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Thread: Earthquakes: what happens when you are on a boat in a lake

  1. #1 Earthquakes: what happens when you are on a boat in a lake 
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    Hello everyone. I hope you can help me with the following question.

    What happens when you are on a boat on a lake and an earthquake happens? Would it be safer than being on land? Should you use an anchor or not? Will you even notice the shocks?


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    It would depend on how large the quake is and how near you are to the epicenter.


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    I'm especially interested in the differences between being on land and being on a lake.

    For example: around 6 on the Richter magnitude scale. On land you will certainly feel this, and buildings might collapse, but I suppose on boats in the middle of a lake you might just have to deal with some waves. Am I correct to assume this?
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    Quote Originally Posted by Mononoke View Post
    I'm especially interested in the differences between being on land and being on a lake.

    For example: around 6 on the Richter magnitude scale. On land you will certainly feel this, and buildings might collapse, but I suppose on boats in the middle of a lake you might just have to deal with some waves. Am I correct to assume this?
    Well, waves are what you are dealing with, whether you are on land or water. The difference is the medium. The effect on water will probably depend on the position of the water, relative to the epicentre. For example if you have a fault that shears, say North/South, you will get an initial pulse of compression going North on the West side and South on the East side, which will be followed by a phase of rarefaction and so on. I understand (I'm not expert on this) that it will give you a quadrupole radiation of waves, with 2 nodal directions where nothing happens, which if I recall correctly will the N-S and E-W directions. If your water were to be in one of these nodal directions, relative to the epicentre then I suppose you would experience little, whereas if you were in a NW or SE or a NE or SW direction you would experience strong "sloshing" of the water in the lake.

    But here I'd have to invite a seismologist to comment - I may have got it all wrong.
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    Thank you all for helping me with this. I've read your explanation exchemist, and also the webpage jrmonroe posted. It is quite complicated (I don't have a lot of science knowledge). I even made a recap in my own language so to understand it better :P. I hope you'll all forgive me for asking things that might be very basic for you all.

    - P waves will travel through water just as much as trough stone. With the help of the article I was able to look a bit further on the internet and find this on wiki: 'Typical speeds are 330 m/s in air, 1450 m/s in water and about 5000 m/s in granite.' But if it behaves like a soundwave, the speed does not have much effect on the amplitude or frequency: so am I correct that the kind of 'force' (don't know how to describe it otherwise) it releases on the environment is the same in water as on land.
    - S waves will not travel in liquids and so have little/none effects on the lake. (Although I suppose the wave going underneath the might make the soil move there and indirectly make the water in the lake move too).
    - From the surface waves a 'Love wave' does not travel trough the water, but it will make the water sort of vibrate.
    The 'Rayleigh wave' will have (the same as on land?) effect on a lake.
    - Where the wave comes from and how far from the epicentre it is, makes a difference to the effect it will have.

    My conclusion so far is.. well, that I really can't wrap my head around it at all :P. I feel quite stupid now .
    But anyway, is it correct to say that as some waves (S, Love) do not travel through water, you might experience less effects of the earthquakes waves on a lake (and how big the difference is, depends on where you are in relation to the epicentre)?
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    They produce transverse waves which causes transverse movement of the earth crust and the major effects which you know are building collapses,etc

    And since all waves are dependent on the medium of propagation(with electromagnetic waves been able to travel through a vacuum),I think the effect would be felt much when you are on land due to the closure of the particles that transfer the energy from one place to another. Unlike the water that are farther spaced#

    Above is what I can conjure although am no expert here#
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    Quote Originally Posted by Mononoke View Post
    Hello everyone. I hope you can help me with the following question.

    What happens when you are on a boat on a lake and an earthquake happens? Would it be safer than being on land? Should you use an anchor or not? Will you even notice the shocks?
    During the October 16th 2006 HUGE earthquake in Hawai'i.....6.8 shook for almost a minute....followed ten minutes later by a 6.6 aftershock...and many others, I had friends IN the water surfing, a person I met who was on a dock, and I was at home.

