Is Earth expanding or shrinking?

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Every year, sediments build up that bury objects over time. Because of this, you would expect the Earth's diameter to gradually expand.

On the other hand, though, the sedimented layers get compressed over time as well, so this settling process should also cause the Earth to shrink.

Spreading ridges in the ocean and volcanoes are pushing up material from deeper underground, so that volume must be lost from the interior as it is moved to the surface.

So is it possible to conclude that Earth's surface layers are always moving deeper as new sedimentary layers get added above them; and that deeper material is being moved to the surface, so that the Earth is basically collapsing in on itself gradually as its interior is pushed up to become its exterior?

If so, we should consider that deeper layers of Earth were once on the surface and that they have been buried through time, as well as being pulled inward as deeper material makes its way up to the surface.

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@livinglava,

Can't you just google this yourself?

https://www.nasa.gov/topics/earth/features/earth20110816.html

1 Reply

@maxdancona,

maxdancona wrote:

Can't you just google this yourself?

https://www.nasa.gov/topics/earth/features/earth20110816.html

That's an interesting link, but it only addresses the net diameter change as remaining more-or-less stable. That seems fairly obvious.

What this thread is about:
1) expansion at the surface due to sedimentation of layer upon layer over time (e.g. grand canyon shows many layers representing long geological history)
2) shrinkage of layers deeper down as material is pushed up to the surface at spreading ridges and volcanic sites.

The expansion and shrinkage could cancel each other out to keep the net diameter stable, but outer layers would still be moving inward as newer layers stack up on top of them.

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@livinglava,

huh?

Isn't "expansion of the surface" and "diameter change" measuring the same thing?

1 Reply

@livinglava,

We will find out what it is doing when:

A) The planet explodes outwards

Or

B) Earth implodes, collapses inwards (and is then
dissolved within its molten core)

1 Reply

@maxdancona,

maxdancona wrote:

huh?

Isn't "expansion of the surface" and "diameter change" measuring the same thing?

Read my previous post. You intentionally misunderstand things I post to sow seeds of miscommunication.

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@Sturgis,

Sturgis wrote:

We will find out what it is doing when:

A) The planet explodes outwards

Or

B) Earth implodes, collapses inwards (and is then
dissolved within its molten core)

Are you being serious or sarcastic?

The point is that Earth may indeed be collapsing inward to the extent material is getting pushed up to the spreading ridges; only new material is piling up in layers at the surface to make up for the shrinkage.

In this way, sediments from the surface can gradually sink down as layers above them keep piling up.

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@livinglava,

Think about where all these sediments are actually produced. The vast mass of sediment that forms the layers of the sedimentary rocks were laid down uner water. Of course there are a few deposits that were not laid down in marin, setuarine, lacustrine, palludal, or some other water deposit . These would include minor amounts of ash deposits, wind driven silts called loess, sand dunes and the tail ends of glaciers and the melt water water drainage features beneath glaciers (stuff like eskers and kames etc). So, Very litle sedimentary deposits actually come from "dry land".On the contrary, dry land is
most commonly, an EROSION surface, where rains and wind carry the particles dowslope to larger and larger bodies of water that debouch into rivers, then estuaries and deltas and the cycle repeats itself.
Of course there are few variant styles of sedimentation like rivrs and lakes with no access to a main estuary, or actual inland seas, like the mediterranean used to be.1st and second year geology and soils and foundation engineering students learn these things so that they can identify all this in the field when they are setting up for foundations , mines or quarries.

1 Reply

https://en.wikipedia.org/wiki/Cosmic_dust

All this recycling is hearth-warming but it's still a very dirty place.

Look at all that 60 tons of interstellar dust falling on our home each year.

Time to clean out the closet.

1 Reply

@ekename,

I did a head estimate (with a helluva lotta rounding off), and Ive come up with a pound of space dust every 160 square miles .
So for govt worl its sorta between 1 pound of space dust every 100 to 175 square miles. You can take it to ounces per mi-sq, but its sorta looks like its about an ounce of **** every 10 square miles or 0.1 oz every square mile of earths area.
I dont think thatll even generate smog

2 Replies

@farmerman,

40,000 tons of space dust a year acktding to google. Sound about right farmerman?

