NESKOWIN BEACH OREGON
Drowned "Ghost" Forest
1700 Cascadia Earthquake
The drowned "ghost" forest at Neskowin Beach, Oregon.
The ghost forest at Neskowin Beach, Oregon, was unknown until 1998 when a winter storm pulled back a layer of sand from the beach and revealed more than a hundred stumps of Sitka spruce. How was it that a forest of Sitka spruce was below the level of daily ocean tides?
The answer came when it was realized that another mystery could be solved by determining when the deaths of the trees in this forest had occurred. Growth rings showed that they had died during the winter months of 1700. During those same winter months, a series of giant sea waves had swamped the shoreline of eastern Japan. But no major earthquake had yet been tied to the timing of the waves.
Written records in Japan indicated that the first wave had arrived around midnight (Japan time) on January 28, 1700, and that the series had lasted about twelve hours. From the size of the waves, the earthquake that had produced them must have been one of the largest in recorded history. But there were no written records of such strong shaking anywhere around the Pacific. And so it must have originated along a shoreline were written history had not yet begun.
Some sleuthing showed that it must have been an earthquake in Cascadia, that section of North America where the Juan de Fuca Plate is subducting beneath the North America Plate and where major earthquakes are produced. Accounting for the time of passage of the sea waves across the Pacific Ocean, the earthquake must have occurred about 9 am on the morning of January 26, 1700.
It would have been a magnitude-9 earthquake, similar in size to the earthquake that occurred along the southern coastline of Alaska in 1964 or along the coast of Sumatra in 2004, which generated giant sea waves that drowned more than 200,000 people, or that occurred on March 11, 2011, in the Tohoku region of western Japan that drowned nearly thirty thousand people and damaged nuclear reactors.
During each of these large subduction-related earthquakes, coastal areas suddenly dropped down several meters. A similar thing happened in Cascadia in 1700: A forest of Sitka spruce next to the coastline was suddenly dropped beneath sea level, the saltwater flooding the forest and killing the trees. The area was later covered by sand and revealed, as already stated, by a storm that pulled the sand away and revealed the stumps of the ancient forest.