Great debate: radiocarbon dating, Mindspawn and Coyote/RAZD

Dust and clay layers between layers that are predominantly diatom shells, layers that took time to accumulate, so there is a distinct identifiable annual pattern. So there is an annual pattern of deposition. First you provide evidence that these purported mechanisms actually work the way you claim and show that salt water did in fact actually enter Lake Suigetsu.Without such evidence this is just fantasy conjecture based on hope.Note three things:(1) salt water is denser than fresh water and so it would be at the bottom of the lake if it entered from the groundwater table -- where it would be under the freshwater lens (which is why islands in the oceans can have fresh water wells). This is basic hydrology, information used by engineers to find fresh water aquifers near oceans.(2) salt water combines with clay to form large fast settling flocs that lock the sodium in the flocks: no sodium has been found in the varves. This is basic soil chemistry.(3) until recent times the level of the ocean was significantly lower:http://www.giss.nasa.gov/research/briefs/gornitz_09/

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Global sea level has fluctuated widely in the recent geologic past. It stood 4-6 meters above the present during the last interglacial period, 125,000 years ago, but was 120 m lower at the peak of the last ice age, around 20,000 years ago. A study of past sea level fluctuations provides a longer-term geologic context, which can help us better anticipate future trends. Figure at right: Generalized curve of sea level rise since the last ice age. Abbreviations: MWP = meltwater pulse. MWP-1A0, c. 19,000 years ago, MWP-1A, 14,600 to 13,500 years ago, MWP-1B, 11,500-11,000 years ago, MWP-1C, ~8,200-7,600 years ago.

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Past, current and future sea level rise | My view on climate change

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Here’s a graph of sea level since the last ice age. As the ice from the last ice age was melting, sea levels rose by some 120 metres over the course of about 8000 years, before it flattened out ~6000 years ago. On the top right, I drew a black line with an approximate slope of 3 mm/year, which is the current rate of sea level rise (over the past 20 years or so). This is much faster than the relatively stable sea level during the ~6000 years before, though not as fast as the sea level rise at the end of the last ice age. Let’s zoom in on the last 9000 years (covering most of the Holocene epoch). The strong sea level rise at the end of the last ice age is still visible on the left hand side, slowing down 7000 years ago and even more so 4000 years ago. Until recently: Current sea level rise represents a clear increase. For the future, most recent estimates of sea level rise fall between 0.5 and 1.5 metres in 2100. It won’t stop thereafter, since there’s a lot of inertia involved in warming up the oceans and in melting (parts of) the large ice sheets (Greenland and Antarctica).

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Clearly at ~8,000 years ago when the Lake Suigetsu varve chronology starts the lake was ~15 meters above sea level and at ~12,000 years ago when the Preboral pine chronology ends it was ~60 meters above sea level and at ~15,000 years and older the lake was at least 100 meters above sea level.These three things combined make it rational to conclude that sea water had absolutely no effect on the diatom/clay cycle no matter how often the moon went around the earth.Enjoy.

Curiously I find this argument to be completely unsupported by facts, and desperately clutching at straws, hardly worth a reply.Uniqueness of location would still have no effect on the data. This is a backwards post hoc ergo propter hoc type fallacy claiming that because they went to that unique location that therefore the data is false?And as I have already demonstrated there could be multiple die-offs of the diatoms and there would be no clay layer between them due to lack of time.Anyone who makes a claim of multiple die-offs causing false layers has the onus of proof to demonstrate that such actually occurs.The reason Lake Suigetsu was chosen was because it had a strong annual deposition. So go do it.My prediction is that you won't be able to discern one year from the next.http://pubs.usgs.gov/circ/circ1171/html/cores.htm

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Cesium-137, a by-product of nuclear testing, was used to date sections of reservoir sediment from the core.

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Age-dating of core sediments was done by analysis of their cesium-137 content. Cesium-137 is a by-product of nuclear weapons testing. It first occurred in the atmosphere in about 1952 and peaked during 1963-64. It adsorbs strongly to fine-grained sediments and therefore can be used to determine the time of deposition of sediments that have been exposed to atmospheric fallout. Cesium-137 first was detected in White Rock Lake core sediments at a depth of 60 to 63 centimeters (1952) and peaked at a depth of 48 to 51 centimeters (1963). The depth of the interface between pre-reservoir and reservoir sediment, 136 centimeters, corresponds to the reservoir construction date (1912), and the top of the core corresponds to the sampling date (July 1994).

