Radiocarbon dating applied to Dynastic Egypt has been successful, see Bronk Ramsey 2010. However when applied to Lower Egypt and in particular Hyksos Avaris and to the date for the eruption of Thera on the Aegean island of Santorini there are large but fairly consistent discrepancies.. The dates obtained are always about 100 years higher using radiocarbon dating..
The Thera eruption had a dense rock equivalent (DRE) of over 60 cubic kilometres, A volume of ejecta of 100 cubic kilometres. An Explosivity Index of 7. Ash was ejected into the stratosphere over 12 km above the Earth's surface. There had been previous minor eruptions extending back centuries before the Plinian eruption.
REMNANT OF THERA AFTER ERUPTION 1620 OR 1520 BCE
ARCHAEOLOGY
Minoan Neopalatial Periods for Crete and Aegean
MM IIIA 1700-1640
MM IIIB 1640-1600
LM IA 1600-1480
LM IB 1480-1425
Ceramic evidence indicates the eruption of Thera was in the LM IA period. The LM IA period continued for a little time after the eruption and a longer time before the eruption. When a date for the eruption is agreed upon the LM IA period should be sub-divided into LM IA1 and LM IA2 periods. The Thera eruption is a major event for the Bronze Age Middle and Near East chronology.
Pumice from Thera
The pumice from Thera numbering over 400 pieces has New Kingdom provenance.. That is no earlier than King Ahmose reign 1551-1526. The Thera pumice at Avaris from Thutmosid phase C2 ( 1430 BCE) may be a collection of abrasive material stored for later use. Pumice found at Tell el-Ajjul in the Gaza strip,is from Horizon 5 and this correlates with phase D1.2 at Avaris toward the end of the reign of King Ahmose.and the Mid Bronze/ Late Bronze transition.
FRESCO FROM THERA PRIOR TO ERUPTION 1620 OR 1520 BCE
Middle East correlation of Minoan civilization
Several sites in the Middle East have Minoan frescoes, that is true frescoes painted on wet plaster.
At Alalakh, Tell Atchana in Turkey, Minoan frescoes have been found including sprays of leaves typical of LM IA frescoes, in the palace of Yarim Lim III. There is controversy about the date of the destruction of Alalakh Stratum VII by the Hittite Hattusili I providing a teriminus ante quem for these frescoes. The Middle chronology says 1648, the short chronology 64 years later in 1584 and lately Bietak has suggested about 1560 BCE correlating with the Avaris D/3 transition to D/2 phase. There is no bichrome ware in stratum VII while Stratum VI does. The successor of Hattusili I was Mursili I who.conquered Babylon, By the short chronology 1531 BCE and by the Middle chronology 1595.
Tel Kabri in Western Galilee provides another contact with the Minoans. The frescoes here belong to Palace 3 and are of a similar date to those at Alalakh. Frescoes of irises are typical LM IA1 date prior to the Thera eruption.
Tell el-Ajjul in the Gaza strip has produced pumice with Thera fingerprint. The earliest is from Horizon 5. the Middle Bronze to Late Bronze transition. Radiocarbon dating of 5a pumice is mid
16th Century. NO pumice was found in Hoirizon 6. (Fischer 2009).. Pumice would have been swept to the coast by the tsunami and massive tidal surges after the eruption. Little time between the eruption and appearance of pumice on the coast should be allowed.
IRIS FRESCO FROM TEL KABRI LM IA DATE
After Neimeier
Egypt correlation of Minoan civilization
Dynastic Egypt has been well characterized. Radiocarbon dates have broad agreement with Archaeological dates (Bronk Ramsey 2010). King Ahmose dates by radiocarbon are 1570-1544 BCE only 18 tears earlier than the currently accepted dates. King Ahmose was a late contemporary of the Hyksos King Apepi of Avaris (c.1585-1545) and of the last Hyksos King Khamudi (c.1545-1535).
