Are Earthquakes Separated by 30 min & 2,500 miles Linked?

[dimensionless]

There was an earthquake measuring 6.2 a day or two ago in Indonesia. "Yesterday" there was another 6.2 earthquake recorded of the coast of Papua New Guinea. 30 minutes after that and 2,500 miles away in Tonga there was an earthquake measuring 6.7. Do these earthquakes have anything to do with one another? How about the volcano 25 miles north of the 6.2 Indonesian earthquake? It has been erupting for a few months and has shown a lot of activity in the last couple of weeks. Is the origin of this recent volcanic activity also responsible for the earthquakes?

Massive eruption feared following aftershocks
By Steve Bird
A SERIES of powerful aftershocks hit the Pacific basin’s volatile Ring of Fire yesterday giving rise to fears that the Mount Merapi, the smouldering volcano, could erupt.

The aftershocks follow the powerful earthquake that struck the island of Java early on Saturday morning.

More than 450 aftershocks have been recorded in the area, underlining the volatility of the region, an area at the mercy of faultlines and home to the world’s highest density of active and rumbling volcanoes.

The first big aftershock, with a magnitude of 6.2, was recorded shortly after 3am yesterday about 117 miles off the coast of New Britain, an island off Papua New Guinea’s northeast coast.

Around 30 minutes later a second aftershock hit the coast of Tonga, about 2,500 miles away. There were no reports of serious injuries in either incident.

http://www.timesonline.co.uk/article/0,,25689-2201276,00.html

 

[Ivan Seeking]

It would probably take some time to show if there is a direct connection. Having grown up watching seismic reports from Cal Tech on a regular basis, I do know that they used to dismiss the idea of quakes causing other quakes, but now seismologists discuss this idea regularly [on the science shows], and often refer to quake "swarms".

 

[jhe1984]

Ivan's got me beat on the qualifications side, but for my part I do know that in the last geophysics class I took, they talked about how certain seismic waves traveled (albeit dampened) across the Earth's inside.

Perhaps these disturbances could exarcebate already unstable seismic regions elsewhere?

 

[Ivan Seeking]

Funny enough, I took a 400 level geophysics class as part of my minor.

It could be a question of whether this was one quake or two, but the idea of one region of a fault stressing the next or an adjacent fault is a fairly recent discussion [last twenty years or so from what I've seen].

 

[Bystander]

http://neic.usgs.gov/neis/bulletin/neic_nabj_l.html

 

[Astronuc]

The earthquakes in Pupua New Guinea and Tonga are not directly related. However, the occur on the Intersection of the Australian Tectonic Plate with the Pacific Plate, and so they located in the same seismic zone. This is the western side of the Pacific Ring of Fire - so noted for the volanic activity along this region.

http://www.platetectonics.com/book/images/Tectonicplates.jpg

Papua New Guinea is located on intesection of the Australian and Pacific Plates, just south of where the Pacific and Philippine Plates intersect, and the Philippine Plate sits between the Asian and Pacific Plates. The Asian Plate jogs south under Pupua. West of Pupua, the intersection of the Australian and Asian plates concide the Sunda Trench, which borders Indonesia to the south. Tonga is located on the NW corner of the Australia plate where the Pacific Plate progresses from New Zealand, NNW to Tonga then turns westerly toward New Guinea.

The plate intersections from New Zealand to Tonga, and Tonga to Sumatra (to Aceh province) represents the most active seismic region in the world, besides the activity along the Aleutian Island and southern Alaska.

Shallow earthquakes in this area have the potential of causing significant tsunami events - hence the tsunami alert on May 3 with the Mag 7.9 earthquake near Tonga (20.088°S, 174.219°W), 160 km (100 miles) NE of Nuku'alofa, at 15:26:35 (UTC). Original estimates put the depth at 16.1 km (10.0 miles) or less, but subsequent investigations revealed that the earthquake was deeper, 55 km (34.2 miles), which presents a lesser threat for tsunami.

Swarms are generally considered local (i.e. within 100 miles or so) phenomenon. Tonga has had several swarms recently, and an interesting swarm occurred in Koryakia, Russian just during the last week of April and first week of May.

See - http://www.everything-science.com/component/option,com_smf/Itemid,82/topic,5244.msg59885#msg59885

 

[silkworm]

I've been watching this, and it seems as though Papua is getting hammered as the island had many +5.0 earthquakes in the last couple of days. Seismic activity is always more than what the average person expects, but it seems the ring of fire has been pretty moody the last couple of days.