    The experience of those in the water and it was centered pretty much off where they were surfing, was that the land kept coming towards them and then away from them and that the marine life was jumping out of the water like crazy.

    The person on the dock was holding on to it as not to fall in the water, and watched as after the earthquake stopped, about 100 yards out he saw the ocean literally part out and the bottom exposed and fish flying all over the place....(I did ask him if his name was Moses).

    On land....well it woke me up....first thinking (being from Northern Cali, we get them all the time) "Oh, it's an earthquake." However, this was UNLIKE any I have ever experienced. It was extremely violent. I was catching lamps, painting all flew off the walls, wine cabinet had wine and glassware flying out as did all my kitchen cabinets.....moved my 1/2 p/u truck 6 inches from my car....and almost tore my water heater off the wall.

    I certainly would NOT use an anchor.....and just ride it out.

    One of the quakes I experienced in Northern Cali, I was driving. The road was doing waves....literally...
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    Fascinating entry! Thank you! jocular
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    Quote Originally Posted by babe View Post
    Quote Originally Posted by Mononoke View Post
    Hello everyone. I hope you can help me with the following question.

    What happens when you are on a boat on a lake and an earthquake happens? Would it be safer than being on land? Should you use an anchor or not? Will you even notice the shocks?
    During the October 16th 2006 HUGE earthquake in Hawai'i.....6.8 shook for almost a minute....followed ten minutes later by a 6.6 aftershock...and many others, I had friends IN the water surfing, a person I met who was on a dock, and I was at home.

    The experience of those in the water and it was centered pretty much off where they were surfing, was that the land kept coming towards them and then away from them and that the marine life was jumping out of the water like crazy.

    The person on the dock was holding on to it as not to fall in the water, and watched as after the earthquake stopped, about 100 yards out he saw the ocean literally part out and the bottom exposed and fish flying all over the place....(I did ask him if his name was Moses).

    On land....well it woke me up....first thinking (being from Northern Cali, we get them all the time) "Oh, it's an earthquake." However, this was UNLIKE any I have ever experienced. It was extremely violent. I was catching lamps, painting all flew off the walls, wine cabinet had wine and glassware flying out as did all my kitchen cabinets.....moved my 1/2 p/u truck 6 inches from my car....and almost tore my water heater off the wall.

    I certainly would NOT use an anchor.....and just ride it out.

    One of the quakes I experienced in Northern Cali, I was driving. The road was doing waves....literally...
    Your post illustrates vividly the reasons why I declined to accept a job offer in California, years ago. joc
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    During a recent 6+ earthquake near where I live large mats of floating vegetation surfaced at a small lake and took several days to settle.
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    Quote Originally Posted by jocular View Post
    Quote Originally Posted by babe View Post
    Quote Originally Posted by Mononoke View Post
    Hello everyone. I hope you can help me with the following question.

    What happens when you are on a boat on a lake and an earthquake happens? Would it be safer than being on land? Should you use an anchor or not? Will you even notice the shocks?
    During the October 16th 2006 HUGE earthquake in Hawai'i.....6.8 shook for almost a minute....followed ten minutes later by a 6.6 aftershock...and many others, I had friends IN the water surfing, a person I met who was on a dock, and I was at home.

    The experience of those in the water and it was centered pretty much off where they were surfing, was that the land kept coming towards them and then away from them and that the marine life was jumping out of the water like crazy.

    The person on the dock was holding on to it as not to fall in the water, and watched as after the earthquake stopped, about 100 yards out he saw the ocean literally part out and the bottom exposed and fish flying all over the place....(I did ask him if his name was Moses).

    On land....well it woke me up....first thinking (being from Northern Cali, we get them all the time) "Oh, it's an earthquake." However, this was UNLIKE any I have ever experienced. It was extremely violent. I was catching lamps, painting all flew off the walls, wine cabinet had wine and glassware flying out as did all my kitchen cabinets.....moved my 1/2 p/u truck 6 inches from my car....and almost tore my water heater off the wall.

