Freethought & Rationalism Archive

Peez · 02-28-2002, 01:07 PM

Quote:

Kosh:
Damn, I thought we were discussing Flood Geology (or lack of)...

Um, yeah, and that.

Peez

Valentine Pontifex · 02-28-2002, 01:08 PM

<a href="http://www.creationscience.com/onlinebook/HydroplateOverviewa4.html" target="_blank">http://www.creationscience.com/onlinebook/HydroplateOverviewa4.html</a>

Quote:

Frozen Mammoths. Fleshy remains of about 50 elephantlike animals called mammoths, and a few rhinoceroses, have been found frozen and buried in Siberia and Alaska. One mammoth still had identifiable food in its mouth and digestive tract. To reproduce this result, one would have to suddenly push a well-fed elephant (dead or alive) into a very large freezer and turn the thermostat to -150�F. Anything less severe would result in the animal�s internal heat and stomach acids destroying the food. If the animal remained alive for more than a few minutes, one would not expect to find food in its mouth. What could cause such a large and sudden temperature drop? Even if the Sun suddenly stopped shining, the earth�s temperature would not drop rapidly enough to produce such effects. Finally, these giant animals would have to be buried in what was presumably frozen ground�quite a trick.

Even if you take all those statments as true, it is clear that Dr. Brown has never heard of cave-in or avalanches!

ps418 · 02-28-2002, 01:13 PM

Quote:

Originally posted by Bait:
John and Patrick,
I finally found it. The theory of the water below the surface of the mantle. Would you, as a geologists, honestly (with open mind)look at this theory, and tell me what you think. This gentleman seems to have a lot of evidence, but me not being a geologist, I cannot be honestly for or against.

I'm quite familiar with Walt Brown. Brown has a major problem getting the facts straight, and most of the claims he makes are laughably incorrect. I'll give you one example of a claim he made that could have been avoided had ge conducted a 1-minute search of the journals Nature or Science.

Brown stated:
The absence of meteorites in deep sediments is consistent only with a rapid deposition of all the sediments.

But in fact, impact products, impact craters, and even actual meteorites have been found buried in "deep sediments," thus Brown's claim is directly falsified. To take one, well known example. At the K-T boundary, there is a) an 180km wide crater of exactly the right age, b) impact generated products such as melt sperules, microdiamonds, and shocked minerals are found in well over 100 K-T boundary sections in both continental and marine sediments (Glen, W. 1994. The Mass Extinction Debates. Stanford Unoversity Press, p. 9), and c) an actual small chunk of the probable meteorite itself recovered from an ocean core of the K-T boundary (Kyte, F.T. 1998. A meteorite from the Cretaceous/ Tertiary boundary. Nature 396: 237-239).

Though the K-T is probably the best studied impact event, there are many more examples, and still more subsurface examples will surely be discovered in the future. Examples that immediately come to mind are the Ries Crater in Germany (24km), the Siljan Crater in Sweden (55km), the Manicouagan Crater in Quebec (~199km), the Vredefort Crater in South Africa (`140km), and the Sudbury Crater in Ontario (`200km!). These are just a few of the craters that have been well-studied.

Grieve and Robertson (The Terrestrial Cratering Record, Icarus, Vol.38, No.2. 1979, pp.212-229) list dozens of Phanerozoic impact craters. And this represents only the continental record of impact; we can be confident that this represents only a small portion of the total number of impacts which actually occured, since craters are much less likely to be preserved or even located in ocean basins. See also:

Koeberl, C., Reimold, W. U., and Brandt, D., 1996, Red Wing Creek structure, North Dakota: Petrographical and geochemical studies, and confirmation of impact origin. Meteoritics and Planetary Science, v. 31, 335-342.

Koeberl, C., Poag, C.W., Reimold, W.U., and Brandt, D., 1996, Impact origin of Chesapeake Bay structure and the source of North American tektites: Science, v. 271, p. 1263-1266.

Pilkington, M., and Grieve, R. A. F., 1992, The geophysical signature of terrestrial impact craters: Reviews of Geophysics, v. 30, p. 161-181.

