Replies

Here's the after and before of Sturt Manning's view, the first one being (literally) in the fine print (bold and italics in the original, retyped by yours truly) of the PDF file linked here:

The Thera (Santorini) Volcanic Eruption
and the Absolute Chronology
of the Aegean Bronze Age
by Sturt W. Manning
website
Work in the later 1980s through earlier 2003 appeared to offer grounds for perhaps linking the great Thera eruption with likely climate anomalies recorded in tree-ring archives and/or with evidence for a large volcanic eruption recorded in Greenland ice-cores. Where these dates were consistent within the date range indicated by the radiocarbon evidence, it seemed that these dates might indeed indicate a precise date for the Thera eruption. The most likely date adopted in Test of Time, c. 1628BC, came from the tree-ring evidence, and, at that time, this seemed potentially capable of association with indications of major eruptions in ice core records. But since the end of the 1990s this nexus of evidence has broken down. First, it became clear that the date of the best ice-core (Dye 3) was NOT compatible with the tree-ring growth anomaly in 1628BC — it instead dated c. 1644BC give or take only about 4 years by publications of AD2000. This removed most of the argument that the two evidence sources were compatible, and thus the case that both reflected the same major volcanic eruption. Later a date of c. 1645BC for Thera was suggested from ice-core evidence (Hammer et al. 2003). HOWEVER, it is important to note that critical analysis of the provenance data available from the GRIP ice-core indicates that the volcanic glass found there is in fact NOT from Thera — contrary to earlier suggestions and indications. Thus there is at present no evidence linking the Thera eruption with the volcanic acid signal c.1645BC. See the papers by Pearce et al. (2004) and Keenan (2003) for full details. This analysis means that suggestions of a Thera-Greenland ice-core date link mentioned on the basis of pers. comms from the ice-core team in a Test of time are now irrelevant. The tree-ring evidence was never claimed to be directly linked to Thera (or any volcano) — the argument advanced was of a plausible association with the tree-rings offering therefor a proxy record... there is at present no direct of causal linkage... This means that, as of late AD2003, we have only two data sources to resolve the date of the Thera eruption: (i) conventional archaeohistoric methods, and (ii) radiocarbon.

Manning's clinging to radiocarbon dates which due to the enriched "dead" carbon of the soil of Santorini are dubious, while hoping that someone eventually finds a link in ice-core data, since all the previous claims have blown away in the wind. Here's S.M.'s view from a few years ago, from his The Test of Time period, which isn't too different from his current view:

The Thera (Santorini) Volcanic Eruption and
the Absolute Chronology of the Aegean Bronze Age
by Sturt W. Manning
...It is argued that the key Late Minoan IA period, the high point of the Minoan civilisation, was not, as conventionally held, contemporary (even in part) with the New Kingdom (18th Dynasty) of Egypt, nor the Late Bronze 1 phase of the Levant. Instead, the Late Minoan IA period in the Aegean is linked with the late Middle Bronze Age of Syria-Palestine, the Second Intermediate (Hyksos) Period of Egypt, and the Late Cypriot IA period of Cyprus. This is an important realignment of cultural synchronisations. The high point of Crete should be considered in terms of the dominant Canaanite trading system of the late Middle Bronze Age, and not New Kingdom Egypt...

Appendix 2: Why the standard chronologies are approximately correct, and why radical re-datings are therefore incorrect.

Interestingly enough, Manning cites Lesson 17 which, while it toes the line regarding the current dating fictions, also notes that:

"More recently, the vulcanologists have claimed that the Santorini caldera formed quite gradually and that a tidal wave, if indeed there was one at all, would not have been on anything like the scale envisaged by Marinatos and other proponents of the link between the Theran volcano and the sudden decline of Neopalatial Crete."

