Erakivnor wrote:

Here you missed the point again. The point was that the whole column comprising the folded and stacked eroded old rock of the craton underlaying flat sedimentary strata can be uplifted as a whole without further folding.

documentation about uplift of cratons?

I mentioned the Colorado Plateau (Karlstrom et al 2012 Lithosphere 8, p835).

Erakivnor wrote:
Evidences I brought state that they are in equilibrium since a long time and actually what we see (including their igneous parts) are basically denudation of higher altitudes without uplift (well in that sense you have uplift when you unload the cratonic shelf, but no mass addition is required).

Most cratons are in isostatic equilibrium but why do you talk about these ones? The discussion was about uplifted cratons, not cratons in equilibrium.
And could you detail what you mean by mass addition inside a craton? Do you refer to plutonism?

Erakivnor wrote:
About the russian literature @[color=#CC0000][b]Florian[/b][/color] mentioned: I have two serious problems on that literature.
1) Their overinterpretation of data (e.g. calculating moment tensors with different equations than the Harvard CMT, they state they can calculate moment tensors of EQ with magnitude about 1, usually impossible or not reliable in much more dense networks and things like that).

In which paper? They mostly discuss the P and T axis (for example in Lukk & Shevchenko 2008 IPSE 44 p85).

Erakivnor wrote:
2) conclusions about seismicity "unrelated" to tectonics in the areas they study. For example vertical earthquake arrays they study are not that vertical, and not unreasonable for the seismotectonics of e.g. Himalayan belts.

The earthquakes under Kazakhstan are clearly organized in pillar structures (see HERE).

Erakivnor wrote:
3) Even assuming that the seismicity they observe is unrelated to tectonic structure, and even assuming that is caused by fluid migration....it has yet to be proved that they are mass addition and not simpli migration of such a fluids!

Don't you consider that fluids migrating into a layer add mass to that layer?

Erakivnor wrote:More on Orogenesis:

Let's start from the geometry, which is the basic starting point in almost every geological observation:
1)Orogens are usually belts (both ancient and both modern examples). I.e. linear features difficult to explain with diapirism.

Mobile belts are usually arcuate. These belts form at the compressional perimeter of a zone in expansion, typically the case in the western Mediterranean basin. In this case the cause of the expansion is diapirism.

Erakivnor wrote:
2)Thrusts (i.e. compressional faults) usually predates, and are cut by normal faults involved in Altipiano formations (i.e. contrary to the EE view of Ollier where a "plain" is dissected by various degrees ad uplifted and THEN it gravitationally spreads in thrusts).

I'm not sure of your "THEN". Ollier claims that the uplift causes the thrusting of nappes, but he does not claim that thrusting happens after the uplift.

Erakivnor wrote:
3)Moreover thrusts displacements (fault slip) are usually much bigger than Normal fault displacements.

It does not seem in contradiction with a zone in expansion being at the origin of thrusting.

Erakivnor wrote:
4) Terranes stacking of complex belts juxtapose lands of different ages (i.e. appalachians, urals, Himalaya itself, the verkhoyansk ridge etc etc) and including suture zones (ophiolites). This strongly points out against orogenesis as a precursor to oceanic expansion (in a WPacific EE style). Otherwise "diapiric" orogenesis would split terranes of same ages (actually the same terrane) as it occurs in actual rifts like Ethiopia, Bajickal, Basin and Range province.

First, doming (thus uplift) accompanies rifting.
Second, stacking of terranes with suture results from the stacking of different mobile belts, themselves resulting from different mantle currents. Mantle currents are observed in WPacific.
Third, I guess you understand now that there are different causes of orogenesis: orogenic waves around spreading diapirs, deep fluids migrating toward the surface and metasomatizing the layers found on their migration path, inducing swelling...

My bold added

Florian wrote:Most cratons are in isostatic equilibrium but why do you talk about these ones? The discussion was about uplifted cratons, not cratons in equilibrium.

this is exactly the point: cratons are not in disequilibrium anymore. they are exposed roots of previous unstable regions. All cratons are uplifted (because longly eroded and thus mainly "flat") but not presently uplifting. From this arise the fact that Ollier & company observe folded rocks and structural stacking without topographical uplift.

Erakivnor wrote:
About the russian literature @[color=#CC0000][b][color=#CC0000][b]Florian[/b][/color][/b][/color] mentioned: I have two serious problems on that literature.
1) Their overinterpretation of data (e.g. calculating moment tensors with different equations than the Harvard CMT, they state they can calculate moment tensors of EQ with magnitude about 1, usually impossible or not reliable in much more dense networks and things like that).

In which paper? They mostly discuss the P and T axis (for example in Lukk & Shevchenko 2008 IPSE 44 p85).
PT axis are difficult to determine for weak earthquakes, and moment tensors are built on those axis. I was more specifically referring to their 2010 paper (DOI: 10.1134/S1069351311030050)

Erakivnor wrote:
2) conclusions about seismicity "unrelated" to tectonics in the areas they study. For example vertical earthquake arrays they study are not that vertical, and not unreasonable for the seismotectonics of e.g. Himalayan belts.

The earthquakes under Kazakhstan are clearly organized in pillar structures (see HERE).
this doesn't mean that they are unrelated to tectonic structure. This is an additional and not supported inference

Erakivnor wrote:
3) Even assuming that the seismicity they observe is unrelated to tectonic structure, and even assuming that is caused by fluid migration....it has yet to be proved that they are mass addition and not simpli migration of such a fluids!

Don't you consider that fluids migrating into a layer add mass to that layer?

Yes it is an addition to the layer (in he case fluids stop their migration there) but from this fact is hard to jump to the conclusion that this mass increases the earth's mass. Ultimately all the crust differentiated and accreted from the mantle, then I can't see the problem if it continues to do so.

