You are being given very good information by rox and edge, and I do not understand why you keep repeating your original position in the face of what they are saying. Particularly claims that ancient dates were believed and so imposed on geologic theory, and things like...
To account for the sharp demarcations between the different sediments (evident all over the southwest and in any photo of the layers anywhere) I have to imagine an ABRUPT climate change rather than a gradual one
... which suggests you do not understand the history or explanations of geology. Not to mention statements like...
The presentation of the strata is of neat straight layers -- yes not PERFECTLY neat and straight for the obsessionals out there who want to derail the point by mentioning the differences in thickness and the irregularities between the layers that are only visible very close up.
... which suggests you have not studied actual maps of strata, beyond perhaps those dealing with surficial (exposed) cross cuts of the grand canyon.
I will try to run through this quickly, again, with links for further information. As has been noted, the conception of ancient dates was NOT an intrinsic part of geology. The identification of layers of sediment does not require knowledge of dates or even concepts of them. I assume you would at least agree with that proposition, that we can identify different strata based on differing compositional material.
It was out of identifying strata that
stratigraphy emerged. Read the link for a more in depth discussion, but important to note...
Stratigraphy, a branch of geology, is basically the study of rock layers and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. The subject was essentially invented and first rigorously applied by William Smith in England in the 1790s and early 1800s.
This was without a concept of absolute dates, or dating methods. Where and how did "deep time" emerge?...
Biostratigraphy or paleontologic stratigraphy is based on fossil evidence in the rock layers. Strata from widespread locations containing the same fossil fauna and flora are correlatable in time. Biologic stratigraphy was based on William Smith's principle of faunal succession, which predated, and was one of the first and most powerful lines of evidence for, biological evolution. It provides strong evidence for formation (speciation) of and the extinction of species. The geologic time scale was developed during the 1800s based on the evidence of biologic stratigraphy and faunal succession.
This clearly states that deep time was emerging as a concept BEFORE evolution, and it was from looking at composition of strata and how those strata interact with each other. One of the most common relative dating methods was the principle of original horizontality and the
Law of Superposition. Again, read the link to get a more detailed explanation. But from this there are some important notes...
In its plainest form...: layers of rock are arranged in a time sequence, with the oldest on the bottom and the youngest on the top, unless later processes disturb this arrangement. The law was first proposed in the 17th century by the Danish scientist Nicolas Steno.
...Steno realized that other geological processes could create apparent exceptions to his laws of superposition and horizontality . He reasoned that the formation of caves might remove part of a lower layer, and that the collapse of a cave might transport large pieces of an upper layer downwards. He recognized that rocks might be uplifted by subterranean forces. Geologists now recognize that tilting, folding, and faulting may also complicate the analysis of a stratigraphic sequence. Molten rock may force its way through surrounding rocks and may sometimes squeeze between older rock layers, also forming an exception to Steno's law. However, such anomalies leave physical evidence in the disturbed rocks; for example, faulted rock layers may be cracked, broken, or metamorphosed along the fault lines.
Steno's law is a statement of relative time, not absolute time: two rock layers, in principle, could form millions of years apart, or days apart.
Steno predates and could be called the prefounding father of geology, most certainly stratigraphy. His work began the journey and what happened to him is of note and bears on this discussion...
Steno himself saw no difficulty in attributing the formation of most rocks to the flood mentioned in the Bible. However, he noticed that, of the two major rock types in the Apennine Mountains near Florence, Italy, the lower layers had no fossils, while the upper ones were rich in fossils. He suggested that the upper layers had formed in the flood, after the creation of life, while the lower ones had formed before life had existed. This was the first use of geology to try to distinguish different time periods in the Earth's history - an approach that would develop spectacularly in the work of later scientists...
The Law of Superposition is widely used in creation science to refute geological scientific arguments on the age of the Earth... Such arguments are naturally fallacious, because Steno did not recognise fining up sequences, and the Law of Superposition has, (as all scientific laws have), been modified to take into account modern conceptions and increased knowledge of the natural world.
After enough investigation into geology Steno began to see problems for his faith and renounced geology to re-embrace theology. Note above that Steno (and this is before deep time was proposed) realized that the Flood was inconsistent with the entire geologic column (as you have suggested here). Thus you cannot assert deep time, or renunciation of scripture, was itself a prereq for dating or finding inconsistencies between Flood mythology and what is in the rock, particularly when looking at the entire geologic record. Steno was dealing with an incomplete record and had already found problems, despite his piety.
Indeed if one looks at the actual strata one finds that demarcations must be made to try and save Flood theory, which actually hurts YE theory... and with later discoveries only further hurts Flood theory. Furthermore, this is without addressing issues of dating based on the obvious FACT that in clastic rock the original rock fragments had to have formed and then eroded (adding to deep time) in order to become part of another rock.
Now lets look at your claim regarding rock being layered smooth and straight. As mentioned above, faults and folds have been found in rock.
Here is a link to a description of Appalachian strata structure. Scroll down to the middle of the page where it starts in on ramps and thrusts to find a cross cut map which is anything but horizontal and straight.
Or look here.
Or here.
My apologies for not being savvy enough to insert the pictures into my posts, but they are there and you need to address their existence. It does not look like Grand Canyon, which is what you seem to want to hold onto as your only example of strata. It is mixed up and not in ways that could have occured if it was all loose sediment swirling around. Vast layers had to have settled and solidifed, and then broken and shifted.
This is part of the geologic record, please explain.
I will leave it here for now, but as a forewarning I have not begun to discuss igneous rock intrusions into sed strata. These formations... dikes, sills, plutons... also force greater relative dates as strata it pushes through or borders with must have been laid down earlier and fully hardened, before the igneous structures which then had to cool (which means time), before sed layers were deposited on top of them.
There is more in the maps of earth than were imagined in your philosophy Faith. Perhaps you will have to reach the conclusion of Steno (abandon all discussion of geology to preserve faith), but you cannot pretend that the geologic record is as you suggest, or that your conclusions are reasonably attained from that record. Even Steno could not wave his hand that hard.
This message has been edited by holmes, 03-12-2006 01:07 PM
holmes
"What you need is sustained outrage...there's far too much unthinking respect given to authority." (M.Ivins)
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