| Printable Version of Topic
Click here to view this topic in its original format |
| Celtic Radio Community > General Discussion > Earthquakes |
| Posted by: stevenpd 06-Aug-2009, 02:09 PM | ||
This is in response to Donajhi's questions about earthquakes just to keep "What are you doing now" thread simple.
Slim to none that a fault would open up in that way. Most likely all you would see would be a crack in the ground only a foot or so deep. At this is at the fault itself. Most likely you would see nothing at all. If you want more of an explanation read on. I currently reside in southern California and have been through several quakes of different magnitudes so I think I can answer his question with a certain level of certainty. My first major earthquake that I can recall was the Sylmar quake in 1971. Some background first. The surface of the earth is covered with these large pieces of surface that scientists call tectonic plates. The theory is that all of the land masses were, at one time, together and then began to shift and divide up into the continents. When these plates shift and bump into one another we get a quake. Earthquakes usually occur at these boundaries and can be several miles down. The size of the quake is dependent upon how much movement there is between the plates. Another factor in an earthquake is the soil type itself. Solid rock or just sand. Each reacts in there own way. Rock has a tendency to move monolithically whereas sand does a funny thing called liquefaction. Now the depth of the quake will determine the amount of movement on the surface. There can be little or no movement or substantial movement of several feet, vertically or horizontally. Most of the pictures you see of earthquake damage occurs with a horizontal slip close to the surface with differential settlement occurring depending on soil conditions. It can be disconcerting if you never experienced one before. |
| Posted by: lschillinger 07-Aug-2009, 02:22 AM |
| Oddly enough.....I've been through TWO earthquakes both in OHIO! |
| Posted by: stevenpd 07-Aug-2009, 09:51 AM |
| We had visitors from Scotland that just happened to arrive the day before our Northridge earthquake(January 17, 1994 at 4:31am). One of the reasons that they did not come sooner was because of their fear of an earthquake. Boy, did they get a rude wake-up call! If anyone is interested, check out http://earthquake.usgs.gov/ site for more info. They monitor earthquakes from around the world. Not only can you see where but also how strong. |
| Posted by: Camac 07-Aug-2009, 12:38 PM |
| stevenpd; I live at the Northwest corner of Lake Ontario not far from the Niagara escarpment and we get minor earthquakes and tremours all the time. About 8 years ago we had one that actually shook the apartment building causing minor panic amongst some of the tenants. There is a fault line about 1/2 kilometre off shore that runs almost the entire length of Lake Ontario and that was only discover about 30 years ago by none other than Jacques Cousteau on a underwater survey looking for ship wrecks. Camac. |
| Posted by: Patch 07-Aug-2009, 05:38 PM |
| We had two where I live, both minor, and I slept through one of them. There is a major fault about 20 miles from me. It is the one that caused the change in the course of the Mississippi river in the 1800's. There is an area along the fault that is a honey comb of sand pockets caused by the big quake back then. Farmers here sometimes have to have equipment extricated from the sand if it is too wet. Slàinte, Patch |
| Posted by: stevenpd 28-Aug-2009, 07:45 PM |
| From USGS: Earthquake Details Magnitude 6.2 Date-Time * Friday, August 28, 2009 at 01:52:06 UTC * Friday, August 28, 2009 at 09:52:06 AM at epicenter * Time of Earthquake in other Time Zones: Thursday, August 27, 2009 at 11:22:06 PM (NDT) - Newfoundland Daylight (St. John's) Thursday, August 27, 2009 at 10:52:06 PM (ADT) - Atlantic Daylight (Halifax) Thursday, August 27, 2009 at 09:52:06 PM (AST) - Atlantic Standard (San Juan) Thursday, August 27, 2009 at 09:52:06 PM (EDT) - Eastern Daylight (New York, Toronto) Thursday, August 27, 2009 at 08:52:06 PM (EST) - Eastern Standard (Jamaica) Thursday, August 27, 2009 at 08:52:06 PM (CDT) - Central Daylight (Winnipeg, Chicago, Mexico City) Thursday, August 27, 2009 at 07:52:06 PM (CST) - Central Standard (Regina, Costa Rica) Thursday, August 27, 2009 at 07:52:06 PM (MDT) - Mountain Daylight (Calgary, Denver Mazatlan) Thursday, August 27, 2009 at 06:52:06 PM (MST) - Mountain Standard (Phoenix) Thursday, August 27, 2009 at 06:52:06 PM (PDT) - Pacific Daylight (Vancouver, Los Angeles, Tijuana) Thursday, August 27, 2009 at 05:52:06 PM (AKDT) - Alaska Daylight (Anchorage) Thursday, August 27, 2009 at 04:52:06 PM (AHDT) - Aleutian Daylight (Adak) Thursday, August 27, 2009 at 03:52:06 PM (HST) - Hawaii Standard (Honolulu) Location 37.721°N, 95.684°E Depth 10 km (6.2 miles) set by location program Region NORTHERN QINGHAI, CHINA Distances 35 km (20 miles) ESE of Da Qaidam, Qinghai, China 165 km (100 miles) NNE of Golmud, Qinghai, China 1815 km (1120 miles) W of BEIJING, Beijing, China Location Uncertainty horizontal +/- 8.1 km (5.0 miles); depth fixed by location program Parameters NST= 79, Nph= 79, Dmin=>999 km, Rmss=0.92 sec, Gp= 94°, M-type=teleseismic moment magnitude (Mw), Version=7 Source * USGS NEIC (WDCS-D) Event ID us2009kwaf * This event has been reviewed by a seismologist. |
| Posted by: stevenpd 03-Sep-2009, 11:31 PM | ||
| When California falls into the ocean I will be surfing to Colorado. I'll be back when settled. From USGS:
|
| Posted by: Patch 04-Sep-2009, 07:30 AM |
| I have some news to catch up on. I have been too busy of late. Slàinte, Patch |