Florian wrote:
Mobile belts are usually arcuate. These belts form at the compressional perimeter of a zone in expansion, typically the case in the western Mediterranean basin. In this case the cause of the expansion is diapirism.
Belts are arcuate but linear and not spreading from the center. belts like those in the Mediterranean do not belong to same periods of tectonic activity (they are only spatially juxtaposed).

Erakivnor wrote:
2)Thrusts (i.e. compressional faults) usually predates, and are cut by normal faults involved in Altipiano formations (i.e. contrary to the EE view of Ollier where a "plain" is dissected by various degrees ad uplifted and THEN it gravitationally spreads in thrusts).

I'm not sure of your "THEN". Ollier claims that the uplift causes the thrusting of nappes, but he does not claim that thrusting happens after the uplift.
read again your statement. A gravitational spreading as in EE orogenesis mechanism implies a topographical relief in order to occur. If uplift does not predates thrusting this occurrence is disproved.

Erakivnor wrote:
3)Moreover thrusts displacements (fault slip) are usually much bigger than Normal fault displacements.

It does not seem in contradiction with a zone in expansion being at the origin of thrusting.
That means that the tectonic importance of thrusts is overwhelming in orogens. Expanding structures as real rifts have dominant normal faulting. (and their uplift does not generate orogen-scale thrusting due to gravitational gliding)

Erakivnor wrote:
4) Terranes stacking of complex belts juxtapose lands of different ages (i.e. appalachians, urals, Himalaya itself, the verkhoyansk ridge etc etc) and including suture zones (ophiolites). This strongly points out against orogenesis as a precursor to oceanic expansion (in a WPacific EE style). Otherwise "diapiric" orogenesis would split terranes of same ages (actually the same terrane) as it occurs in actual rifts like Ethiopia, Bajickal, Basin and Range province.

First, doming (thus uplift) accompanies rifting.
Second, stacking of terranes with suture results from the stacking of different mobile belts, themselves resulting from different mantle currents. Mantle currents are observed in WPacific.
Third, I guess you understand now that there are different causes of orogenesis: orogenic waves around spreading diapirs, deep fluids migrating toward the surface and metasomatizing the layers found on their migration path, inducing swelling...
Before stacking different mobile belts (which can be driven by mantle currents but also by other things, at least in Plate Tectonics) any single belt must form and according to EE must split a single terrane. This is clearly disproved by any continental geological map.

Geometry simply points out that "diapirism" cannot be a main cause of uplift and orogenesis. Even if it would be (and it is NOT), jumping from the occurrence of diapirism to mass-addition-to-the-Earth is a completely rootless statement.

Please use properly the quote function and do not use bold. It is realy hard to follow the exchange if you do not respect quoting.

Erakivnor wrote:

Florian wrote:Most cratons are in isostatic equilibrium but why do you talk about these ones? The discussion was about uplifted cratons, not cratons in equilibrium.

this is exactly the point: cratons are not in disequilibrium anymore. they are exposed roots of previous unstable regions. All cratons are uplifted (because longly eroded and thus mainly "flat") but not presently uplifting. From this arise the fact that Ollier & company observe folded rocks and structural stacking without topographical uplift.

I re-read Ollier's book, and nowhere he claimed that "all cratons are presently uplifting". You misrepresent Ollier's position.
Ollier simply remind us that if we observe folding in an orogen, it does not imply that this folding is comtemporaneous of the latest orogenetic activity. I think it is rather obvious.

Erakivnor wrote:

Florian wrote:
In which paper? They mostly discuss the P and T axis (for example in Lukk & Shevchenko 2008 IPSE 44 p85).

PT axis are difficult to determine for weak earthquakes, and moment tensors are built on those axis. I was more specifically referring to their 2010 paper (DOI: 10.1134/S1069351311030050)

Looking at Figure 4 of this paper, they had largely enough data to constrain the P/T axis.

Erakivnor wrote:

Florian wrote:The earthquakes under Tadjikistan are clearly organized in pillar structures (see HERE).

this doesn't mean that they are unrelated to tectonic structure. This is an additional and not supported inference

Shevchenko et al 2010 present arguments that this particular pillar-like structure under Tadjikistan has no correlation with tectonic structures of the region.
On a sidenote, it would be interesting to verify if this structure is connected to the two fluid-enriched channels running in the lower crust of the Tibetan Plateau.

Erakivnor wrote:

Florian wrote:
Don't you consider that fluids migrating into a layer add mass to that layer?

Yes it is an addition to the layer (in he case fluids stop their migration there) but from this fact is hard to jump to the conclusion that this mass increases the earth's mass. Ultimately all the crust differentiated and accreted from the mantle, then I can't see the problem if it continues to do so.

Nobody jump to the conclusion that this mass increases the earth's mass!
The point is that plate tectonics present orogenesis, belt formation as the result of plate convergence with plate surface reduction. But evidence support that orogenesis is resulting from crust enrichement by deep fluids (leading to swelling and thrusting) or sublithospheric mantle flow, none of these mechanisms resulting in net surface reduction. This is the absence of significant surface reduction, that implies a large surface increase of earth, a large increase in volume, and thus a large increase in mass.

Erakivnor wrote:

Florian wrote:
Mobile belts are usually arcuate. These belts form at the compressional perimeter of a zone in expansion, typically the case in the western Mediterranean basin. In this case the cause of the expansion is diapirism.

Belts are arcuate but linear and not spreading from the center. belts like those in the Mediterranean do not belong to same periods of tectonic activity (they are only spatially juxtaposed).

