Presentation on theme: "Dendrochronology Sean D. Pitman, M.D. March 2006 www.DetectingDesign.com Methuselah Tree Dated at 4,767 years old The Oldest Living Thing."— Presentation transcript:
Dendrochronology Sean D. Pitman, M.D. March Methuselah Tree Dated at 4,767 years old The Oldest Living Thing
History of Dendrochronology Andrew Ellicott Douglass ( ) –American Astronomer and Father of Dendrochronology –Discovered a correlation between tree ring patterns and sun spot cycles (beginning in 1884) –Initially doubted by most scientists Edmund Schulman ( ) –From the University of Arizona –Made Bristlecone pines famous; studied them for over 30 years (primarily in the White Mountains at between 9,500 to 11,500 ft)
Charles W. Ferguson –With H.C. Fritts, carried on work with Bristlecone pines started by Schulman (starting about 1967) –Noticed that dead wood scattered on the surrounding slopes did not match existing ring patterns, creating a gap in time between the living and the dead wood –The gap was first breached by A.E. Douglas while testing prehistoric beams in ruins near Show Low, Arizona –Ferguson eventually able to construct a continuous tree-ring record reaching as far back a 8,680 years before present –During the 1980s the sequence was extended back to about 11,300 years B.P. –Used radiocarbon dating to help validate tree ring chronologies –Never released data for independent validation
Similar tree-ring chronologies and dates have been obtained for European oak and pine tree sequences Tree-rings have since been used to correct or calibrate radiocarbon dates Radiocarbon dates have also been used to calibrate tree ring dates
Potential Problems? Minor potential problems? –Certain studies have shown that occasionally Bristlecone pines do not produce a ring for a given year and, more commonly, produce an extra ring during some years –Lammerts (1983) found extra rings after studying the development of Bristlecone saplings. He suggested that the existing chronology should be compressed by up to 20% because of this problem alone. Lammerts, Walter E. (1983), Are the Bristlecone Pine Trees Really So Old?, Creation Research Society Quarterly, 20: , September.
False Band True Band University of Arizona Dept. of Dendrochronology
More Difficult Problems? D.K. Yamaguchis (1986) auto correlation problem: –Noticed that tree ring sequences tend to cross-match or auto correlate in several different places within a master tree ring chronology –Proved this by matching a 290-ring Douglas-fir log (known, by historical methods, to date between 1482 and 1688) to multiple non-overlapping places (6) within the Pacific Northwest Douglas Fir Master Growth-ring Sequence –Demonstrated that his log could cross-match with other tree-ring sequences to give t-values of around 5 at AD 1504, 7 at AD 1647 and 4.5 at AD 1763 (t-values of >3 equal a match greater than 99.9%) Yamaguchi DK Interpretation of cross correlation between tree-ring series. Tree-Ring Bulletin 46:47-54.
Garry Bog2 (GB2) and Southwark sequences (England) –Used to connect the Northern Ireland Belfast absolute chronology (i.e., the AD sequence) to the 'floating' Belfast long chronology (i.e., the BC sequence), and ultimately used to re-date the South German chronology –Have t-values that are considerably lower than those obtained for some of the historically incorrect dates produced by Yamaguchi's experiment ( i.e. ~ 3 ) Rohl, David, A Test of Time, Arrow Books, London, Appendix C, 1996.
