Blogging Batholiths

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I am currently in British Columbia, Canada, participating in the Batholiths Onland experiment.

Nominally, this large group effort involving over 50 scientists and grad students is for “a seismic refraction and wide-angle reflection survey across the Coast Mountains batholith of British Columbia, Canada.”

This rather terse description does not really do justice to the project, which has the purpose of discovering why continental mountain ranges are often made of granite instead of basalt.

Relevance to the Panda’s Thumb? (1) Real science involves real work; when is the last time you saw a creationist actually measure something, or use a shovel? (2) Real scientists think the earth is billions of years old. You just can’t scientifically reconcile these batholiths with a 10,000-year old earth without being more than a little schizophrenic.

This phase of Batholiths is for performing seismic imaging of the crust and mantle below the Canadian Rocky mountains in British Columbia, one of the largest collection of batholiths (from the Greek bathos, depth + lithos, rock, a large mass of intrusive igneous rock believed to have solidified deep within the earth) in the world. My part of this experiment is as one of six IRIS/PASSCAL scientists assisting with the seismic ranging for the project. This involves deploying thousands of seismic sensors and recorders across British Columbia, and recording responses to several man-made detonations. These responses can then be analyzed to yield, first, seismic velocity profiles; these are then related these to variables such as density or temperature, which in turn are related to chemical composition of the crust and mantle. Many other sources of data are also used, including gravitometric measurements, geochronology, broadband recordings of natural earthquake tremors, and more.

During my discussions with John Hole, one of the project’s Principal Investigators (PI’s) from Virginia Tech (but a native Canadian, and glad to be working there again), I learned that that basic goal of the project is to locate the “missing pyroxenes.” In brief, as the mantle is distilled chemically below the crust, the result is primarily gabbro, a mafic rock quite similar to basalt in chemical composition. Further distillation of gabbro can remove the pyroxene components, leaving what is basically granite which we see in these huge, beautiful batholiths.

But, where do the pyroxenes go? Are they hiding between the crust and the mantle? Are they melted back into the mantle? Why are mountain ranges not always formed from huge basaltic lava flows? Why is there so much granite in continents?

This project will be ongoing for several weeks in July 2009. For a photographic tour showing what it’s like to work on a “Big Science” project, log in the Batholiths entry to the NMSkeptic blog. Comments may be left here (MT4 willing) or there, but no where in between.

38 Comments

Actually, the YECs have recently been making a bit of a fuss about how they can explain this aspect of geology. Andrew Snelling apparently has a model, which explains everything amazingly well and much better than conventional theories etc etc:

Snelling A. A. 2008. Catastrophic granite formation: rapid melting of source rocks, and rapid magma intrusion and cooling. Answers Research Journal 1:11-25.

http://www.answersingenesis.org/con[…]ormation.pdf

he even measures something in this paper:

Snelling A. A. and Gates D. 2009. Implications of polonium radiohalos in nested plutons of the Tuolumne Intrusive Suite, Yosemite, California. Answers Research Journal 2:53-77.

http://www.answersingenesis.org/con[…]Granites.pdf

perhaps your geological colleagues would be interested in these papers, to learn where they’ve been going wrong all these years.

Oh and you can read about Snelling’s hypothesis here. It touches upon polonium halos and Tom Ballieul who wrote the Talk Origins critique of YEC polonium work shows up in the comments.

http://thenewcreationism.wordpress.[…]s-primordial

Dave Thomas Wrote:

(2) Real scientists think the earth is billions of years old. You just can’t scientifically reconcile these batholiths with a 10,000-year old earth without being more than a little schizophrenic.

For the benefit of readers who are relatively new to the “debate”, many creationists, probably most of the ones who have spent considerable time thinking about it, also think that the earth is billions of years old. What makes most of them at least as “schizophrenic” as the YECs, however, is that they don’t consider the radical differences in different ages “important”.