    I certainly would NOT use an anchor.....and just ride it out.

    One of the quakes I experienced in Northern Cali, I was driving. The road was doing waves....literally...
    Your post illustrates vividly the reasons why I declined to accept a job offer in California, years ago. joc
    Did you foresee the earthquake or what?
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    Quote Originally Posted by jocular View Post
    Quote Originally Posted by babe View Post
    Quote Originally Posted by mononoke View Post
    hello everyone. I hope you can help me with the following question.

    What happens when you are on a boat on a lake and an earthquake happens? Would it be safer than being on land? Should you use an anchor or not? Will you even notice the shocks?
    during the october 16th 2006 huge earthquake in hawai'i.....6.8 shook for almost a minute....followed ten minutes later by a 6.6 aftershock...and many others, i had friends in the water surfing, a person i met who was on a dock, and i was at home.

    The first one was in hawai'i.

    The one driving was in cali.

    Chicken! *ducking*

    the experience of those in the water and it was centered pretty much off where they were surfing, was that the land kept coming towards them and then away from them and that the marine life was jumping out of the water like crazy.

    The person on the dock was holding on to it as not to fall in the water, and watched as after the earthquake stopped, about 100 yards out he saw the ocean literally part out and the bottom exposed and fish flying all over the place....(i did ask him if his name was moses).

    On land....well it woke me up....first thinking (being from northern cali, we get them all the time) "oh, it's an earthquake." however, this was unlike any i have ever experienced. It was extremely violent. I was catching lamps, painting all flew off the walls, wine cabinet had wine and glassware flying out as did all my kitchen cabinets.....moved my 1/2 p/u truck 6 inches from my car....and almost tore my water heater off the wall.

    I certainly would not use an anchor.....and just ride it out.

    One of the quakes i experienced in northern cali, i was driving. The road was doing waves....literally...
    your post illustrates vividly the reasons why i declined to accept a job offer in california, years ago. Joc
    this
    Last edited by babe; September 25th, 2013 at 01:21 AM. Reason: posted one word..not the entire reply though shows the entire reply when I try to edit!! GRRRRR
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    Quote Originally Posted by Lynx_Fox View Post
    During a recent 6+ earthquake near where I live large mats of floating vegetation surfaced at a small lake and took several days to settle.
    Not surprising!
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    Quote Originally Posted by merumario View Post
    Quote Originally Posted by jocular View Post
    Quote Originally Posted by babe View Post
    Quote Originally Posted by Mononoke View Post
    Hello everyone. I hope you can help me with the following question.

    What happens when you are on a boat on a lake and an earthquake happens? Would it be safer than being on land? Should you use an anchor or not? Will you even notice the shocks?
    During the October 16th 2006 HUGE earthquake in Hawai'i.....6.8 shook for almost a minute....followed ten minutes later by a 6.6 aftershock...and many others, I had friends IN the water surfing, a person I met who was on a dock, and I was at home.

    The experience of those in the water and it was centered pretty much off where they were surfing, was that the land kept coming towards them and then away from them and that the marine life was jumping out of the water like crazy.

    The person on the dock was holding on to it as not to fall in the water, and watched as after the earthquake stopped, about 100 yards out he saw the ocean literally part out and the bottom exposed and fish flying all over the place....(I did ask him if his name was Moses).

    On land....well it woke me up....first thinking (being from Northern Cali, we get them all the time) "Oh, it's an earthquake." However, this was UNLIKE any I have ever experienced. It was extremely violent. I was catching lamps, painting all flew off the walls, wine cabinet had wine and glassware flying out as did all my kitchen cabinets.....moved my 1/2 p/u truck 6 inches from my car....and almost tore my water heater off the wall.

    I certainly would NOT use an anchor.....and just ride it out.