1 Reply

@farmerman,

Yeah, the world is not only getting micrometerially fatter but also the heavy metal from live-in-lover's super nova blowing in rather than from the accretion disc at planetary formation is making us heavier.

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@RABEL222,

Hell I dont know how much spce dust we get per yer. I didnt check eke's number (Thats rule one I screwed up).

Lets just say its 60K T/yr, SOOO, that means Im off by a thousand times .Instead of 0.1 oz per square mile , we receive a bit less than 100 oz per square mile per year. This would be 0.15 oz per ACRE per yr.

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@farmerman,

farmerman wrote:

Think about where all these sediments are actually produced. The vast mass of sediment that forms the layers of the sedimentary rocks were laid down uner water.

You seem to be heading toward a point here; but what is it, exactly?

Quote:

Of course there are a few deposits that were not laid down in marin, setuarine, lacustrine, palludal, or some other water deposit . These would include minor amounts of ash deposits, wind driven silts called loess, sand dunes and the tail ends of glaciers and the melt water water drainage features beneath glaciers (stuff like eskers and kames etc).

Ok, here you toss around a lot of esoteric terminology to build up credibility without using the information to actually make a point.

Quote:

So, Very litle sedimentary deposits actually come from "dry land"

Ok, so now it seems you are making a point about the relative significance of 'dry land' vs. underwater land.

Quote:

.On the contrary, dry land is most commonly, an EROSION surface, where rains and wind carry the particles dowslope to larger and larger bodies of water that debouch into rivers, then estuaries and deltas and the cycle repeats itself.

I agree with you that runoff is moving sediments around, but others are being buried in place over time. There is a lot of organic material that gets more-or-less preserved underground.

Quote:

Of course there are few variant styles of sedimentation like rivrs and lakes with no access to a main estuary, or actual inland seas, like the mediterranean used to be.1st and second year geology and soils and foundation engineering students learn these things so that they can identify all this in the field when they are setting up for foundations , mines or quarries.

Look at the tar sands oil. That oil is forming from sedimentation of what? Inland sea bottom or land-based ecosystems? There are all these fossil fuel deposits all around, in various concentrations, and what is happening to all those energy-rich layers through time besides them getting buried ever deeper as other material rises up at the spreading ridges to make room for them to collapse further toward the core?

Granted at the surface there are plate tectonics and hydrological flow patterns that cause some stuff to remain at the surface while other parts get subducted or only gradually get buried deep enough to sink down below the crust-level, but if the core is pumping out material to the spreading ridges, then shouldn't the layers that are getting buried more and more deeply also be converging? I.e. as more outer layers shrink down to become more inner layers, their circumference has to shrink, so material would be getting pushed together laterally as they fall deeper down, no?

1 Reply

@livinglava,

Quote:

You seem to be heading toward a point here; but what is it, exactly?

WIthout sounding too elementary, I am saying that we dont see many actual stratigraphic layers in the Grand Canyon (your example) that ARE NOT water laid deposits. There are about 3 sand dune layers that, like the Mediterranean basin, were quickly DROWNED by incoming sediment laden runnoff water.

The rest of your response seems to just be your normal return to snotty retort and insult. So the rest of the readers know, I started my response to LL's question WITHOUT any comment. I mertried to answer him with some factual observations that he should consider in hi "breathing arth" wvidence.
Apparently he wishes to not learn a fuckin thing. He just wants to ridicule anything That, perhaps, he doesnt understand.

I think that, rather than talking down to people and having them insult me for "ridiculing their intelligence" I choose to talk AT the correspondent.
So I get criticized for being "Esoteric".

LL, unless you are 8 yrs old and unable to look up those perfectly good geologic and engineering terms, I think you just wish to be spoon fed and then you just want to whine about being insulted(not realizing that it was information directly relevant to your question).
\

I often teach groups of kids that have interests in dinosaurs and geology. I ve been surprised at how well they keep up and actually forge ahead just by being challenged with words that are technical in nature and, when consulted in an on-line encyclopedia or glossary, would exude great amounts of additional and real esoterica. (But the kids quickly picked it up).
And these werent all self proclaimed Ollie's , most were smart and smart enough to larn quickly but not all were gifted.