YECs and OECs don’t mine their own data because they know that the answers will either validate evolution or at least contradict the claims of other creationists. So they must resort to mining (removing from context) the data and quotes obtained by the hard work of real scientists. So once again I am reminded of Pope John Paul II, who spoke of the “convergence, neither sought nor fabricated” of evidence for evolution. In stark contrast, despite decades of seeking and fabricating “evidence,” creationists’ conclusions have only been diverging into “don’t ask, don’t tell.”

(1) Real science involves real work; when is the last time you saw a creationist actually measure something, or use a shovel?

Yeah, they just take their assumptions for granite.

As one who has only learned about geology in adult education evening classes and field trips the question,”Why is there so much granite in continents”, seems fairly easy to answer. Granites are less dense than other igneous/plutonic rocks and rise through the surrounding strata. They are also less prone to certain methods of erosion than the surrounding rocks which helps them stand out.

Am I digging a hole for myself?

About the pyroxenes, I should also be interested in their demise!

Oh, don’t worry about the granites, in a few million years they may sink and have a sedimentary cover, depending on their situation.

In my experience, YECs can spend plenty of time criticizing the various forms of OEC (one article I’ve read mentions “day-age compromisers”), probably almost as much as evolutionists. I have read one Jehovah’s Witness book that seems to critique young-earth creationism.

I was just wondering, could someone with knowledge amd experience in geology address the YEC articles in the first post? I’m not a geologist, so it would be very difficult for me to refute Snelling’s work/probable distortion.

At any rate, your photo and article are very impressive, Dave Thomas!

Henry J said:

(1) Real science involves real work; when is the last time you saw a creationist actually measure something, or use a shovel?

Yeah, they just take their assumptions for granite.

That wasn’t a very gneiss thing to say.

Stanton said:

Henry J said:

(1) Real science involves real work; when is the last time you saw a creationist actually measure something, or use a shovel?

Yeah, they just take their assumptions for granite.

That wasn’t a very gneiss thing to say.

It didn’t feel too mean, though. It feldspar for the course.

I thought JohnO got it right, although the research is hugely interesting of course; where did those pyroxenes go?

From my simplistic science high-school days, we were told merely that the less-dense continental granites, floated upon the more dense oceanic basalts; No?

I’d like to be corrected i’m not like the creationists, that is, I do give a schist! Rob.

Telamon said:

I was just wondering, could someone with knowledge amd experience in geology address the YEC articles in the first post? I’m not a geologist, so it would be very difficult for me to refute Snelling’s work/probable distortion.

At any rate, your photo and article are very impressive, Dave Thomas!

Thanks, Telamon.

I’ll just say that creationists have to really struggle with stratigraphy.

Dave

JohnO said:

As one who has only learned about geology in adult education evening classes and field trips the question,”Why is there so much granite in continents”, seems fairly easy to answer. Granites are less dense than other igneous/plutonic rocks and rise through the surrounding strata. They are also less prone to certain methods of erosion than the surrounding rocks which helps them stand out.

Am I digging a hole for myself?

About the pyroxenes, I should also be interested in their demise!

Oh, don’t worry about the granites, in a few million years they may sink and have a sedimentary cover, depending on their situation.

Ah, but the question is, how did the granites originate? The mantle after all is made up of mafic rock; if you are going to melt it into granites of lower density and higher silica content, then you need to remove mafic components, like, well, pyroxenes.

My understanding (mineralogist, not petrologist) was that the granites originated when superheated basaltic melts rose and ponded at the base of the crust. The excess heat was transferred to the more silicic crustal rocks which have lower melting points, resulting in a rhyolitic to andesitic (granite to diorite) magma that would ascend towards the surface. The melt that reached the surface produced volcanism, and any left crystallizing in the crust became batholiths, later to be exposed through erosion.

Since I am freshly back at VT, I wasn’t aware that John Hole was working on this. Say hello to him for me, Dave, (Neil Johnson) and warn him that I will try and interrogate him on this during the fall.

I’ll just say that creationists have to really struggle with stratigraphy[/URL].

That might be asking to much - this is after all rock science.

Richard said:

In my experience, YECs can spend plenty of time criticizing the various forms of OEC (one article I’ve read mentions “day-age compromisers”), probably almost as much as evolutionists. I have read one Jehovah’s Witness book that seems to critique young-earth creationism.

