Earthquakes
© USGS
Geological map of Alaska showing various exotic terranes.
Geological map of Alaska showing various exotic terranes.
The above schematic of Alaska reveals regions of rock strata that appear to have "accreted" to an original craton. Southern Alaska is composed of fragments in all shapes and sizes, each one telling its own tale. They are all "exotic terranes", formed at different places and times. How they were transported to their present location, and why some are rotated with respect to adjoining terranes is a mystery.
Some exotic terranes arrived from regions on the other side of the world, while others are from nearby locations. They are each quite different from one another in their characteristics, representing strata from many so-called "geologic ages". There are deposits from the Quaternary period lying in proximity to those from the Cambrian and Mesozoic periods. Those epochs represent hundreds of millions of years. If the theory of continental movement is correct, then "collisions" between landmasses took place more than a dozen times in Alaska. However, each terrane is not arranged side-by-side with its neighbor, they are intermixed with each other, as the schematic reveals.
Another puzzling aspect to the terrane lithography is that some of it is oceanic crust, while some is continental. Some terranes appear to be from volcanic islands. Others appear to be the remains of continental shelves from South America. Less than one percent of Alaska is thought to be from the "original" North American continent.
In the Journal of Scientific Exploration, Vol. 14, No. 3, pages 307-352, David Pratt took issue with the theory of tectonic displacement of continental and ocean floor structure. As he wrote: "The classical model of thin lithospheric plates moving over a global asthenosphere is shown to be implausible."
© BAKHTAR NEWS AGENCY
Taliban officials and residents survey the damage to homes in Afghanistan's eastern Paktika province after a major earthquake.
Taliban officials and residents survey the damage to homes in Afghanistan's eastern Paktika province after a major earthquake.
Pictures show landslides and ruined mud-built homes in eastern Paktika province, where rescuers have been scrambling to treat the injured.
In remote areas, helicopters have been ferrying victims to hospitals.
Taliban leader Hibatullah Akhundzada said hundreds of houses were destroyed and the death toll was likely to rise.
Ibu volcano
Mount Bulusan
This video will discuss these volcano related news stories, as told and analyzed by a volcanologist.
The quake was at a depth of 616 km (383 miles) and struck about 111 km south-southwest of Tarauaca, Brazil, EMSC said.
(Reporting by Nishit Jogi in Bengaluru; Editing by Tom Hogue)
Source: Reuters
Residents left their homes as tremors shook buildings.
Buildings were damaged by the earthquakes, with cracks seen in walls.
Citizens have been advised to not to travel unless necessary.
Authorities are assessing the extent of damage caused.
Stephen Holtkamp, duty seismologist with the Alaska Earthquake Information Center, says this is a pretty typical sequence for this region.
"We can expect the aftershock sequence to continue for a few days," said Holtkamp. He also said there is a low chance, about 3 to 5 percent, of a larger earthquake happening in the same area.
There has been no tsunami risk with these earthquakes. Holtkamp says these earthquakes are too deep to create a tsunami. "In order for a tsunami to be generated, it (an earthquake) needs to move the sea floor up and down," said Holtkamp. "There's 65 miles of rock between where the earthquake happened and the water," Holtkamp said.
Davidof Island is in the Rat Islands. The first quake was recorded 36 miles southeast of Kiska Volcano and 55 miles west of Semisopochnoi Island.
Comment: Details of the other two:
- Shallow magnitude 6.4 earthquake recorded west of Macquarie Island
- Magnitude 6.2 earthquake - South Pacific Ocean off Tonga
A magnitude 6.0 earthquake near Neiafu, Vava'u, Tonga, was reported only 14 minutes ago by the German Research Centre for Geosciences (GFZ), considered one of the key international agencies that monitor seismic activity worldwide. The earthquake occurred at an intermediate to considerable depth of 237 km beneath the epicenter early morning on Sunday, June 5th, 2022, at 2:07 am local time. The exact magnitude, epicenter, and depth of the quake might be revised within the next few hours or minutes as seismologists review data and refine their calculations, or as other agencies issue their report.
© Getty Images
Magnitude 6.4 earthquake recorded west of Australia’s Macquarie Island
Magnitude 6.4 earthquake recorded west of Australia’s Macquarie Island
A magnitude 6.4 earthquake has struck the west of Australia's Macquarie Island.
The island, about 1,600km southeast of Tasmania, felt the earthquake late on Saturday night.
No damage has been reported so far.
The earthquake had a depth of 10km and is believed to have been felt shortly after 11pm.
A 6.9 magnitude earthquake also hit the island two weeks ago, briefly placing Australia on tsunami watch.
Comment: Update June 24
The New Arab reports: