Friday, May 13, 2011

The Volcanic Explosion at Santorini and the Destruction of Minoan Crete

The fall of Minoan Crete, and for that matter Mycenae, are a mystery. There is evidence of fire at both locations as if they were attacked and burned. Was this the so called Dorian invasion or something else?

An interesting piece to this puzzle is the eruption of the Santorini Volcano, which had a significant impact on the region, especially Crete. Its part in the destruction of the Minoan civilization is still being debated, so I’ll let you can form your own opinion after you’ve seen the facts.

Let’s start with the geography. The image below is a satellite view of Santorini (known as Thira in antiquity). 

The existing islands are actually the rim of the crater of an active volcano. The volcano collapsed during an eruption circa 1525 B.C. and has been re-building itself since that time. The center island, Nea Kaimene, is made up of new lava deposits as the volcano rebuilds its cone. The island now reaches about 400 feet above the surface of the Aegean. I have marked the location of known Minoan settlements on Santorini showing that Thira was a Cretan satellite during the Minoan Period.

The first of these settlements was accidentally discovered in 1859 when part of Thirasia was being mined for material to be used in the construction of the Suez Canal. As the construction teams worked to cut away layers of ash, they exposed the ancient stone walls.

The next photo is one I took when I was in Santorini last September. I’m standing on Thira Island and you can see Nea Kaimene at the left in the foreground and Thirasia Island behind it in the distance.

To get a sense of the magnitude of the explosion of the Santorini Volcano, we can use the August 27th, 1883 eruption of the volcano Cracatoa in Java as a guide. When that volcano exploded, windows were rattled at a distance of 100 miles. A column of ash rose seventeen miles into the atmosphere and there were a series of four violent explosions resulting in the collapse of the cone. The third of the four explosions was the loudest noise ever recorded on earth – heard on the Isle of Rodriquez  3,080 miles away. Wind-born ash fell over a very wide area, including 17 inches at Port Alfred South Africa, 4,500 miles away. We have excellent data on the spread of the ash cloud because of the records of ships in the area. For example, the ship Tweed recorded seven inches of ash on her decks at a distance of 370 miles. The Cracatoa eruption was accompanied by a Tsunami which generated fifty foot waves and devastated all coastal developments and towns in the region.

I have provided the Cracatoa story to make a point.

The Santorini eruption was significantly (4 times) larger than Cracatoa and was the largest volcanic eruption on earth in the last ten thousand years.

Crete is only 68 miles from Santorini.

Now we know that in the Late Minoan 1B period, circa 1500 B.C, the northern coast of Crete (east of Knossos) was wiped out. There is archaeological evidence of ash deposits in during this period and similar deposits have been found in the seabed of the Aegean. Similarly, we know that the Minoan settlements on Santorini were buried under ash in the Later Minoan 1A period, perhaps 10-20 years before the Cretan deposits. How can this be explained?

The evidence points to a two stage eruption: the first dropping pumice over a wide area and the second, years later, dropping ash as the volcano collapsed, causing a Tsunami and possibly an earthquake.

Some of the structural damage to Northern Crete could not have been caused by ash or Tsunami, only by an earthquake. How do we then reconcile the eruption with the fire damage? The burned remains pre-date the volcanic eruption because they were buried in the ash, so the Minoans must have been attacked previous to the eruption or an earthquake must have preceded the eruption and caused the fire. The ash probably made Northeastern Crete uninhabitable for a time because of the destruction of plant life.

The tsunami itself would have been an incredible force at 75 feet high, reaching Crete twenty minutes after the explosion on Santorini at a speed of 200 miles per hour. As far as the earthquake goes, we have too little data to positively relate a Santorini earthquake to the damage in Crete.

The image below shows distances from Santorini to various places in the region including Egypt. This gives a sense of the devastation that must have visited the surrounding islands.

We have to conclude that Crete was attacked and burned by some outside agency prior to the devastation caused by the Santorini Volcano, but the eruption probably destroyed any Minoan attempts to restart their civilization and opened the door for the Mycenaeans to occupy Crete and end the island civilization for good.

1 comment:

Brandon said...

i stumbled on this with and i wish it would let me like it twice.