Posted on 09/02/2003 6:39:19 AM PDT by bedolido
Maybe if they do enough research they can make it disappear altogether? LOL!
WRONG THREAD!!!
;-)
You are too rash. This is a much more complex issue than you realize. You just cannot understand, with a layman's simple-minded grasp of a complex interrelationship.
Because contrary to your assertion, there is indeed abundant evidence indicating that that's what happened.
In the narrow band of the KT (Cretaceous/Tertiary) boundary in the geologic column, dating to 65 million years ago, which separates the era of the dinosaurs from more modern strata in which dinosaur fossils are never found, there is a huge spike in the amounts of the element Iridium, which is normally quite rare in the Earth's crust:
The only known sources of such high levels of Iridium are either materials *deep* in the Earth's mantle, far below the crust, or carbonaceous chondrite meteorites.
That alone would point undeniably towards either a large meteorite strike which splattered its material around the Earth 65 million years ago, or some massive volcanic event originating very deep in the Earth 65 million years ago which spewed deep-mantle material around the planet.
The rest of the evidence settles the matter in favor of the meteorite scenario.
The amount of Iridium in the KT boundary was calculated to be the amount that one would expect from a carbonaceous chondrite meteor about 10 kilometers (6 miles) in diameter.
Later, a 65-million year old meteorite crater was discovered straddling the coast of the Yucatan peninsula in Mexico, 100 miles in diameter and over a mile deep. It was not previously recognized because it had been buried in 65 million years of subsequent sediment, but it was found via seismic scans and gravitational mass scans while looking for oil:
It has been named the Chicxulub crater. Calculations of the size of meteorite which would produce a crater of this size and type resulted in an answer of... 10 kilometers, the same size as a meteorite which would be expected to produce the amount of Iridium found in the KT boundary.
This alone (same size, same timeframe) is very strong evidence that this is the crater produced by the meteorite which produced the Iridium found in the KT boundary. But there's more.
Also in the KT boundary are small glass spheres known as "tektites":
These are formed by meteorite impacts when rock from the impact site is vaporized, and then spreads from the site and condenses back into solid rock in a manner similar to the formation of hailstones from clouds of water vapor. These then fall to the ground (again like hail) littering the ground. Volcanoes can also produce tektites, but only smaller volcanic eruptions, which do not spread the tektites very far. The tektites in the KT layer are found all over the world (in varying amounts, more on that later), effectively ruling out a volcanic origin and again pointing to a large meteorite impact, which would indeed spread tektites worldwide.
Furthermore, the tektites in the KT layer are of a type more accurately known as basaltic spherules, which are not of the type one would expect from a volcanic origin, but instead are consistent with production via a meteorite impact on oceanic crust -- which again is the site of the 65 million year old Chicxulub crater.
Moreover, characteristic elemental ratios can distinguish between materials of an earthly origin (obviously the case for the results of volcanic action) versus extraterrestrial origins (i.e. meteorites). The ratios of platinum-group elements, as well as the relative abundances of ruthenium, rhodium and iridium in the KT boundary, all match the "fingerprint" of meteoritic origin.
And there's more. Both volcanic activity and meteorite strikes can produce characteristic high-pressure, high-temperature crystalline materials such as "shocked quartz". However, each type of production results in crystals that are detectably different in several ways. The shocked quartz (and other) crystals found in the KT boundary match only the type expected from a meteoritic origin:
Even worse for the volcanic scenario, another form of modified quartz called stishovite has been found in the KT layer, and the pressures required to form this type of quartz are far greater than those produced by any volcanic process -- only a major meteorite strike qualifies.
