Skip to comments.Sumatra coastal cave records stunning tsunami history
Posted on 12/11/2013 8:05:53 PM PST by LeoWindhorse
A cave on the northwestern coast of Sumatra holds a remarkable record of big tsunamis in the Indian Ocean.
The limestone opening, close to Banda Aceh, retains the sandy deposits washed ashore by huge, earthquake-induced waves over thousands of years.
Scientists are using the site to help determine the frequency of catastrophes like the event of 26 December 2004.
(Excerpt) Read more at bbc.co.uk ...
krakatoa (further East)
I’m guessing that they happen more often than some folks would like to think.
The seafloor around the Hawaiian islands are littered with the remains of massive ancient landslides that produce tsunamis.
They are surprised? This place has earthquakes going off like a percolator.
Living on a beach, I always have tsunamis in the back of my mind. It is my opinion that I am not so subject to a killer tsunami, as I am blocked from the open Pacific by other islands of the Philippines. I am, however, affected by earthquakes, less then 50 km from me. Since the big 8+ quake last month, we now have several small (mag 4 or less) almost every day. Very few are even noticed, and I have seen no surge in waves. The quakes are on Bohol, a large island that I can see from my beach.
If any FReeper is an authority on the subject, I would welcome any opinions.
Pretty cool. Thanks for posting.
MOVE UP THE HILL a bit .....
it is thought that these gigantic landslides might have produced Iminami’s ; super size locally generated wash backs caused by such collapses . The displaced ocean surge back to the shore and has left traces of marine debris to over 1000 ft. in elevation . A space object hit in the ocean would also produce such an iminami .
Aftershocks, and for that matter foreshocks are very common with big earthquakes. I was in a 7.5 in Mexico City (1957?) and as I lay in bed, for weeks after I could feel little rumbles, sometimes several a day. I was in the Virginia earthquake last year. Was sitting on my bed and the wall oposite me started to vibrate and shake for about 15 seconds. At first I thought it might have been a distant bomb/explosion, but when no sound came thought earthquake. At least once in the next several days I felt a faint vibration while sitting, and once saw the surface of a glass of water start to shimmer. Didn’t feel anything then but an aftershock of 2.0 was reported later. Leave a bowl of water out if you want to track the minor ones.
Eight+ is plenty big, but another big one is possible. Google New Madrid Earthquakes, 1811-12 for more info. There were at least 3 8+ earthquakes and many other 7+ over a 4 or 5 month period.
MOVE UP THE HILL a bit
I like living on a beach, as it is still somewhat new for me.
My first 60+ years were hundreds of miles from any sea.
I can gain several hundred feet within 5 to 10 min if I have some advanced warning.
Oh, I did read up on ancient tsunamis. Some traversed the Atlantic all the way from Africa to North and South America.
They have had a huge impact on earth’s population and landscape.
By the way, during my first trip to Asia, 1999, I visited Phuket, Thailand, as well as the resort islands to the north that were later devastated by the Indian Ocean tsunami.
Grab the family and run.
clear a nice wide ,direct path straight up hill . Have an ‘essentials ‘ grab&go pack . Know where you documents are and be sure and grab them . Acquire a pistol and ammo .
“I visited Phuket, Thailand”
in the 2004 event , only certain sections of Phuket were affected , the open ocean sides . Inland sides hardly at all , a few meters up the hills not at all . Lower islands with built up low lying saddles got swept through and devastated the worst . The locals are still seeing the ghosts .
Maybe the PI will be like that in places now too .
“I was in a 7.5 in Mexico City (1957?)”
Our big quake in October was a 7.2 on October 15.
Even though I see Bohol from my beach, the damage here was not so severe, but broken and leaking water lines still plague the town, and the ancient Catholic church had damage that closed it. Nerves, however, were shaken. My porter and I were shoving a new case of beer under the fridge at the time. We both made a dash to the door and up to the beach road. Aftershocks continue almost daily.
See those that say Bohol or Tagbilaran. I can see the glow from the lights of that city from my beach. There was a 3.1 just 4 hours ago.
“in the 2004 event , only certain sections of Phuket were affected , the open ocean sides . Inland sides hardly at all”
Yes, Phuket is a big area...barely an island, as a bridge connects it to the mainland on the north.
The heavy damage was at the seaside resorts along the Indian ocean coast lines.
Tsunamis have little impact on anything other then seashore towns/cities.
in some cases there IS quite a bit of island ‘wrap-around’
I believe it takes deep offshore waters to do that and extensive wrapping tsunamis tend not to occur in the shallow SEA seas so much . Just a theory .
Every tsunami is different .
” The heavy damage was at the seaside resorts along the Indian ocean coast lines.”
and along the Phang Nga province north of Phuket , where the waves went straight in . But not too far . Many were able to escape uphill . However ,if you couldn’t get up that hill you were toast
“in some cases there IS quite a bit of island wrap-around”
Yes, the tsunami special that I saw on Natl.Geo ?
emphasized how they can wrap around an island.
That would NOT apply to most all of Cebu island.
How much was Cebu affected by the typhoon ?
Actually, Phuket has a considerable amount of high ground.
The resort that I was in was hundreds of feet above the shoreline
“How much was Cebu affected by the typhoon ?”
Not bad at all where I live, 2 hours south of Cebu city.
As a precaution, we spent two nights in a hotel over on the main highway, but my house, 100 ft from the shore, had no damage. Power in our town was out for about 8 hours.
There was a bit more damage in Cebu City. but I have not been up there since the typhoon.
Great find! Thanks!
BTW, I skimmed the article twice but did not find the elevation above sea level of the opening of the cave. Would you ping me as to that fact? Thanks.
Hope not ... would be devastating. Same with a southwest cauldron explosion ... doubly devastating. Prayer for neither.
If the New Madrid were to elicit even a 6+ on the Richter Scale it wouldn't be the damage of the earthquake that would be devastating, it would be the actions of the indigenous population of the major city that would make New Orleans/Katrina look like a minor event.
The New Madrid quakes were not only very large, but their effects were felt over very long distancesas far away as the east coast. Don’t know about Memphis, but St. Louis is a city built of brick. Brick buildings don’t fare well in earthquakes. The death toll in STL alone would be huge.
As I travel to points east of the river at Memphis, have looked into alternative routing based on survival of bridge structure post a New Madrid shake. The I-40 span was strengthened and may survive, but the approaches will need rebuild to use. The crossing at Natchez may be a sufficient distance south to avoid liquefaction issues. Suspect the new Hannibal, Mo. bridge for I-72 extension is driven to bedrock and will survive.
Rail, grid crossings, pipeline, barge traffic in addition to trucking will be curtailed. Highways in the river basin sediment plain will fail due to subsidence. Earthen levy failure will be dessert.
“Earthen levy failure will be dessert.”
Horrid to imagine a New Madrid 10.0 happening during spring melt water floods.
My wife is from Oroquieta City, on Mindanao. I’m sure that’s not far from you. Before we got married she and her family lived on a beach. Thankfully they never got a tsunami, but she remembered one that hit a nearby city (Dipolog?) in 1977 and killed 3,000 people.
That’s fascinating how they can look back through the strata.
Yes, Dipalog is exposed to a large expanse of open sea/ocean.
While I am on a beach, I am surrounded by other islands.
As with the Typhoon that hit Leyte, it does not take much to kill many people in the Philippines. So many live in shabby bamboo huts. Where I live, everything is concrete.
I am more concerned with earthquakes. I know, and can prepare for a typhoon, but not a quake.
I forgot...Go to this link. Study the photo before reading the text...I see a house with some damaged fence in front.
It is not what I thought, haha.
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