25/2/25
A brief history of Alfred Wegener’s continental-drift hypothesis in 1911, He looked at the coast lines of Africa and South America and saw that the fit parallels with identical limestone deposits. British coal deposits and American ones are similar. Glossopteris fossils found everywhere including Africa , S America, India and Australia.
1890 with discovery of Radioactivity and the heat of the earth crust, which was floating on denser material. Lighter continents could thus move across the heavier ocean basin.
In 1940 during the war it was realized that the sea floor was covered with canyons and trenches and volcanoes. Radio dating estimated the earth was 1.6 billion years old. Ships laying cables from Europe to American saw the mid Atlantic ridge. In 1959 these were recognized as places of hot rock and magma. and were spreading and rifting.
1959, a magnitude 7.5 earthquake popped off right near Yellowstone National Park. It caused a great deal of damage, including the nation’s biggest recorded rock slide.
1964 Alaska’s Good Friday Quake . A magnitude 9.2. the second most powerful in world history in Alaska. devastated the southern half of the state and killed more than 130 people. A day later, George Plafker, a geologist with the U.S. Geological Survey, arrived to investigate. The guess was that this had occurred about 10 miles under the surface. His fascinating scientific detective work in the months that followed helped confirm the then-controversial theory of plate tectonics.
Much of north Alaska tundra in the north and south is boreal forest thick with conifers, willows and beaches, hard to find outcrops of rocks for geologists, the south had more rocks to study.
1940 Arthur Grantz (1927 to 2021)had explored Alaska with packhorses to do geological fieldwork in 1945.Reuben Kachadoorian a geological engineer was part of this team.
1963 Christin Madsen a teacher and had studied anthropology got a job in Alaska teaching with 2 other teacher elementary school but wanted to be in a 1 class schoolhouse so she was sent to island village of Chenega. The 14 children in her class had mostly Russian names and some Russian blood. She was paid $5000 a year a lot of money at the time. This village was based on hunting and fishing but was more tied to the sea than other tribes. Halibut began in late winter, Seal hunting in May and then Salmon (the main part of the diet) in early summer. Shellfish the whole year. The Russian Orthodox Church has left its mark
1741 a Danish captain in charge of a Russian naval expedition came to the William Sound. 1778 Captain Cook on his third and final voyage also came on a quest for the Northwest Passage. Human settlement in the area dates back to 4,500 years ago.
The Russians trades were interested in pelts of sea otter and other animals, which fetched a high price in China and virtually enslaved the natives, by holding women hostage. Alaska has an annual average of 22 feet of snow. Corpses were stored till spring to be able to bury.
1867 Henry Seward US Secretary of State bought Alaska for $7.2 million in 1959 it became the 49th State.
1897 of 4000 adventurers who landed in Valdez only 1 in 10 got near the Yukon or Klondike.
Valdez was built on unconsolidated sediments and if water came up this became like quicksand. 1907 The road was completed to Valdez and it was the main port of supplies to the interior and ice free all year. The population there exceeded 5000 exclusively white. Rich copper deposits in the Wrangell Mountains. Fort Liscum was an army base here. There was a regular horse drawn sled service to Fairbanks. Gold mining went into decline by the 1930s. By 1961 there was still enough commercial fishing to support a cannery.
George Plafker did a major a civil engineering , but did a course in geology and was attracted to to that by his teachers. His mother died and he was brought up and the Hebrew National Orphans Home in Yonkers with another 184 boys an orthodox institution for boys from 6 to 18. The geology class was taken out into Manhattan parks to study the bedrock there every week. 1949 he went to work for the Army Corps of Engineers in Sacramento California. The after he married went on the US geological survey in Alaska which is twice the size of Texas.
Many of Alaska's mountains are volcanoes active and extinct. 50 of these have been active in the last 2 and half centuries. It is part of the Pacific Ring of Fire. This included Chile Ecuador ,New Zealand , ,Indonesia with Krakatoa erupted in 1883 and Pinatubo in Philippines in 1991.Also Japan and the Siberian Coast of Russia.
Geologist are put down by a plane and if the pilot crashes there is nobody to identify where they are They had army tents but would got without poles which they would cut from willow branches. They had military K-rations that were 10 years old. The spent summer in Alaska and processed their notes in winter back at the Menlo Park office back at his family.
He now worked for Chevron oil in Guatemala as he earned far better. Then Bolivia, where he saw drop stones that come from glaciers. Chevron now pulled out as they could get all the oil needed from the Gulf of Mexico for $3 a barrel and Saudi for $1.50 to get out of the ground. He could get work with Shell in Libya.
By 1954 the population of Alaska was 250,000 including 40,000 natives. Half the population lived in Fairbanks. and Anchorage which was the hub of the railway line from 1920s. In 1951 A proper airport was build in Anchorage.
1935 with the New Deal program over 200 families were brought to Palmer, Alaska from the mid West. During the Cold War millions were spent on airfields. In Prince William Sound, Cordova became the centre of salmon fisheries.
Tourism grew and the military was a strong economic engine.
