InSight lander has been on Mars, gathering data for a thousand days now, working to give us a better understanding of the planet’s interior. It’s at Elysium Planitia, the second largest volcanic region on Mars. A newly-published paper based on seismic data from the lander shows something unexpected underground: a layer of sediment sandwiched between layers of lava flows.

October 17, 2021October 17, 2021 by Matt Williams

Volcanism on the Moon Ended About 2 Billion Years ago

According to the most widely accepted theories, the Moon formed about 4.5 billion years ago after a Mars-sized object (Theia) collided with Earth. After the resulting debris accreted to create the Earth-Moon system, the Moon spent many eons cooling down. This meant that a few billion years ago, lakes of lava were flowing across the surface of the Moon, which eventually hardened to form the vast dark patches (lunar maria) that are still there today.

Thanks to the samples of lunar rock brought back to Earth by China’s Chang’e 5 mission, scientists are learning more about how the Moon formed and evolved. According to a recent study led by the Chinese Academy of Geological Sciences (CGAS), an international team examined these samples to investigate when volcanism on the Moon ended. Their results are not only filling in the gaps of the Moon’s geological history but also of other bodies in the Solar System.

September 22, 2021September 23, 2021 by Nancy Atkinson

3,600 Years ago, a 50-Meter-Wide Meteor Exploded in the Sky and Destroyed a City Near the Dead Sea

This is an artist’s depiction of a 10-kilometer (6-mile) diameter asteroid striking the Earth. New evidence in Australia suggests an asteroid 2 to 3 times larger than this struck Earth early in its life. Credit: Don Davis/Southwest Research Institute.

An archeological dig has uncovered evidence of a massive cosmic airburst event approximately 3,600 years ago that destroyed an entire city near the Dead Sea in the Middle East. The event was larger than the famous Tunguska airburst event in Russia in 1908, with a blast 1,000 times more powerful than the Hiroshima atomic bomb. The event flattened the thriving city of Tall el-Hammam, located in what is now Jordan.

August 6, 2021August 6, 2021 by Matt Williams

Animals Could Have Been Around Hundreds of Millions of Years Earlier Than Previously Believed

Credit: Elizabeth Turner/Laurentian University

According to the most widely accepted theories, evolutionary biologists assert that life on Earth began roughly 4 billion years ago, beginning with single-celled bacteria and gradually giving way to more complex organisms. According to this same evolutionary timetable, the first complex organisms emerged during the Neoproterozoic era (ca. 800 million years ago), which took the form of fungi, algae, cyanobacteria, and sponges.

However, due to recent findings made in the Arctic Circle, it appears that sponges may have existed in Earth’s oceans hundreds of millions of years earlier than we thought! These findings were made by Prof. Elizabeth Turner of Laurentian University, who unearthed what could be the fossilized remains of sponges that are 890 million years old. If confirmed, these samples would predate the oldest fossilized sponges by around 350 million years.

February 25, 2021February 25, 2021 by Evan Gough

What a Geologist Sees When They Look at Perseverance’s Landing Site

A topographic map of the region around Jezero Crater. Image Credit: ESA/DLR/FU CC BY-SA 3.0 IGO

Geologists love fieldwork. They love getting their specialized hammers and chisels into seams in the rock, exposing unweathered surfaces and teasing out the rock’s secrets. Mars would be the ultimate field trip for many of them, but sadly, that’s not possible.

Instead, we’ve sent the Perseverance rover on the field trip. But if a geologist were along for the ride, what would it look like to them?

January 21, 2021January 21, 2021 by Evan Gough

Mars has Been Through Many Ice Ages in the Last Billion Years

Deuteronilus Mensae (DM)has many rough surface features. The Mars Reconnaissance Orbiter has shown that many areas in DM are sub-surface glaciers covered by a thin layer of debris. Image: NASA/JPL/University of Arizona

Like Earth, Mars has experienced periods of extreme glaciation or ice sheet coverage, which are known as ice ages. As these ice ages come and go, glaciers expand and contract along the planet’s surface, grinding huge boulders down to smaller rocks. By examining the size of boulders and rocks at specific locations on Mars, we should be able to understand the history of the Martian ice ages.

A new study did just that.