The belts are arcuate and linear because they form at the margin of the expanding diapir, not above it (!).
The belts do not belong to same periods because they do not result from the same diapiric activity.

Erakivnor wrote:

Florian wrote:
I'm not sure of your "THEN". Ollier claims that the uplift causes the thrusting of nappes, but he does not claim that thrusting happens after the uplift.

read again your statement. A gravitational spreading as in EE orogenesis mechanism implies a topographical relief in order to occur. If uplift does not predates thrusting this occurrence is disproved.

EE orogenesis is not limited to gravitational spreading, and uplift does not have to predate thrusting as it can be contemporaneous.

Erakivnor wrote:

Florian wrote:
It does not seem in contradiction with a zone in expansion being at the origin of thrusting.

That means that the tectonic importance of thrusts is overwhelming in orogens. Expanding structures as real rifts have dominant normal faulting. (and their uplift does not generate orogen-scale thrusting due to gravitational gliding)

We have a terminology issue here. A rift is not an "expanding structure" in the sense I use it: there is a net influx of material inducing the expansion of the structure.
A rift is a "tensional structure": the surface tension induces lithosphere thining, which is accompanied by an isostatic compensation translating into asthenospheric upwelling.

Erakivnor wrote:

Florian wrote:
First, doming (thus uplift) accompanies rifting.
Second, stacking of terranes with suture results from the stacking of different mobile belts, themselves resulting from different mantle currents. Mantle currents are observed in WPacific.
Third, I guess you understand now that there are different causes of orogenesis: orogenic waves around spreading diapirs, deep fluids migrating toward the surface and metasomatizing the layers found on their migration path, inducing swelling...

Before stacking different mobile belts (which can be driven by mantle currents but also by other things, at least in Plate Tectonics) any single belt must form and according to EE must split a single terrane. This is clearly disproved by any continental geological map.

Your hypothesis in italic is wrong. A mobile belt with back-arc is formed at the front of a mantle current (or at the margin of an expanding mantle structure, see W-Med basin): it does not have to split a single terrane, but just plow thru whatever is on its path.

Erakivnor wrote:
Geometry simply points out that "diapirism" cannot be a main cause of uplift and orogenesis.

The fact is that diapirism is not the sole cause of uplift and orogenesis in auxotectonics. Uplift and orogenesis are related to expanding mantle and lithospheric structures.

Erakivnor wrote:Even if it would be (and it is NOT), jumping from the occurrence of diapirism to mass-addition-to-the-Earth is a completely rootless statement.

As rootless as your accusation.

OT

Florian wrote:Please use properly the quote function and do not use bold. It is realy hard to follow the exchange if you do not respect quoting.

I try to avoid quoting because I think that, in this very long discussions, is very hard to follow and the reader loses focus quickly.
Nevertheless I can't see how difficult is to check the bold. It would be helpful to summarize the discussion sometimes.
EOT

Florian wrote:

Erakivnor wrote:
Cratons are not in disequilibrium anymore. they are exposed roots of previous unstable regions. All cratons are uplifted (because longly eroded and thus mainly "flat") but not presently uplifting. From this arise the fact that Ollier & company observe folded rocks and structural stacking without topographical uplift.

I re-read Ollier's book, and nowhere he claimed that "all cratons are presently uplifting". You misrepresent Ollier's position.
Ollier simply remind us that if we observe folding in an orogen, it does not imply that this folding is comtemporaneous of the latest orogenetic activity. I think it is rather obvious.

I'm not misinterpreting. Neither Ollier or me said that cratons are presently uplifting. I only said that they did it in the past. The obvious statement you mentioned has never been questioned by me.
What is true though is that folding and topographical uplift are proven by geological means to be contemporaneous both for ancient orogens (e.g. the well studied cases of verkhoyansk and appalachians) and modern ones.

Florian wrote:

Erakivnor wrote:

Florian wrote:
In which paper? They mostly discuss the P and T axis (for example in Lukk & Shevchenko 2008 IPSE 44 p85).

PT axis are difficult to determine for weak earthquakes, and moment tensors are built on those axis. I was more specifically referring to their 2010 paper (DOI: 10.1134/S1069351311030050)

Looking at Figure 4 of this paper, they had largely enough data to constrain the P/T axis.

the points in that tensor solutions ARE the PT axis, not data to determine them. and are exactly those point which are highly questioned. But I am not a true seismologist for the sake of truth.

Florian wrote:

Nobody jump to the conclusion that this mass increases the earth's mass!
The point is that plate tectonics present orogenesis, belt formation as the result of plate convergence with plate surface reduction. But evidence support that orogenesis is resulting from crust enrichement by deep fluids (leading to swelling and thrusting) or sublithospheric mantle flow, none of these mechanisms resulting in net surface reduction. This is the absence of significant surface reduction, that implies a large surface increase of earth, a large increase in volume, and thus a large increase in mass.

1)Crust enrichment by deep fluid has to be proved by other than seismological means and the mass balance of such fluids should be really high to account for what you say...unfortunately such a kind of proof is lacking.
2)Net surface reduction is OBSERVED due to the thrusting itself. Nappe and windows are words well known by geologists indicating exactly that.

Florian wrote:
The belts are arcuate and linear because they form at the margin of the expanding diapir, not above it (!).
The belts do not belong to same periods because they do not result from the same diapiric activity.
This is speculation, not a geometrical datum. The geometrical datum is that belts are linear respect to what is expected to occur at the MARGINS of a diapir. The arcuate shapes you point to are diacronous.

Florian wrote:
EE orogenesis is not limited to gravitational spreading, and uplift does not have to predate thrusting as it can be contemporaneous.

