Snowball Earth - Does Ongoing Vulcanism rule this out ?

[markearthling]

Gday

 

This process supposedly started 650 million years ago when all the worlds' land masses

were grouped together in a supercontinent positioned near the equator and runaway

"weathering" took massive amounts of CO2 out of the atmosphere and hence lowered

the earths' temperature so that massive ice sheets formed and extended from both

poles towards the equator eventually covering the whole globe.

 

Supposedly the earth was an ice covered snowball like this for another 25 million years

until vulcanism eventually reversed this situation and the green house gases produced

melted most of the ice and raised the earths' temperature again.

 

I am assuming that vulcanism has been ongoing since the earth formed.

If so then there seems to be a big problem with this theory.

Surely vulcanism around the planet would have always been pumping more CO2

and other greenhouse gases into the atmosphere so this would have counteracted

any effects of weathering out of CO2. I can't then see how any snowball earth process could

have gotten started let alone lasting 25 million years ( again no vulcanism ?).

 

Drop stones are another point in question here. People assume that because these

things are found in deserts that they point to transport by glaciers dating back

to snowball earth but the truth is they could have been depossitted by glaciers

from any ice age in the past. I am informed the earth has ice ages around

every 100,000 years which gives us a few to choose from.

 

Interested in what others think about the snowball earth idea.

[Moontanman]

Volcanism is not constant and a snow ball earth would have allowed released CO2 to build up when a non iced up earth would have removed it via weathering.

[markearthling]

Moontanman

 

So how do people know how much vulcanism was happening at different times in the past ?

 

It still seems likely to me that vulcanism would have counteracted weathering.

So a snowball earth could not form in the first place.

 

Are we saying that for 25 million years vulcanism reduced and then magically

ran rampant and melted the snowball ? Where is the proof that this ever

happened ?

 

The weathering argument is not convinceing. Sounds like a pseudo science

argument.

[Moontanman]

Volcanism is not constant, there are times of relative quiet and times that nearly everything seems to be erupting. But even if volcanism was constant the weather of the land could indeed remove so much of it that the Earth could freeze (remember the sun also had a lower output them as well) but if the Earth did freeze over then weathering would all but stop, CO2 could build back up till it overcame things like high albedo caused by the ice. It's a positive and negative feed back system, sometimes it gets out of kilter. The more ice you get the more heat is reflected out into space, even with high CO2 levels, so once the earth froze over it would take very high levels of CO2 to bring her back out of the deep freeze and the records left in rocks seems to indicate the snow ball earth was followed by very high temps for a short while. Of course much of the details is speculation but there is evidence of a snow ball earth at least twice in the geological record, once it was triggered by life removing CO2 and replacing it with oxygen.

[Ophiolite]

Drop stones are another point in question here. People assume that because these

things are found in deserts that they point to transport by glaciers dating back

to snowball earth but the truth is they could have been depossitted by glaciers

from any ice age in the past. I am informed the earth has ice ages around

every 100,000 years which gives us a few to choose from.

 

Moontanman has adequately addressed the variability of volcanism and the need for a substantial build up of carbon dioxide to cause a reversal of the ice age. I want to handle the dropstones.

 

People don't make assumptions. Nor are dropstones specifically found in deserts. The dropstones are found in rock sequences that date from the specific periods in question and are found at a variety of paleolatitudes. It is true that recently ice ages have occured every 100k years or so - strictly speaking we are currently in an ice age. There is absolutely no risk that we could confuse recent ice age rocks with preCambrian rocks.

 

You ask what our thoughts are about Snowball Earth. I am satisfied that there were periods of extensive glaciation, but am not yet convinced that there was total coverage of the globe. Ongoing research should clarify this within the decade.

[markearthling]

Drop stones have been found in deserts in Australia and elsewhere but I am not saying

deserts are the only places they are found. Apparently they also carry a unique

magnetic signature which supposedly fixes their point of origin.

 

Moontana says above that the snowball earth phenomena is based on speculative ideas

and then goes on to say that snowball earth has happened more than once.

A little confusing or is that just the scientific technique at work again ?

 

Ophiolite is not convinced about total global coverage of ice

and yet this idea is based on rock solid science.

 

Noone has yet explained convinceingly why volcanism

just shut down 650 million years ago for 25 million years

(doesn't sound credible) to the degree that runaway weathering out of CO2 tipped us into snowball earth. Whether volcanism

is variable or not doesn't mean no volcanism for 25 million years ?