Poag, C. W., Powars, Poppe, L. J., and Mixon, R. B., 1994, Meteoroid mayhem in Ole Virginny: Source of the North American tektite strewn field: Geology, v. 22, p. 691-694.

H. B. Sawatzky, Astroblemes in Williston Basin, Bulletin American Association Petroleum Geologists, April 1975, p. 694-710.

J. G. Spray et al., 1998. Evidence for a late Triassic multiple impact event on Earth. Nature 392, 171 - 173

P. M. Vincent, and A. Beauvilain, The Circular Structure of Gweni-Fada, Ennedi: A New Meteorite Impact Crater in Northern Chad, Compt. Rend. Ser. 2, Sect. A. v. 323(1996):12:987-997

There are several additional confirmed examples of impact products such as tectite strewn fields, shocked minerals, and even actual meteorite material in the fossil record, again directly contradicting Brown's assertion. Here are just a few sources describing such finds, again all references that could easily have been found by Brown had he looked:

P. Claeys. 1994. Microtektite-like Impact Glass associated with the Fransnian-Famennian Boundary Mass Extinction, Earth Planetary Science Letters. 122:3-4 , p 303-315.

Clymer, A. K., D. M. Bice, A. Montanari. 1995. Shocked quartz in the Late Eocene: bolide impact evidence from Massignano, Italy. 4th International Workshop on Impact and Evolution of Planet Earth, pp. 60.

B.P.Glass and C. Koeberl. 1999. ODP Hole 689B spherules and upper Eocene microtektite and clinopyroxene-bearing spherule strewn fields. Meteoritics & Planetary Science 34.

Henderson, E. P., and Cooke, C. W., 1942. The Sardis (Georgia) meteorite. Proc. U.S. National Museum, 92:141-150.

Izett, G. A., Cobban, W. A., Obradovich, J. D., and Kunk, M. J., 1993, The Manson impact structure: 40Ar-39Ar age and its distal impact ejecta in the Pierre shale in southeastern South Dakota: Science, v. 262, p. 729-732.

Kerr, Richard A., 1996. A piece of the dinosaur killer found? Science, v. 271, 29 March 1996, p. 1806.

Koeberl, C., and Shirey, S. B., 1993, Detection of a meteoritic component in Ivory Coast tektites with rhenium-osmium isotopes: Science, v. 261, p. 595-598.

Koeberl, C., Masaitis, V. L., Langenhorst, F., St�ffler, D., Schrauder, M., Lengauer, C., Gilmour, I., and Hough, R. M., 1995, Diamonds from the Popigai impact structure, Russia: Lunar and Planetary Science, v. XXVI, p. 777-778.

Leroux, H., Reimold, W. U., and Doukhan, J. C., 1994, A T.E.M. investigation of shock metamorphism in quartz from the Vredefort dome, South Africa: Tectonophysics, v. 230, p. 223-239.

Leroux, H., J. E. Warme, and J. C. Doukhan. 1995. Shocked quartz in the Alamo breccia, southern Nevada: evidence for a Devonian impact event. Geology. vol. 23, pp. 1003-1006.

Nystr�m, J. O., Lindstr�m, M., and Wickman, F. S. 1988. Discovery of a second Ordovician meteorite using chromite as a tracer. Nature, 336:572-574.

Schmitz, B., Lindstrom, M., Asaro, F., and Tassinari, M.. 1996. Geochemistry of meteorite-rich marine limestone strata and fossil meteorites from the Lower Ordovician at Kinnekulle, Sweden. Earth and Planetary Science Letters. volume 145, pp. 31-48.

P. Thorslund, F. E. Wickman and J. O. Nystrom, 1984. The Ordovician Chondrite from Brunflo, Central Sweden, I, General Description and Primary Minerals, Lithos, 17, p. 87.

W. Wei, 1995. How Many Impact-Generated Microspherule Layers in the Upper Eocene? Palaeogeography, Palaeoclimatology, Palaeoecology. 114:1, pp. 101-110.

Yudin, I. A., 1971. Relict structures of stony meteorites in a Mesozoic formation of the central Urals. Meteoritics, 6: 99-103.