“Classic” YECs and OECs certainly do criticize each other - and IDers - but those criticisms are rarely in the spotlight. IDers, along with the more politically correct YECs and OECs, do their best to downplay the irreconcilable differences, and the the media plays right along because the “intra-creationism” disputes just don’t sell like a “Bible vs. Darwin” caricature. That I expect, but what drives me nuts is how seldom critics of ID/creationism exploit it. The “us vs. ‘the creationists’” approach may be necessary to begin the discussion, but if one ends it there, it only helps prop up the big tent.

BC’s a big place. Where are you? Near an airport, obviously…

Just received a forwarded message from John Hole in BC; there has apparently been an ecoterrorism incident involving the seismic work on the project. If Dave Thomas is keeping up with this post, he can explain; I’ll have to check for permission before I C&P the message.

NJ said:

Just received a forwarded message from John Hole in BC; there has apparently been an ecoterrorism incident involving the seismic work on the project. If Dave Thomas is keeping up with this post, he can explain; I’ll have to check for permission before I C&P the message.

Yowza! The only thing I could find through Google News is from Globe and Mail:

MARK HUME

VANCOUVER — From Thursday’s Globe and Mail Last updated on Friday, Jul. 17, 2009 02:29AM EDT

The RCMP have been called to a remote British Columbia island after an environmental activist “monkeywrenched” a science project in the Great Bear Rainforest, breaking open a drill shaft and tampering with high explosives to stop a seismic blast from occurring.

One of the scientists running the Batholiths Continental Dynamics Project, in which researchers from 12 Canadian and U.S. universities are planning to set off a long chain of about 20 blasts to study how coastal mountains are formed, says the protester put himself and researchers at risk and triggered an “eco-terrorism” investigation by police.

“This is serious stuff. He could have blown himself up,” John Hole, an associate professor of geophysics at Virginia Tech, said after learning one seismic site, on Denny Island, had been spiked.

“Because there are high explosives involved and because of the Dawson Creek bombings [of EnCana gas lines in northeast B.C.] this has gone all the way to Ottawa. This has triggered the eco-terrorism label with the RCMP,” Dr. Hole said.

Dr. Hole said Ingmar Lee, an environmental activist who admits to vandalizing the blast shaft, has left researchers with a dangerous problem.

“The only safe way to destroy explosives is to explode them,” Dr. Hole said. “But he has destroyed our safe detonation system.”

The idiot probably thought it was oil/gas exploration. There’s a wacko blowing up pipelines in northern BC. How well are your projects labeled?

Apparently he knew it was for geological research (even talked to Dr. Hole), but was worried it would damage the nesting grounds for sandhill cranes nearby. Even though all those explosives would have caused less damage than some naturally occurring earthquakes in the area.

Some of the comments on the article are pretty depressing to read, too.

fnxtr said:

The idiot probably thought it was oil/gas exploration. There’s a wacko blowing up pipelines in northern BC. How well are your projects labeled?

Here’s a press release Dr. Hole sent out today:

We have stabilized the highly dangerous situation created by Mr. Lee, and are prepared to respond to his criminal actions. John Hole

==== On July 14, Mr. Ingmar Lee, a self-professed community activist, informed the media that he had damaged a seismic explosive shot on Denny Island (Shearwater), in the Central Coast of British Columbia, near Bella Bella. The seismic shot was to be used by a university research group studying the granites of the Coast Mountains. Mr. Lee accompanied his claims of vandalism with a manifesto claiming imminent danger to wildlife, lack of community consultation, and ill intent of the university professors. Mr. Lee’s claims are demonstrably false.

It is a federal criminal offense to tamper with explosives. Due to sensitivity in the wake of pipeline bombings in northern BC/Alberta, Mr. Lee’s actions triggered an RCMP alert for eco-terrorism that climbed to the highest levels in Ottawa. Under the advice of provincial and federal explosives regulators, the RCMP posted the damaged shot site as highly dangerous and the community was alerted. Mr. Lee was not immediately arrested.