If EE mechanism is "the mantle diapir" and gravitational spreading is that commonly invoked...then uplift has to predate thrusting (ant it does not). Gravitational spreading can be contemporaneous only if enough uplift is accumulated before.

Florian wrote:
We have a terminology issue here. A rift is not an "expanding structure" in the sense I use it: there is a net influx of material inducing the expansion of the structure.
A rift is a "tensional structure": the surface tension induces lithosphere thining, which is accompanied by an isostatic compensation translating into asthenospheric upwelling.

I honestly can't read your mind. When I write "rift" I think to rifts as usually cited in geological literature. In the case of Rifts described in PT they share very different geometrical and geophysical signatures than orogens, trenches, backarcs to which they are associated in EE "literature".

Florian wrote:
Your hypothesis in italic is wrong. A mobile belt with back-arc is formed at the front of a mantle current (or at the margin of an expanding mantle structure, see W-Med basin): it does not have to split a single terrane, but just plow thru whatever is on its path.

I'm not talking about belts stacking. I'm talking about belt initiation.

Florian wrote:

Erakivnor wrote:
Geometry simply points out that "diapirism" cannot be a main cause of uplift and orogenesis.

The fact is that diapirism is not the sole cause of uplift and orogenesis in auxotectonics. Uplift and orogenesis are related to expanding mantle and lithospheric structures.

You should try to prove your statement from the data point of view. not the reverse.

Florian wrote:

Erakivnor wrote:Even if it would be (and it is NOT), jumping from the occurrence of diapirism to mass-addition-to-the-Earth is a completely rootless statement.

As rootless as your accusation.

Starting from the point that I am not accusing anyone/thing...what I say is perfectly logical, and I simply brought geometrical/kinematics observations. Keep focus on data, don't bring it to the "trial" discussion.

Erakivnor wrote:
I try to avoid quoting because I think that, in this very long discussions, is very hard to follow and the reader loses focus quickly.
Nevertheless I can't see how difficult is to check the bold. It would be helpful to summarize the discussion sometimes.

You don't have to quote multiple quote levels. Just quote the last level to avoid long posts. The quote function is implemented to allow the reader to easily go back to the previous messages if necessary (by clicking on "wrote").
And be careful with the quote levels. You mixed them again.

Erakivnor wrote:
I'm not misinterpreting. Neither Ollier or me said that cratons are presently uplifting. I only said that they did it in the past.

Who's "they" if not Ollier?

Erakivnor wrote:
The obvious statement you mentioned has never been questioned by me.
What is true though is that folding and topographical uplift are proven by geological means to be contemporaneous both for ancient orogens (e.g. the well studied cases of verkhoyansk and appalachians) and modern ones.

Sure, during orogenesis there is uplift and folding. We can certainly agree on that. But I fail to see why you believe it does not fit in the expanding earth theory.

Erakivnor wrote:
the points in that tensor solutions ARE the PT axis, not data to determine them. and are exactly those point which are highly questioned. But I am not a true seismologist for the sake of truth.

Not at all! The dots are the first motion of the seismic P-wave! Each dot corresponds to one recording. The first motions are distributed on the "beach ball" and their distribution allow to build the focal mechanism solution which gives the P and T axis (45° with the focal planes).
That wikipedia page is not too bad for a quick reminder: http://en.wikipedia.org/wiki/Focal_mechanism

One more time, they got a lot of recordings to constrain the P/T axis.

Erakivnor wrote:1)Crust enrichment by deep fluid has to be proved by other than seismological means and the mass balance of such fluids should be really high to account for what you say...unfortunately such a kind of proof is lacking.

Here you suggest that the crust enrichment thing entirely relies on seismological means. This is false. The set of evidence presented by Prilepin and Shevchenko are also based on geodynamics, structural geology, geodesy etc (see Prilepin & Shevchenko Geodynamics of the Mediterranean Region from GPS Data, 2005, Geotectonics 39, p19-31)
In anyway, the seismological evidence of crustal expansion presented by Shevchenko et al are strong. You can't dismiss them so easily.

Erakivnor wrote:
2)Net surface reduction is OBSERVED due to the thrusting itself. Nappe and windows are words well known by geologists indicating exactly that.

This is factually incorrect. Thrusting induced by an expanding crustal structure does not lead to a net surface reduction.
That is, at a different scale, like water freezing in a rock crevice. The expansion of water induces an outward pressure which leads to the equivalent of reverse faulting in the rock without any net surface reduction of the rock.

Erakivnor wrote:
This is speculation, not a geometrical datum. The geometrical datum is that belts are linear respect to what is expected to occur at the MARGINS of a diapir. The arcuate shapes you point to are diacronous.

what is expected to occur at the margins of an expanding diapir? an expanding diapir generates outward pressure. This outward pressure contributes to the formation of the belt. The geometry of the belt will depend on the geometry of the diapir and its direction of expansion. Look again at the mediterranean basins as example of expanding diapirs:

The dash lines represents the past position of the belts. The belts moved as the diapirs expanded.

Erakivnor wrote:If EE mechanism is "the mantle diapir" and gravitational spreading is that commonly invoked...then uplift has to predate thrusting (ant it does not).

Your hypothesis in italic is reductive and therefore incorrect.

Erakivnor wrote:Gravitational spreading can be contemporaneous only if enough uplift is accumulated before.

You seem to have a clear idea of the amount of uplift necessary for the formation of a nappe. This would also depend on the nature of the décollement surface. I'm genuilely interested by your numbers and the method of calculation.

Erakivnor wrote:I honestly can't read your mind. When I write "rift" I think to rifts as usually cited in geological literature. In the case of Rifts described in PT they share very different geometrical and geophysical signatures than orogens, trenches, backarcs to which they are associated in EE "literature".