    One of the quakes I experienced in Northern Cali, I was driving. The road was doing waves....literally...
    Your post illustrates vividly the reasons why I declined to accept a job offer in California, years ago. joc
    Did you foresee the earthquake or what?
    Heaven's no
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    Quote Originally Posted by jocular View Post
    Quote Originally Posted by babe View Post
    Quote Originally Posted by Mononoke View Post
    Hello everyone. I hope you can help me with the following question.

    What happens when you are on a boat on a lake and an earthquake happens? Would it be safer than being on land? Should you use an anchor or not? Will you even notice the shocks?
    During the October 16th 2006 HUGE earthquake in Hawai'i.....6.8 shook for almost a minute....followed ten minutes later by a 6.6 aftershock...and many others, I had friends IN the water surfing, a person I met who was on a dock, and I was at home.

    The experience of those in the water and it was centered pretty much off where they were surfing, was that the land kept coming towards them and then away from them and that the marine life was jumping out of the water like crazy.

    The person on the dock was holding on to it as not to fall in the water, and watched as after the earthquake stopped, about 100 yards out he saw the ocean literally part out and the bottom exposed and fish flying all over the place....(I did ask him if his name was Moses).

    On land....well it woke me up....first thinking (being from Northern Cali, we get them all the time) "Oh, it's an earthquake." However, this was UNLIKE any I have ever experienced. It was extremely violent. I was catching lamps, painting all flew off the walls, wine cabinet had wine and glassware flying out as did all my kitchen cabinets.....moved my 1/2 p/u truck 6 inches from my car....and almost tore my water heater off the wall.

    I certainly would NOT use an anchor.....and just ride it out.

    One of the quakes I experienced in Northern Cali, I was driving. The road was doing waves....literally...
    Your post illustrates vividly the reasons why I declined to accept a job offer in California, years ago. joc
    First earthquake I referred to was in Hawai'i....the second was in Cali.
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    Regardless of the magnitude. ( almost ) The energy spent and how near to you that ground action motion and movement was/is
    Is what you will feel.. or notice.. Near to you motions of movement will flatten your house in a instant,, while some distance a wave like action of much lesser violence is experienced. If you are on water ( your lake ) then you might not even notice a strong earth tremor.. but near the shore it could get exciting.. or ugly.. Looking across a near to me lake while a 6.2 rolled in.. the lake tipped left and right. Setting up a two metre wave.. very little damage and just a wobble on shore looked like the wave was coming ashore.. It didn't. It vanished as if it was never there.
    Energy imparted is more important than the 'Richter scale' number.. and how deep it is.. what type of shear action, vertical or flat.
    I for many years have worked with subsurface typography sounding and we use waves to 'Map' the rock structures deep off the Continental shelf's.. Nothing messes up a reading more than a earthquake..
    I live in New Zealand. Earthquakes are part of this place.. never getting complacent and always aware of the danger.. Fortunatly even here these things are not life controlling events..
    No do not drop anchor.. and sleep right through it..
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    Quote Originally Posted by astromark View Post
    Regardless of the magnitude. ( almost ) The energy spent and how near to you that ground action motion and movement was/is
    Is what you will feel.. or notice.. Near to you motions of movement will flatten your house in a instant,, while some distance a wave like action of much lesser violence is experienced. If you are on water ( your lake ) then you might not even notice a strong earth tremor.. but near the shore it could get exciting.. or ugly.. Looking across a near to me lake while a 6.2 rolled in.. the lake tipped left and right. Setting up a two metre wave.. very little damage and just a wobble on shore looked like the wave was coming ashore.. It didn't. It vanished as if it was never there.
    Energy imparted is more important than the 'Richter scale' number.. and how deep it is.. what type of shear action, vertical or flat.
    I for many years have worked with subsurface typography sounding and we use waves to 'Map' the rock structures deep off the Continental shelf's.. Nothing messes up a reading more than a earthquake..
    I live in New Zealand. Earthquakes are part of this place.. never getting complacent and always aware of the danger.. Fortunatly even here these things are not life controlling events..
    No do not drop anchor.. and sleep right through it..
    We agree!! I have been through earthquakes all my life. They have been part of my life.

