ESA Return to https://www.halos.com/faq-replies/snelling-to-gentry-11-17-2002.htm. ESA

Dr. Snelling's Reply
From: Andrew Snelling
To: Dr. Robert Gentry
CC: Dr. Larry Vardiman; Dr. Steve Austin; Dr. John Baumgardner; Dr. Eugene Chaffin; Dr. Don DeYoung; Dr. D. Russell Humphreys
Sent: Sunday, November 17, 2002 10:13 PM
Subject: Granites

Dear Bob,

Greetings in the Lord's name!

Thanks for your kind words regarding the helium in zircon diffusion experiments. We are grateful to the Lord for the way He has led and guided that project, and indeed all of the RATE research. Of course, we appreciate very much your pioneering work on the helium in zircons, and the radiohalos, which we have acknowledged and have merely built upon.

Please understand at the outset that we do not desire to generate controversy or ill-will toward you with respect to our different views on the origin and formation of granites, and the Po radiohalos in them. We cannot but go where we strongly believe the evidence, both field and laboratory, points, but always in dependence on wisdom and guidance from the Lord through His Word and by prayer.

Bob, you know as well as we do that granites do not contain fossils. Indeed, we would not expect them to contain fossils, because, as granites are igneous rocks, any organic material in the source rocks that melted would have been incinerated. Furthermore, you have carefully read the November Acts and Facts and Impact #353, so you know that I did not claim or write there that we had found and sampled granites containing fossils. Therefore, why do you insist that we provide you with the location details for "fossiliferous granites"? That's not "borrowing the language of Impact #353," but imputing to us something we did not write or claim.

Of course, we can provide you with the precise location details (even GPS coordinates in most instances) of every granite sample we have collected, and you are more than welcome to those details. However, that is not the real issue, is it? You don't agree with our claim that many granites were produced during the Flood by the melting of Flood-deposited, fossiliferous sediments to form molten magmas that then intruded into, and thus cooled surrounded by, other Flood-deposited sediments. According to your model for granite formation, and ours, we should not expect to find fossils in granites, but a real issue here is whether there are fossils in the rocks hosting granites.

There is not the space here for a long technical discussion of all the detailed evidences. Nor does it seem appropriate, given that you must surely be already aware of all the many evidences as presented in the voluminous literature on the subject of granites. However, it would seem you have rejected those impeccable evidences because they have been compiled and presented, in the main, by uniformitarian geologists, and because they conflict with your views based on the Po radiohalos. Nevertheless, you state in your letter that you are seeking to follow the truth, and that you are still learning. Bob, as your friends and your Christian brothers, we have to say, unfortunately very bluntly, that it is wrong for you to go on denying and rejecting the many impeccable observational evidences, that are not tainted with uniformitarianism, but which unequivocally show that many granites were formed from magmas derived by the melting of sediments at temperatures and pressures that destroyed contained fossils. So that you know we are genuine and not generating some smokescreen, let us summarize (all too briefly) the main lines of evidences that convince us (and most other creationist geologists):

  1. Sedimentary basins ought to be places where granite magmas were generated. Copious phase equilibria laboratory studies demonstrate that, at c. 735°C and 5 kbar in the system NaAlSi3O8-KAlSi3O8-SiO2-H2O, the minimum point on the liquidus surface upon further cooling produces crystals in the ratio of approximately quartz 30% orthoclase 35% and albite (plagioclase) 35%, which is the exact normative mineral composition of thousands of granite plutons. In many sedimentary basins the deposited sediments with fossils buried in them can be thousands of meters thick. At depths of 5-10 km, especially in tectonically active zones, the pressures and temperatures can reach 5 kbar and 735°C respectively. These phase equilibria experiments indicate that, under such conditions, the fossiliferous sediments would partially melt to form granitic magmas. Less dense than the surrounding residues, the magmas would then rise through fractures to intrude into the overlying fossiliferous sediments. Subsequent erosion has exposed at the Earth's surface the cooled granite bodies intruded into those fossiliferous sediments.

  2. Regional relationships provide evidence for an igneous origin of granites. In the field it is possible to literally walk over the outcrops from fossiliferous sedimentary rocks through zones of metamorphosed sedimentary rocks, whose mineral constituents reflect the increasing temperatures and pressures of regional metamorphism (these temperatures and pressures being verified by many phase equilibria experiments), to where the felsic minerals in the metasedimentary rocks have melted to form migmatites, and then finally to where at temperatures around 735°C and pressures of 5 kbar and above the whole rock melted to form granite (with the Qz 30% Or 35% Ab 35% composition). One classic example is the Cooma Granodiorite in the centre of the Cooma metamorphic complex in southeastern Australia. Other examples abound, in Scotland, Germany and elsewhere, including the Zoroaster Granite in the Grand Canyon, and the Harney Peak Granite in South Dakota.

  3. Local boundaries argue for an igneous origin of granites. In the field, and in three dimensions within mines (both open cast and underground), the effects on the host rocks of the intrusion of hot granitic magmas can be observed, including veining, stoping and contact metamorphism. The most spectacular examples of the latter are skarns, where granitic magmas have metamorphosed limestones to produce new minerals under high temperature and pressure conditions which have been verified by phase equilibria experiments. And the hot magmatic fluids from the granites have introduced metals into the resultant skarns, such as W at Grassy, King Island, Tasmania and Cu at Grassberg, West Papua, Indonesia. I spent weeks mapping the boundary of the Bathurst Granite west of Sydney for my B.Sc. (Honours) thesis in 1974, noting the veining, stoping and contact metamorphism of the host fossiliferous sedimentary strata in outcrops and in cuttings along the main western railroad from Sydney.

Bob, when we found Po radiohalos alongside U radiohalos in the same biotite flakes in the Cooma Granodiorite we had to rethink what the radiohalos are telling us. We fully agree with you that the Po radiohalos formed exceedingly rapidly, so this granodiorite must have formed rapidly during the Flood. This is exciting evidence that granites intrude and cool rapidly (within days). It is also thus evidence that the U radiohalos formed rapidly, so U decay had to have been accelerated during the Flood year. Your ground-breaking work on Po radiohalos is not being "trashed," but lifted to an exciting new level that still demolishes the uniformitarian timescale. We would also point out that your responses have not been brushed aside and ignored, for they were cited in the comprehensive discussions of radiohalos in chapter 8 of our book, Radioisotopes and the Age of the Earth, published in 2000.

As your friend, Bob, please, you must rethink your position carefully before the Lord. It's time to stop willfully ignoring the evidences for the magmatic origin of granites and the implications. You are wrong to expect us, or anyone else, to show you "fossil-bearing granites." That's nonsense, and you know it! We would welcome you joining us in showing compromising Christians and unbelievers alike that these evidences in God's world powerfully support what God's Word has always plainly taught.

Regards and best wishes,

Yours sincerely in Christ,

Andrew (Snelling)

on behalf of Larry Vardiman, Steve Austin, John Baumgardner, Eugene Chaffin, Don De Young and Russ Humphreys, my co-workers in the RATE Project.


The above page was found at https://www.halos.com/faq-replies/snelling-to-gentry-11-17-2002.htm on November 21, 2024.

© 2004
Earth Science Associates