Yes, rifts (and MORs) are often associated to orogens by expansionists, and this is an error. This one is clearly on Carey.
Though, MORs and Back-arc ridges are not different.

I make a clear distinction between an orogen and a ridge.
An orogen is an expanding structure because it is enriched in light, volatile-rich, fluidic material coming from the mantle (eventually deep) and finding its way into the crust. The enrichment leads to expansion of the crust and outward pressure.

A rift is a tensional structure, but not an expanding structure, because it is not enriched by the same light material percolating in an orogen. The surface tension at the origin of the rift results from the emplacement of dense material at depth, not at the surface: the emplacement of deep layers induces tension in the upper layers. The formation of melts erupting at a ridge is a direct consequence of that tension (crustal thinning -> isostatic compensation -> local upwelling of mantle -> decompression melting). But this is the upper mantle just below the ridge that is melting, not material rising from deeper mantle layers.

These are fundamental notions necessary to understand tectonics of the expanding earth.

Erakivnor wrote:

Florian wrote:

Erakivnor wrote:Even if it would be (and it is NOT), jumping from the occurrence of diapirism to mass-addition-to-the-Earth is a completely rootless statement.

As rootless as your accusation.

Starting from the point that I am not accusing anyone/thing...

Excuse me, but you clearly accused someone of "jumping from the occurrence of diapirism to mass-addition-to-the-Earth" as shown by the quote above. And this accusation is rootless.

Erakivnor wrote:
what I say is perfectly logical, and I simply brought geometrical/kinematics observations. Keep focus on data, don't bring it to the "trial" discussion.

What you said so far is based on a lot of misunderstandings. But I don't blame you, it is not easy for someone not very familiar with the theory and the last developments. But I'm here to hopefully help you sort things out.

Florian wrote:

Erakivnor wrote:
I'm not misinterpreting. Neither Ollier or me said that cratons are presently uplifting. I only said that they did it in the past.

Who's "they" if not Ollier?

"They" are the cratons. They do not experience uplift now. But they did before reaching the equilibrium. We observe folded rocks in flat cratonic surfaces not because folding did not generate orogenesis, but because of long time erosion flattened it out.

Florian wrote:
Sure, during orogenesis there is uplift and folding. We can certainly agree on that. But I fail to see why you believe it does not fit in the expanding earth theory.

I was addressing the thesis of Ollier's in which folding and uplift (orogenesis) are not closely related. This only because in EE there is the need to prove Orogenesis as an extensional phenomenon. Geometry, the observations I posted a page ago, point against that. Compressive features are overwhelming. Even intrusive bodies show syinkinematic emplacement as compressive wedges, from Apennines, to Alps to Hymalaya to the Andes.

Florian wrote:

Erakivnor wrote:
the points in that tensor solutions ARE the PT axis, not data to determine them. and are exactly those point which are highly questioned. But I am not a true seismologist for the sake of truth.

Not at all! The dots are the first motion of the seismic P-wave! Each dot corresponds to one recording. The first motions are distributed on the "beach ball" and their distribution allow to build the focal mechanism solution which gives the P and T axis (45° with the focal planes).
That wikipedia page is not too bad for a quick reminder: http://en.wikipedia.org/wiki/Focal_mechanism
One more time, they got a lot of recordings to constrain the P/T axis.

What I am questioning are exactly the dots. I don't think they can constrain first motion (either P or T points), not for M1 earthquakes at tens of km depth. Moreover if you look carefully at the dots they present they are all mixed and not very easy to distinguish between P and T signals.

Florian wrote:

Erakivnor wrote:1)Crust enrichment by deep fluid has to be proved by other than seismological means and the mass balance of such fluids should be really high to account for what you say...unfortunately such a kind of proof is lacking.

Here you suggest that the crust enrichment thing entirely relies on seismological means. This is false. The set of evidence presented by Prilepin and Shevchenko are also based on geodynamics, structural geology, geodesy etc (see Prilepin & Shevchenko Geodynamics of the Mediterranean Region from GPS Data, 2005, Geotectonics 39, p19-31)

Not really strong...none of the presented data can lead to a mass balance of significant crustal imput.

Florian wrote:
In anyway, the seismological evidence of crustal expansion presented by Shevchenko et al are strong. You can't dismiss them so easily.

Not really. Their data are very controversial (see above) and also solutions they present show compression overall the "diapir" structure.

Florian wrote:

Erakivnor wrote:
2)Net surface reduction is OBSERVED due to the thrusting itself. Nappe and windows are words well known by geologists indicating exactly that.

This is factually incorrect. Thrusting induced by an expanding crustal structure does not lead to a net surface reduction.
That is, at a different scale, like water freezing in a rock crevice. The expansion of water induces an outward pressure which leads to the equivalent of reverse faulting in the rock without any net surface reduction of the rock.

Surface geology clearly disprove what you are saying: avery single orogen shows compressional features that account for shortenings up to one/two orders of magnitude of extensional features (i.e. normal faults). For example look at the Hymalaya and the tibetan plateaux. Or the Andes and the Altipiano (where it is present).

Florian wrote:

Erakivnor wrote:Gravitational spreading can be contemporaneous only if enough uplift is accumulated before.

You seem to have a clear idea of the amount of uplift necessary for the formation of a nappe. This would also depend on the nature of the décollement surface. I'm genuilely interested by your numbers and the method of calculation.