Mr. Lee claimed to have “disabled and destroyed” the shot. However, the explosives were still present and live. There is only one safe way to destroy explosives: detonation. Instead, at great personal risk, Mr. Lee destroyed the security and the safe detonation system. This created an increased risk for the local community.

A licensed explosives expert assessed the damage, accompanied by the RCMP. Despite repeated warnings by the RCMP, Mr. Lee returned to the site at least twice to harass the people working to make the site safe.

In the evening of July 16, a group of leaders from Denny Island gathered and accompanied the project explosives expert to the site to provide security from Mr. Lee. They provided equipment and community support for the scientists. The RCMP also provided security and official witness.

After some hours of work and at greatly increased personal risk, the licensed explosives expert repaired and detonated the Denny Island shot at 11:00pm local time on February 16. The shot shook the ground but was quiet in the air. It did not blow to the surface, and caused no surface damage. This is what seismic shots are designed to do.

Explosive detonating cord had been cut by Mr. Lee. This broken piece had to be detonated separately at the surface 15 minutes later. This was extremely loud. If there was any disturbance to local wildlife, it was caused by this noise.

The site, a bulldozed rocky area at the end of a private airstrip, was cleaned to its original condition.

The university research group hopes that the government charges Mr. Ingmar Lee for this criminal offense.

##### The university seismic project is a collaboration of 4 universities: University of Victoria, Virginia Tech, University of Texas El Paso, and University of British Columbia. The science is entirely funded by national university research funding agencies in Canada (Natural Science and Engineering Research Council) and the USA (National Science Foundation). The seismic work is part of a larger geologic project investigating the processes that created BC’s Coast Mountains. www.geo.arizona.edu/tectonics/Ducea/Batholiths/index.html

The project has no affiliation with petroleum or mineral exploration. Denny Island and the Coast Mountains are made of granite, and petroleum is never found in granite. The seismic method images subsurface geology using the same physics as medical ultrasound. The method is used for environmental, groundwater, mineral, petroleum, earthquake hazards, and tectonics research. This project’s images will “see” to >50 km depth, but at insufficient detail to find energy or mineral resources.

The explosives work was permitted over a two-year period. The permit was managed by BC’s Integrated Land Management Bureau and NSERC. The potential environmental impacts were evaluated by several federal, provincial, and local agencies and organizations, most notably the Canadian Department of Fisheries and Oceans and the BC Ministry of the Environment.

At Denny Island, the project had the approval of the Heiltsuk First Nation, on whose territory the shot lies. It had the approval of the Central Coast Regional District, a formal civic organization representing the sparsely populated region and the site of the shot. It had the approval of the corporation at whose private airstrip the shot was located. No buildings were within 1 km of the site.

– J. A. Hole, Dept. of Geosciences, Virginia Tech, 4044 Derring Hall (MC 0420), Blacksburg VA, 24061 http://www.geos.vt.edu/people/hole/

Here are some news stories and videos. The video shows the eco-activist is most concerned about oil and gas exploration. But, there is absolutely no prospect for such at Denny’s Island. Many tens of km farther west, perhaps, but not here.

http://www.vancouversun.com/technol[…]9/story.html

http://www.pacificfreepress.com/new[…]holiths.html

http://www.theglobeandmail.com/news[…]icle1220096/

http://www.vimeo.com/5618364

Cheers, Dave

Gaia preserve us from “community activists” like Mr. Lee.

you missed at least one article:

http://www.timescolonist.com/More+a[…]0168/story.i heard the CBC talk radio interviews (As It Happens) with first Ingmar Lee, and then next day John Hole.

lincoln hollister said:

you missed at least one article:

http://www.timescolonist.com/More+a[…]0168/story.i heard the CBC talk radio interviews (As It Happens) with first Ingmar Lee, and then next day John Hole.

Thanks Lincoln. There was a small typo in the link.

Try this one!