More from the same page:

Akrotiri on Thera, the Santorini Volcano
and the Middle and Late Cycladic Periods
in the Central Aegean Islands
Bronze Age Aegean chap 17
Trustees of Dartmouth College
Revised: Friday, March 18, 2000
[T]he simple facts are that the great earthquake which badly damaged Akrotiri is to be dated quite early in LM IA (either ca. 1650 or ca. 1560 B.C.?), that the entire town was buried in meters of volcanic ash still within the LM IA period (ca. 1625 or ca. 1550/1540 B.C.?), and that the wave of destructions (most of them including fires) which defines the end of the Neopalatial period on Crete and to which the palaces at Mallia, Phaistos, and Zakro all fell victim cannot be dated earlier than LM IB (ca. 1480/1470 B.C.?). Hood [TAW I (1978) 681-690] claims that clear evidence of the earthquake which so severely damaged Akrotiri before the town was buried is to be found at several sites on Crete where it is clearly dated to LM IA. More importantly, tephra from the later eruption of the Theran volcano has been found within the past decade in LM IA contexts on Rhodes (at Trianda) and Melos (at Phylakopi) as well as on Crete itself, ample confirmation that the eruption preceded the LM IB destruction horizon on Crete by a significant amount of time. Thus no direct correlation can be established between the Santorini volcano and the collapse of Neopalatial Minoan civilization.

IOW, the eruption which covered Akrotiri was long before the Neopalatial period on Crete ended.

Debate erupts anew:
Did Thera's explosion
doom Minoan Crete?
William J. Broad NYT
Thursday, October 23, 2003
In 1939, Spyridon Marinatos, a Greek archaeologist, proposed that the eruption wrecked Minoan culture on Thera and Crete. He envisioned the damage as done by associated earthquakes and tsunamis. While geologists found tsunamis credible, they doubted the destructive power of Thera's earthquakes, saying volcanic ones tend to be relatively mild... Despite the power of Thera, the Danish scientists' evidence raised doubts about its links to the Minoan decline. Their date for Thera's explosion, 1645 B.C., based on frozen ash in Greenland, is some 150 years earlier than the usual date. Given that the Minoan fall was usually dated to 1450 B.C., the gap between cause and effect seemed too large. Another blow landed in 1989 when scholars on Crete found, above a Thera ash layer, a house that had been substantially rebuilt in the Minoan style. It suggested at least partial cultural survival. By 1996, experts like Jeremy Rutter, head of classics at Dartmouth, judged the chronological gap too extreme for any linkage. "No direct correlation can be established" between the volcano and the Minoan decline, he concluded.

Note that the thesis has been refuted on that basis as early as 1989. 1939 is in the 1930s — the decade when the super-eruption came to the forefront. As I think about it, there may be a much earlier origin (mentioned in Zangger's recent book) in the later 19th century, which doesn't exactly mitigate in favor of it.

The rush to find a super-eruption in records has been viewed skeptically by those working in the field, all the way along. Here's an example from nine years ago:

Bronze Age Myths?
Volcanic Activity and Human Response in the Mediterranean and North Atlantic Region
Paul C. Buckland
Andrew J. Dugmore
Kevin J. Edwards
Antiquity Vol. 71 (1997), pp. 581-593.
A first rule of statistics is that the existence of a correlation does not itself prove a causal connection... This paper examines some of the available evidence for these two Bronze Age 'catastrophes', the one real and in need of a calendar date, the other hypothesized on archaeological grounds and dated by a tenuous link through tree rings to an Icelandic volcano... Despite several cautionary comments from both archaeologists (Manning 1988; Warren 1988) and geologists (Pyle 1989; 1990), the 1628 BC date, or one close to it, continues to be accepted (e.g. Michael and Betancourt 1988), without questioning why the effects of the Santorini eruption should be especially recognizable in the ice-core and tree-ring sequences. Large-scale explosive volcanic activity is common on a global scale (Zielinski et al. 1996), and so before accepting the possibility that the Santorini eruption can be recognized by unusual perturbations in the regional records of ice-cores or tree-rings, the case for its distinctive character must be proved.