Gravitational push is induced by differential stress due to different topographic heights and/or lateral density contrast.
It can be demonstrated that lateral differential stress (gravitational push) is equal to: 1/2*g*h*D(1-D/d) where g is the acceleration, h is the height of the considered column, D is the density of the considered column and D/d is the density contrast.
For the contrast with air a simplification would be to assume non-balanced lithostatic pressure. Therefore the pressure can easily calculated as the lithostatic pressure itself.
Another way to calculate is to set a gravity "anomaly" equal to the height of the considered topography and calculate the difference in potential between mean regional geoid and the anomaly (being the potential the work required to move a mass from one point to another of the field you substitute the mass of your topography and get the work).
Stresses generated for example between an "oceanic" crust and "continental" crust 35km thick yield values of about 50-100 MPa.
For a vertical column of granite 8km tall the stress would be about 212 MPa (in contrast to air). 212 MPa is enough to fault rocks (in brittle condition they can yield 100-180 MPa as a rough approximation).
To make a clearer example without calculations: The african rift.it is uplifted by about 2000m respect to the surrounding plains of the continent (the former Pan-african orogens n.d.r.) and doesn't thrust away. With a topographical gradient not even the tibetan Plateau can thrust away with its present elevation (but it has been shown that it collapsed to the present position instead).

Florian wrote:
I make a clear distinction between an orogen and a ridge.
An orogen is an expanding structure because it is enriched in light, volatile-rich, fluidic material coming from the mantle (eventually deep) and finding its way into the crust. The enrichment leads to expansion of the crust and outward pressure.
A rift is a tensional structure, but not an expanding structure, because it is not enriched by the same light material percolating in an orogen. The surface tension at the origin of the rift results from the emplacement of dense material at depth, not at the surface: the emplacement of deep layers induces tension in the upper layers. The formation of melts erupting at a ridge is a direct consequence of that tension (crustal thinning -> isostatic compensation -> local upwelling of mantle -> decompression melting). But this is the upper mantle just below the ridge that is melting, not material rising from deeper mantle layers.
These are fundamental notions necessary to understand tectonics of the expanding earth.

Actually geophysical and geological evidences points into the opposite direction about what you say about rifts (magma sources, normal faults that lead to "expansion" etc. etc.) but I'm more interested in one thing: why expansion should work differently form one part to the other?

Florian wrote:
Excuse me, but you clearly accused someone of "jumping from the occurrence of diapirism to mass-addition-to-the-Earth" as shown by the quote above. And this accusation is rootless.

That's not an accusation, is simply remarking inconsistency between data and conclusions. Then if you want to take that as an accusation...well I don't care

Florian wrote:
What you said so far is based on a lot of misunderstandings. But I don't blame you, it is not easy for someone not very familiar with the theory and the last developments. But I'm here to hopefully help you sort things out.

Except that is difficult to see misunderstandings in evidences like thrust diplacements, shape of orogens, uplift/folding/faulting time and space relationships et cetera...why don't you then present the EE theory of orogenesis as you think about that? I tried to make a summary of what I've read and what you wrote but probably YOUR summary would be more compelling no? And then we can start to discuss from that post.

A couple of questions editing the figure you posted:

How many diapirs are there? How can they spread pressure if they are lower than the margins they are "overthrusting"? How do they exert horizontal pressure?

Also, if you take the segments in chronological order (not the stacked sequence of the image) they are clearly linear. From a diapir I would expect more curved thrusting, as it occurs in some way in the Hawaii

cut to the chase.....

http://en.wikipedia.org/wiki/Expanding_Earth

Paul Dirac suggested in 1938 that the universal gravitational constant had decreased in the billions of years of its existence. This led German physicist Pascual Jordan to a modification of general relativity and to propose in 1964 that all planets slowly expand. Contrary to most of the other explanations this one was at least within the framework of physics considered as a viable hypothesis. [12]
Measurements of a possible variation of the gravitational constant showed an upper limit for a relative change of 5•10−12 per year, excluding Jordan's idea.[13]
[edit]Scientific consensus

The theory had never developed a plausible and verifiable mechanism of action, but neither had any of its competing theories.[1] By the late 1970s the theory of plate tectonics made all other theories obsolete following the discovery of subduction, which was found to be an important part of a mechanism of action.[1]
Generally, the scientific community finds that there is no evidence in support of the Expanding Earth theory, and there is evidence against it:
Measurements with modern high-precision geodetic techniques show that the Earth is not currently increasing in size to within a measurement accuracy of 0.2 mm per year.[14] The lead author of the study stated "Our study provides an independent confirmation that the solid Earth is not getting larger at present, within current measurement uncertainties".[15] The motions of tectonic plates and subduction zones measured by a large range of geological, geodetic and geophysical techniques supports plate tectonics.[16][17][18]

Mass accretion on a scale required to change the Earth's radius is contradicted by the current accretion rate of the Earth, and by the Earth's average internal temperature: any accretion releases a lot of energy, which would warm the planet's interior.

Expanding Earth models based on thermal expansion contradict most modern principles from rheology, and fail to provide an acceptable explanation for the proposed melting and phase transitions.

Paleomagnetic data has been used to calculate that the radius of the Earth 400 million years ago was 102 ± 2.8% of today's radius.[19][20]
Examinations of data from the Paleozoic and Earth's moment of inertia suggest that there has been no significant change of earth's radius in the last 620 million years.[21]

fucking unreal what supposedly sensible people will waste their time on ....

Erakivnor wrote:"They" are the cratons. They do not experience uplift now. But they did before reaching the equilibrium. We observe folded rocks in flat cratonic surfaces not because folding did not generate orogenesis, but because of long time erosion flattened it out.

[...]

I was addressing the thesis of Ollier's in which folding and uplift (orogenesis) are not closely related. This only because in EE there is the need to prove Orogenesis as an extensional phenomenon. Geometry, the observations I posted a page ago, point against that. Compressive features are overwhelming. Even intrusive bodies show syinkinematic emplacement as compressive wedges, from Apennines, to Alps to Hymalaya to the Andes.