    ALways also keep some food and water for a few days in your house, just in case of a BIG ONE!
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    Some study of the GEO-NET sites will quickly inform the uninformed. Here in NZ it's GEO NET and for the USA It's the USGS
    A visit to there site will widen your knowledge 'Mononoke' and 'Jocular'.. ie; jocular mentioned not working in California..
    I would want to advise that very little danger is found there.. I would not want to live in the volcanic caldera of Yellowstone Park..
    Like NZ's Toupo region.. nasty and explosive events of the past are good warnings for us.. and on a Global view standpoint..
    Very few places on planet Earth are truly safe.. Just a mater of controlling the balance of risk and history.. In the recorded history of the human race.. We have been 'Lucky'. comparatively.
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    Quote Originally Posted by astromark View Post
    Some study of the GEO-NET sites will quickly inform the uninformed. Here in NZ it's GEO NET and for the USA It's the USGS
    A visit to there site will widen your knowledge 'Mononoke' and 'Jocular'.. ie; jocular mentioned not working in California..
    I would want to advise that very little danger is found there.. I would not want to live in the volcanic caldera of Yellowstone Park..
    Like NZ's Toupo region.. nasty and explosive events of the past are good warnings for us.. and on a Global view standpoint..
    Very few places on planet Earth are truly safe.. Just a mater of controlling the balance of risk and history.. In the recorded history of the human race.. We have been 'Lucky'. comparatively.
    I also live with 4 active volcano's on the Big Island of Hawai'i. Our first earthquake there in 23 years was in 2006 and was horrific
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    This is just like a bowl of water. When you move the bow, the water may spill out. Of course, this is a big bowl. But I think the basic processes are the same.
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    Quote Originally Posted by heaventian View Post
    This is just like a bowl of water. When you move the bow, the water may spill out. Of course, this is a big bowl. But I think the basic processes are the same.
    Interesting interpretation!
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    Quote Originally Posted by Mononoke View Post
    Hello everyone. I hope you can help me with the following question.

    What happens when you are on a boat on a lake and an earthquake happens? Would it be safer than being on land? Should you use an anchor or not? Will you even notice the shocks?
    You're asking about tsunamis confined to small bodies of water. To a boater away from shore you might detect a gentle bump from the actual quake. These are very fast, very low waves. What the waves do as they're constricted by a narrowing bay or shallows is more dramatic, but, like ordinary waves it depends on wave direction and how the land sculpts them. The only hazard in deep water is where waves are rebounding from surrounding shorelines to converge where you are.

    I doubt an anchor would be a problem, as we use anchors in rough seas anyway; a springy nylon line at least 5x water depth is typical.
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    When we had the tsunami in 2011, (2011 Tōhoku earthquake) http://en.wikipedia.org/wiki/2011_Tō...ke_and_tsunami we had tsunami's here. They cause around 40 million in damage not to mention displacing some employees along the coast perementally.

    The rule of thumb, to everyone who had a watercraft moored, was to take it out at least a mile from the shore.......and keep it out there till the tsunami danger was over. No recommendation was given to drop an anchor.

    The sirens went on for HOURS and HOURS and HOURS....I finally went to bed at 4:00. I did not vacate, as even though I am very close to the ocean.....I sit high enough to not be affected, unless it was one from something like science fiction!

    However, having lived through the first major earthquake in Hawai'i in 23 years, and 3 tsunami's, (2011) is the one that was horrid for many, I think I would prefer not to live through any more natural disasters.

    Here is a video of a moron in Kailua....FILMING the Tsunami. The main town was closed for two weeks due to flooding.