Cheers, Dave

Hi all,

It needs to be pointed out that the 2009 Batholiths Land-based Seismic Program failed to conduct any credible public consultation process which would have provide information about their project to local communities along their blast route. Certainly, nobody here on Denny Island was informed, with the exception of our representative to the Central Coast Regional District, who also did nothing to inform our community.

It appears that this secrecy was deliberate, on account of the humiliating failure of their 2007 Batholiths Marine which was quite rightly attacked by numerous respected BC Environmental Organizations, which include the David Suzuki Foundation, West Coast Environmental Law, and the Georgia Strai Alliance. A quick Google search will provide those objections. It seems apparent that as a result of the termination of that project, the Batholiths scientists deliberately chose to conduct a very minimal low-key public process, and it appears that they simply hoped that nobody would notice.

I expectat that the Batholiths Projects public information efforts were also seriously deficient in informing the public in the Bella Coola valley, and all across the Chilcotin to Quesnel. Currently, we are receiving reports that this is the case.

The Denny Island site is located right in the heart of the so-called “Great Bear Rainforest” which is an area which is internationally recognized for its significant primaeval wilderness values, and which has been afforded unique and special protections. All development in this area is expected to conform to “Eco-system Based Management” principles. There is no mention anywhere in what little information is available about the project that its proponents made any effort whatsoever to comply with these requirements, or even knew anything about them.

There are also numerous legitimate concerns about the effects of the blasts on local wildlife which were never addressed, nor was there any monitoring program by which the scientists could actually determine what, if any effects resulted.

This is an example of the worst example I have ever seen of scientific arrogance and a very shoddy, if not deliberately evasive public relations effort.

Sincerely, Ingmar Lee, Denny Island, BC

Certainly, nobody here on Denny Island was informed, with the exception of our representative to the Central Coast Regional District

Um, isn’t that what representatives and agencies are for?

Ya’ know, to be a point of contact, interface with outsiders, apply proper standards, make sure zoning and safety regulations, that sort of stuff?

from Mr. Lee:

All development in this area is expected to conform to “Eco-system Based Management” principles. There is no mention anywhere in what little information is available about the project that its proponents made any effort whatsoever to comply with these requirements, or even knew anything about them.

Please explain how seismic testing is in any way “development”, and in what specific way this particular test did not conform to “eco-system based management” principles.

Also, please clarify how the behaviour that increased the danger of above-ground explosions in any way improved on these principles.

Thank you.

Ingmar Lee said:

Hi all,

It needs to be pointed out that the 2009 Batholiths Land-based Seismic Program failed to conduct any credible public consultation process which would have provide information about their project to local communities along their blast route. Certainly, nobody here on Denny Island was informed, with the exception of our representative to the Central Coast Regional District, who also did nothing to inform our community.

Sounds like the problem is your representative. From what I’ve read of your email exchanges, the actual team made every good faith effort to ensure that people knew what was going on.

It appears that this secrecy was deliberate, on account of the humiliating failure of their 2007 Batholiths Marine …

Are you certain that one wasn’t canceled due to budgetary reasons?

It seems apparent that as a result of the termination of that project, the Batholiths scientists deliberately chose to conduct a very minimal low-key public process, and it appears that they simply hoped that nobody would notice.

That’s not “apparent.” In fact I’m wondering how you think such an inference is so blatantly obvious.

I expectat that the Batholiths Projects public information efforts were also seriously deficient in informing the public in the Bella Coola valley, and all across the Chilcotin to Quesnel. Currently, we are receiving reports that this is the case.

What sort of reports?

The Denny Island site is located right in the heart of the so-called “Great Bear Rainforest” which is an area which is internationally recognized for its significant primaeval wilderness values, and which has been afforded unique and special protections. All development in this area is expected to conform to “Eco-system Based Management” principles.

A) The science team apparently went through all the proper channel to conduct their blasts in the region. If you have reason to think otherwise, please make those clear. B) This is not “development,” it’s basic research.

There is no mention anywhere in what little information is available about the project that its proponents made any effort whatsoever to comply with these requirements, or even knew anything about them.

Try looking up in this thread, and also try re-reading your email exchanges with Dr. Hole.