Now I understand what's bothering you. You think that orogenesis is an extensional phenomenon in EE. It is not! It brings us back to the fundamental difference between extension and expansion. The inner part of an orogen is in expansion: its volume and mass increase due to a supply of new light material (at the origin of the intrusive bodies). The expansion is evidently compressive by nature due to the wedge effect. Eventually, there is extension just atop the expansion, at the surface due to gravity spreading, but this is a side effect.

Erakivnor wrote:What I am questioning are exactly the dots. I don't think they can constrain first motion (either P or T points), not for M1 earthquakes at tens of km depth. Moreover if you look carefully at the dots they present they are all mixed and not very easy to distinguish between P and T signals.

If you are questioning the dots, then you are questioning the quality of the recordings. They used more than 17500 focal mechanisms with M>=1 (not uniquely M=1 as you paint it).

Erakivnor wrote:Not really strong...none of the presented data can lead to a mass balance of significant crustal imput.

The evidence support crustal expansion. I can hardly see how one can envisionned a crustal expansion without any input.

Erakivnor wrote:

Florian wrote:
This is factually incorrect. Thrusting induced by an expanding crustal structure does not lead to a net surface reduction.
That is, at a different scale, like water freezing in a rock crevice. The expansion of water induces an outward pressure which leads to the equivalent of reverse faulting in the rock without any net surface reduction of the rock.

Surface geology clearly disprove what you are saying: avery single orogen shows compressional features that account for shortenings up to one/two orders of magnitude of extensional features (i.e. normal faults). For example look at the Hymalaya and the tibetan plateaux. Or the Andes and the Altipiano (where it is present).

You confuse expansion and extension again (!) An expansional structure is like a wedge. In an expansional structure, extensional features are secondary as they result from gravity spreading of uplifted mass (in relation to the expansion).

Erakivnor wrote:
Gravitational push is induced by differential stress due to different topographic heights and/or lateral density contrast.
It can be demonstrated that lateral differential stress (gravitational push) is equal to: 1/2*g*h*D(1-D/d) where g is the acceleration, h is the height of the considered column, D is the density of the considered column and D/d is the density contrast.
For the contrast with air a simplification would be to assume non-balanced lithostatic pressure. Therefore the pressure can easily calculated as the lithostatic pressure itself.
Another way to calculate is to set a gravity "anomaly" equal to the height of the considered topography and calculate the difference in potential between mean regional geoid and the anomaly (being the potential the work required to move a mass from one point to another of the field you substitute the mass of your topography and get the work).
Stresses generated for example between an "oceanic" crust and "continental" crust 35km thick yield values of about 50-100 MPa.
For a vertical column of granite 8km tall the stress would be about 212 MPa (in contrast to air). 212 MPa is enough to fault rocks (in brittle condition they can yield 100-180 MPa as a rough approximation).
To make a clearer example without calculations: The african rift.it is uplifted by about 2000m respect to the surrounding plains of the continent (the former Pan-african orogens n.d.r.) and doesn't thrust away. With a topographical gradient not even the tibetan Plateau can thrust away with its present elevation (but it has been shown that it collapsed to the present position instead).

OK, but that is for an homogenous block in absence of surface of décollement. But you know that nappes always involve a surface of décollements. I guess that the calculation would depend on the properties of the layer playing the role of the décollement surface. The topographic heights necessary for important displacement is logically not so high. Again, do you have any order of magnitude?

Erakivnor wrote:Actually geophysical and geological evidences points into the opposite direction about what you say about rifts (magma sources, normal faults that lead to "expansion" etc. etc.)

1) I did not say that normal faults lead to "expansion". I say that tension leads to rifting (hence normal faults).
2) I say that the magma source is the upper mantle not a deeper source. Do you claim that the magma source under a ridge is the deep mantle?

Erakivnor wrote:but I'm more interested in one thing: why expansion should work differently form one part to the other?

There is no such thing as "expansion that should work differently"! There is either expansion of the crust (a consequence of a large input) or extension of the crust (without input, or just the input to fill the voids).

Erakivnor wrote:

Florian wrote:
Excuse me, but you clearly accused someone of "jumping from the occurrence of diapirism to mass-addition-to-the-Earth" as shown by the quote above. And this accusation is rootless.

That's not an accusation, is simply remarking inconsistency between data and conclusions. Then if you want to take that as an accusation...well I don't care

But this is a connection (occurence of diapirism=mass addition to earth) that you invented yourself!
This is a strawman and that's bad.

Erakivnor wrote:
Except that is difficult to see misunderstandings in evidences like thrust diplacements, shape of orogens, uplift/folding/faulting time and space relationships et cetera...why don't you then present the EE theory of orogenesis as you think about that? I tried to make a summary of what I've read and what you wrote but probably YOUR summary would be more compelling no? And then we can start to discuss from that post.

This is exactly what I've done in the last messages: present orogenesis as I think about it. But you are not really listening or you would have understood the difference between extension and expansion, and the corollary that a ridge and an orogen are different animals.

Erakivnor wrote:A couple of questions editing the figure you posted:

How many diapirs are there?

How many highlighted diapiric regions? 3 on this figure.

Erakivnor wrote:
How can they spread pressure if they are lower than the margins they are "overthrusting"? How do they exert horizontal pressure?

The body of diapirs is expanding and act like a wedge. Horizontal pressure results from the wedge effect.

Erakivnor wrote:Also, if you take the segments in chronological order (not the stacked sequence of the image) they are clearly linear. From a diapir I would expect more curved thrusting, as it occurs in some way in the Hawaii

Because they eventually developed from preexisting linear structures that are zone of weakness (megashear zone for example). Think about a hernia.