Impact products have also now been found in very old sediments of Proterozoic and Archaean age.

Shoemaker, E.M., Shoemaker, C.S.. The Proterozoic impact record of Australia. AGSO J. Aust. Geol. Geophys. 16 (1996) 379-398.

Glikson, A.Y., 1999. Oceanic mega-impacts and crustal evolution. Geology, 27:387-341.

Byerly, G. R., Lowe, D. R., 1994. Spinels from Archaean impact spherules: Geochim. et Cosmochim. Acta, 58:3469-3486.

Shukolayukov, A., Kyte, F.T., Lugmair, G.W. and Lowe, D.R., 1998. The oldest impact deposits on Earth - first confirmation of an extraterrestrial component (abstract), Cambridge meeting on Impacts and the Early Earth.

Simonson, B.M., 1992. Geological evidence for an early Precambrian microtektite strewn field in the Hamersley Basin of Western Australia. Geol. Soc. Am. Bull., 104, 829-839.

Simonson, B.M. & Hassler, S.W., 1997. Revised correlations in the early Precambrian Hamersley Basin based on a horizon of resedimented impact spherules. Aust. J. Earth Sci., 44, 37-48.

Discovery of a layer of probable impact melt spherules in the Late Archaean Jeerinah Formation, Fortescue Group, Western Australia. B. M. Simonson, D. Davies and S. W. Hassler. Australian Journal of Earth Sciences 47 (2), 315-325. Geological Society of Australia.

Glikson, A.Y., 1996, Mega-impacts and mantle melting episodes: tests of possible correlations. Australian Geological Survey Organisation Journal,16/4:587-608.

So in fact one could safely abandon Noah's flood as an explanation for the geologic record on the basis of impact phenomena alone, since there is no known mechanism that could concentrate so many bolide impacts into the mere weeks or months of the flood. And even if there were such a mechanism, Noah and family could hardly surivive such an interval of heavy bombardment.

These types of basic errors and false statements of fact pop up again and again in Brown's writing. This is just the tip of the iceberg. Is there some part of Brown's 'theory' in particular that you'd like to discuss?

Patrick

When I looked at Brown's refs, I found there dated from the 1950's.

Now granted, we ALL make errors. But errors of this type are simply baffling, and leads one to believe that Brown is actually lying.

John Solum · 02-28-2002, 01:14 PM

You quote me as follows:

Quote:

"A little on another topic on geology, how long the organisms that existed were single-celled. So, over a comparitively short period of time (120 million years is 3.8% of 3.15 billion years) earth's fauna diversifed into a variety of multicellular organisms as well as single-celled organisms."

A word of caution. If you put something in quotation marks, it should be an exact quote. Here's what I said:

"Life first appeared ~3.8 billion years ago, and from that time until ~650 million years ago (a duration of 3.15 billion years) the organisms that existed were single-celled. So, over a comparitively short period of time (120 million years is 3.8% of 3.15 billion years) earth's fauna diversifed into a variety of multicellular organisms as well as single-celled organisms."

In order to avoid confusion, please be more careful with your quotations in the future.

Quote:

So there are two questions at this point: 1. Assuming you are correct that pre-cambrian had single celled organisms, 1. were they all the same in structure (make up...the same type of organism)? and 2. did they come from the same "pool/area/location"? Why is this relevent? Because if they did not come from the same location, and if they were not made up of the same materials (chemicals/chromosomes), then life could not have come from only one source. In order to have only one common ancestor, you have to have that first one, from which all else comes from. It all had to of started in one pool, one location, one microorganism. so where exactly was this pool located, and what exactly was the organism that started it all? Otherwise, the theory fails.