[Ophiolite]

Mark,

yur observations in this thread and that on dating techniques suggests you have a limited familiarity with the topics you are discussing. This is perfectly natural and there is nothing whatsoever wrong with it. I do question, however, the conclusions that you then reach based upon a limited and inadequate understanding, which more often than not seems to be a misunderstanding. For example:

Drop stones have been found in deserts in Australia and elsewhere but I am not saying

deserts are the only places they are found.

It is irrelevant what the current climate is in the places where bedrock exposures reveal dropstones. The fact that you initially stipulated dropstones were found in deserts and that you repeat the observation here and then compound it by noting that they are found in 'other places' suggests that you do attach significance to the current climate/environment of dropstone exposures. That betrays a fundamental misunderstanding of what is being observed.

 

 

Moontana says above that the snowball earth phenomena is based on speculative ideas

and then goes on to say that snowball earth has happened more than once.

A little confusing or is that just the scientific technique at work again ?

With all appropriate respect to Moontanman he is not, as far as I know, a qualified geologist and certainly not one working in this specialised area, nor is this a peer reviewed science journal. Occassional imprecise writing in this context is a reflection on Moontanman and not on science.

 

Ophiolite is not convinced about total global coverage of ice

and yet this idea is based on rock solid science.

This is not my first rodeo mark, so don't play games with me. Erecting strawmen is a cheap trick. Don't play that one again or this discussion is over. No one here has said this idea is based on rock solid science. There are enough question marks for the total coverage to be debated. I haven't consulted any recent research to see quite where we stand now. Until I see that research that provides strong evidence one way or the other I remain "not convinced". That is an appropriate scientific position to take.

 

 

Ophiolite is not convinced about total global coverage of ice

and yet this idea is based on rock solid science.

 

Noone has yet explained convinceingly why volcanism

just shut down 650 million years ago for 25 million years

(doesn't sound credible) to the degree that runaway weathering out of CO2 tipped us into snowball earth. Whether volcanism

is variable or not doesn't mean no volcanism for 25 million years ?

Another strawman - volcanism did not shut down for 25 million years, so we do not need to explain something that did not happen.

Have you actually read any of the research in this area? If so, tell me what you have read. Otherwise I'll give you a reading list that will help overcome your current ignorance.

[markearthling]

If you have some links then fire away.

 

On the one hand Moontana says Volcanism is not constant

and you say it did not shut down for 25 million years

(exactly what I am saying).

 

If we are saying that volcanism is variable then all I am saying is

that given volcanism may have been variable it was still ongoing

650 million years ago and as such I cannot see how this process

would not have counteracted any weathering process that

could start a snowball earth in the first place.

 

You say I am playing games and erecting strawmen.

I am simply trying to get some kind of conclusive response

to the above.

 

If you think I am game playing then you are missing the point.

 

Check the other thread. I am totally open to your challenge.

[Moontanman]

If you have some links then fire away.

 

On the one hand Moontana says Volcanism is not constant

and you say it did not shut down for 25 million years

(exactly what I am saying).

 

No you are saying it could not have slowed down enough to cause snowball earth and you might be correct, it could very well be that volcanism had nothing to do with snow ball earth. unicellular plants may have been the cause by removing CO2 from the air faster than volcanoes of the time could put it back but once the earth was iced over such removal whether from weathering or photosynthesis stopped. This allowed CO2 to build back up in the atmosphere no matter what it's source but volcanoes would be the most likely source of such CO2, it would have taken a lot more CO2 to raise the temps with a snow ball earth due to the albedo of snowball earth than it would take with out the ice. But on the other hand it is indeed demonstrable that volcanism is indeed variable, you seem to think it is not. A huge uptick in Volcanism has almost wiped out life on earth at least twice, I see no reason to assume there could not have been long quiet periods of volcanism as well. Is has been suggested that we are now living during what amounts to a relatively quiet period in the geology of the Earth.

 

If we are saying that volcanism is variable then all I am saying is

that given volcanism may have been variable it was still ongoing

650 million years ago and as such I cannot see how this process

would not have counteracted any weathering process that

could start a snowball earth in the first place.

 

I think I already addressed this but why do you think that volcanoes had to be putting out more CO2 than could be removed by weathering 650,000,000 years ago?

 

You say I am playing games and erecting strawmen.

I am simply trying to get some kind of conclusive response

to the above.

