Lima

[QUOTE=Lima Busy]So if you want to come down later this month (I will give you a deal)ja ja.[/QUOTE]

Well I will be in Ecuador in a couple of weeks, but don't think that Lima is in the cards. It's great that your building stood up to the quakes. What do you figure the intensity of the quake was in Miraflores? 6.0? I know that it was 8.0 at the origin, but not sure what it was in Lima.

[QUOTE=Gonzo]don't go diving underneath furniture, but lay beside a strong piece of furniture , so when the ceiling comes down it will create a triangular space between the floor and the top of the furniture. [/QUOTE]Luckily many buildings in Lima have an "S" area marked out which is supposed to be safer than other parts of the building. I wonder what it's worth. There is at least some disaster-consciousness in Lima. No such thing in Jakarta for instance. The same quake in Jakarta would kill thousands. Note that being in a district like Miraflores where buildings are of higher quality is not necessarily safer. The nature of the substrate matters a lot. If it's unconsolidated (sand, conglomerate, alluvium) it's bad and judging by the cliff exposures at Marcomar, soft rock is just what we have in Miraflores. Hard crystalline substrate (granite, quartzite, massive limestone etc.) increases the odds that buildings will stand. I wouldn't like to be in Miraflores, not even in the 5-star buildings, when an earthquake this magnitude strikes right under it.

[QUOTE=Polvo]...There may be small aftershocks - but the seal has been popped and you will be OK - more biggies highly unlikely.....Polvo[/QUOTE]

Excuse me while I eat my words. A "small" aftershock of 5.9 has just been reported 105 miles south south-east of Lima by USGS. (Location 13.512°S, 76.467°W, Depth 31.9 km (19.8 miles) .)


Humbled.

Polvo

[QUOTE=Jaimito Cartero]Well I will be in Ecuador in a couple of weeks, but don't think that Lima is in the cards. It's great that your building stood up to the quakes. What do you figure the intensity of the quake was in Miraflores? 6.0? I know that it was 8.0 at the origin, but not sure what it was in Lima.[/QUOTE]The Richter number is the energy release at the point of origin. There is no such thing as a Richter number 100 miles away.

Does anyone know how long the threat of aftershocks or other quakes last ?

Maybe 1 month ?


I know they can happen anytime but in relation to this one that just happened.

[QUOTE=Artisttyp]Does anyone know how long the threat of aftershocks or other quakes last [/QUOTE]Actually aftershocks are great while having sex because it gives added vibration during penetration. Obviously in a motel/hostal you would be careful to lie down and have the woman on top in case that ceiling mirror sheds pieces. The aftershocks + the girl being impaled by falling shards while she's riding you: the ultimate kick!

Ok Im sold. It wont be for a few weeks anyway.

[QUOTE=Stocks Man]The Richter number is the energy release at the point of origin. There is no such thing as a Richter number 100 miles away.[/QUOTE]

Yes, but there must be some correlation to what the intensity would be, say 50 miles away, or an earthquake sensor in Lima would register, say a 5.8, even though the center of the quake was 100 miles away.

Basically what I'm trying to figure out is what type of shaking Lima actually got.

[QUOTE=Jaimito Cartero]Yes, but there must be some correlation to what the intensity would be, say 50 miles away, or an earthquake sensor in Lima would register, say a 5.8, even though the center of the quake was 100 miles away.

Basically what I'm trying to figure out is what type of shaking Lima actually got.[/QUOTE]No quake expert here, but this is what i heard and felt. It started with a loud,very loud groaning sound (normally a loud bang).I live on the beach on the first floor and ran outside(next door is a new 20 story tower under final construction)It was my incorrect belief that this noise was the building in the process of collapsing ( it did not). The main barrage was 2 minutes long and the sidewalk was rolling, light post's swaying and then it stopped. The first wave we held on to each other to avoid falling down. The subsequent after shocks (for 5 min or so was much less intense (no noise) and was akin to being on a ship.

As this is reported to be SA biggest earthquake I can tell you it was unlike all the others I have felt.

I answered you earlier, but did not realize Rosita was still logged in (shades of Maria Louisa)so you may think she answered you. I ran into Mary (remember her?) recently and she was looking real good.