    Video Surfaces Of Tsunami Wave Hitting Kona, Hawaii - YouTube
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    A point implicit in many of the foregoing posts is, I think, worth spelling out. Earthquakes are generally not dangerous unless you are in a structure that might collapse. Unlike the B movies the Earth rarely opens up in giant chasms to swallow the unsuspecting. Therefore, if you are in the open, the impact of a quake will be much the same on a boat as on the land.

    I'll just share one of my own quake experiences, which as a geologist I naturally enjoyed. This was a magnitude 7.0, some distance from Mexico City, where I was living at the time. It was morning and I had just got up when my shoes marched forward from under the bed - propelled by high frequency P-waves. A few moments later a panicky call from my wife led me to the kitchen, where the water in the sink was sluicing from side to side as the S-waves arrived and swayed our high rise building.

    I was closer to my geology degree in those days, so before the quake had finished I'd worked out an approximate distance to the epicentre based on the delay between the two waves and probable magnitude based upon the effects. Luck or a sickeningly adroit skill set led me to a pretty accurate answer.
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    one more of the tsunami.....what an IDIOT!

    Tsunami reaches Kona Hawaii - YouTube
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    Quote Originally Posted by John Galt View Post
    A point implicit in many of the foregoing posts is, I think, worth spelling out. Earthquakes are generally not dangerous unless you are in a structure that might collapse. Unlike the B movies the Earth rarely opens up in giant chasms to swallow the unsuspecting. Therefore, if you are in the open, the impact of a quake will be much the same on a boat as on the land.

    I'll just share one of my own quake experiences, which as a geologist I naturally enjoyed. This was a magnitude 7.0, some distance from Mexico City, where I was living at the time. It was morning and I had just got up when my shoes marched forward from under the bed - propelled by high frequency P-waves. A few moments later a panicky call from my wife led me to the kitchen, where the water in the sink was sluicing from side to side as the S-waves arrived and swayed our high rise building.

    I was closer to my geology degree in those days, so before the quake had finished I'd worked out an approximate distance to the epicentre based on the delay between the two waves and probable magnitude based upon the effects. Luck or a sickeningly adroit skill set led me to a pretty accurate answer.
    I have lived in earthquake country since I was a child. You can have them. (In Northern Cali we have them about once a week, though small in magnitude.)

    As to your comment about the earth opening up.

    When we had our earthquake in Hawai'i on October 16, 2006 it was the first one here in 23 years. It woke me up at 7:00.....I rolled over, "Oh just an earthquake." WRONG. It was the mother of any earthquake even the 7.2 in Humboldt way back when. Upper road was closed, lower road they closed when I drove the truck down to get in touch with my husband, so he wouldn't worry. No telephone, no power, and no cell reception While waiting to see if they would open lower road to Kawaihae, ran into a local who had been out fishing and was on his way back and had been on a ramp coming out of the water when the earthquake occurred. Well the water 100 yards off shore, did open to ocean bottom then close. I named him, "Moses." Said is was the strangest thing he had ever seen and he has lived here all his life.
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    Quote Originally Posted by babe View Post
    had been on a ramp coming out of the water when the earthquake occurred. Well the water 100 yards off shore, did open to ocean bottom then close.
    I can believe that, though I'm struggling to see how it happened. Boat-ramp suggests a rocky shoreline...? Was it in a bay?

    For British Columbia, we're kinda worried about what stunts the water will perform along our complicated coastline. Ordinary tidal action within the Strait causes white-water rapids and eddies, so presumably a local slosh-about tsunami will be magnitudes worse. I'm thinking that in general it'll be softened by the fact land is folded perpendicular to the direction of slip - waves will strike steep walls rather than focus up inlets.
    A pong by any other name is still a pong. -williampinn
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    Quote Originally Posted by Pong View Post
    Quote Originally Posted by babe View Post
    had been on a ramp coming out of the water when the earthquake occurred. Well the water 100 yards off shore, did open to ocean bottom then close.
    I can believe that, though I'm struggling to see how it happened. Boat-ramp suggests a rocky shoreline...? Was it in a bay?

