New research supports theorized intermittent ocean exiting Mars’ giant Valles Marineris canyon
Theorized ocean from 2019 & 2022 papers
Scientists studying the deltas of debris that exist at the base of the cliffs inside Mars’ giant Valles Marineris canyon have concluded the deltas suggest the existence of an ocean there about three billion years ago.
The theorized ocean on the map to the right comes from research published in 2019, with additional support published in 2022. This new work supports those conclusions. From the press release:
At the lower end of the canyon system, so-called “scarp-fronted deposits” were discovered, which are interpreted as “fan deltas”. Fan deltas form where a fan-shaped cone of debris and sand grows directly into a standing body of water. The researchers found that the structures mapped on Mars are very similar to classic deltas on Earth.
…The results also show that the ocean found was at least as large as the Arctic Ocean on Earth. Schlunegger says: “We are not the first to postulate the existence and size of the ocean. However, earlier claims were based on less precise data and partly on indirect arguments. Our reconstruction of the sea level, on the other hand, is based on clear evidence for such a coastline, as we were able to use high-resolution images.”
You can read the new paper here [pdf]., which I strongly suggest as the press release at the link above is very poorly written. The 2019 and 2022 work focused on computer models and the geological features in the region of the theorized ocean, including evidence of possible past tsumanis. This new research focuses on the debris piles at the base of Valles Marineris’ cliffs, all of which appear to end at similar elevations. As this new paper notes:
Figure 7 from today’s paper. Orange line indicates shoreline
Fan-delta structures recording evidence for shorelines in the same elevation range as in Coprates Chasma are preserved in Capri Chasma, Chryse Chaos, and Hydraotes Chaos (Fig. 7). This indicates deposition during a period of a sea-level highstand extending from Valles Marineris to the Northern Lowland. In all these areas, no evidence for break-in- slopes at a higher elevation than the range between −3750 and −3650 m is found, suggesting that this was possibly the highest level reached by the sea. Our inferred coastal margin in this elevation range is supported by the occurrence of break-in-slopes in West Deuteronilus Mensae [on the other side of the planet].
Comparing the 2019 map above with this new map, the theorized shorelines are reasonably similar, though there are differences.
What is not yet determined is how long this ocean existed, and what role ice might have played in that existence. Other recent research in Gale Crater suggests a cap of ice on this ocean might have allowed it to exist for long periods, even though Mars is too cold with too thin an atmosphere for liquid water to flow. It is also possible the ocean came and went, laid down repeatedly by catastrophic floods, only to sublimate away each time relatively quickly in terms of geological time.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Theorized ocean from 2019 & 2022 papers
Scientists studying the deltas of debris that exist at the base of the cliffs inside Mars’ giant Valles Marineris canyon have concluded the deltas suggest the existence of an ocean there about three billion years ago.
The theorized ocean on the map to the right comes from research published in 2019, with additional support published in 2022. This new work supports those conclusions. From the press release:
At the lower end of the canyon system, so-called “scarp-fronted deposits” were discovered, which are interpreted as “fan deltas”. Fan deltas form where a fan-shaped cone of debris and sand grows directly into a standing body of water. The researchers found that the structures mapped on Mars are very similar to classic deltas on Earth.
…The results also show that the ocean found was at least as large as the Arctic Ocean on Earth. Schlunegger says: “We are not the first to postulate the existence and size of the ocean. However, earlier claims were based on less precise data and partly on indirect arguments. Our reconstruction of the sea level, on the other hand, is based on clear evidence for such a coastline, as we were able to use high-resolution images.”
You can read the new paper here [pdf]., which I strongly suggest as the press release at the link above is very poorly written. The 2019 and 2022 work focused on computer models and the geological features in the region of the theorized ocean, including evidence of possible past tsumanis. This new research focuses on the debris piles at the base of Valles Marineris’ cliffs, all of which appear to end at similar elevations. As this new paper notes:
Figure 7 from today’s paper. Orange line indicates shoreline
Fan-delta structures recording evidence for shorelines in the same elevation range as in Coprates Chasma are preserved in Capri Chasma, Chryse Chaos, and Hydraotes Chaos (Fig. 7). This indicates deposition during a period of a sea-level highstand extending from Valles Marineris to the Northern Lowland. In all these areas, no evidence for break-in- slopes at a higher elevation than the range between −3750 and −3650 m is found, suggesting that this was possibly the highest level reached by the sea. Our inferred coastal margin in this elevation range is supported by the occurrence of break-in-slopes in West Deuteronilus Mensae [on the other side of the planet].
Comparing the 2019 map above with this new map, the theorized shorelines are reasonably similar, though there are differences.
What is not yet determined is how long this ocean existed, and what role ice might have played in that existence. Other recent research in Gale Crater suggests a cap of ice on this ocean might have allowed it to exist for long periods, even though Mars is too cold with too thin an atmosphere for liquid water to flow. It is also possible the ocean came and went, laid down repeatedly by catastrophic floods, only to sublimate away each time relatively quickly in terms of geological time.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News