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Curiously no annual cores detected even though this is a fairly recent reservoir ... how could they have missed those easy to see layers ...http://polarfield.com/blog/tag/lake-cores/

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Back in the lab, the team is examining cores for organic content (preserved vegetation can be used for radiocarbon dating) and for volcanic ash layers, which can be chemically dated and correlated to other Alaskan lake cores.

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Again they failed to see the annual layers that would have made dating the cores so easy ... how did they miss that common information?Perhaps you should contact these people and volunteer to help them with their dating techniques ... Sure, there is no reason to expect every volcanic eruption to deposit ash in Lake Suigetsu, especially if the prevailing winds were going a different direction.You also need to demonstrate that these eruptions produced ash - not all do - during the periods of the varvesTowada Volcano, Honshu (Japan) - Facts & Information

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The only historic eruption of Towada volcano began on 17 August 915 AD from Ogura-yama lava dome near the Goshikiiwa cone on the NE rim of Nakanoumi caldera wall. The eruptions produced widespread ashfalls and pyroclastic flows.

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So that would not be in the cores (too recent)Aso Volcano, Kyushu (Japan) - Facts & Information | VolcanoDiscovery

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The 24-km-wide Aso caldera was formed during four major explosive eruptions from 300,000 to 90,000 years ago. These produced voluminous pyroclastic flows that covered much of Kyushu. ...

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So that would not be in the cores (too long ago) and not historical documentation ... So that would not be in the cores (too recent).You can't just pick layers and say it must be 'x' volcano -- you need evidence that is consistent with that claim -- each volcano has different elements in it that act like a signature that identifies the volcanoes.Curiously, moving the varves to arbitrarily match one of these volcano eruptions with a tephra deposit (typical creation science approach?) would still not affect the slope of the curve and thus would not have a significant effect on dates ... it does not change the slope of the curve. Ah yes bogus assumed correlations based on an absence of actual objective empirical evidence and a lot of wishful thinking are better than science any day ... Curiously your dates would not mean that "carbon dates after about 1800 bp would have to be recalibrated" because your proposed preposterous assignment of two tephra layers to post AD eruptions would mean 14C would be invalid for those dates ...... we KNOW this is not the case from the other volcano data and the tree rings (you known those rings you could not show any error in their process and AGREED with their historical agreement).So no, this is not any valid criticism, it is just made up fantasy. Through both matching ring widths and 14C variations for the period of the overlap. Note that this is not using 14C ages but the actual levels of 14C in the samples, the levels they have today. Curiously this is objective empirical evidence that has nothing to do with 14C age, it is no different than recording the 14C levels in the atmosphere today.And again you don't understand circular reasoning.For times A to B we have annual rings from the oak chronology, for times B to C we have a period of overlap of oak annual rings and pine annual rings, for times C to D we have annual rings from the pine chronology, so we use the annual rings from A to C from the oak chronologies to match 14C data against and then we have the annual rings from the pine chronology from C to D to match 14C data against ...Where is the circle?And why is there such a good match for the period B to C? if it were just a random match at one end why would the other end match at all? Nope.The fact that you fail to understand what is going on does not make the science invalid, it just demonstrates your ignorance and misunderstanding of fairly simple concepts. Again, you are free to provide evidence of all these other locations. Just making them up is not evidence, you need to document it. Can you give me a link to one -- especially one that does not match the current ones I have extensively documented?If you are going to assert something the onus is on you to provide evidence.Currently I see absolutely no reason to think that there is anything wrong with the annual tree rings and the annual varves discussed to date, as you have failed to present any evidence of error or mistakes. Ah, no. The layers used in Cariaco Basin are alternating layers of foraminifera and sediment ... so once again you provide irrelevant information. No. Really you should read the information provided so you don't make foolish statements. Ignorance is not amusing.An anchored chronology is anchored by a known date, in the case of tree rings they start with the date a core is taken from a living tree. That date is the anchor.When a floating chronology is tethered to an anchored chronology then there is a degree of uncertainty in the match no matter how good it is, because the absolute chronology can be modified by new information (see the change to the German chronology with the beetle infestation) and the floating chronology would move with any corrections to the anchored chronology. It could also be fine tuned by additional information in the floating chronology. This happened with the Preboral pine chronology.Your continued assertions regarding U/Th dating is curious because the margin of error in U/TH is much greater than the margin of error for tree rings and they only serve to show that the tree ring dates are in the right ball park rather than correct the dendrochronology. Again, all you have is innuendo based on a sketchy knowledge of the field, you fail to see that multiple samples are used not just one on one matches and thus your criticism is irrelevant. This is demonstrated by the multiple agreement of dendrochronologies over thousands of years.And which fails to invalidate the consilience between different systems coming to the same results ... again ... If they use different watches should the results vary? Each watch can have different accuracy and precision ... should the results fall within the margins of error or should they vary wildly?Enjoy.