Madsen teaching in Chanega had to teach 180 days in the year including Saturdays because as soon and the salmon season started the school year would end. The school house would also be the movie house for the whole village on Friday nights. TV never came till the 1970s. The Alaska Steamship company converted Liberty ships to cargo carriers for regular runs to Seattle.
Mount Fairweather in the highest peak on the coast 15,525 feet. 1906 San Francisco is on the San Andreas Fault which moves horizontally, by 20 feet the Fault which is 810 miles long. 7% of world earthquake energy release in a year is in Alaska. In 1899 an earthquake shattered the Muir glacier that sent down so many icebergs that they blocked the bay for a decade.
1964 Valdez was wiped out, the port vanished a half a minute after the shaking started as the land turned into liquid.
Cordova badly damaged and Whittier and Seward ablaze. About 2 dozen Chenagans were missing. Land was rising or falling 3 or 4 feet with every quake wave. With uplift there were thousand of dead fish covering the surface, red snappers, if fish rise to the surface too fast their swim bladders burst. There were places where heavy equipment had moved hundreds of feet , hillsides stripped bare of vegetation and ton boulders found halfway up slopes. Clocks had stopped at 5.36pm, the shaking lasted 4 to 5 minutes, landslides blocked roads and bridges collapsed. Port Alberni 25 miles inlet , residents knew that the first wave would by followed by other and evacuated to higher ground without loss of life, but the town and stores were lost. The main highway was blocked by collapsed land and eventually the highway dept. brought loads of sand to fill it in. Villages on bedrock remained intact despite damage to homes. Undersea cables had survived.
Waves even reached the Antarctic peninsula.
Charles F. Richter had developed the Scale with Beno Guttenber in 1930.
1960 they US government wanted a standardized Seismology network funded by the military DARPA could also detect nuclear weapon tests.
Acorn barnacle Semibalonus balonoined lives in cold oceans. In 1830 Charles Thomson a British army surgeon biologist understood these. They are crustaceans like shrimp but the larvae swim off and find a rock and stick to it between the high and low tide. The barnicles would have died but left a mark where the high and low tide were., and thenext generation of barnacles a year later also left a mark to compaire to the old line. People who live by the sea know the tides and could expain what had altered.. At Tatitlek high tide was 6 foot lower than before the quake. The boat captain said sid there were drift wood piles 8 foot above where they were. They concluded that this quake had released twice the energy of the 1906 S. Francisco one. No report was given on the Anchorage nuclear missiles. some river beds hardly flowed for a week. as perhaps fissures had swallowed the water
Madsen decided to leave Alaska and would return to her parents in Long Beach and decide on her next stage of life.
President Lyndon B Johnson immediately declared a state of disaster ad allocated money and eventually it cost $310 million. The army corp. worked but all construction has to be done in summer. By 1967 the New Valdez had the population that the Old Valdez had befor the quake.
The Chenege became a diaspora tribe in different towns. Valdez the whole town was rebuild safe inland.
Plafker now returned to Alaska and he knew what the area geologically was like before the earthquake. He tried understanding why so much land had been uplifted and so much had subsided. There was a "hinge" line zone where there was no uplift or subsidence. Montagne Island had moved 60feet to the southeast. so there was also lateral movement. Like pulling pizza dough the crust gets thinner in the middle, like the lower land.
Rocks contain a permanent record of the orientation of magnetic field to the magnetic pole at the time of formation. The wandering and even polar reversal. The idea was to look at magnetized rocks of the world determine their age and put together a time line of when their magnetic field reversed. he data proved that Continental Drift was real. Thus you have polar reversal.
Plafkers task was to figure out what had happened below Alaska the mechanism that caused this uplift and subsidence. They also wanted to understand the seismic signature of earthquakes versus atomic bomb tests. The San Andreas fault is about 1,200 km long. The oceanic crust slid underneath the continental crust. Plafkers work is known as the theory of plate tectonics. Frank Press suggested the he look at the 1960 earthquake that struck Chile to find a confirmation of the oceanic crust colliding with the continental one. it lasted 10 minutes and had a bigger tidal wave. The continents are moving and the earths crust are moving.
Designing structures in earthquake zones were made stricter. The size of the slip can be determined by the size of the seismic waves.. 3 years after his work in Chile, Plafkers got his doctorate.
1968 oil was discovered on the north side of the Brooks Range, near Prudhoe Bay.
1971 Alaska Claims Settlement Act passed by Congress the they relinquished their claim to State land and the native population received 40 million acres outright.
1989 Exxon Valdez supertanker ran aground in the prince William Sound. This brought a big population back to Valdez to the clean up operation. The Trans Alaskan Pipeline runs from Prudhoe Bay to Valdez a distance of 800 miles. At its peak it sent 2 million barrels a day in the late 1980 and that is down to a quarter today.
However major Megathrust quakes happened here only once in 6 to8 hundred years.
Other books I have read on Alaska and written on this blog.
Inside of Time: My Journey from Alaska to Israel by Ruth Gruber2002
John Muir The ice that started a fire by Kim Heacox 2016 212pg