Also in the KT layer is a huge amount of soot (7000 teragrams) which indicates that a large portion of the Cretaceous forests burned at the time of the KT meteorite impact, as would be expected for the impact fireball and rain of molten debris which would splatter around most of the planet in the event of an impact of that size. And yes, the nature of the soot (isotopic makeup, chemical ratios, etc.) allow the safe conclusion that it was extant vegetation which burned at the time, and not coals or fossil fuels, etc., and not ash from a volcanic eruption. Here's an oceanic core sample showing the soot layer, taken 350 miles east of northern Florida:
Finally, the thickness and nature and distribution of the various types of debris found in the KT boundary at various locations around the world are very consistent with a scenario of a 10km meteorite striking on the Yucatan peninsula at a shallow angle from a southeasterly direction. For example, direct debris is thicker nearer the Yucatan as compared to locations farther away around the Earth, there is a heavier "stripe" of debris arrowing norhwesterly across the North American continent originating from "ground zero" in the Yucatan, etc. Furthermore, the pattern of tsunami debris around the Gulf of Mexico and the Atlantic Ocean in the KT boundary matches the direction, distances, and amounts one would expect for a 10km meteorite strike in the Yucatan 65 million years ago, as in this layer of breccia (jumbled, shattered rock) found on the KT layer in Falls County Texas, due to massive tsunamis carrying debris a hundred miles inland:
The rust-colored layer which the pick is resting upon is the tsunami debris, and above that is a thin layer of finely powdered Iridium-rich meteorite strike debris, which settled as dust on the material left behind by the tsunamis.
Furthermore, there is a striking difference in the fossils found below the KT boundary versus above. Over 90% of the species which have fossils appearing below the KT boundary (including the dinosaurs and many others) vanish at the KT boundary. Immediately above, the KT boundary is only a select few of the species found below the KT boundary, then as you look higher above the KT boundary life is seen to be slowly springing back from the mass extinction.
I'm sorry, what's that you were saying about there being "no evidence" for a meteorite strike?
when in fact, the Biblical Flood of Noah offers a much more compelling answer as to why they died out?
As soon as you can figure out how most of the Earth's forests can burn during a worldwide flood, and how other signs of intense heat (tektites, shocked quartz, etc.) are consistent with a flood, and how a flood would produce Iridium and platinum levels only consistent with an extraterrestrial origin, do let us know. Meanwhile, a global flood would leave worldwide evidence as obvious and striking as that left by the Chicxulub meteorite, but no such evidence exists.
Please see post #115
What about the iridium layer?
by Jonathan Sarfati, Ph.D.
Great impact theory
The current ‘glamour’ theory was proposed by the geologist Walter Alvarez in about 1980, that a meteor strike 66.4 million years ago caused dramatic climatic changes much like ‘nuclear winter’. This caused the extinction of the dinosaurs and many other species. His evidence was his discovery of an allegedly world-wide layer of clay with a high iridium content. His father Luis, who won the Nobel Prize in Physics in 1968 for work on subatomic particles, helped him publicize the theory. It is now accepted as ‘proven fact’ in many circles, and popularized in ‘documentaries’ such as Walking with Dinosaurs.
Problems with the ‘great impact’ theory
The secular book The Great Dinosaur Extinction Controversy exposes the way that the meteor explanation for the dinosaur extinction has become a new dogma that has way outstripped the evidence (see review by Carl Wieland in CENTJ 12(2):154–158, 1998). Some of the reasons are:
The extinction was not that sudden (using evolutionary/long age interpretations of the geological record). But the spread in the geological record makes sense if much of the sedimentary deposits were formed in Noah’s Flood.
Light-sensitive species survived.
Extinctions don’t correlate with crater dates.
Modern volcanic eruptions don’t cause global extinction patterns, even if they cause a temporary temperature drop.
The iridium enrichment, supposedly a key proof of meteor impact, is not nearly as clearly defined as claimed.
Drill cores of the apparent ‘smoking gun’ crater on the Yucatán peninsula in south-east Mexico do not support the idea that it is an impact crater.
It seems that some scientists didn’t speak out against the idea for fear of undermining the ‘nuclear winter’ idea, and being grouped with ‘nuclear warmongers’.
The overview article by meteorologist Mike Oard, ‘The extinction of the Dinosaurs’ (CENTJ 11(2):137–154, 1997; download PDF file) explains many features of dinosaur fossils that are consistent with a flood, and dinosaur tracks consistent with fleeing from encroaching flood waters. Oard points out that iridium enrichment can be caused by massive volcanism, as many evolutionists agree. This would certainly have been a feature of the Flood year, associated with the breaking up of the ‘fountains of the great deep’ (Genesis 7:11). However, Oard agrees that the largest iridium anomalies were caused by meteorites striking during the Flood:
‘Iridium-rich clay falling from the atmosphere would accumulate only during temporary lulls in the Flood.’
This explains the fact that so-called spikes are really composed of multiple spikes or are spread over a wider layer of sediment. John Woodmorappe has pointed out:
‘there are now over 30 iridium “horizons” in the Phanerozoic record. These can be explained by a slowdown in sedimentation rate as iridium rained from the sky (whether from a terrestrial, or an extraterrestrial source). They pose no problem for the Flood at all.’
That is, the iridium layers mark lulls in the sedimentation rate during the Flood, the iridium ‘rain’ itself being more-or-less continuous during the Flood.
K/T (Cretaceous/Tertiary) boundary Oard also pointed out that the K/T boundary supposedly marking the end of the dinosaur age is most likely not synchronous around the world, and is not defined coherently. Very few dinosaur fossils are actually found near this boundary. Sometimes the argument becomes very circular. For example, the end of the dinosaur era is supposed to be clearly marked in the geological column by the K/T boundary, but in many localities the K/T boundary is defined by the highest dinosaur fossil. Or else the Alvarez theory is supported by the iridium spike in the K/T boundary, but in some localities the K/T boundary is defined by the iridium spike.
Conclusion
The Bible provides the only coherent framework within which we can properly interpret history, including that of the dinosaurs. Other theories are doomed to failure, even the glamorous ‘deep impact’ theory, because all circumstantial evidence counts for nothing if it ignores the only eye-witness account we have of Creation and the Flood — the Bible.
Did you even read post #115? Your cut-and-paste utterly fails to deal with the majority of it, and disingenuously waffles around the key points of the one thing it does address. Care to try again, or would you like to concede you have no proper rebuttal?
The extinction was not that sudden (using evolutionary/long age interpretations of the geological record).
There were climate changes prior to the end of the Cretaceous which had some species on the decline. But the KT extinction most certainly was "sudden", and no amount of creationist hand-waving changes that. Dinosaurs -- vanished. Ammonites of all species: Gone. Over 75% of the species present immediately before the KT impact vanish at the KT boundary, both land and sea.
But the spread in the geological record makes sense if much of the sedimentary deposits were formed in Noah’s Flood.
There is no such "spread" in the geologic record of the kind Sarfati is trying to vaguely imply.
Light-sensitive species survived.
Which is relevant to *what*, exactly?
Extinctions don’t correlate with crater dates.
This is quite simply disingenuous. Yes, they do.
Modern volcanic eruptions don’t cause global extinction patterns, even if they cause a temporary temperature drop.
They don't cause worldwide fires and countless cubic miles of atmospheric debris, either, so this is a straw man distraction from the actual point.
The iridium enrichment, supposedly a key proof of meteor impact, is not nearly as clearly defined as claimed.
Looks pretty "clearly defined" to me:
Drill cores of the apparent ‘smoking gun’ crater on the Yucatán peninsula in south-east Mexico do not support the idea that it is an impact crater.
What has Sarfati been smoking? Yes, the drill cores most certainly *do* "support the idea that it is an impact crater". For just one study of countless:
SHOCK METAMORPHISM OF IMPACTITE LITHOLOGIES OF THE ICDP CHICXULUB DRILL CORE YAX-1Warning: Creationist websites are often less than honest.