Which curiously shows an annual pattern ... but that is still not the foraminifera layer information ...... I trust you won't argue that these are due to spring tides flooding the basin.The Cariaco basin varves have been used to make a floating marine varve chronology, with diatoms alternating with sediments in an strongly discernable annual deposition pattern. These sediments were used in developing calibration curves for IntCal98 and IntCal04: IntCal04 Terrestrial Radiocarbon Age Calibration, 0-26 CAL KYR BP⁽¹⁾

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This paper focuses on the IntCal04 calibration data set for 14C ages of Northern Hemisphere terrestrial samples. However, because 14C measurements of foraminifera from the Cariaco Basin varved sediments and U-series-dated coral are the basis for the terrestrial calibration data set beyond the beginning of the tree rings at 12.4 kyr, we will discuss marine data in brief. ...

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... The most significant changes (Figure 3c—e) are of course due to the extension of the German dendrochronology from 11.4 to 12.4 cal kyr BP (Friedrich et al., this issue), the new high-resolution Cariaco Basin data set from 10.5 to 14.7 cal kyr BP (Hughen et al., this issue b; Hughen et al. 2000), ...

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Not much about the varves, but we can look at the 2000 paper referenced for more information: (full PDF) or on-line at Synchronous radiocarbon and climate shifts during the last deglaciation⁽²⁾

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... Here we present 14C data from Cariaco Basin core PL07-58PC (hereafter 58PC), providing 10- to 15-year resolution through most of deglaciation. The new calibration data demonstrate conclusively that Δ14C changes were synchronous with climate shifts during the Younger Dryas. Calculated Δ14C is strongly correlated to climate proxy data throughout early deglaciation (r = 0.81). Comparing Δ14C and 10Be records leads us to conclude that ocean circulation changes, not solar variability, must be the primary mechanism for both14C and climate changes during the Younger Dryas.

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Cariaco Basin core 58PC (1040.60′N, 6457.70′W; 820 m depth) has an average sedimentation rate (70 cm/kyr) more than 25% higher than core 56PC (1041.22′N, 6458.07′W; 810 m depth) (13, 14), and shares similar hydrographic conditions. Restricted deep circulation and high surface productivity in the Cariaco Basin off the coast of Venezuela create an anoxic water column below 300 m. The climatic cycle of a dry, windy season with coastal upwelling, followed by a nonwindy, rainy season, results in distinctly laminated sediment couplets of light-colored, organic-rich plankton tests and dark-colored mineral grains from local river runoff (13). It has been demonstrated previously that the laminae couplets are annually deposited varves and that light laminae thickness, sediment reflectance (gray scale), and abundance of the foraminifer Globigerina bulloides are all sensitive proxies for surface productivity, upwelling, and trade wind strength (14, 15). Nearly identical patterns, timing, and duration of abrupt changes in Cariaco Basin upwelling compared with surface temperatures in the high-latitude North Atlantic region at 1- to 10-year resolution during the past 110 years and the last deglaciation (7, 14, 15) provide evidence that rapid climate shifts in the two regions were synchronous. A likely mechanism for this linkage is the response of North Atlantic trade winds to the equator-pole temperature gradient forced by changes in high-latitude North Atlantic temperature (16).

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The hydrography of the Cariaco Basin provides excellent conditions for 14C dating (17). The shallow sills (146 m depth) constrain water entering the basin to the surface layer, well equilibrated with atmospheric CO2. Despite anoxic conditions, the deep waters of the Cariaco Basin have a brief residence time, as little as 100 years (17). Two radiocarbon dates on G. bulloides of known recent calendar age gave the same surface water-atmospheric 14C difference (reservoir age) as the open Atlantic Ocean (7). Good agreement during the early Holocene and Younger Dryas between Cariaco Basin and terrestrial 14C dates, including German pines and plant macrofossils from lake sediments (1, 9, 11, 18) (Fig. 1), suggests that Cariaco Basin reservoir age does not change measurably as a response to increased local upwelling (i.e., during the Younger Dryas) (19). Planktonic foraminiferal abundance permits continuous sampling at 1.5-cm increments, providing 10- to 15-calendar-year resolution throughout most of deglaciation.