Anatolia There is currently only one (substantial) master dendrochronology from anywhere in the Ancient Near East. Hence this master dendrochronology has great importance. This master is from Anatolia. Anatolia is a geographical term, roughly designating modern Turkey. A master dendrochronology for Gordion (39.7 °N, 32.0 °E), in central Anatolia, was first developed in the 1970s. This master dendrochronology, however, does not extend continuously from the present to the past. The master has been anchored in timei.e. datedlargely via radiocarbon (originally, the master was dated via archaeo-history). In what follows, much of the work that has been done in Anatolian tree-ring matching is reviewed. The conclusions are disturbing, and have implications for tree ring studies generally. Douglas J. Keenan, Anatolian tree-ring studies are untrustworthy, The Limehouse Cut, London E14 6N, United Kingdom; 16 March 2004
P. Kuniholms Turkish Tree-Ring Chronology –Tille Hoyuk (ancient city) gateway wood showed t- value wiggle-matches for 1258, 1140, and 981 B.C. - each with a greater than 99.9% certainty –This Chronology was constructed with the use of many trees (26) with few rings –6 specimens had fewer than 40 rings and 21 specimens had fewer than 60 rings, only 2 had more than 100 rings and their overlap comprised only 33 rings –Despite this master sequence being much acclaimed, its reliability is significantly flawed - so much so that it is statistically worthless as a master sequence Kuniholm, P : Appendix in G. Summers: Tille Huyuk 4, pp Douglas J. Keenan, Anatolian tree-ring studies are untrustworthy, The Limehouse Cut, London E14 6N, United Kingdom; 16 March 2004
Examples of Two Matches Known to be False - From Tılle Höyük Douglas J. Keenan, Anatolian tree-ring studies are untrustworthy, The Limehouse Cut, London E14 6N, United Kingdom; 16 March 2004
Douglas J. Keenan, Anatolian tree-ring studies are untrustworthy, The Limehouse Cut, London E14 6N, United Kingdom; 16 March 2004 Gateway master Gordion Master Random
Visual Matching Visual Match of a shipwreck published in 1998 (Wiener, 1998; p. 314) –Wood dated against the Gordion Master via visual matching –The match was published by both Kuniholm and Manning (see following figure)
In 1999, a letter was sent to various lists, and also to the principal investigator in Anatolian tree-ring studies, pointing out some of the above (especially the statistical aspects) and concluding that there was no tree-ring match for the shipwreck wood [James, 1999]. Two years later, in the next major paper in Anatolian tree-ring studies, the tree-ring date for the shipwreck was acknowledged to be not especially strong [Manning et al., 2001: n.38]. Douglas J. Keenan, Anatolian tree-ring studies are untrustworthy, The Limehouse Cut, London E14 6N, United Kingdom; 16 March 2004
The central conclusion is clear: Anatolian tree-ring studies are very untrustworthy and the problems with the work should be plain to anyone who has familiarity with the field. This is a serious matter. Consider that the work has been published in respected research journals and been ongoing for many years. How could this have happened? Douglas J. Keenan, Anatolian tree-ring studies are untrustworthy, The Limehouse Cut, London E14 6N, United Kingdom; 16 March 2004 Douglas Keenan, Why Radiocarbon Dates Downwind from the Mediterranean are too Early, Radiocarbon, Vol 44, Nr 1, 2002, p 225–237
Dendrochronologists working in Hohenheim, Germany, were proven wrong three times in the mid 1990s in the development of their master sequence, each time after very strong assertions of reliability. Douglas J. Keenan, Anatolian tree-ring studies are untrustworthy, The Limehouse Cut, London E14 6N, United Kingdom; 16 March 2004 Douglas Keenan, Why Radiocarbon Dates Downwind from the Mediterranean are too Early, Radiocarbon, Vol 44, Nr 1, 2002, p 225–237
Climatic Conditions The master dendrochronologies for Scotland and Northern Ireland match extremely well during 1800–1899 (t-scores indicate % confidence), but much less well during 1700–1799 (t-scores indicate % confidence) [Baillie, 1982: p.109]. Similarly, master dendrochronologies for Exeter and Nantwich (both in England, about 275 km apart) match acceptably during AD 1061–1216 (t-scores indicate % confidence), but hardly at all during AD 930–1060 (t- scores indicate 60% confidencei.e. roughly the same as flipping a coin) [Hillam,1980] –This second example, in particular, illustrates the danger that a changing climate can pose for tree-ring matching. Douglas J. Keenan, Anatolian tree-ring studies are untrustworthy, The Limehouse Cut, London E14 6N, United Kingdom; 16 March 2004