We're moving away from the Cambrian explosion here. There are a variety of single-celled organisms from the Precambrian, and the fossils are widespread. The first to appear are prokaryotes followed by eukaryotes. Here are two links on Precambrian microfossils:

<a href="http://www.ucmp.berkeley.edu/fosrec/Lipps1.html" target="_blank">http://www.ucmp.berkeley.edu/fosrec/Lipps1.html</a>

<a href="http://www.ucmp.berkeley.edu/bacteria/bacteriafr.html" target="_blank">http://www.ucmp.berkeley.edu/bacteria/bacteriafr.html</a>

I doubt paleontologists will ever be able to point to a particular outcrop and say "life began here", but that doesn't invalidate the theory of evolution. Peez has explained this better than I could (Peez also appears to be pretty good at catching my spelling errors). We may never know how and where life first arose, but that doesn't affect the theory of evolution. For example, how and where life arose plays no part in the Cambrian explosion; how life arose plays no part in the evolution of amphibians or reptiles or mammals. The study of how life originated is separate from (but related to) the study of what happened once life appeared (i.e., the theory of evolution).

Bait · 02-28-2002, 01:22 PM

Kosh,
Me too...but as it was pointed out, one relates to the other. (Remember, I kept saying I didn't want to get into a flood debate...but???)

Honest, I did not know how valid the Brown theory is, was, etc...I saw it presented once (actually on TV, part of the "flood series") which is why I asked for a general review to debunk...etc. I think John (or someone) asked me where that theory is (I had mentioned it elsewhere) The phylum, etc. came from the Cambrian period...an offshoot of the debate Oolon and I were in. A couple of people on this list was not on the previous...so they ar ekind of coming into the middle. The other theory I mentioned related is a sudden plate movement, which displaces water from the oceans (like a giant tsunami)that went (washed) worldwide...both purported theories of how the flood could have happened. The cambrian bit offshot, partly because it occurred before the flood could have.
Ron

Quote:

Originally posted by Kosh:


Damn, I thought we were discussing Flood
Geology (or lack of)...

Bait · 02-28-2002, 01:27 PM

Thanks Patrick, that's what I was looking for.
Ron

Quote:

Originally posted by ps418:
Bait:
Second question:
has it been estimated that the cores of the ice caps, have been around? Were the polar regions always ice? Now I'm on shaky ground here, and I'm really only looking for the evidence to dispute this, but I read that the Ice cores of the polar regions have a maximum of about 14,000 feet of ice. An airplane was excavated (I read) that had been exposed to the climate for 48 years, and it was buried 262 feet in ice (which equals to 5.45 feet per year). The calculations I read about estimates then the ice caps at a little over 2500 years old. Geologically then, is this a true estimate?

No, like other YEC attempts to date various geologic features of the earth, this estimate is based on a complete lack of knowledge about how ice sheets are dated. In particular, it assumes that a) ice sheets can be dated by simple thickness, and that b) there is a linear relationship between thickness and age.

Both assumptions are false.

First ice sheets are not dated by thickness, but by annual layer counting, by isotopic correlation with indedependently-datable paleoclimate records such as tree ring series and varved deposits, and other methods.

Second, annual layers become thinnner with depth in the ice, because of the greater and greater weight of overburden (and because the ice flows outward under the weight - like a rubber band becoming thinner as you stretch it). Last year's snow might be several feet thick, whereas layers from, say, 20,000 years ago mght be an inch thick or somewhere in that neighborhood. The ice at the firn/ice boundary may be a century or more old.

As an example of how ice layers thin with age, Cronin (Principles of Paleoclimatology, p. 433) shows several ice core sections with well-defined annual layers from 82, 105, 120, and 135 meters below surface in a glacier in south america. Over that thickness of 53m, average annual layer thickness shrinks from 16.9, to 5.0, to 3.0, and 1.7 cm, respectively.

Even if we ignored layer counting and other methods and just took the YEC estimate at face value, adding a correction for ice compaction with depth, even then you'd get an age 'estimate' that is far too long to fit into the YEC timescale.

Also, as Richard Alley points out in his book The Two-Mile Time Machine, the planes of the Lost Squadron landed near the coast, in an area of extremely high snow accumulation rates, far higher than the accumulation rates near the center of the ice sheet where the GISP, GRIP, and GISP2 cores were taken.

Patrick

ps418 · 02-28-2002, 01:32 PM

I agree with Faded_Glory about Brown's suggestion that chalk is an inorganic deposit. Below is a slightly modified post I made to another forum a long time ago.