    For British Columbia, we're kinda worried about what stunts the water will perform along our complicated coastline. Ordinary tidal action within the Strait causes white-water rapids and eddies, so presumably a local slosh-about tsunami will be magnitudes worse. I'm thinking that in general it'll be softened by the fact land is folded perpendicular to the direction of slip - waves will strike steep walls rather than focus up inlets.
    Yes, a small harbor


    He stated it was not directly ONSHORE but approximately 100 yards offshore.
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    I'm out of my depth but intuitively that does look more likely to produce a deep trough when kicked by titans.
    A pong by any other name is still a pong. -williampinn
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    Quote Originally Posted by Mononoke View Post
    Hello everyone. I hope you can help me with the following question.

    What happens when you are on a boat on a lake and an earthquake happens? Would it be safer than being on land? Should you use an anchor or not? Will you even notice the shocks?
    Safer on land would depend where you are in relation to the epicenter and what your surroundings are..
    If you're in a lake the earthquake could produce 1) large waves , 2) large swells 3) aggressive chop , or all 3. It all really depends on what position the lake is..
    If for example the lake experiences significant shaking as that on land which caused damage to buildings , serious injury , etc. You could experience a period of "shaky water" such as sporadic waves, and swell. Depending on the quake, size of the lake, and frequency of waves produced they could move in a number of different directions at once. You also have to take into account the possibility of falling debris such as land slides or loose rocky cliffs, which can generate a quick level of water displacement..

    Worst that could happen is your boat would capsize. In which case you'd be moved around in water and dunked by a variety of swells and waves until the movement of water lost momentum. The earthquake could also produce a tsunami in the lake as well. Really all depends on where the lake is, the size, where it sits, etc.
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    Quote Originally Posted by indyscience View Post
    Quote Originally Posted by Mononoke View Post
    Hello everyone. I hope you can help me with the following question.

    What happens when you are on a boat on a lake and an earthquake happens? Would it be safer than being on land? Should you use an anchor or not? Will you even notice the shocks?
    Safer on land would depend where you are in relation to the epicenter and what your surroundings are..
    If you're in a lake the earthquake could produce 1) large waves , 2) large swells 3) aggressive chop , or all 3. It all really depends on what position the lake is..
    If for example the lake experiences significant shaking as that on land which caused damage to buildings , serious injury , etc. You could experience a period of "shaky water" such as sporadic waves, and swell. Depending on the quake, size of the lake, and frequency of waves produced they could move in a number of different directions at once. You also have to take into account the possibility of falling debris such as land slides or loose rocky cliffs, which can generate a quick level of water displacement..