There are also numerous legitimate concerns about the effects of the blasts on local wildlife which were never addressed, nor was there any monitoring program by which the scientists could actually determine what, if any effects resulted.

I’d say those concerns were addressed with finality when the charges went off, including the det-cord you damaged which had to be detonated above-ground. Be that as it may:

Dr. Hole:

The explosives work was permitted over a two-year period. The permit was managed by BC’s Integrated Land Management Bureau and NSERC. The potential environmental impacts were evaluated by several federal, provincial, and local agencies and organizations, most notably the Canadian Department of Fisheries and Oceans and the BC Ministry of the Environment.

At Denny Island, the project had the approval of the Heiltsuk First Nation, on whose territory the shot lies. It had the approval of the Central Coast Regional District, a formal civic organization representing the sparsely populated region and the site of the shot. It had the approval of the corporation at whose private airstrip the shot was located. No buildings were within 1 km of the site.

This is an example of the worst example I have ever seen of scientific arrogance and a very shoddy, if not deliberately evasive public relations effort.

I think this is one of the worst I’ve seen of “activist” arrogance and a very shoddy, if not deliberately stupid and dangerous form of criminality in the name of the environment. There was no call for you to try and sabotage a blast like that, and all throughout I’ve seen you display willful ignorance of the nature of the experiment while casting sidelong allegations of ties to fossil fuel industries and government corruption.
You do not come across as a reasonable man doing what is reasonably necessary to protect the local environment, you come across as a bit of a loon scoring own-goals against environmentalism. This whole episode is not just an ill-conceived obstruction of pure science, it’s also more ammo for those who like to portray environmentalists as half-baked extremists.
And, I mean, are your nesting sandhills even part of a threatened subspecies?

Frank J said:

Richard said:

In my experience, YECs can spend plenty of time criticizing the various forms of OEC (one article I’ve read mentions “day-age compromisers”), probably almost as much as evolutionists. I have read one Jehovah’s Witness book that seems to critique young-earth creationism.

“Classic” YECs and OECs certainly do criticize each other - and IDers - but those criticisms are rarely in the spotlight. IDers, along with the more politically correct YECs and OECs, do their best to downplay the irreconcilable differences, and the the media plays right along because the “intra-creationism” disputes just don’t sell like a “Bible vs. Darwin” caricature. That I expect, but what drives me nuts is how seldom critics of ID/creationism exploit it. The “us vs. ‘the creationists’” approach may be necessary to begin the discussion, but if one ends it there, it only helps prop up the big tent.

Yeah that makes sense. I get the feeling that the literature I read was sort of preaching to the choir anyway.

In actual response to Mr. Thomas’ post:

(1) On June 4th, in the Badlands of South Dakota.

(2) Sure you can. SteveF already pointed some of the YEC explanations, and there’s more, e.g. “Rapid Rocks” and “Rapid Granite Formation”.

NJ said:

JohnO said:

As one who has only learned about geology in adult education evening classes and field trips the question,”Why is there so much granite in continents”, seems fairly easy to answer. Granites are less dense than other igneous/plutonic rocks and rise through the surrounding strata. They are also less prone to certain methods of erosion than the surrounding rocks which helps them stand out.

Am I digging a hole for myself?

About the pyroxenes, I should also be interested in their demise!

Oh, don’t worry about the granites, in a few million years they may sink and have a sedimentary cover, depending on their situation.

Ah, but the question is, how did the granites originate? The mantle after all is made up of mafic rock; if you are going to melt it into granites of lower density and higher silica content, then you need to remove mafic components, like, well, pyroxenes.

My understanding (mineralogist, not petrologist) was that the granites originated when superheated basaltic melts rose and ponded at the base of the crust. The excess heat was transferred to the more silicic crustal rocks which have lower melting points, resulting in a rhyolitic to andesitic (granite to diorite) magma that would ascend towards the surface. The melt that reached the surface produced volcanism, and any left crystallizing in the crust became batholiths, later to be exposed through erosion.