R. T. Schmitt, A. Wittmann and D. Stöffler Institute of Mineralogy, Museum of Natural History, Humboldt-University of Berlin, Invalidenstr. 43, D-10115 Berlin, Germany (ralf-thomas.schmitt@rz.hu-berlin.de/Fax: +49-30-20938565)The ICDP Chicxulub drillcore YAX-1 exposes about 100 m of allochthonus polymict impact breccias in a depth of 794.63 to 894.94 m [1]. In this preliminary study we focus on the shock effects and shock metamorphism of these impactites. 26 thin sec-tions of the impactites from YAX-1 have been investigated for shock effects by optical microscopy and REM. The shock classification of the components uses the method de-scribed in [2]. Within all 6 impactite units (794.63 - 894.94 m, see [1]) more or less the same shock features within silicate fragments are: (1) Quartz and feldspar fragments of shock stage I display decorated PDF’s. (2) Unaltered fragments of shock stages II (diaplectic glass) and III (normal mineral glass) are lacking since they are completely recrystallized. Therefore ballen quartz textures and checkerboard plagioclase are rel-atively frequent. (3) Melt fragments of shock stage IV are the dominating component within the suevite. In most of the units at least two different types of silicate melt fragments occur. They are crystallized, in many cases indicate a possible exsolution of carbonate melts (droplet-like and/or dike-like shapes of calcite) and contain shocked and recrystallized crystalline fragments. In comparison to suevite deposits of smaller impact craters (e.g. Nördlinger Ries [3,4]) the content of melt fragments within the Chicxulub suevites is much higher. The intense (re)crystallization of fragments and melt fragments indicate very high post-depositional temperatures and a strong post impact hydrothermal activity which is typical for melt-rich impactite units [5].
References: [1] Stöffler D. et al. (2003), this volume. [2] Stöffler D. (1971) JGR, 76, 5541-5551. [3] Stöffler et al. (1977) Geologica Bavarica, 77, 163-189. [4] Engelhardt v. W. (1997) MAPS, 32, 545-554. [5] Grieve R. F. A. et al. (1996) MAPS, 31, 6-35.
Oard points out that iridium enrichment can be caused by massive volcanism, as many evolutionists agree.
But *not* the kind of Iridium enrichment found in the KT layer, for reasons I've already explained.
‘there are now over 30 iridium “horizons” in the Phanerozoic record.
Minor ones, because as already discussed volcanic eruptions can produce small "bumps" in Iridium levels. But again, *not* ones as large as, nor of the type of, the KT spike. Straw man again.
These can be explained by a slowdown in sedimentation rate as iridium rained from the sky (whether from a terrestrial, or an extraterrestrial source). They pose no problem for the Flood at all.’
Actually, it does, to a great degree, for too many reasons to get into here.
K/T (Cretaceous/Tertiary) boundary Oard also pointed out that the K/T boundary supposedly marking the end of the dinosaur age is most likely not synchronous around the world, and is not defined coherently.
Oard is, quite simply, wrong. Or dishonest. And neither option inspires confidence.
Very few dinosaur fossils are actually found near this boundary.
"Very few" dinosaur fossils are found anywhere -- fossilization of any sort is a rare event, most animal bodies do not get fossilized. This is yet another straw man.
Sometimes the argument becomes very circular. For example, the end of the dinosaur era is supposed to be clearly marked in the geological column by the K/T boundary,
Disingenuous description -- that's not how the KT boundary is located.
but in many localities the K/T boundary is defined by the highest dinosaur fossil.
Here Sarfati admits that no dinosaur fossils are found anywhere above the KT boundary, but he tries to make it sound like a problem for standard geology. On the contrary, it's a problem for Sarfati's "alternate" scenario.
Or else the Alvarez theory is supported by the iridium spike in the K/T boundary, but in some localities the K/T boundary is defined by the iridium spike.
It's only Sarfati who is being circular here. The KT boundary has an Iridium spike, period. None of Sarfati's handwaving changes that, even if he tries to falsely make it seem "circular" by admitting that the Iridium spike in the KT boundary supports the "Alvarez theory" (i.e., the meteorite impact), and admitting that the Iridium spike is characteristic of the KT boundary. He's only conceding the evidence.
Conclusion The Bible provides the only coherent framework within which we can properly interpret history, including that of the dinosaurs.
There's nothing "coherent" about a "framework" that flies in the face of all the real-world evidence.
Other theories are doomed to failure, even the glamorous ‘deep impact’ theory, because all circumstantial evidence counts for nothing if it ignores the only eye-witness account we have of Creation and the Flood — the Bible.
Sarfati should have just said this up front and saved himself a lot of trouble. If he wants to believe whatever the Bible seems to say, no matter what the real world actually indicates, then he's welcome to do so. But he shouldn't try to bear false witness about the evidence in the process.
That fails to address the evidence, but if you wish not to see the truth to be found in the world around you, I won't trouble you any further.
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