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Not even close. Fossil dating is based on whether or not certain marker species exist in a particular rock sample. The very same species that gradually evolve

Not even close. Fossil dating is based on whether or not certain marker species exist in a particular rock sample. The very same species that gradually evolve and become extinct on scales of millions of years. The resolution is piss poor, and so unreliable that most wells in petroleum forgo biostratigraphic dating altogether.

pale-hands 8y ago
You seem to be conflating the duration of a geologic event (i.e. rate of change, which is the subject of discussion) with the absolute age.
hwillis 8y ago
You're talking out your ass.[1] > Annually laminated (varved) lake sediments offer considerable potential as high-resolution archives of palaeo-environmental conditions where other high-resolution proxy indicators are not available (e.g., arid terrestrial regions), and latitudes poleward of the treeline (Lamoureux and Bradley, 1996; Wohlfarth et al., 1998; Hughen et al., 2000). When annual deposition of the varves can be independently confirmed (e.g., through radiometric dating), they provide seasonal to interannual resolution over centuries to millennia. Varved sediments can be formed from biological processes or from the deposition of inorganic sediments, both of which are often influenced by climate variations. Three primary climate variables may influence lake varves: (a) summer temperature, serving as an index of the energy available to melt the seasonal snowpack, or snow and ice on glaciers; (b) winter snowfall, which governs the volume of discharge capable of mobilising sediments when melting; and (c) rainfall. Laminated lake sediments dominated by (a) can be used for inferences about past high latitude summer temperature changes (e.g., Overpeck et al., 1997), while sediments dominated by the latter two influences can be used to estimate past drought and precipitation patterns (Section 2.5.2.2). > Ocean sediments may also be useful for high-resolution climate reconstructions. In rare examples, annually laminated sediments can be found (e.g., Hughen et al., 1996; Black et al., 1999) and it is possible to incorporate isotope and other information in climate reconstructions, much as varved lake sediments are used. Otherwise, sedimentation rates may sometimes still be sufficiently high that century-scale variability is resolvable (e.g., the Bermuda rise ocean sediment oxygen isotope record of Keigwin, 1996). Dating in such cases, however, must rely on radiometric methods with relatively poor age control. Biostratigraphic dating isn't how these things are dated. The existence of a species before or after an event isn't how the event is dated. It's not even really that relevant; it relies inherently on species that are not well represented. Instead well represented species, usually ones that didn't die out, are used. Not to mention that biostratigraphic dating is a secondary evidence source... those fossils themselves are dated by far more accurate methods. Near as I can tell, you're basing this opinion off the resolution of radiometric rock dating, which is accurate to about a million years. That has nothing to do with measuring fast changes, which are measured via properties of the rock itself. [1]: https://webcache.googleusercontent.com/search?q=cache:5WiaJ3s-YRoJ:https://www.ipcc.ch/ipccreports/tar/wg1/068.htm+&cd=1&hl=en&ct=clnk&gl=us https://webcache.googleusercontent.com/search?q=cache:5WiaJ3...

pale-hands 8y ago

You seem to be conflating the duration of a geologic event (i.e. rate of change, which is the subject of discussion) with the absolute age.

hwillis 8y ago

You're talking out your ass.[1] > Annually laminated (varved) lake sediments offer considerable potential as high-resolution archives of palaeo-environmental conditions where other high-resolution proxy indicators are not available (e.g., arid terrestrial regions), and latitudes poleward of the treeline (Lamoureux and Bradley, 1996; Wohlfarth et al., 1998; Hughen et al., 2000). When annual deposition of the varves can be independently confirmed (e.g., through radiometric dating), they provide seasonal to interannual resolution over centuries to millennia. Varved sediments can be formed from biological processes or from the deposition of inorganic sediments, both of which are often influenced by climate variations. Three primary climate variables may influence lake varves: (a) summer temperature, serving as an index of the energy available to melt the seasonal snowpack, or snow and ice on glaciers; (b) winter snowfall, which governs the volume of discharge capable of mobilising sediments when melting; and (c) rainfall. Laminated lake sediments dominated by (a) can be used for inferences about past high latitude summer temperature changes (e.g., Overpeck et al., 1997), while sediments dominated by the latter two influences can be used to estimate past drought and precipitation patterns (Section 2.5.2.2). > Ocean sediments may also be useful for high-resolution climate reconstructions. In rare examples, annually laminated sediments can be found (e.g., Hughen et al., 1996; Black et al., 1999) and it is possible to incorporate isotope and other information in climate reconstructions, much as varved lake sediments are used. Otherwise, sedimentation rates may sometimes still be sufficiently high that century-scale variability is resolvable (e.g., the Bermuda rise ocean sediment oxygen isotope record of Keigwin, 1996). Dating in such cases, however, must rely on radiometric methods with relatively poor age control. Biostratigraphic dating isn't how these things are dated. The existence of a species before or after an event isn't how the event is dated. It's not even really that relevant; it relies inherently on species that are not well represented. Instead well represented species, usually ones that didn't die out, are used. Not to mention that biostratigraphic dating is a secondary evidence source... those fossils themselves are dated by far more accurate methods. Near as I can tell, you're basing this opinion off the resolution of radiometric rock dating, which is accurate to about a million years. That has nothing to do with measuring fast changes, which are measured via properties of the rock itself. [1]: https://webcache.googleusercontent.com/search?q=cache:5WiaJ3s-YRoJ:https://www.ipcc.ch/ipccreports/tar/wg1/068.htm+&cd=1&hl=en&ct=clnk&gl=us https://webcache.googleusercontent.com/search?q=cache:5WiaJ3...