Since I am freshly back at VT, I wasn’t aware that John Hole was working on this. Say hello to him for me, Dave, (Neil Johnson) and warn him that I will try and interrogate him on this during the fall.

John O and NJ asked some good questions here. It’s true that melts derived from partial melting of the mantle have a basaltic composition, like that of the ocean floors and of the Hawaiian Islands. As basaltic magma cools, different minerals begin crystallizing out at different temperatures, with olivine, pyroxenes and calcic feldspars coming out at the highest temperatures. The order of crystallization is given in what is known as Bowen’s reaction Series. If the magma solidifies completely, we get basalt (if it cools fast) or gabbro (if it cools slowly. What we don’t get is granite.

It’s possible, using the order of crystallization from Bowen to get granite, but it takes a little work. When a basaltic magma partially crystallizes, the molten fraction becomes enriched in silica and other compatible elements. if the solidified minerals settle out, the segregated residual magma would make a less mafic, more felsoc rock, like andesite. Keep on segregating out the crystallized material and you can eventually make a granitic magma out of a basaltic source - but it’s hard. In addition, even if the process works perfectly, the volume of granite made will only be 2% or 3% of the original melt volume. That makes granitic batholiths difficult to explain using traditional crystallization processes.

You can, on the other hand, make large volumes of granite in a different way, through plate tectonics. let’s assume no continents to start with, only oceanic crust, formed at spreading centers, and destroyed at subduction zones. As oceanic crust sinks, it partially melts, when it reaches a depth of about 300 km. A partial melt of a basaltic rock is enriched in silica, and has the composition of andesite. That’s why the volcanoes above subduction zones are made of andesite. Go ahead and visit the Antilles Islands to see what an island arc chain looks like.

As the andesite volcanoes grow, they are eroded, producing sediments surrounding them that become even more enriched in silica. A good example would be Japan, or the larger islands of the Indonesian Archipelago. Once a few of these start to collide (and not sink back into the mantle) we have a proto continent.

The bulk composition of the andesite volcanic rocks and the surrounding sediments is remarkably similar to that of granite, even though these rocks wouldn’t look like a granite. But as more and more accumulate, and get heated, they metamorphose to gneiss, or partially melt, producing a granite.

This process explains why a YEC origin of granite is simply wrong. Granite is an EVOLVED igneous rock, that takes a few spins through parts of the rock cycle before it can ever be formed. As far as rapid melting of continental crust to form a batholith during a deluge? Can’t possibly happen. just think of the amount of energy needed to melt that much rock in that short a period of time.

Mike, thanks for reminding me why I started coming here in the first place. What a great place to learn!

For a glitch at Dave’s project, see Pharyngula. It seems an anti-science ideologue sabotaged some detonation cord before one of the shots.

You’re more than 10 days behind, RBH. Look upthread. ;)

Good Morning,

I am a member of the Heiltsuk First Nation, the territory in which Mr Lee lives and where a portion of the Batholiths project is being conducted.

I have paid close attention to all events leading up to the act of vandalism and the consequent commentary afterwards. I have read the e-mail interchange between Mr Lee and Dr Hole and feel the Dr did his best to speak to Lee’s questions. I also feel Lee took matters in to his own hands to the detriment of any valid expression of concern that may be raised now or in the future with respect to unfamiliar scientific research local residents may have reason to question. Azkyroth #34 and mmr #45 (on the Blog site Pharyngula)say this quite nicely .

My issue is with the reactionary members of the scientific community that are labelling this misguided individual with inflammatory words like “moron”, “idiot” and “wacko” and the attached scorn and derision. I am sure Lee’s actions were misguided and needlessly endangered others but it doesn’t help the situation to be arrogantly dismissive.

Just as the misguided actions of one eco-activist claiming to represent the concerns of an entire group diminish that group’s voice in any subsequent challenges; so to does inflammatory scorn lobbed down from the ivory tower further entrench the separation between scientists and academics from the people they seek to enlighten.

In my opinion, both extremes are using unwarrented emotion to take unnecessary cracks at the other “side” when a middle ground is where real understanding happens.

Hope this helps.