LaMarche  measured living trees at two sites in Nevada that were on the same side of a mountain –One site is just 130 m higher than the other, near the tree line –The ring widths of trees from the two sites showed no general correlation Hillam  compared master dendrochronologies from two sites at York, England, with a master dendrochronology from Exeter, also in England –York site compared with Exeter gave a t-score of only 0.5, and yet the second York site compared with Exeter gave a t-score of 3.5. –These English master dendrochronologies also include few trees, which weakens matching Douglas J. Keenan, Anatolian tree-ring studies are untrustworthy, The Limehouse Cut, London E14 6N, United Kingdom; 16 March 2004
The timber circle at Holme-next-the-Sea in Norfolk, England
Timber Circle at Holme, England Discovered in 1998 Circle of 55 inverted Oak Trees A 168-year ring chronology created Site chronology compared with several reference tree ring chronologies
This tree-ring sequence was compared with a series of reference chronologies. The highest... correlation was against the East Anglia chronology (t-3.98; higher t-values are more significant), giving an end date for the site chronology of 2050 BC. It also produced lower correlations against East Anglia ending at 2454 BC (t-3.17) and 2019 BC (t-3.14). Running the ring pattern against the Irish master gave correlations of t-3.39 at 2050 BC, but only t-0.96 at 2454 BC and t-1.7 at 2019 BC. NATURE | VOL 402 | 2 DECEMBER 1999 |
Probability distributions of dates from the central tree bole at Holme-next-the-Sea. Each distribution represents the relative probability that an event occurs at a particular time. For each radiocarbon date, two distributions have been plotted: one in outline (the result of simple radiocarbon calibration), and a solid one (based on the chronological model used). The agreement indices provide a measure of how well the radiocarbon measurements agree with the absolute date suggested by dendrochronology [i.e. 26.7% ]
Interlaboratory offsets, errors and regional variation in the radiocarbon content of the atmosphere may be significant when producing precise archaeological chronologies. NATURE | VOL 402 | 2 DECEMBER 1999 | How significant can these errors be? How precise can one be given such errors? What is the predictive value of this science?
Dendrochronology a Science? In almost all branches of science, other than tree-ring studies, there is a check on the validity of published research: other researchers can, and often will, independently seek to replicate the research. For example, if a scientist does an experiment in a laboratory, comes to some interesting conclusion, and publishes this, then another scientist will replicate the experiment, in another laboratory, and if the conclusion is not the same, there will be some investigation. The result is (i) a scientist who publishes bogus research will be caught (at least if the research has importance and is not extremely expensive to replicate) and (ii) because all scientists know this, bogus science is rare. Tree- ring studies do not have this check, because the wood that forms the basis of a tree-ring study is irreplaceable: no other researchers can gather that wood. Additionally, tree-ring investigators typically publish little more than conclusions. This is true everywhere, not just for Anatolia. Moreover, there is little competition among tree-ring investigators, in partand this is crucial because investigators in one region typically do not have access to data from other regions. The result is a system in which investigators can claim any plausible results and yet are accountable to no one. - Keenan Douglas J. Keenan, Anatolian tree-ring studies are untrustworthy, The Limehouse Cut, London E14 6N, United Kingdom; 16 March 2004
Kuniholm himself made the following observations about the state of the "science" of dendrochronology at the present time: "I, for one, was quite surprised to learn that dendrochronological data … is considered highly proprietary. … The value … of the … dendrochronological database is vitiated if there are no data attached and therefore available for use by others…. We must keep in mind that unpublished information is next to worthless." Kuniholm P.I. (2002), "Archaeological dendrochronology", Dendrochronologia 20: 63–68
As a tree physiologist who has devoted his career to understanding how trees make wood, I have made sufficient observations on tree rings and cambial growth to know that dendrochronology is not at all an exact science. Indeed, its activities include subjective interpretations of what does and what does not constitute an annual ring, statistical manipulation of data to fulfill subjective expectations, and discarding of perfectly good data sets when they contradict other data sets that have already been accepted. Such massaging of data cannot by any stretch of the imagination be considered science; it merely demonstrates a total lack of rigor attending so-called dendrochronology research". Rod A. Savidge, PhD Professor, Tree Physiology/Biochemistry Forestry & Environmental Management University of New Brunswick Fredericton, NB E3B 6C2 NYTimes.com 11/12/02
What About Radiocarbon Calibration?