Brown made some statements on his page that I think speak volumes about his attention to detail. For instance, he says the Cretaceous chalk cliffs are inorganic (such as those in Dover). Just so everyone knows Im not making this up, his exact words are:

"Similarly, waters escaping from under the western edge of the European hydroplate may have dumped the soft, fine-grained type of limestone known as chalk. Most famous are the exposed layers in England�s White Cliffs of Dover and France�s coast of Normandy. While chalk contains **a few organic remains, most of it is inorganic**"

He probably couldnt have picked a worse example. In fact, these chalks are not only "organic," they consist almost entirely of fossils (mainly forams and coccoliths). Also present are whole shells and fragments of bivalves, ostracods, ammonites, echonoids, etc. They've been studied extensively.

The only sense in which Brown could be right is that all limestones are originally porous (30-70% porosity or so), but the pore spaces are filled in by the precipitation of aragonite and calcite 'cements' after deposition, forming hard rock from loose deposits. But this isnt what Brown is arguing.

The chalk deposits also have numerous firmgrounds and hardgrounds, proving that there were numerous breaks in deposition, but thats another post.

But please don't take my word for it. Judge Brown's accuracy for yourself. Here's a magnified thin section photo of the Cretaceous "Middle Chalk" from England:

The circles are coccolithophores and the little elongate thing in the bottom right is a foram shell.

The following picture is a thin section photo of some Cretaceous foraminiferal chalk in Mississippi:

And a Cretaceous chalk from Texas:

See also:

H�kansson. E., Bromley. R., and Perch-Nielson. K., 1974, Maastrichtian chalk of north-west Europe � a pelagic shelf sediment. Pelagic sediments: On land and under water. PP 211-23, Spec. Pub. Int. Assoc. Sed., No. 1.

Gale, A.S. 1996. Correlation and sequence stratigraphy of the Turonian Chalk of southern England. Sequence stratigraphy in the United Kingdom. In: Hesselbo, S.P. and Parkinson, D.N.(eds.) , Sequence Stratigraphy in British Geology. Geological Society, London, Special Publication 103, 177-195.

Regarding another one of Brown's claims about limestone, Cliff Cuffey highlights another one of Brown's false claims:

Cuffey again, taking Walt Brown to task:

"Concerning the origin of limestone grains, Brown (1996, p. 188) stated that "...few are ground-up sea-shells or corals..." This statement is factually wrong. I'm certain that all of us can think of a wide variety of limestones from throughout the Phanerozoic that are primarily composed of skeletal grains. In fact, the New Orleans Cotton Exchange, and some other New Orleans buildings, are constructed primarily from the Salem Limestone (Mississippian), an endothyrid foram - bryozoan grainstone from southern Indiana. The Burlington Limestone (Mississipp ian) and its equivalents throughout central and western North America are a vast blanket of crinoidal grainstones and packstones (Ausich, 1997). Such regional encrinites are common from the Ordovician through the Jurassic (Ausich, 1997, p. 513). Carbonate sediments composed primarily of skeletal grains are being deposited today on platforms and ramps such as southern Florida (Sellwood, 1986, p. 307), the Bahamas (Bathurst, 1975, p. 104, 108-121), and the Persian Gulf (Hughes Clarke & Keij, 1973; Wagner & van der Togt, 1973; Bathurst, 1975, p. 181-185). Such sediments accumulate in situ both in reef (James, 1983) and non-reef (Wilson & Jordan, 1983, p. 307-316) environments. Again, we can make the logical connection between process and result both in modern environments and the rock record."

<a href="http://www.gcssepm.org/special/evolution.htm" target="_blank">Evolution, Scientific Creation, Uniformitarian Geology, and Flood Geology </a>

Patrick

Bait · 02-28-2002, 01:42 PM

Hi Peez,
I haven't been meaning to not answer you. Actually, that is what was said to me, which is what I dispute. I do have views where I believe the origin of man not being created as the animals were (as in the Biblical account), but I've admitted up front they were my views. That is a dispute that would go in circles because it requires faith over scientic "evidence", and I'm not trying to convert anyone. I admit that there seems to be scientific evidence against the view of men being created by God...notice I said "seems"...because there is no "hard" evidence, and I choose faith. If you do not...fine. As to the "other" animals...my point was that we...and the animals did not have a (one) common ancestor, rather evidence points that the ancestors should be more properly be ancestors. The cambrian and pre-cambrian era's give evidence of this, which you (and others) confirmed. Now we can go on and debate on geological "flood" evidence/non evidences, or go on and debate whether there is any real evidence of single or multi celled organism's evolving into whatever creatures.
Bests,
Ron

Quote:

Originally posted by Peez:
Nobody thinks that mammals "come from plants." Mammals and plants share a common ancestor.