 

Ok, i gave it to you...

 

 

If you think I am game playing then you are missing the point.

 

I know what it sounds like you are doing but I won't go there until we sort this out as closely as possible.

 

Check the other thread. I am totally open to your challenge.

 

I am currently addressing this thread.... here are four videos that do a good job of explaining this process #2 and #4 are probably most pertinent to this discussion..

 

 

 

 

[markearthling]

moontanman

 

Thanks for your thoughtfull responses above and the videos.

 

On the subject of long term quiet periods of volcanism it seems

hard to accept that this would go on for 25 million years though ?

 

When I was referring to responding to challenges I was actually

referring to a discussion I was having with Ophiolite

over at Organic chemistry ( Radiometric dating now at earth sciences).

 

But if you put any information my way I will do my best to review it.

[Moontanman]

moontanman

 

Thanks for your thoughtfull responses above and the videos.

 

On the subject of long term quiet periods of volcanism it seems

hard to accept that this would go on for 25 million years though ?

 

When I was referring to responding to challenges I was actually

referring to a discussion I was having with Ophiolite

over at Organic chemistry ( Radiometric dating now at earth sciences).

 

But if you put any information my way I will do my best to review it.

 

 

You are making quite an assumption here, I thought the videos did a pretty good job of pointing out that volcanism didn't have to stop for snow ball earth to happen.

[Ophiolite]

Drop stones are another point in question here. People assume that because these

things are found in deserts that they point to transport by glaciers dating back

to snowball earth but the truth is they could have been depossitted by glaciers

from any ice age in the past. I am informed the earth has ice ages around

every 100,000 years which gives us a few to choose from.

I am returning to the dropstone issue again, since your observations on this are laced with misinterpretation. Let's look at this in the sort of detail you should really be applying before you start questioning current consensus views.

 

You think these dropstones are found in deserts (and later concede, in other places) and that this is evidence for them being transported by glaciers. This is an understanding, sufficiently warped to be quite wrong.

 

Firstly, the dropstone character, including why we know them to be dropstones is dealt with in several places. (e.g. 1,2,3)

 

Secondly, your tie in with desert locations likely arose as follows. The notion of Snowball Earth grew out of research on a rhytymically layered siltstone in the Elatina Formation in the Flinders Ranges, a desert area, in Australia. (4) This formation includes diamictites and dropstones deposited from ice rafts. The glacial nature of these deposits is not disputed. (If you wish to dispute it, please bring forward factual observations to support that dispute.)

 

There is no way in which these dropstones "could have been depossitted(sic) by glaciers from any ice age in the past". Your suggestion that this is so reveals that you have a) no idea what a drop stone is; b) no idea of their emplacement within other sediments; c) no idea of the associated sediments which exhibit a glacial origin.

 

Given the depth of your misunderstanding on this issue do you still maintain your understanding of the possible character of volcanic activity in the Neoproterozoic and its influence on a Snowball Earth scenario is sufficient to allow you to have a relevant opinion on the issue?

 

1. Lemon,N.M., Gostin,V.A. Glacigenic sediments of the late Proterozoic Elatina Formation and equivalents, Adelaide Geosyncline, South Australia. In: The Evolution of a Late Precambrian—Early Paleozoic Rift Complex: the Adelaide Geosyncline. 1990

2. Coats R.P., Preiss W.V. Stratigraphic and geochronological reinterpretation of late Proterozoic glaciogenic sequences in the Kimberley Region, Western Australia Precambrian Research Volume 13, Issues 2-3, November 1980

3. Williams, G.E. Late Precambrian glacial climate and the Earth’s obliquity. Geol.Mag., 112, 441–444 1975.

4. Kirschivink, J.L. Late Proterozoic Low-Latitude Global Glaciation: the Snowball Earth In: J. W. Schopf & C. Klein (eds.), The Proterozoic Biosphere: A Multidisciplinary Study. Cambridge University Press, 1992.

[markearthling]

Ophiolite

 

Good to have you back.

 

On the drop stone issue I do admit that there is much I do not know regarding this subject

and much I have yet to learn. So yes my interpretations could be way out.

 

I am busy currently taking up your challenge from our previous discussions.

I have been quoted many online resources from many helpfull people here

such as yourself. I have started to go through it and it will take some time

but hopefully as I proceed my input here will become more relevant and more

focussed.