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Figure 1: Correlation of variations in 14C compared with calendar age for Cariaco Basin core PL07-58PC and German pines (1). Thick gray line, German pine data set; thin black line and solid circles, Cariaco Basin data. The German pine data set has been revised recently with the addition of 40 years at 11,330 cal yr B.P. (39). The Cariaco and pine 14C data sets were interpolated and resampled at even 5-year increments and were correlated within a moving 1370-year window. The window was shifted in 5-year steps through time lags of +/-300 years. The moving correlation yielded a single point of maximum agreement, r = 0.989 (inset), fixing the beginning of the floating Cariaco Basin varve chronology at 10,490 cal yr B.P. The gray bar shows the timing of the abrupt warming at the transition from Younger Dryas (YD) to Preboreal (PB) conditions in both chronologies. The YD transition was determined by ring widths in the German pines and by gray scale in the Cariaco Basin. 14C uncertainties are shown at 1σ.

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For this work, the varve chronology is largely the same as that used for core 56PC (7). Varves have been re-counted during periods of particular importance, such as the overlap with tree rings and the onset of the Younger Dryas, as well as the deepest, oldest laminations that are less distinct. ...

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The anchored Cariaco Basin varve chronology provides radiocarbon calibration at high resolution from ∼14.8 to 10.5 cal kyr B.P. (Fig. 2) (21). The abrupt beginning and end of the large drop in 14C age during the Younger Dryas onset are shown to be sharp changes in slope rather than gradual transitions. A 14C plateau can be discerned at 11.7 to 11.8 14C kyr B.P., lasting about 250 calendar years. The oldest part of the record is characterized by another plateau at 12.514C kyr B.P., extending beyond (18) the Glacial/Blling boundary where the Cariaco Basin laminations begin. A decrease in 14C age at the Younger Dryas onset of the same amplitude as core 58PC is also seen in coral and Lake Suigetsu data (Fig. 2). ...

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Figure 2 Radiocarbon calibration data set from Cariaco Basin core PL07-58PC compared with those from coral U/Th dates and varved lake sediments. Thin black line and solid circles, Cariaco Basin data; thin gray line, German pine data (1); ... and open circles, varves from Lake Suigetsu, Japan (18). Climatic period abbreviations are as follows: Preboreal, PB; Younger Dryas, YD; Blling/Allerd, B/A; and Glacial, GL. Gray bars indicate timing of the Glacial-Blling transition and the beginning and end of the Younger Dryas based on Cariaco Basin gray scale. 14C and U/Th uncertainties are shown at 1σ.

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Atmospheric 14C concentrations calculated from 58PC calibration data reveal large variations throughout the deglacial period (Fig. 3). The most distinct features are the sharp rise and increased Δ14C during the early Younger Dryas, between 13 and 11.5 cal kyr B.P. Elevated Δ14C during the Younger Dryas has been reported previously (4, 7, 9, 12), but the pattern and timing of change is revealed here in greater detail. In only 200 calendar years, Δ14C rose 70 +/- 10 (22), with abrupt transitions at the beginning and end of the increase. The record also shows century-scale oscillations of 20 to 30 occurring between 15 and 13 cal kyr B.P. A rapid rise in Δ14C (25 in 15 years) occurs at 14.1 cal kyr B.P., followed by a brief period of elevated Δ14C that lasted ∼40 years before declining. More gradual Δ14C increases of ∼30 can be seen at 13.5 and 13.3 cal kyr B.P. (Fig. 3).

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Figure 3: Atmospheric radiocarbon concentration (Δ14C) calculated from Cariaco Basin and tree ring data sets. Solid circles and thin black line, Cariaco Basin core PL07-58PC data; thick gray line, German pine data (1) spliced to the end of the INTCAL98 data set (2). Dashed line is a linear model approximating geomagnetic field intensity used to detrend the raw Cariaco Basin Δ14C data for comparison to other cosmogenic and paleoclimatic data sets. Error bars are 1σ uncertainty calculated by taking into account 14C uncertainties only. The wide gray swath shows total Δ14C uncertainty, including the uncertainty contributed by calendar age error (22).