Peez[/QB]

ps418 · 02-28-2002, 01:43 PM

Quote:

Originally posted by Bait:
Thanks Patrick, that's what I was looking for.
Ron

My pleasure Ron.

While I'm posting, there's one more thing I want to point out.

One cannot consistently argue both that a) the fossil record is inconsistent with evolution, AND that the fossil record was deposited by Noah's flood.

The reason is that if the fossil record was deposited by a 1-year flood, it can tell us nothing about life changing or not changing over time -- it can only tell us about the life that existed on earth immediately prior to the flood. Thus, on the flood view, there never was a Cambrian explosion and so on, and earlier organisms, if they existed, were not preserved.

Surprisingly, many YEC authors do not seem aware of this simple, logical inconsistency.

Patrick

John Solum · 02-28-2002, 01:53 PM

Quote:

Originally posted by Bait:
John and Patrick,
It's called the "Hydroplate theory" by Dr. walter Brown.: <a href="http://www.creationscience.com/onlinebook/index.html" target="_blank">http://www.creationscience.com/onlinebook/index.html</a>
Go to part II “fountains of the deep”

I'm glad you found the site you were looking for, and I'm familiar with Brown. Here's a specific example of a flaw in his understanding of fault motion in general and the San Andreas fault in particular:

<a href="http://www-personal.umich.edu/~jsolum/yec/earthquakes.html" target="_blank">http://www-personal.umich.edu/~jsolum/yec/earthquakes.html</a>

LordValentine made some excellent points about Brown's lack of understanding of paleomagnetism, and I'll expand on that a bit. LordValentine is correct that magnetic reversals are well-known in terrestrial rocks (there's a branch of geology known as paleomagnetism that deals with the "fossil" magnetism of rocks - not just reversals, but also the inclination of the paleomagnetism, which can be used to determine where continents where in the past). The recognition of magnetic "stripes" that are "mirrored" (for lack of a better word) about ridges is one of the pieces of evidence that lead to the recognition of sea floor spreading, but that's by no means the only evidence we have of magnetic reversals. LordValentine's description of how magnetism of the seafloor is measured from ships is very good.

LordValentine also mentions something called magnetostratigraphy. The duration and age of the periods of normal and reversed polarity of the earth's magnetic field have been determined by studying good exposures of rocks that can also be radiometrically dated. In other words the pattern of magnetic polarity over time has been established. So if you measure the polarities in samples of an unknown age you can match the pattern of normal and reversed polarites in your samples to the pattern that's already been established and so you can determine how old your rocks are.

As patrick and faded_glory have pointed out Brown's claim that chalk is inorganic is just plain silly.

In general, I think he has an unreasonable expectation about what the natural world should look like. He expects faults (like the San Andreas) and fracture zones at ridges and magnetic "stripes" to be perfetly straight; if they're not he says it's a problem for conventional geology. It's unreasonable to expect nature to be "constructed" to machine-shop precision.

His claim that thrust faults are physically impossible is also wrong. His model is flawed, but worse than that, there are hundreds of active thrust faults all over the world.