 

At no time were my intentions to insult yourself or anyone else here and I am not

into playing games with people. The bottom line for me is getting at and identifying

scientific truth. If anything I said before seemed insulting or was upsetting then I

simply say it was unintentional and I fully apologise.

 

However, I am a curious person and have a questioning mind and I will pursue

my goal until I find the right solution. I was a computer programmer/technician and general

IT worker for many years from the early 80s, left the industry for a few years

then retrained in 2000 in all things PCs (hardware/software/OS/NOS etc), Internet

and networking and now two of my major interests include the communications

and electronics fields ( an interest from my lower school days ).

 

You may be aware that computer programming is as exacting a field that there is

and I understand there are many fields like this. If a microprocessor/computer

executable file (the binary code that processor chips execute at the low level)

is wrong or currupted by just one binary bit then the program will generally

crash at the point where the bad instruction is located or this malfunction

could flow onto making the program crash at another place in the code

for other reasons I will not go into here. The magnetic bits encoded on the

tracks, sectors and platters of fixed hard disk drives are also corrupted

occasionally for many reasons and sometimes by bad computer code

and this causes many crashes on Windows and other systems.

 

So binary executable program files for computers must generally be perfect

( although programs will sometimes run even if corrupted and damage is not

critical ) and one bad instruction can bring a system crashing down

( example : windows blue screen of death or Windows "An invalid instruction has

been executed etc"). This is only one example where everything has to be just right

with many technologies for things to work.

 

So basically I am very fussy about getting things right and take pains to find

the best solutions to problems. My previous work of decades has demanded

that I be like this and I apply the same principles to many other areas of my life.

 

On the subject of snowball earth again and the drop stones I recently saw the

catastrophe program regarding snowball earth ( hosted by presenter Tony Robbins

from UK and of Time Team fame [ do you remember the character

of Baldrick which Tony played in the history/farce based Black Adder series

from the past ?) on TV and that kicked this thread off as I was curious to learn more

about the snowball earth idea from knowledgeable people like yourself.

 

On the drop stones the program did mention that some of these were found in Australia

( eg desert in Flinders ranges ) and maybe a desert somewhere in the US and I'm sure

that they mentioned other places where these things can be found ( and yes as you said above

not necessarily in deserts and I understand that current climate is not relevant here ).

They were the examples that were quoted in the program and that is why I quoted what

I did above. Perhaps I did the wrong thing in doing that.

 

In future I will do my best to research/investigate the available science literature

available online before I come here and post. I normally do this for other things

but in this case I didn't and this probably was the wrong thing to do.

My actions caused a lot of unecessary misunderstanding

( too eager to pursue the questions at hand ).

 

As regards to volcanism again I have a lot to learn. My intention above simply

related to the fact that a question arose in my mind and that was

"If volcanism has been ongoing since the earth formed then why would it just

decrease from around 650 million years ago to the point that it could not

counter some new major weathering process which tipped us into a snowball

earth scenario. In fact if volcanism was still happening around the earth back

then I can't see how the snowball earth scenario could start in the first place

and continue for another 25 million years ?".

 

People above have mentioned that volcanism is not constant, is variable

over time and has periods of relative quiet. I can comprehend what

these things mean generally speaking. But as Ophiolite has pointed

out above I need to learn more from the literature before I pursue this

subject any further.

 

Quote from Montanman above

 

No you are saying it could not have slowed down enough to cause snowball earth and you might be correct,

 

End Quote

 

Perhaps Montanman should not have encouraged me like that.

 

So anyway I hope this is a new start and a step in the right direction anyway.

 

Thanks for your honesty and direction.

 

I will catch you later.

[Moontanman]

 

Quote from Montanman above

 

No you are saying it could not have slowed down enough to cause snowball earth and you might be correct,

 

End Quote

 

Perhaps Montanman should not have encouraged me like that.

 

 

 

You quote mined me! Did you think I was too stupid to know? How insulting! Typical dishonest creationist tactic, at least you could have given the entire quote and not one part of it out of context.

 

No you are saying it could not have slowed down enough to cause snowball earth and you might be correct, it could very well be that volcanism had nothing to do with snow ball earth. unicellular plants may have been the cause by removing CO2 from the air faster than volcanoes of the time could put it back but once the earth was iced over such removal whether from weathering or photosynthesis stopped. This allowed CO2 to build back up in the atmosphere no matter what it's source but volcanoes would be the most likely source of such CO2, it would have taken a lot more CO2 to raise the temps with a snow ball earth due to the albedo of snowball earth than it would take with out the ice. But on the other hand it is indeed demonstrable that volcanism is indeed variable, you seem to think it is not. A huge uptick in Volcanism has almost wiped out life on earth at least twice, I see no reason to assume there could not have been long quiet periods of volcanism as well. Is has been suggested that we are now living during what amounts to a relatively quiet period in the geology of the Earth.