Neutron captured and proton released by Nitrogen 14 A proton is effective converted into a neutron Stable carbon has 6 protons and 6 (or 7) neutrons – Carbon 12 (~99%) or Carbon 13 (~1%) Carbon 14 (~0.6%), with 8 neutrons and only 6 protons, is therefore unstable and turns back into Nitrogen 14 with the emission of a negatively charged beta particle – turning a neutron back into the desired proton Half life ~ 5730 years
Willard F. Libby (Father of Radiocarbon dating) wrote: "If the cosmic radiation has remained at its present intensity for 20,000 or 30,000 years, and if the carbon reservoir has not changed appreciably in this time, then there exists at the present time a complete balance between the rate of disintegration of radiocarbon atoms and the rate of assimilation of new radiocarbon atoms for all material in the life-cycle." Libby, in his Radiocarbon Dating, stressed that the method is good only on the condition that the influx of cosmic rays has not changed during the last 20 or 30 thousand years, and also that the quantity of water in the oceans has not changed in the same period of time. W.F.Libby, `Radiocarbon Dating', Chicago, 1952, pp. 4-9
Problem? C14 formation and decay is not in equilibrium Radiocarbon forming 28% - 37% faster than it is decaying Melvin A. Cook, `Nonequilibrium Radiocarbon Dating Substantiated', Vol. 2, Pittsburgh, 1986, pp
From the Symposium Organized By International Atomic Energy Authority, H. E. Suess, UCLA:...presented the latest determinations... as adduced from the current activity of dendrochronologically dated growth rings of the Californian bristle cone pine....The carbon14 concentration increases rather steadily during this time… These results confirm the change in carbon14 concentration.... and indicate that the concentration increases... (Science, Vol.157, p.726) Note: Increasing modern C14 would make older things look even older.
What About Old Things Looking Too Young? Major trend in the plot of dendrochronology vs. radiocarbon dates. Dates above dashed zero line overestimate tree-ring ages; dates below underestimate tree-ring ages (Taylor, 1987, Figure 2.8).
Local Effects and Specimen Variability? Things often look too old or too young in Radiocarbon age depending on environmental conditions or the type of specimen being dated - and have nothing at all to do with actual age
Archaeologists studying the Ancient Near East have claimed that radiocarbon dates are older than archaeo-historical dates (Earlier testing, before calibration, showed C14 dates of ancient Egyptian artifacts as being too young) In a 2001 issue of Radiocarbon that was devoted to Ancient Near Eastern chronology, the introductory survey paper concluded that the Collective evidence … clearly indicates … major chronological disparities between 14C and archaeo-history for the early historical period (Bruins 2001) A 1989 summary review in Radiocarbon noted that the "incompatibility between … radiocarbon dates and the archaeologic/historic dates of Mesopotamia and Egypt" was a major problem (Weinstein 1989) Douglas Keenan, Why Radiocarbon Dates Downwind from the Mediterranean are too Early, Radiocarbon, Vol 44, Nr 1, 2002, p 225–237
Consequently, some Ancient Near Eastern archaeologists have gone on record stating that they do not accept dates based on 14C. For example, a reviewer of 14C dates from Sardinia concluded: I will only accept … dates provided by [14C] as indicative when they do not blatantly contradict information already obtained by using [archaeological] methods (Tinè 1998). And a respected Egyptologist says similarly: I am mistrustful. … [14C dating] does not often match with historical dating (Wiener et al. 1995). Some archaeologists have said that if they attempt to publish 14C dates contradicting archaeo-historical chronologies, their papers are rejected (Nelson et al. 1990). One archaeologist, reviewing the situation for the eastern Mediterranean, concluded blandly: … radiocarbon dates are invoked if they support a particular hypothesis … and dismissed if they do not" (Merrillees 1992). Douglas Keenan, Why Radiocarbon Dates Downwind from the Mediterranean are too Early, Radiocarbon, Vol 44, Nr 1, 2002, p 225–237
What if? What if the Earths magnetic field was a lot stronger in the past? –Less C14 production = Older apparent age What if a very large catastrophe came along that buried a whole lot of Carbon 12? What would that do to the C14/C12 ratio? Less C12 = reduced apparent age More C12 = Increased apparent age
