Santorini is an island in the southern Aegean Sea, about 200 km (120 mi) southeast of Greece's mainland. It is the largest island of this small, circular archipelago that bears the same name and is the remnant of a volcanic caldera. The municipality of Santorini comprises the inhabited islands of Santorini and Therasia and the uninhabited islands of Nea Kameni, Palaia Kameni, Aspronisi, and Christiana.
Santorini is essentially what remained after an enormous volcanic explosion that destroyed the earliest settlements on a formerly single island, and created the current geological caldera. This giant, central, rectangular lagoon is surrounded by steep cliffs on three sides. The main island slopes downward to the Aegean Sea. On the fourth side, the lagoon is separated from the sea by another much smaller island called Therasia. The lagoon is connected to the sea in two places, in the northwest and southwest.
Santorini is the most active volcanic center in the South Aegean Volcanic Arc. What remains today is chiefly a water-filled caldera. The region first became volcanically active around 3–4 million years ago. The island is the site of one of the largest volcanic eruptions in recorded history: the Minoan eruption (sometimes called the Thera eruption), which occurred some 3600 years ago at the height of the Minoan civilization. The eruption left a large caldera surrounded by volcanic ash deposits hundreds of meters deep. Some researchers believe that his eruption may have led indirectly to the collapse of the Minoan civilization on the island of Crete, 110 km (68 mi) to the south, through a gigantic tsunami. Another popular theory holds that the Thera eruption is the source of the legend of Atlantis.
For decades, scholars have debated whether the eruption of the Thera volcano in the Aegean more than 3,500 years ago, brought about the mysterious collapse of Minoan civilization at the peak of its glory. For Minoan Crete, scientists see direct and indirect consequences. One perspective speculates that towering waves from the eruption that hit Crete were up to 15m high, smashing ports and fleets and severely damaging the maritime economy. Thera's outburst also produced dense clouds of volcanic ash extending over a vast region, thus, crippling ancient cities and fleets, setting off climate changes, ruining crops and sowing wide political unrest. Still other scientists believe that the eruption occurred more than 150 years earlier and would have had little impact on the Minoan civilization. As doubts continued to rise about this linkage, scientists found more evidence suggesting that Thera's eruption had been unusually violent and disruptive over wide areas. Scientific maps drawn in the 1960s and 1970s showed its ash as falling mostly over nearby waters and Aegean islands.
In the mid-1960s, scientists dredging up ooze from the bottom of the Mediterranean began to notice a thick layer of ash that they linked to Thera's eruption. By the 1990's, however, the affected areas had been found to include lands of the eastern Mediterranean from Anatolia to Egypt. Scientists found ash from Thera at the bottom of the Black Sea and Nile delta. They tracked it over thousands of square miles. Such clues helped geologists estimate the amount of material Thera spewed into the sky and the height of its eruption cloud, main factors in the Volcanic Explosively Index. The volcanic explosivity index (VEI) was devised by Chris Newhall of the US Geological Survey and Stephen Self at the University of Hawaii in 1982 to provide a relative measure of the explosiveness of volcanic eruptions. Its scale goes from zero to eight and is logarithmic, so each unit represents a tenfold increase in explosive power.
The world map might look differently had the Greek volcano Thera not erupted 3,500 years ago in what geologists believe was the single-most powerful explosive event ever witnessed. Thera didn't just blow a massive hole into the island of Santorini – it set the entire ancient Mediterranean onto a different course, like a train that switched tracks to head off in a brand new direction.
Resources:
Santorini……….From Wikipedia, the free encyclopedia
Santorini ancient Greece
Geological history How the Eruption of Thera Changed the World, by Heather Whipps
In order to claim a find for this cache, please e-mail me the following:
1) Give GC santorini,......A view to Atlantis???
2) List #in party & geocacher names
3) Based on known scientific calculations of VEI, what magnitude VEI has been assigned to Santorini?
4) Name 2 other eruptions that have been assigned a similar VEI to Santorini
5) In your opinion, how do you believe the Thera volcanic eruption ‘did cause/did not cause’ the end of the Minoan civilization and why
6) At GZ, estimate the steepness of the hillsides in degrees (from 0 degrees for horizontal to 90 degrees vertical), describe the colour of the rocks from sea level to to top of the hillside, and tell me what you noticed about the symmetry of the caldera
7) post (with your log) a ‘scenic’ photo of the journey of your group (or your GPSr) on the way up or back down
BONUS: tell me what number is painted on one of the steps near the top (please DO NOT include this number in your cache log)
congratulations!!!.......FTF.......marshall.md