[markearthling]

Moontanman

 

I did not intentionally "Quote Mine" you as you said and I did not intend

to quote you out of context.

 

It was simply an attempt (perhaps a weak one) at some humour.

 

I understand that you went on to explain that it is possible that a change

in the level of volcanism may have had nothing to do with the development

of the snowball earth scenario and that there may have been other reasons.

 

I understood your context in your original quote when I first read it.

 

I had no intention to dishonestly misrepresent what you said.

 

You are misreading my actions/intent above.

 

I was only trying to be funny when I was talking to Ophiolite.

Please understand this.

 

You have already been very helpfull to me so why would I try to do

that to you ?

 

Also, surely personal beliefs should not come into this discussion.

We all have them.

 

I am sure you are an objective and sensible person and will

consider what I have said.

[Ophiolite]

On the drop stone issue I do admit that there is much I do not know regarding this subject and much I have yet to learn. So yes my interpretations could be way out.

As I have stated, I think they are. I believe this is because you have taken a simplistic view of the topic, relying - perhaps - on popular accounts of the issue These can rarely adequately deal with a topic in the depth required for a thorough judgement.

 

At no time were my intentions to insult yourself or anyone else here and I am not into playing games with people.

I accept this, but I have to tell you that you have insulted people. Some people deserve to be insulted. Your targets have been inappropriate and your attacks have made you appear like a self-indulgent, ignorant asshole. I accept your apology for the posts that have created this impression, but you will understand that my acceptance is conditional on your future conduct.

 

I was a computer programmer/technician and general IT worker for many years from the early 80s, left the industry for a few years then retrained in 2000 in all things PCs (hardware/software/OS/NOS etc), Internet and networking and now two of my major interests include the communications and electronics fields ( an interest from my lower school days ).

In 1964, at secondary school, I built a circuit with transistors for adding two sets of binary numbers together and displaying the results with lights. I called it BASIL - Binary Adder Subtractor with Indicator Lights. I wrote a suite of programs for monitoring drilling rig operations in the early 1970s. I ran a small team of programmers in the late 1970s. I used to troubleshoot electronic euqipment to the component level. I wrote machine language code for mini-computers, on the fly, to diagnose problems. I was part of a four man team in the 1990s that laid out the specifications for a large technical data base. I know software. I know hardware. I know the mindsets needed to work with these.

 

 

That's just one of the areas of expertise I have been involved in. I've also set up quality systems for companies. ISO9001 is part of my working vocabulary.

So basically I am very fussy about getting things right and take pains to find the best solutions to problems. My previous work of decades has demanded

that I be like this and I apply the same principles to many other areas of my life.

Today I teach about the drilling process. One of the things I tell my students is that there is no ISO9001 for sedimentation. Geology is a hell of a lot more random than a J-K flip flop. You need to adopt the mind set appropriate to the subject. Geology is not as clear cut as the input of a logic probe.

 

As regards to volcanism again I have a lot to learn. My intention above simply related to the fact that a question arose in my mind and that was "If volcanism has been ongoing since the earth formed then why would it just decrease from around 650 million years ago to the point that it could not counter some new major weathering process which tipped us into a snowball earth scenario. In fact if volcanism was still happening around the earth back then I can't see how the snowball earth scenario could start in the first place and continue for another 25 million years ?".

I don;t know where you got the idea that you were challenging. The research literature does not offer that idea in such simplistic terms, though some elements of what you are saying can be recognised in the research. However, this is why you have been given a hard time. In essence you have been setting up a strawman that has an element of truth, but is essentially inaccurate, and then attacking it. That is not a productive use of brain cells.

 

Here is a useful review articlefrom 2002 that conveys some of the complexity of the issues. There has been a ton of research in the decade since then that explore this topic. I estimate around 400 published papers in that time. At one point you were implicitly critical that I expressed reservations about the snowball Earth hypothesis. Until and unless I have read at least the abstracts of at least half those papers, and the full text of at least the most important two dozen, I'm not in a position to have a clear view on the matter.