There is literary evidence for the contemporaneity of King Kamose the predecesssor of King Ahmose and Apepi of the Hyksos. The date for the expulsion of the Hyksos from Egypt is probably 1540-1535. At least some of the Hyksos including King Khamudi may have fled to Jericho. Two scarabs of Khamudi have been found there. A destruction level for Jericho stratum IVC is at the end of the Middle Bronze Age (MBIII). In addition radiocarbon dates for this destruction are 1601-1566 and 1561-1524 in strong agreement with the reign of Ahmose.
The expuslion of the Hyksos was recorded by Ahmose son of Ebana at his tomb.Later he went to Nubia and was not in Egypt for a period after the expulsion. He records a later campaign with Amenhotep I (1526-1505).For Avaris see Bietak and Forstner Muller auaris.at 2003- present.
KING AHMOSE FOUNDER OF THE 18TH DYNASTY
EXPELLED HYKSOS AND ISRAELITES FROM AVARIS
Ahmose tempest stela.
King Ahmose would not have erected a 1.8m stela at Karnak except for a notable event, " then the sky comes in a tempest..... with darkness in the Western region". The King was in Dendera at the time of the darkness and the storm, He then moved back to Thebes about 70 km away, This massive tempest was associated with the Thera eruption. The prevailing north west wind would have swept dust and ash directly toward Egypt,creating a massive disturbance in the troposphere.
A date of 1530-1520 BCE is likely.See Ritner and Moeller 2014..
AHMOSE TEMPEST STELA FROM KARNAK. IT WAS NOT A TEMPEST
AS INDICATED ON THE STELA THE DARKNESS COVERED
A WIDE GEOGRAPHIC AREA
Judahite plagues.
The five pastoral Judahite tribes associated with the plot to kill Joseph were assigned land in Goshen east of the Pelusiac Nile when they came to Egypt about 1625 BCE. (Genesis 47:1-3)..They were to remain there until after the death of Ramesses II in 1213. The ninth plague says " a thick darkness in the Land of Egypt for three days," Exodus 10:22 and the seventh plague, " so there was hail and fire mingled with the hail,such as there was none before in all the land of Egypt since it became a Nation." Exodus 9:22-23. These are folk memories carried down the years, retained because it was such a memorable event. The Judahites lived in the Egyptian delta region, they were witnesses to the results of the eruption of Thera., Falling tephra would be the fire they witnessed in the sky.Most of this tephra would have burned in the atmosphere before reaching ground level. Later these memories would be used for another purpose..
RADIOCARBON DATING
Thera
Olive branches from Thera have been dated to 1627-1600 BCE (Friedrich 2012). Mean of 1613 BCE.
A review (Manning 2014) of recent Carbon 14 dating for Thera
gives weighted averages of 3345 BP +/- 8 years for 25 samples. The likely dates are 1635-1615 BCE.
Tell el-Daba (Avaris Egyptian delta).
A comprehensive radiocarbon testing regime for Tell el-Daba was carried out.( Kutschera 2012)
A difference of 100-120 years was found between Archaeological dates and radiocarbon dates. The radiocarbon dates were consistently higher.
Radiocarbon dates use Bayesian Statistics that is "inferential chronology" based on existing chronology from Archaeology to arrive at their result. However this has worked well with Dynastic Egypt using short lived material from Upper Egypt (Bronk Ramsey). The science works well in other areas. This indicates regional aberrations as the cause of the anomalous results.
RADIOCARBON. REGIONAL VARIATIONS AND VOLCANIC ACTIVITY
Production of Carbon14. Inhibition of neutron activation of Nitrogen 14.
Volcanic activity at Thera had started long before the Plinian eruption. Dust and ash had drifted into the upper troposphere and lower stratosphere probably for centuries before the LM IA eruption. The prevailing north west wind took the dust to areas East and South of Thera.
