Reviewing a Possible World-wide Event c. 2400 BC
Barry Setterfield, February 2015
In 1948, it had been noted that destruction by earthquakes, and their consequent fires, was evident at a number of important sites around 2300 to 2400 BC [Schaeffer, 1948]. In Anatolia, the end of the Early Bronze II has been suggested as being about 2300 BC and can be marked by ash layers and wrecked buildings [French, 1967, Mellaart, 1960]. In mainland Greece, the Early Helladic II Age seems to have ended in catastrophic conflagration about the same time [Mellaart, 1968; Weinberg, 1954]. Similar conclusions have been drawn by some concerning the Early Minoan II on Crete [Caskey, 1969; Renfrew 1972a ] while on Cyprus and Malta the Chalcolithic also seemed to close about 2300 BC. [For example, see Renfrew 1972b, 1973].
Likewise, it has been suggested that the Early Bronze III in Syria and Palestine came to an end about 2300 BC [Albright, 1954; Schaeffer 1948]. In this case, Thompson states that there was catastrophic destruction of cities and linked this destruction in time to contemporaneous events in Anatolia and Greece . In Iran and Mesopotamia, the Early Dynastic III seems to have come to a close at approximately that time or a little earlier, with some sites recording destruction, abandonment, or cultural discontinuity [Gupta, 1979; Young, 1969; Lloyd, 1978; Moorey, 1976; Schaeffer, 1948b].
In India, the record from this same interval with the Indus Valley civilizations reveals thick layers of ash at some sites which marked the close of the Pre-Harappan period [Allchin and Allchin, 1968]. At the same time, in neighboring Baluchistan (Pakistan), it is thought that the evidence of burning at many sites may indicate that extensive earthquake damage there had closed these cultures [Raikes, 1964].
In Egypt, the end of the reign of Pepi II at the close of the Sixth Dynasty arguably marked the end of the Old Kingdom and initiated a time of chaos referred to as the First Intermediate Period. The exact dating of this event may be debated, since Baines and Malek  place it as late as 2150 BC, while others place it before 2200 BC. It is possible, though controversial, that the general characteristics of that period with its chaos and destruction may have been sketched for us in the Ipuwer Papyrus [see for example Mumford 2006]. If it was indeed written at this time, it fits in well with a world-wide event sometime in the interval 2500 BC to 2200 BC.
Elsewhere around the world, such as in China, Japan, the Philippines, Thailand, Australasia, the south-western Pacific and the Americas, additional evidence is available that may support this event and its timing [Mandelkehr 1983]. For example, on the Arctic coast of Alaska, the Northern Archaic Tradition ended soon after 2300 BC, while in Labrador, the Pre-Dorset phase of the Paleo-Eskimo sequence has been reported as starting about the same time [Cox 1978]. Even though some of this research is still in a fluid state, the general archaeological evidence nevertheless tends to suggest that some singular event was responsible for all these apparently isolated occurrences. If this is true, then an event on a very extensive regional, if not a world-wide, scale must be envisaged. The series of earthquakes, strong enough to at least partly demolish structures and result in fires that left impressive ash layers over a wide area from the Mediterranean and Egypt across to India and beyond, were not normal seismic events. It is at this point that we need to look to astronomy and geology to give us more data and help us draw some conclusions.
Some Astronomical Evidence.
One potential link in the puzzle comes from ancient astronomical observations. A study of these observations was made and the data collection completed in the early 1960’s by the Government Astronomer for South Australia, George Dodwell. The data included information about the tilt of the Earth’s spin axis, or the Obliquity of the Ecliptic, to use precise astronomical terminology. Dodwell’s analysis of the data indicated that there was a change in axis tilt around 2345 BC. Although the data allow some flexibility in the exact date of the change, this is right in the range of dates in which a potentially catastrophic event occurred archaeologically.
Dodwell died before his extensive research could be published in book form, but his manuscript is still extant [Dodwell 1964]. In it he critically examines the evidence from 66 different observers, including the Arabs, Romans, Greeks, Hindus, Chinese and Egyptians. He did an analysis of the instruments they used, their possible errors and an assessment of each observational series individually. An extensive examination of ancient astronomically oriented monuments, such as those at Tiahuanaco, Stonehenge, and Karnak was also undertaken. In addition, Dodwell made a series of observations at the Adelaide University with equipment similar to that used by many of the ancients. He was then able to determine that the angle of tilt of the earth’s axis, which can be derived from these data, could have an accuracy of up to one minute of arc (with 60 minutes or arc making up one degree).
The outcome was that, as we go back in time, the data revealed a progressive increase in axis tilt that deviated one-sidedly from the standard curve (given by Newcomb’s formula) by five minutes of arc to well over one degree. In other words, the axis tilt was noticeably larger in the past than expected, and the discrepancy got worse the further back in time we go. In any series of observations, there will be a scatter both above and below the true value being measured. The fact that there is a one-sided departure from the predicted curve, rather than a scatter about an expected value, indicates that something had not been taken into account when the standard curve was formulated.
Mathematical treatment of the observational data indicated that the Earth’s axis suddenly changed its tilt in 2345 BC, or thereabouts. The curve of observations indicates that prior to this date a higher axis tilt existed. The observations indicate that the axis tilt then decreased to its present value, stabilizing onto the accepted curve about 1850 AD, rather like a spinning top righting itself after being pushed.