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To facilitate comparison to other climatic and cosmogenic production records, we subtracted a linear trend from Δ14C (Fig. 3). The trend is intended to represent the decline in atmospheric Δ14C arising from gradually increasing geomagnetic field intensity over the interval of deglaciation (23). ...

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We conclude that the largest of the concurrent changes in climate and atmospheric Δ14C during deglaciation were predominantly of ocean origin, although we cannot eliminate the possibility that some of these events were triggered by the sun. New data here allow for little or no time lag between the initial rise in Δ14C and the associated Younger Dryas climate reversal. ...

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Note that Fig 1 shows how the floating varve chronology was tethered to the German Preboral pine chronology using 14C/12C levels as markers (see Message 112 re tethering with markers), and that the match is very accurate (r=0.989, where r=1 would be an exact match). In note 20 of the paper it talks about the accuracy and precision of this match in greater detail:

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20. The floating German pine chronology was itself anchored to the absolute oak dendrochrology primarily through wiggle-matching 14C variations, but also through matching ring-width patterns. Uncertainty in the absolute pine age is reported conservatively at +/-20 years to account for the relatively short period of overlap (

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The error at the end of the combined European oak chronology is +/-5 years (there is a 10 year difference between the German and Irish chronologies). So the German pine chronology is tethered to the German oak with a maximum error of +/-(5+20) years at ~11,900 calendar years or +/-0.21% error, and the maximum error of the Cariaco Basin chronology is +/-(5+20+10) years, or +/-35 years.Note as well how this information correlates with climate changes, as shown by the tree chronologies before. The reference to magnetic field strength is applicable as this affects the production of 14C, as we shall see later.The chronology was updated in 2004 with improved matches to the dendrochronologies and some revisions to the varve chronology: Cariaco Basin calibration update: revisions to calendar and 14C chronologies for core⁽³⁾

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...Tree-ring chronologies provide high-resolution calibration back to ~12,400 cal BP (Friedrich et al., this issue), but dendrochronologies beyond that age are currently floating and not anchored in absolute age (Kromer et al., this issue). For the previous IntCal98 data set (Stuiver et al. 1998), high-resolution calibration data older than tree rings were provided by Cariaco Basin piston core PL07-PC56 (Hughen et al. 1998). Core 56PC was selected for 14C dating from a suite of 4 adjacent piston cores, mostly due to the quality of its high-resolution grayscale record. The core was sampled every 10 cm, yielding approximately 100- to 200-yr resolution. Cariaco piston core PL07-58PC, on the other hand, has a ~25% higher deposition rate than 56PC (Peterson et al. 1990). Core 58PC was sampled every 1.5 cm, providing 14C calibration at 10—15-yr resolution throughout the period of deglaciation, ~10,500 - 14,700 cal BP (Hughen et al. 2000). ... Here, we present the updated anchoring of the floating Cariaco varve chronology to the revised and extended German pine chronology (Friedrich et al., this issue). In addition, we detail the changes made to the calendar age varve chronology between the publication of the 56PC and 58PC 14C calibrations, ...

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... The original 1998 varve chronology (Hughen et al. 1998) was counted using both thin sections and digital images where the laminations were thick and distinct (Figure 1). However, approximately one-third of the sediment sequence contains darker-colored sediments with thinner, relatively indistinct laminae (Figure 2). ...

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For the high-resolution 14C calibration from Cariaco PL07-58PC (Hughen et al. 2000), the entire sequence of sediment thin sections and digital photomicrographs was re-examined. Image enhancement of the digital images provided increased contrast and magnification to aid identification of laminations wherever they were thinner or less distinct. During reanalysis, many of the indistinct sections originally thought to have been bioturbated were found to have subtle laminations that could be traced across the thin section, more consistent with minimal bioturbation (Figure 2, top). ...