Lots and Lots of C12 The Biosphere currently contains ~39 trillion metric tones of carbon 12 6,820 trillion metric tons of carbon currently buried in the form of coal, oil, and other fossils – about 175 times the amount of organic matter living today If one adds a portion of sedimentary carbonates to this figure (a fraction of the 20,000 trillion tons that are buried), the number could jump significantly higher
Without even considering the vast quantities of calcium carbonate, there is enough carbon 12 buried in the fossil coal, oil, and other fossils to reduce the apparent ratio of 14 C to 12 C by about 7 half-lives Would result in a dramatic increase in apparent age if most of the fossil 12 C were once available at about the same time If buried suddenly by catastrophe, subsequent 14 C to 12 C ratios would be affected; would no longer be in equilibrium and would change over time A dramatic increase in the ocean size (carbon sink) might also play a significant role
Ancient peat: –marked decrease in carbon 14 ratios at lower and lower levels (i.e., decreased carbon 14 with older age well beyond what would be expected with radioactive decay) Robert H. Brown, The Implications of C14 Age vs. Depth Profile Characteristics, Origins 15(1):19-29 (1988) (http://www.grisda.org/origins/15019.htm)
Peat profile from Beauchêne Island, Falkland Islands (data from Smith and Prince 1985). Dashed adjustment to regression line provides most reasonable estimate of slope and curvature at C yr (see also Smith and Clymo 1985) R.H. Brown, The Implications of C14 Age vs. Depth Profile Characteristics, Origins 15(1):19-29 (1988)
Rampart Cave in the grand wash cliffs of the lower end of the Grand Canyon has ~ 127cm of animal dung, mainly produced by the American three-toed sloth. Notice how the C14 curve suddenly drops off in a non- linear fashion with infinite ages (i.e. no C14) produced beyond 100cm of depth R.H. Brown, The Implications of C14 Age vs. Depth Profile Characteristics, Origins 15(1):19-29 (1988)
Comparisons between Northern Ireland oak and New Zealand cedar chronologies Same interval from A.D. –About 160 years Carbon 14 was different by 3.4% ± 0.6% Translates to about 27.2 ± 4.7 years This is about a 17% difference between the C14 age at one verses the other site F. G. McCormac, A. G. Hogg, T. F. G. Higham, M. G. L. Baillie, J. G. Palmer, Limin Xiong, J. R. Pilcher, David Brown and S. T. Hoper, Variations of Radiocarbon in Tree Rings: Southern Hemisphere Offset Preliminary Results, Radiocarbon Volume 40(1998), Number 3, page 1153 ff. ( )http://www.radiocarbon.org/PDF/v40n3/mccormac.pdf
Recently, Damon, Cheng and Linick (1989), Damon et al. (1992) and Damon (1995a,b) have identified significant differences (ca. 4-7%) between contemporaneous tree rings in the same hemisphere from Tucson, the Olympic Peninsula of Washington State and the Mackenzie Valley in the Arctic Circle. - Compare to the 3.4% difference noted previously F. G. McCormac, A. G. Hogg, T. F. G. Higham, M. G. L. Baillie, J. G. Palmer, Limin Xiong, J. R. Pilcher, David Brown and S. T. Hoper, Variations of Radiocarbon in Tree Rings: Southern Hemisphere Offset Preliminary Results, Radiocarbon Volume 40(1998), Number 3, page 1153 ff. ( )http://www.radiocarbon.org/PDF/v40n3/mccormac.pdf
McCormac et al. (1995) have suggested location-dependent differences in 14C from contemporaneous trees in Ireland and the United States; Stuiver and Braziunas (1998) and McCormac et al. (1998) have shown variations in the value of the interhemispheric 14C offset. These authors have suggested that regional effects may not be temporally constant. F. G. McCormac, A. G. Hogg, T. F. G. Higham, M. G. L. Baillie, J. G. Palmer, Limin Xiong, J. R. Pilcher, David Brown and S. T. Hoper, Variations of Radiocarbon in Tree Rings: Southern Hemisphere Offset Preliminary Results, Radiocarbon Volume 40(1998), Number 3, page 1153 ff. ( )http://www.radiocarbon.org/PDF/v40n3/mccormac.pdf
Sample Equivalent C- 14 Age C-14/C-12 Ratio re 1950 A.D. Standard Excess Over Machine Background Machine Background without a sample 60, , Unprocessed Finland Bedrock 63,500 ±2, ± Unprocessed Meteorite56,500 ±1, ±.00020ca Unprocessed Natural Graphite 54, , "Infinite" Age Samples: anthracite, bone, calcite, graphite, limestone, shell, wood 40, , AMS Data for "Infinite" C-14 Age Samples. Data from seven laboratories reporting in Radiocarbon 28(2A):
The Weight of Evidence Are tree ring and radiocarbon dating techniques actually good enough to convincingly overturn the Genesis account of a recent worldwide flood? – A massive catastrophe which wiped out much life and buried trillions of metric tons of carbon suddenly some 4 or 5 thousand years ago?