This research may be supported by the study of the chronological movement of the earth’s geo-magnetic pole. The plot of the movement of the magnetic poles reveals that they underwent an abrupt change in direction around 2300 BC [Kawai et al, 1972]. This accords with the Dodwell data and indicates that the core of the Earth is also implicated. Since the Earth has a liquid core, from which its magnetic field originates, then any change in orientation of the spin axis will also produce a compensating change in the core in order to conserve the overall angular momentum of the system. The converse is also true. The implication from these studies is that some astronomical event occurred which changed the Earth’s axis tilt and produced a compensating change in the alignment of the core, or vice versa. The timing of this event closely corresponds with the archaeological data; sometime in the vicinity of 2300 to 2400 BC, give or take a century.
The actual cause of the event, when looked at from an astronomical perspective, can only be considered in terms of the impact of some asteroidal body or bodies. Many asteroids come with a cloud of accompanying debris, so their impacts often leave a main crater plus a series of smaller ones. We see evidence of this sort of thing happening on the inner planets as well as on our own Moon, and the moons of the outer planets. The size and speed of the impacting body determines the size of the crater, and hence the intensity of the accompanying earthquakes and the degree of damage that is done.
There is a further consideration. It is not just the immediate region around the impact which is affected by the event. On Mercury, the Moon, Mars and also Earth, the data indicate that the pressure pulse from such impacts is focused by the planet’s internal layers as it goes through to the core [Schultz and Gault, 1975, Setterfield 2013]. If the pulse is focused by the core and then transmitted on, the result can be massive damage in a region at the antipodal point to the impact. Other regions may also be affected, depending on the angle of impact and various parameters. As a result, even a relatively small impact, whose pressure wave is focused on the Earth’s core, could change the core orientation, and bring about a compensating change in the overall axis tilt. If this is what happened around 2300 BC, as the foregoing data suggest, then we should be able to find geological evidence of the event.
In 2001, geologist Sharad Master from the Impact Cratering Research Group at the University of Witwatersrand, South Africa noticed what may well be a 3.4 km impact structure in the Al ‘Amarah region of Iraq [Master, 2001]. From the local geology, most other methods of formation can be discounted, so impact is the most probable cause. Its suggested age is concordant with the interval under consideration here. In a Conference presentation, Master stated that: “The impact, with the energy of hundreds of Hiroshima-sized nuclear bombs, would have had a devastating effect on the regional environment” [Master, 2002].
There is also the possibility that the Rio Cuarto structures in Argentina are impact craters from the same time as well. There is much more confirmatory information. Benny Peiser of the Cambridge Conference Group [Peiser, 2002] and his colleagues have collected archaeological data from 500 sites in addition to those mentioned here, as well as evidence for other impacts. While these craters play an important part, they are probably only from the debris cloud that accompanied the main object, which probably formed a major crater in the Indian Ocean.
The Major Crater
In 2006 researchers found unusual geological deposits in Madagascar, India and Western Australia. Those at the southern end of Madagascar were typical of the others and were described as “four enormous wedge-shaped sediment deposits, called chevrons, that are composed of material from the ocean floor. Each covers twice the area of Manhattan with sediment as deep as the Chrysler Building is high.” All the various chevrons point to the open water of the Indian Ocean which led to the conclusion that they had been formed by a tsunami over 185 meters high. Tsunamis of those dimensions can only be caused by a cosmic impact [Blakeslee, 2006]. This led them to look for the signs of an impact on the ocean floor.
Near the south-west Indian Ocean Ridge, some 1400 km south-east of Madagascar, lies the Burckle Crater, almost 30 km in diameter. It was found after a search by scientists from several disciplines called the Holocene Impact Working Group, headed by Dallas Abbott . They found that the impact ejecta from the crater contained meteorite fragments, impact glass and spherules, as well as oceanic mantle fragments. Since the impact glasses have no potassium content, they cannot be of continental origin, so they formed in an ocean impact [Abbott, 2006]. The group suspects that the crater originated somewhere about 2800 BC, though a more precise dating is difficult.
This thinking was confirmed in October of 2006 when Dee Breger, director of microscopy at Drexel University in Philadelphia, looked at samples from the chevrons under a scanning electron microscope. She found that tiny foraminifera fossils from the ocean floor had splashes of iron, nickel and chrome fused to their shells. The proportions of those three metals on the shells are the same as those found in chondritic meteorites. Ms. Breger commented that the microfossils appear to have melded with the condensing metals as both were lofted out of the sea by the impact explosion and carried long distances [Blakeslee, 2006].
In order to produce all these results, the impact explosion has been estimated to be equivalent to at least 10 megatons of TNT, or roughly 650 Hiroshima type bombs. This, in addition to the other associated impacts, would certainly lead to the earthquakes, fires, and other conditions that the archaeological data indicate dominated that key interval in history. This also included suspected climate disasters and subsequent changes in weather [Kerr, 1998; Mandelkehr, 1987]. Furthermore, the pressure pulse from such an impact, when focused on the Earth’s core, has the capability of changing its orientation. In order to conserve angular momentum, the angle of the Earth’s spin axis tilt started to respond rapidly, but the response tapered off and did not reach its final equilibrium until 1850 AD. The ancient observations of the Obliquity of the Ecliptic record this response.
There is a distinct possibility that the massive event, dated by Dodwell at 2345 +/- 100 BC, came from the impacts which formed the Burckle and associated craters. These impacts could well have been responsible for the partial decrease of the earth’s axis tilt as well as the catastrophes and climate disasters which interrupted a number of civilizations around the world. Remains of cities and cultures in many places, which indicate massive earthquake activity, ashes from fires, and other sudden devastation, attest to something on a global scale which could possibly be attributed to such an impact event.