Jump to content
Join the Unexplained Mysteries community today! It's free and setting up an account only takes a moment.
- Sign In or Create Account -

When were sea levels highest?


Still Waters

Recommended Posts

Sea levels are rising as climate change rapidly melts glaciers and ice sheets and the water within the oceans expands in a warming world. But have sea levels ever been higher than they are today? And when were they the highest?

In short, sea levels have easily been higher than they are today. But it's still unclear exactly when they were at their highest, although scientists have a few ideas.

Within the past half-billion years, sea levels likely peaked 117 million years ago, during the Aptian age. At this time, which was part of the Cretaceous period (145 million to 66 million years ago), sea levels were around 700 feet (200 meters) higher than they are today, according to a 2022 study in the journal Gondwana Research

"Over the past 540 million years, the highest sea levels were in the Cretaceous, at the time when the dinosaurs were walking the Earth," 

https://www.livescience.com/planet-earth/climate-change/when-were-sea-levels-highest

  • Like 3
  • Thanks 6
Link to comment
Share on other sites

 
2 minutes ago, Still Waters said:

Sea levels are rising as climate change rapidly melts glaciers and ice sheets and the water within the oceans expands in a warming world. But have sea levels ever been higher than they are today? And when were they the highest?

In short, sea levels have easily been higher than they are today. But it's still unclear exactly when they were at their highest, although scientists have a few ideas.

Within the past half-billion years, sea levels likely peaked 117 million years ago, during the Aptian age. At this time, which was part of the Cretaceous period (145 million to 66 million years ago), sea levels were around 700 feet (200 meters) higher than they are today, according to a 2022 study in the journal Gondwana Research

"Over the past 540 million years, the highest sea levels were in the Cretaceous, at the time when the dinosaurs were walking the Earth," 

https://www.livescience.com/planet-earth/climate-change/when-were-sea-levels-highest

Have we not been given enough water so that we can colonise Mercury, Venus, the Moon, and Mars?

  • Confused 2
Link to comment
Share on other sites

On 3/25/2024 at 11:55 AM, Still Waters said:

But have sea levels ever been higher than they are today?

Yes.  During the Yarmouth Interglacial they were as much as 20 feet above modern.

Doug

  • Like 4
Link to comment
Share on other sites

On 4/1/2024 at 11:22 AM, Doug1066 said:

Yes.  During the Yarmouth Interglacial they were as much as 20 feet above modern.

Doug

I thought the concept of the Yarmouthian was obsolete and it was several stages,

  • Like 3
Link to comment
Share on other sites

7 hours ago, Piney said:

I thought the concept of the Yarmouthian was obsolete and it was several stages,

I don't know about obsolete, but there were several stages.

Doug

  • Like 3
Link to comment
Share on other sites

In Missouri, one can see Cambrian marine sandstones and limestones lapping onto what were apparently the St Francois Islands, at that time.

  • Like 2
  • Thanks 1
Link to comment
Share on other sites

15 hours ago, Doc Socks Junior said:

In Missouri, one can see Cambrian marine sandstones and limestones lapping onto what were apparently the St Francois Islands, at that time.

I thought you were more igneous leaning.

  • Like 1
Link to comment
Share on other sites

6 hours ago, Piney said:

I thought you were more igneous leaning.

Correct as usual! I was primarily showing students the granites and tuffs which comprise up the mountains. Granites like the "Graniteville Granite" and the "Knoblick Granite", enjoyable names. But one has to try to be well-rounded. Besides, it's a pretty neat day when you can put your finger on a time gap of 900 million years.

 

  • Like 1
  • Thanks 2
Link to comment
Share on other sites

1 minute ago, Doc Socks Junior said:

Correct as usual! I was primarily showing students the granites and tuffs which comprise up the mountains. Granites like the "Graniteville Granite" and the "Knoblick Granite", enjoyable names. But one has to try to be well-rounded. Besides, it's a pretty neat day when you can put your finger on a time gap of 900 million years.

 

True and the St. Francois Mountains are older than the Appalachians and were from a time when the Earth's surface was nothing but pretty much islands. 

  • Like 2
Link to comment
Share on other sites

22 hours ago, Piney said:

True and the St. Francois Mountains are older than the Appalachians and were from a time when the Earth's surface was nothing but pretty much islands. 

Yes, way older! A billion years older!!

It's an interesting research area, honestly, as to how much landmass there was at that time. The 'craton' fragments make up ~15% of current landmass, but there's also certainly an amount of continental crust that go away down into the mantle. Also, of course, the St. Francois mountains are younger than "cratons", and in fact are pieces added onto the Laurentian core after United Plates of America times. Along with much of the middle core of our great country (much now covered with sedimentary crap and soul). 

  • Thanks 2
Link to comment
Share on other sites

15 minutes ago, Doc Socks Junior said:

Yes, way older! A billion years older!!

It's an interesting research area, honestly, as to how much landmass there was at that time. The 'craton' fragments make up ~15% of current landmass, but there's also certainly an amount of continental crust that go away down into the mantle. Also, of course, the St. Francois mountains are younger than "cratons", and in fact are pieces added onto the Laurentian core after United Plates of America times. Along with much of the middle core of our great country (much now covered with sedimentary crap and soul). 

The mountains are 1.5 billion years old to be exact.

And the Black Hills are around 1.7 or 8. 

Link to comment
Share on other sites

On 4/6/2024 at 4:12 AM, Piney said:

I thought the concept of the Yarmouthian was obsolete and it was several stages,

Now considered Pre-Illinoian Stage IIRC. 

cormac

  • Thanks 1
Link to comment
Share on other sites

 
2 minutes ago, cormac mac airt said:

Now considered Pre-Illinoian Stage IIRC. 

cormac

It's been for a while. The next interglacial stage after the Kansan glacial stage. Prior to the Illinoian. 

  • Thanks 2
Link to comment
Share on other sites

23 hours ago, Piney said:

The mountains are 1.5 billion years old to be exact.

And the Black Hills are around 1.7 or 8. 

Yep! The latter are what I'd consider 'cratonic' elements.

  • Like 2
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.