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As a result of this reinterpretation, intervals of the varve chronology containing these faintly laminated sections were expanded as numerous thin varves were counted and added to the chronology. The majority of the chronology was unaffected; however, there were substantial changes in 2 discrete intervals (Figure 3). The earliest Blling -- a period where thick, distinct varves gradually transition from massive, bioturbated sediments of the Last Glacial -- was extended with the result that the Blling period grew by 25%, from 634 to 790 yr. Similarly, during the onset of the Younger Dryas, a large number of additional years lengthened the transition by 33%, from 150 yr to 200 yr. Differences in calendar ages for climate shifts between the 1998 and 2000 varve chronologies resulted from a combination of these discrete additions to the varve chronology as well as the match anchoring Cariaco to tree rings. The 2000 match to tree rings, using much higher resolution Cariaco data than in 1998, resulted in the Cariaco curve shifting to younger ages by ~85 yr. ... There is no evidence to support substantial changes in Cariaco sedimentation during the Younger Dryas, such as deposition of 4 couplets per year rather than two. Therefore, it is unlikely that the length of the Younger Dryas event measured in Cariaco Basin sediments can be much shorter than reported here.

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The new 2004 match to a revised and extended tree-ring chronology (this work -- described below) has shifted the Cariaco chronology back older by 14 yr, but there are no other changes relative to the 2000 varve chronology. The age of the Younger Dryas/Preboreal transition is now placed in the Cariaco chronology at 11,580 cal BP.

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The local Cariaco marine 14C reservoir age was determined by dating 2 samples of pre-bomb forams of known calendar age from box core PL07-BC81 (Hughen et al. 1996). The calendar ages for the samples are 15 and 40 BP, constrained by varve counts, 210Pb ages, and historical dates for 2 large earthquakes in the region that resulted in distinct turbidites in the upper 25 cm (Hughen et al. 1996). The 14C ages measured for the samples are 490 +/- 60 and 460 +/- 50 BP, whereas the marine model from IntCal98 (Stuiver et al. 1998) yields marine ages of 462 and 450 BP, respectively. This results in ∆R values of +28 and +10, for an average of about +20 yr. On this basis, we assigned a Cariaco reservoir age of 420 yr. An alternate reservoir age determination uses the weighted mean difference of Cariaco and tree-ring 14C ages between 10.5 and 12.5 cal kyr BP (Hughen et al., this issue). The mean of the differences, weighted by error, gives the average reservoir age, and the square root of the variance gives the uncertainty. This resulted in a reservoir age of 430 +/- 30 yr, close to the original value as expected, since the Cariaco calendar age was determined by wiggle-matching the reservoir-corrected data to IntCal04 tree rings. However, the reservoir uncertainty of +/-30 yr is robust and is adopted in Table 1. The reservoir age is assumed to have remained constant through the last deglaciation, and has been used to convert Cariaco marine 14C ages to atmospheric values. The best evidence for a constant local Cariaco reservoir age is seen in the close agreement between Cariaco and tree-ring 14C ages across the abrupt Younger Dryas termination (Figure 5). There is no discernible offset between terrestrial and marine 14C despite strongly increased Cariaco upwelling during the Younger Dryas period. This agrees with evidence for a short residence time of carbon in the deep basin, ~100 yr (Holman and Rooth 1990), suggesting that increased upwelling does not result in significantly older water reaching the surface.

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This chronology runs from 10,490 BP to 14,673 BP (last data point in data table 1), and is tethered to the Preboral pine chronology from 10,490 BP to 12,410 BP, or an overlap of 1,920 years with 375 data points listed in table 1.Now it may seem that the consilience between the dendrochronology and the Cariaco Basin varves is forced by intentionally matching one to the other, and this argument would be valid if there were only one or two points used for matching them up ... but there are hundreds of points from the Cariaco Basin varves that match the wiggle patterns of the German pine chronology and the wiggles matched are not linear: there are small wiggles imposed on a larger wiggle pattern. Matching both the large and small scale wiggles with this number of points would be unexpected if they didn't measure the same thing -- actual 14C levels for those ages. This is a longer and better match than the original, where the match had an r value of 0.989. This updated match is shown in Fig 5 above, demonstrating what would be astonishing accuracy if they were totally independent random sequences that just happened to correlate: this consilence is strong validation that these two methods measure the same thing -- annual calendar age. 14C activity and global carbon cycle changes over the past 50,000 years⁽⁴⁾

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... Here, we present a calibration and reconstruction of Δ14C back to 50 cal. ka B.P. on the basis of the correlation of 14C data from Cariaco Basin sediments with the annual-layer time scale of the GISP2 Greenland ice core (12). Similarity between reconstructed Δ14C and variations in 14C production rate estimated from independent paleomagnetic and geochronologic data suggests that the calibration and Δ14C reconstruction are accurate despite the lack of in situ calendric age control. ...