Production of radiocarbon depends initially on the activity of "cosmic Rays" actually protons.
PROTONS PRODUCE NEUTRONS BY COLLISION WITH NUCLEI
FREE NEUTRONS DECAY IN LESS THAN 15 MINUTES
If collision with a receptive nucleus does not occur within the time neutrons decay as above..
NEUTRONS ACTIVATE NITROGEN ATOMS
Neutrons have a range of less than 3 femtometres for interaction with the nucleus of a Nitrogen atom. Competitive inhibition of Neutron activation occurs in the presence of volcanic dust. Interaction of neutrons with oxygen, sodium, potassium, aluminium and silicon nuclei is likely. Only a small fraction of neutrons interacting with volcanic dust rather than Nitrogen atoms is required. The error is 100 years in a total 3500 years, an error of 3%. The C14/C12 ratio is less than the 1.5/trillion in presence of volcanic dust
The calculation of the radiocarbon date is based on;
t = 8267 ln (N0/N) years
The value for N0,, the initial level of C14, is based on the assumption that the ratio of C14 to C12 is constant. In the presence of volcanic dust this is not true. The calibration curves used to calculate the results are invalid when applied to areas affected by volcanic ash. The assumed C14/C12 ratios are skewed to give higher values for radiocarbon years. A lower level of C14 is present in the initial sample perhaps a ratio of 1/trillion. This requires validation using the radiocarbon dating program.. This local variation will result in a lower initial level of radiocarbon than the assumption of constant values used to calculate t and hence higher values for radiocarbon years.
Another variable is the millenial time scale changes in cosmic ray flux of 1.5 to 2 fold. The cosmic ray flux and production of 14C is not constant as once thought. However the time frame is long and probably not applicable to short lived plants.
Attenuation of neutron activation inhibition by volcanic dust.
There is a distance and direction from the epicentre of the volcanic eruption where the inhibitory effect of volcanic dust on neutron activation stop. This appears to be about 1000 km in the case of Thera and radiocarbon dating for Egypt. The prevailing North West wind direction must also be taken into account.
1000 KM ATTENUATION LIMIT FROM THERA
Avaris Lower Egypt 820 km Neutron activation inhibited
Thebes Upper Egypt 1400 km No effect
Babylon Iraq 1700 km No effect
Alalakh Turkey 900 km Neutron activation inhibited
Jerusalem 1000 km Slight neutron activation inhibition
Upwelling of Carbon from Ocean deep
Most of the free Carbon is stored in the ocean 38100GtC (Gigatons carbon) compared with 750 GtC in the atmosphere. Decay of stored C 14 has occurred to a much greater level than the 3600-3500 years since the eruption. However the disturbance of the ocean would have been at the time of the Plinian eruption rather than a pre-existing effect. There is some doubt whether this disturbance would have affected uptake of radiocarbon CO2 before the time of the eruption.
CARBON CYCLE MAJOR STORAGE OF CARBON IN OCEANS
CONCLUSION
Stratigraphy and pottery seriation are still the "gold standards" for chronology of pre-literate societies. However radiocarbon dating has come of age. The small differences between Archaeology and Radiocarbon will succumb to advances in Technology and knowledge.
At this stage the 16th Century date for the Thera eruption and the expulsion of the Hyksos should be accepted unless evidence to the contrary of an incontrovertible nature comes to light. Sugggested dates are 1540 BCE for the Hyksos expulion and 1530 BCE for the Thera eruption, Both +/- 5 years.
The Late Minoan IA period should be subdivided into pre and post Thera eruption when a date for this eruption is accepted. The Thera eruption was a major event both for the nearby inhabitants and for the chronology of the Middle Bronze Age to Late Bronze Age transition.
DEDICATION
To Manfred Bietak the doyen of Tell el-Daba Archaeology who has worked so long and so hard to unravel the Archaeology of Tell el-Daba and the Middle Bronze Age Chronology conundrum.
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