You seem to hve made a career of just sitting back and hoping everything would be pre chewed for your digestion.

I sorta wish you well, but I dont predict a lot of success in your pursuits. Im beginning to think your just lazy , but smart enough to know the secret of getting answers out of the internet.

1 Reply

@farmerman,

farmerman wrote:

WIthout sounding too elementary, I am saying that we dont see many actual stratigraphic layers in the Grand Canyon (your example) that ARE NOT water laid deposits. There are about 3 sand dune layers that, like the Mediterranean basin, were quickly DROWNED by incoming sediment laden runnoff water.

Don't worry about 'sounding elementary.' As Einstein said, "If you can't explain it simply, you don't understand it well enough."

I've heard that about the Grand Canyon layers being water-laid deposits, but I forgot whether it was from someone talking about Noah's flood or not, which you would disagree with. No matter, do you mean to say then that land doesn't build up in layers due to sediments everywhere? It has always been my understanding that things get buried deeper over time and that is why archaeologists have to dig for ancient relics.

It's also just logical that all the dropping and sediments, etc. from wind and living ecosystems pile up year after year and millennium upon millennium.

Quote:

The rest of your response seems to just be your normal return to snotty retort and insult. So the rest of the readers know, I started my response to LL's question WITHOUT any comment. I mertried to answer him with some factual observations that he should consider in hi "breathing arth" wvidence.
Apparently he wishes to not learn a fuckin thing. He just wants to ridicule anything That, perhaps, he doesnt understand.

Here you go back to provocations and fight-picking.

Quote:

I think that, rather than talking down to people and having them insult me for "ridiculing their intelligence" I choose to talk AT the correspondent.
So I get criticized for being "Esoteric".

'Esoteric' is a word with a meaning. I was just analyzing the function of how your previous post seemed to be constructed. There was a part where you included a slew of esoteric facts that didn't seem to be directly related to any point you were making, so it seemed like the point was just to build yourself up as a person who knows a lot of facts in order to be accepted as an authority rather than grounding your point in explanation.

People do what you do a lot. They don't really explain the points or claims they're making, but rather they build themselves up as an authority in order to insist that you accept their claims without them explaining them. If you just explain the reason you are claiming something, then your reasoning should stand on its own without you proving that you know a lot about the subject in general.

Quote:

LL, unless you are 8 yrs old and unable to look up those perfectly good geologic and engineering terms, I think you just wish to be spoon fed and then you just want to whine about being insulted(not realizing that it was information directly relevant to your question).

I do look things up when I can see that it is something that is part of understanding an explanation that's valid, or if I'm just personally interested. But you should realize that some people just post a lot of quasi-related terms and then it's not worth going on a wild-goose chase because they decided to spout a load of vocabulary that's only tangentially related to the issue in question.

Quote:

I often teach groups of kids that have interests in dinosaurs and geology. I ve been surprised at how well they keep up and actually forge ahead just by being challenged with words that are technical in nature and, when consulted in an on-line encyclopedia or glossary, would exude great amounts of additional and real esoterica. (But the kids quickly picked it up).
And these werent all self proclaimed Ollie's , most were smart and smart enough to larn quickly but not all were gifted.

You're talking about teaching kids/people just generally about a subject without addressing some specific point. If a kid asked you to explain the distributive property of multiplication and you started talking about the order of operations or other tangentially-related math terms, it wouldn't answer the kid's question and it would actually be a way of avoiding the question, while simultaneously blaming the kid for not being receptive to your teaching.

Quote:

You seem to hve made a career of just sitting back and hoping everything would be pre chewed for your digestion.

You just want to fight, accuse, witch-hunt, etc. It takes a lot of patience to deal with your posts to get to the parts where you actually respond to something in a scientific way.

Quote:

I sorta wish you well, but I dont predict a lot of success in your pursuits. Im beginning to think your just lazy , but smart enough to know the secret of getting answers out of the internet.