Brown's claim:

<a href="http://www.creationscience.com/onlinebook/TechnicalNotes11.html#1024325" target="_blank">http://www.creationscience.com/onlinebook/TechnicalNotes11.html#1024325</a>

A section from my FAQ on thrust faults dealing with that claim:

<a href="http://www.talkorigins.org/faqs/lewis/#mechanics" target="_blank">http://www.talkorigins.org/faqs/lewis/#mechanics</a>

and

<a href="http://www.talkorigins.org/faqs/lewis/#strength" target="_blank">http://www.talkorigins.org/faqs/lewis/#strength</a>

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02-28-2002, 01:32 PM	#47
ps418 Veteran Member Join Date: Mar 2001 Location: Louisville, KY, USA Posts: 1,840	I agree with Faded_Glory about Brown's suggestion that chalk is an inorganic deposit. Below is a slightly modified post I made to another forum a long time ago. Brown made some statements on his page that I think speak volumes about his attention to detail. For instance, he says the Cretaceous chalk cliffs are inorganic (such as those in Dover). Just so everyone knows Im not making this up, his exact words are: "Similarly, waters escaping from under the western edge of the European hydroplate may have dumped the soft, fine-grained type of limestone known as chalk. Most famous are the exposed layers in England�s White Cliffs of Dover and France�s coast of Normandy. While chalk contains a few organic remains, most of it is inorganic" He probably couldnt have picked a worse example. In fact, these chalks are not only "organic," they consist almost entirely of fossils (mainly forams and coccoliths). Also present are whole shells and fragments of bivalves, ostracods, ammonites, echonoids, etc. They've been studied extensively. The only sense in which Brown could be right is that all limestones are originally porous (30-70% porosity or so), but the pore spaces are filled in by the precipitation of aragonite and calcite 'cements' after deposition, forming hard rock from loose deposits. But this isnt what Brown is arguing. The chalk deposits also have numerous firmgrounds and hardgrounds, proving that there were numerous breaks in deposition, but thats another post. But please don't take my word for it. Judge Brown's accuracy for yourself. Here's a magnified thin section photo of the Cretaceous "Middle Chalk" from England: The circles are coccolithophores and the little elongate thing in the bottom right is a foram shell. The following picture is a thin section photo of some Cretaceous foraminiferal chalk in Mississippi: And a Cretaceous chalk from Texas: See also: H�kansson. E., Bromley. R., and Perch-Nielson. K., 1974, Maastrichtian chalk of north-west Europe � a pelagic shelf sediment. Pelagic sediments: On land and under water. PP 211-23, Spec. Pub. Int. Assoc. Sed., No. 1. Gale, A.S. 1996. Correlation and sequence stratigraphy of the Turonian Chalk of southern England. Sequence stratigraphy in the United Kingdom. In: Hesselbo, S.P. and Parkinson, D.N.(eds.) , Sequence Stratigraphy in British Geology. Geological Society, London, Special Publication 103, 177-195. Regarding another one of Brown's claims about limestone, Cliff Cuffey highlights another one of Brown's false claims: Cuffey again, taking Walt Brown to task: "Concerning the origin of limestone grains, Brown (1996, p. 188) stated that "...few are ground-up sea-shells or corals..." This statement is factually wrong. I'm certain that all of us can think of a wide variety of limestones from throughout the Phanerozoic that are primarily composed of skeletal grains. In fact, the New Orleans Cotton Exchange, and some other New Orleans buildings, are constructed primarily from the Salem Limestone (Mississippian), an endothyrid foram - bryozoan grainstone from southern Indiana. The Burlington Limestone (Mississipp ian) and its equivalents throughout central and western North America are a vast blanket of crinoidal grainstones and packstones (Ausich, 1997). Such regional encrinites are common from the Ordovician through the Jurassic (Ausich, 1997, p. 513). Carbonate sediments composed primarily of skeletal grains are being deposited today on platforms and ramps such as southern Florida (Sellwood, 1986, p. 307), the Bahamas (Bathurst, 1975, p. 104, 108-121), and the Persian Gulf (Hughes Clarke & Keij, 1973; Wagner & van der Togt, 1973; Bathurst, 1975, p. 181-185). Such sediments accumulate in situ both in reef (James, 1983) and non-reef (Wilson & Jordan, 1983, p. 307-316) environments. Again, we can make the logical connection between process and result both in modern environments and the rock record." <a href="http://www.gcssepm.org/special/evolution.htm" target="_blank">Evolution, Scientific Creation, Uniformitarian Geology, and Flood Geology </a> Patrick

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