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... Our prior studies of Cariaco Basin sediments made use of annual varve counts to compare timing of abrupt changes in upwelling proxies to calendrically dated instrumental and proxy temperature records in the high-latitude North Atlantic region and indicated that correlative climate changes occurred within 1 year during the past 110 years (15) and within 1 decade during the last deglaciation (13, 16). Laminations are not present continuously, however, across the longer interval of the current study (17). Therefore, calendar age estimates for the new composite 14C record were derived by transferring ages from the GISP2 ice core to Cariaco Basin site 1002 sediments ...

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Precision of the calendar time scale derived in this way has two sources of uncertainty, one pertaining to derivation of the GISP2 time scale itself and another related to correlation between records. Annual layer counts in the GISP2 ice core were used back to about 40 cal. ka B.P. ...

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Accuracy of the GISP2 layer-counting chronology is supported by radiometric dating of correlative records. Calcite δ18O from Hulu Cave in eastern China (20) and δ13C from Villars Cave in southwest France (21) show distinct millennial-scale events during the last glacial period that can be reliably correlated with the GISP2 record. U/Th dates for both caves agree within errors with GISP2 layer counts for the interval from 10 to 40 cal. ka B.P. (20, 21). In addition, records of cosmogenic nuclide flux in GISP2 and Greenland Ice Core Project (GRIP) ice cores show large peaks in 10Be and 36Cl (22) that occurred at ~41 cal. ka B.P. and ~34 cal. ka B.P., according to the GISP2 age model. These have been correlated with marine sedimentary evidence of geomagnetic field intensity minima identified as the Laschamp and Mono Lake excursions, respectively (23). ... recent Ar-Ar dates on Laschamp-correlative tephras yielded ages of 39.4 +/- 0.1 (25) and 41.1 +/- 2.1 cal. ka B.P. (24), in closer agreement with the GISP2 age. ...

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This chronology runs from 10,490 BP to 14,673 BP, and is tethered to the Preboral pine chronology between 10,490 BP and 12,410 BP, or an overlap of 1,920 years with 375 data points, and the overall maximum error from the modern end of the European oak chronology in 2002 to the ancient end of the Cariaco Basin in varve chronology in is +/-35 years in 14,725 years of annual records, an error of +/-0.24%.This extends our knowledge of the age of the earth based on annual counting mechanisms from 12,410 BP (10,460 BCE) to 14,673 BP or 12,723 BCE, another 2,263 years with high accuracy and precision.This also introduces ice cores, and radiometric dating systems, which will be discussed later, and the use of proxies to show climate and magnetic field fluctuation effects. The earth is at least 14,736 years old (2013)The minimum age for the earth is now at least 14,736 years old (2013), based on the highly accurate and precise varve counting system, strong correlation r-factor and with an error of 0.24%.This also means that there was no major catastrophic event that would have disturbed or buried the varves or their process of deposition.This is significantly older than many YEC models (6,000 years for those using Archbishop Usher's assumption filled calculations of a starting date of 4004 BCE).And this is still only the start of annual counting methods.Enjoy.

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References

1. Reimer, P. J., Baillie, M.G.L., Bard, E., Bayliss, A., Beck, J. W., Bertrand, C. J. H., Blackwell, P. G., Buck, C. E., Burr, G. S., Cutler, K. B., Damon, P. E., Edwards, R. L., Fairbanks, R. G., Friedrich, M., Guilderson, T. P., Hogg, A. G., Hughen, K. A., Kromer, B., McCormac, G., Manning, S., Ramsey, C. B., Reimer, R. W., Remmele, S., Southon, J. R., Stuiver, M., IntCal04 Terrestrial Radiocarbon Age Calibration, 0-26 CAL KYR BP, Radiocarbon, Vol 46, Nr 3, 2004, p 1029—1058 https://journals.uair.arizona.edu/...icle/download/4167/3592
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3. Hughen, K.A., Southon, J.R., Bertrand, C.J.H., Frantz, B., Zermeo, P., Cariaco Basin calibration update: revisions to calendar and 14C chronologies for core PL07-58PC. Radiocarbon, Vol 46, Nr 3, 2004, p 1161-1187 https://journals.uair.arizona.edu/...icle/download/4175/3600
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