I don't think you could take half as much spit in the face as I take from people like you and maintain the patience to get any useful discussion out of them. I may be wrong, though. We'll never know because you have the privilege of sitting on a high horse of institutional legitimacy while I have to work as an amateur intellectual.

Sorry you have so much trouble with respect, though. It will cost you karma points in your next life or even before, maybe, you never know.

1 Reply

@livinglava,

ok, Im outta here.

1 Reply

@farmerman,

farmerman wrote:

ok, Im outta here.

As I said, you like to dish out the insults and negativity, but you don't like taking them.

Maybe if you just stuck to respectful discussion instead of talking down and demanding worship through it all, you would enjoy the same respect and nothing but respect in return.

1 Reply

@livinglava,

Actually my industry is based on heated arguments among colleagues. Some times these arguments can lead to personal relationship changes among former friends and colleagues. No, Im certainly not afraid of what you have to say , mostly because you deny so much that doesnt agree with your simple worldview and thats no different the world over.
Ive given you some ral world examples of honest science thinking and youre apparently incapable of even understanding the facts so that you could develop a counter argument. You just try to buffalo your way through easy concepts (by calling them esoteric).

Why not just bite the bullet an tell the world that you believe that the Noachian Flood is real "science"

2 Replies

@farmerman,

farmerman wrote:

Actually my industry is based on heated arguments among colleagues. Some times these arguments can lead to personal relationship changes among former friends and colleagues. No, Im certainly not afraid of what you have to say , mostly because you deny so much that doesnt agree with your simple worldview and thats no different the world over.
Ive given you some ral world examples of honest science thinking and youre apparently incapable of even understanding the facts so that you could develop a counter argument. You just try to buffalo your way through easy concepts (by calling them esoteric).

When I told you that you were posting esoteric information without explaining it, it was to point out how your argumentation is ultimately empty rhetoric and not grounded in explicated reasoning.

If I say that 8x8=64 to an elementary schooler and instead of explaining how to multiply 8x8 I rattle of a bunch of other times tables to show that I know what 3x2 and 5x7 and 9x8 and 7x6 all equal, then I'm not really explaining how/why 8x8=64 but rather just trying to convince the kid to accept what I'm telling him/her because I know a lot of multiplication facts.

I hope you can see how a preponderance of esoteric facts without explanation is a bad substitute for explaining why/how something is actually true.

Quote:

Why not just bite the bullet an tell the world that you believe that the Noachian Flood is real "science"

Personally, I think the Flood of Noah story is a generalized story that represents a lot of other stories in a superlative way. So I think there were lots of farmers who saved their families and livestock by building some kind of boat or other high water mitigation to weather a flood; but the story of Noah sums all those other stories up as the superlative story of an ultimate flood that drowns the entire world except the people and animals in the ark, and the important part is giving meaning to the elements of the story.

Theology is about explaining life experiences in terms of divinity.

That said, I cannot prove anyone wrong who believe the Flood of Noah was an actual historical event, and so I listen to people who explain their theories with an open-critical mind; i.e. I accept them tentatively without assuming there's no possibility they won't be proven false in some way at some point.

That doesn't make me agnostic, because I do believe in God and Truth and reality; but I know the theological value of the story of Noah's Flood in the Bible is not dependent on whether it was a single definite historical event or a composite story that combines truth-revelations from many different flood experiences and transmits them in a superlative story of an ultimate flood sent by God Almighty for the reasons explained in the Bible.

Anyway, you're changing the purpose of this thread by going on about other topics besides the expanding/shrinking Earth. What I'm really interested in discussing is how the deepening layers concentrate material as they move closer to the core. At the crust, there are obviously all the complexities of subduction and plates floating on top of the subducting material, but I assume that as you go deeper, the rising temperatures and pressures soften things up to where they can consolidate/compress as they fall deeper and deeper. Do you think there are reasons they wouldn't, such as the way the plates at the surface remain solid and resist collapsing into the subduction zone together with the subducting plate?

1 Reply

Is Earth expanding or shrinking?

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