    Worst that could happen is your boat would capsize. In which case you'd be moved around in water and dunked by a variety of swells and waves until the movement of water lost momentum. The earthquake could also produce a tsunami in the lake as well. Really all depends on where the lake is, the size, where it sits, etc.
    *L* My girlfriend....a couple I met from Toronto, came to the island and wanted to see a tsunami. We had three in three years.....two which were tiny but amazing how they changed shoreline....one three years ago March.....which caused a lot of damage......but little media from the Mainland or anywhere else. That also major changed the shoreline....I told her to stop WISHING!
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    Anyway, the wave will be reflected by the bank.
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    Firstly I point to my own experiences as a guide to being a survivor.. and that some good luck as to your actual location is not something you can alter without good knowledge.. Being aware is almost as good as being ready..
    'Babe's experiences are as mine.. ( I dare not speak for; ) As we both live near active volcanic and frequent sismic actions, and with a science input some sense can be extracted by study. 'John Galt'., has added a note of science revue I find as true.. Not the cat running about like a idiot.. ( who could know what the cat felt..) but a heads up, the cat is spooked ! could save your life.
    ~ The arrival of the P wave. I describe as the high frequency vibration preceding the arrival of the S wave. The actual ground motion shock wave. Hugely dependent upon your location. A sandy loam or back fill of reclaimed Earth is not going to respond as a rock based substructure. The depth and your distance from the actual motion center is vital to what you will experience.. Violent sudden motion against a gentle rocking action. I do not like Earthquakes, but find them a very interesting study. Earths crust motion is ongoing. " the wave will be reflected by the bank".. is true, and Leeds me straight into 'the insurance companies' will screw you. ( The Bank pun was intended.)
    It's been two years since Christchurch was devastated and yet some homes as yet unlivable and are not yet assessed as repairable... That you pay your premiums and are for ever.. screwed. My miss trust has grown into direct hate,. Of the insurance industry. I do NOT like that I have grown to this view... but that it's true is real.
    We need to learn to build wiser and stronger homes and work places.. That we can gain knowledge of the science of 'ground motion' and 'bush fire' environments points me in this direction. I envisage a strong floating on a pond of loos rock shale and with a self re using water sprinkler system as not so hard to do.. Turning to science for a better future.
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    Quote Originally Posted by astromark View Post
    Firstly I point to my own experiences as a guide to being a survivor.. and that some good luck as to your actual location is not something you can alter without good knowledge.. Being aware is almost as good as being ready..
    'Babe's experiences are as mine.. ( I dare not speak for; ) As we both live near active volcanic and frequent sismic actions, and with a science input some sense can be extracted by study. 'John Galt'., has added a note of science revue I find as true.. Not the cat running about like a idiot.. ( who could know what the cat felt..) but a heads up, the cat is spooked ! could save your life.
    ~ The arrival of the P wave. I describe as the high frequency vibration preceding the arrival of the S wave. The actual ground motion shock wave. Hugely dependent upon your location. A sandy loam or back fill of reclaimed Earth is not going to respond as a rock based substructure. The depth and your distance from the actual motion center is vital to what you will experience.. Violent sudden motion against a gentle rocking action. I do not like Earthquakes, but find them a very interesting study. Earths crust motion is ongoing. " the wave will be reflected by the bank".. is true, and Leeds me straight into 'the insurance companies' will screw you. ( The Bank pun was intended.)
    It's been two years since Christchurch was devastated and yet some homes as yet unlivable and are not yet assessed as repairable... That you pay your premiums and are for ever.. screwed. My miss trust has grown into direct hate,. Of the insurance industry. I do NOT like that I have grown to this view... but that it's true is real.
    We need to learn to build wiser and stronger homes and work places.. That we can gain knowledge of the science of 'ground motion' and 'bush fire' environments points me in this direction. I envisage a strong floating on a pond of loos rock shale and with a self re using water sprinkler system as not so hard to do.. Turning to science for a better future.
    They are scary. We carry earthquake insurance and flood on the Mainland (major quake zone, big rain zone and that house is on a creek) and the deductible's are about 25,000. Here we are REQUIRED to carry Hurricane. I have no problem with insurance as I have seen them pay in Cali. I am unfamiliar with your insurance industry in New Zealand.

    I also find earthquakes interesting and frightening. I do not like watching things flying off walls, out of cabinets and the sound of breaking glass. I am no longer as quick to run and catch EVERY lamp in the house.

    THey are now telling us that we have 50% chance of having a humdinger in the next 10 years.
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    Growing up in California I experienced many earthquakes and one big one that destroyed a number of buildings, highways, and major bridges. 1994 Northridge earthquake - Wikipedia, the free encyclopedia
    Pretty scary stuff when they're above a 6.0. California is expected to have more with potentially more force which is darn scary if you consider the aging natural gas lines running through cities and the major farming industry which happens to run right on top of much of the San Andreas Fault in central Cali.

    Oh yeah, somewhat off-topic but Pennsylvania has been recording more seismic activity since fracking became popular.

    I wish I could contribute more to the OP's question but many people here have already said what I would have said.

    Very good posts!
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