Lima Crowd & Friends. It turns out Ian was on a bus near Ica when the earthquake happened. He was stranded and claims had a near death experience but managed to get to Arequipa about a hour ago. He will be back in Lima and staying at the Penthouse in a few days (flights are a ***** with all the tourists trying to get back to Lima).
regards,
LB

[QUOTE=Jaimito Cartero]Basically what I'm trying to figure out is what type of shaking Lima actually got.[/QUOTE]Geologists are able to estimate the subjective nature of a quake as a function of distance and what the ground is made of. Here is a 'shakemap' of the quake.

[url]http://preview.*******.com/ytyu8h[/url]

Is there any concern in lima about the 600+ who escaped from the prison in chincha?

I doubt they have an immediate way of getting to lima but 600+ is a huge prison break.

* A wall at the chincha prison gave way during the quake and alot of people escaped. The authorities have only captured 29 when last I heard.

[QUOTE=Jaimito Cartero]Basically what I'm trying to figure out is what type of shaking Lima actually got.[/QUOTE][url]http://preview.*******.com/ytyu8h[/url]

[QUOTE=Jaimito Cartero]Yes, but there must be some correlation to what the intensity would be, say 50 miles away, or an earthquake sensor in Lima would register, say a 5.8, even though the center of the quake was 100 miles away.

Basically what I'm trying to figure out is what type of shaking Lima actually got.[/QUOTE]
What the [url=http://earthquake.usgs.gov/eqcenter/shakemap/global/shake/2007gbcv/]USGS "Shakemap"[/url] shows is the local intensity according to the "Modified Mercalli Intensity Scale", which describes the subjective effects of an earthquake in a particular area. It's arguably a more useful scale for people unconcerned with geology, as it tells you roughly what the earthquake actually did to people and structures.

In contrast, the logarithmic magnitude scales (such as Richter's local magnitude scale) are related to the absolute amount of energy released by a seismic event (like Stocks Man mentioned earlier), and says nothing about how much of that energy actually makes it to the surface via pressure and shear waves without dissipating in the earth between the hypocenter (actual location of the event) and epicenter (surface location directly above the event).

That is to say it's very difficult to assign an absolute conversion to some "apparent Richter magnitude" felt in a certain location, as an earthquake measuring 6.0 at a hypocenter depth of 20 km will feel very different at the epicenter than will an earthquake measuring 6.0 at a hypocenter depth of 50 km.

I know I'm kinda rambling here, as I'm not exactly an expert on the subject (I've only gotten as far as sophomore-level college Physics), but that's about the best job I can do in explaining why it's hard to say that Lima experienced an "apparent X.y-magnitude" quake.

The data, then, courtesy of the [url=http://earthquake.usgs.gov/eqcenter/shakemap/global/shake/2007gbcv/stationlist.html]USGS Seismic Station Data List[/url]:

Chincha Alta (Chincha Province, Ica Region) and
Imperial (Cañete Province, Lima Region) are both 40.0 km from the epicenter:
--- [url=http://en.wikipedia.org/wiki/Mercalli_intensity_scale]Modified Mercalli Intensity[/url]: VIII (Considerable damage in all but specially designed structures)
--- Velocity (est. cm/s): 48.5153
--- Acceleration (est. % of g): 50.3872

Lima (Lima Province, Lima Region) 105.6 km from the epicenter:
--- [url=http://en.wikipedia.org/wiki/Mercalli_intensity_scale]Modified Mercalli Intensity[/url]: VI (Slight damage to structures, but easily noticeable shaking)
--- Velocity (est. cm/s): 10.5452
--- Acceleration (est. % of g): 11.8551

So there you have it. The magnitude of the shaking was clearly nowhere near as great in Lima as was the shaking closer to the epicenter. However, it was strong enough to scare a lot of people even in Lima. I hope you found this useful.

And another note: It's more and more rare for earthquake magnitude to be measured with the Richter scale. Now, the "Moment Magnitude Scale" is used, which is very similar, but yields values different by a decimal point or two.

We are coming to Lima on August 19th same as planned. Thank you very much for the information, I hope to remember this trip for a very long time. Hopefully the reasons i remember this trip will all be pleasant.


Regards,

John.