Salistala said:

Good Morning,

I am a member of the Heiltsuk First Nation, the territory in which Mr Lee lives and where a portion of the Batholiths project is being conducted.

I have paid close attention to all events leading up to the act of vandalism and the consequent commentary afterwards. I have read the e-mail interchange between Mr Lee and Dr Hole and feel the Dr did his best to speak to Lee’s questions. I also feel Lee took matters in to his own hands to the detriment of any valid expression of concern that may be raised now or in the future with respect to unfamiliar scientific research local residents may have reason to question. Azkyroth #34 and mmr #45 (on the Blog site Pharyngula)say this quite nicely .

My issue is with the reactionary members of the scientific community that are labelling this misguided individual with inflammatory words like “moron”, “idiot” and “wacko” and the attached scorn and derision. I am sure Lee’s actions were misguided and needlessly endangered others but it doesn’t help the situation to be arrogantly dismissive.

Just as the misguided actions of one eco-activist claiming to represent the concerns of an entire group diminish that group’s voice in any subsequent challenges; so to does inflammatory scorn lobbed down from the ivory tower further entrench the separation between scientists and academics from the people they seek to enlighten.

In my opinion, both extremes are using unwarrented emotion to take unnecessary cracks at the other “side” when a middle ground is where real understanding happens.

Hope this helps.

Thanks for your comment. I think we all appreciate the feedback from someone else who is actually there. A word of warning, however: I agree with you that inflammatory rhetoric is probably not helpful, but recognize that since these are blog posts that are open to the whole world, there is no way to distinguish actual members of the scientific community from random people. And given the ‘Wild West’ nature of the Internet, it isn’t surprising that there will be some extreme statements here, as well as on the environmental blogs.

Mike:

But as more and more accumulate, and get heated, they metamorphose to gneiss, or partially melt, producing a granite.

I’m following the explanation sort of. Basically basalt gets fractionated into high silica rocks by plate tectonics.

So how do the andesites and sedimentary silica rich rocks get partially melted to form granite? They must have to get subducted and melted and then rise towards the surface but not break the surface.

So, the earliest rocks on earth can’t be granite. So when does granite first appear? And are any granite batholiths forming these days anywhere?

If anyone knows post it.

raven said:

Mike:

But as more and more accumulate, and get heated, they metamorphose to gneiss, or partially melt, producing a granite.

I’m following the explanation sort of. Basically basalt gets fractionated into high silica rocks by plate tectonics.

So how do the andesites and sedimentary silica rich rocks get partially melted to form granite? They must have to get subducted and melted and then rise towards the surface but not break the surface.

So, the earliest rocks on earth can’t be granite. So when does granite first appear? And are any granite batholiths forming these days anywhere?

If anyone knows post it.

My understanding, Raven, is that the rocks at the base of the crust are melted when superheated basalts pond there.

The basaltic melts form when the water-saturated oceanic rocks melt in subduction zones (flux melting: The water lowers the melting point). As these melts rise, they are pushed further from the basalt liquidus as the overlying pressure decreases. Once they reach the lower density lower crust, they aren’t as buoyant and don’t rise as quickly, resulting in basaltic melt reservoirs. Since these are well above the liquidus temperatures, they can transfer a great deal of heat to the crustal rocks (creating melts that are more silica-rich) without completely crystallizing. Throw in some magma mixing, and you have an intermediate silica melt - andesite. If the high-to-intermediate silica magmas crystallize at depth, you get granitoid (granite, quartz monzonite, granodiorite) plutons. Repeat for several generations of melt, and you have a batholith complex.

In this model, granites would start to form underneath subduction zone volcanoes about as soon as the volcanoes themselves. And since there are plenty of modern subduction zone volcanoes, there should be batholiths aplenty forming today.

I’m sure I’m leaving out some details and/or other pathways, but we’ll need a fer-real petrologist for that.

I’ve updated the photo essay for the whole project. Comments are closed for this post; they may now be made on the updated post.

Cheers, Dave

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This page contains a single entry by Dave Thomas published on July 13, 2009 12:52 AM.

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