To answer the comments in the figure: these zones of diapiric activity do not necessary have an isotropic activity, hence diachronous thrusting and absence of regular symmetry.

Deleted content (duplicate post)

Sorry macdoc all of that stuff has already been rebutted handwaved away in this thread.

Macdoc wrote:cut to the chase.....

http://en.wikipedia.org/wiki/Expanding_Earth

Paul Dirac suggested in 1938 that the universal gravitational constant had decreased in the billions of years of its existence. This led German physicist Pascual Jordan to a modification of general relativity and to propose in 1964 that all planets slowly expand. Contrary to most of the other explanations this one was at least within the framework of physics considered as a viable hypothesis. [12]
Measurements of a possible variation of the gravitational constant showed an upper limit for a relative change of 5•10−12 per year, excluding Jordan's idea.[13]
[edit]Scientific consensus

The theory had never developed a plausible and verifiable mechanism of action, but neither had any of its competing theories.[1] By the late 1970s the theory of plate tectonics made all other theories obsolete following the discovery of subduction, which was found to be an important part of a mechanism of action.[1]
Generally, the scientific community finds that there is no evidence in support of the Expanding Earth theory, and there is evidence against it:
Measurements with modern high-precision geodetic techniques show that the Earth is not currently increasing in size to within a measurement accuracy of 0.2 mm per year.[14] The lead author of the study stated "Our study provides an independent confirmation that the solid Earth is not getting larger at present, within current measurement uncertainties".[15] The motions of tectonic plates and subduction zones measured by a large range of geological, geodetic and geophysical techniques supports plate tectonics.[16][17][18]

Mass accretion on a scale required to change the Earth's radius is contradicted by the current accretion rate of the Earth, and by the Earth's average internal temperature: any accretion releases a lot of energy, which would warm the planet's interior.

Expanding Earth models based on thermal expansion contradict most modern principles from rheology, and fail to provide an acceptable explanation for the proposed melting and phase transitions.

Paleomagnetic data has been used to calculate that the radius of the Earth 400 million years ago was 102 ± 2.8% of today's radius.[19][20]
Examinations of data from the Paleozoic and Earth's moment of inertia suggest that there has been no significant change of earth's radius in the last 620 million years.[21]

fucking unreal what supposedly sensible people will waste their time on ....

Really it's not. It's just human psychology that people want to feel special and for some people they link their personal worth to their beliefs. Some will be convinced by smart sounding people and flashy presentations. Others may have their own motivations but what I listed creates the backbone of a pseudoscience like EE.

EE is a based on scientific empirical evidence and is testable. By definition, it is not a pseudoscience.
@Erakivnor, see how they try to derail the discussion despite our effort to discuss scientific evidence and move forward. This is witch-hunting, not skepticism.
Waiting patiently for your reply in the meanwhile.

Florian wrote:EE is a based on scientific empirical evidence and is testable. By definition, it is not a pseudoscience.

Looking forward to your peer reviewed paper then.

BlackBart wrote:
Looking forward to your peer reviewed paper then.

Why mine?

Why not this peer-reviewed paper which existence refutes the claim that EE is pseudoscience, and which describes how the theory emerged:

SW Carey "The Expanding Earth-an Essay Review" Earth Science Reviews, 11 (1975) p 105-143. (pdf reprint HERE*)

To come back on the current topic, what are your critics concerning fig3 of the paper?


*I post a link to this copyright-protected material as there is still no decision from the moderation/administration team regarding this practice.

Florian wrote:

BlackBart wrote:
Looking forward to your peer reviewed paper then.

Why mine?

Might be a better use of your time than posting in generic internet fora - if your theory is true, the consequences would for science would be mind blowing. No-one ever won a Nobel by arguing on the internet.

Why not this peer-reviewed paper which existence refutes the claim that EE is pseudoscience, and which describes how the theory emerged:

SW Carey "The Expanding Earth-an Essay Review" Earth Science Reviews, 11 (1975) p 105-143. (pdf reprint HERE*)

Fine and dandy. But, if it's that robust why are you still arguing about it on the internet thirty-seven years later?

To come back on the current topic, what are your critics concerning fig3 of the paper?

I don't have any. As a layman I don't have a horse in this race -- if you can provide robust evidence that PT wrong then cool biscuits. But what troubles me is most is that EE proponents seem to whine about witch-hunts and conspiracies every time someone criticises it. That and the chosen battlefield seems to be the internet and youtube rather than any kind of pragmatic academia makes people tend to view EE in being closer to UFOs and Bigfoot rather than the Higgs Boson.

BlackBart wrote:
Might be a better use of your time than posting in generic internet fora - if your theory is true, the consequences would for science would be mind blowing. No-one ever won a Nobel by arguing on the internet.

Don't get me wrong. This forum is just a hobby and is insignificant in term of scientific activity. But I think that popularizing this theory (BTW not mine!) does worth something. Especially because what is apparent of this theory on the internet is not representative of the theory.

Besides, I'm interested in the perception by other earth scientists, and there are some on these fora (like Erakivnor). This may help to pinpoint what's wrong in their perception of the theory.

Fine and dandy. But, if it's that robust why are you still arguing about it on the internet thirty-seven years later?

Because the theory has so profound implications that it induces self-deceptions which culminate in plate tectonics.

BlackBart wrote:

Florian wrote:
To come back on the current topic, what are your critics concerning fig3 of the paper?

I don't have any. As a layman I don't have a horse in this race.

I'm sure @Erakivnor has many critics because this corresponds to his perception of orogenesis in EE.
But this description is wrong because Carey never understood that diapirs are not systematically tensional features. Huge compressive forces result from "not just spreading" but expanding diapirs.