I wish this was more detailed. There should be a lot more orange on Papua http://earthquake.usgs.gov/eqcenter/recenteqsww/Maps/region/Australia.php

Here's a list of recent +5.0 earthquakes there.
http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/quakes_big.php

Does anyone know of anything that measures the overall seismic activity of the planet?

 

[silkworm]

As a sidenote, as many as 5700 people have died so far as a result of Saturday's Indonesian quake, and 200,000 are displaced.

http://news.yahoo.com/s/afp/20060530/sc_afp/indonesiaquake_060530164756

 

[silkworm]

There's also this. A lot of times earthquakes trigger volcanos, and this story warns of that in the Indonesian quake.

JAKARTA (AFP) - Geologists have warned that simmering Mount Merapi volcano could blow its top in the wake of the powerful quake that devastated swathes of Indonesia's main island of Java...

...Quake activity near a dormant volcano may "switch it on," while already active volcanoes could see more intense rumblings, said the head of the office's department for disaster risk evaluation.

Since Saturday's 6.3-magnitude earthquake, seismologists have noted increased flows of lava and heat clouds at Merapi, just north of the temblor's epicentre.

Authorities had already issued a red alert ahead of a possible eruption and shelter camps were set up to house more than 24,000 people evacuated from its slopes...

http://news.yahoo.com/s/afp/20060530/sc_afp/indonesiaquakevolcanomerapi_060530111835

 

[quantumcarl]

The NorthWestCoast experiences 1000 earthquakes a year. Most of the shakers aren't noticed as they are deeper and at around 2-3.0 richter. This repetition of small quakes probably has delayed the occurance of a larger quake due to the fact that the pressure between the continental plate and the oceanic plates is released regularly by these smaller quakes.

I'm not sure if there is any rule to the frequency or the proximity of earthquakes. As Astonauc has pointed out... there are "swarms" of quakes. It must have to do with the activities going on in the "magma" of the earth.

We were watching the ball game in San Francisco on TV when that city was hit "on Tuesday, October 17, 1989 at 5:04 p.m. Pacific Daylight Time". Pretty eerie. Everything and everyone in the stadium started to sway then the camera and the network went blank. Totally out of touch in about 3 seconds. We had to use feed from other stations further to the north to find out what was going on in old SF.

"It was a magnitude 7.1 earthquake occurring on the San Andreas fault 10 miles northeast of Santa Cruz. This earthquake was the largest earthquake to occur in the San Francisco Bay area since 1906, and the largest anywhere in California since 1952. The earthquake was responsible for 67 deaths and about 7 billion dollars worth of damage."

If people still lived in clay or grass houses there would less personal loss due to earthquakes. As it is, our structures, even those structures in Indonesia, are what kill people, not the quakes themselves.

 

[Astronuc]

There's also this. A lot of times earthquakes trigger volcanos, and this story warns of that in the Indonesian quake.

I think that it is more the case that certain geologic activity (creep of the Earth's crust and flow of magma upward into the formation that forms the volcano causes the earthquakes. I don't believe volcanoes necessarily trigger earthquakes, unless the eruption releases considerable stress in one area that cause addition slippage of faults in the vicinity of the volcano.

 

[silkworm]

I think that it is more the case that certain geologic activity (creep of the Earth's crust and flow of magma upward into the formation that forms the volcano causes the earthquakes. I don't believe volcanoes necessarily trigger earthquakes, unless the eruption releases considerable stress in one area that cause addition slippage of faults in the vicinity of the volcano.

You mean that earthquakes don't necessarily trigger volcanos, right?

 

[Astronuc]

You mean that earthquakes don't necessarily trigger volcanos, right?

Not necessarily. Volcanoes are more or less thermal events, whereas earthquakes are primarily mechanical.

Now in areas like the Cascade mountain range in the US, it is believed that the mechanical energy of the subduction zone does cause tremendous heat - thermal energy - which leads to volcanoes, like Mt St Helens, Mt Hood, Mt Rainier, etc. And the subduction zone experiences earthquakes.

Merapi and the big earthquke near Yogyakarta are the direct consequence of the interaction between the Australian and Asian techtonic plates.

This map shows the historical seismicity in the section of Indonesia near Yogyakarta -
http://neic.usgs.gov/neis/eq_depot/2006/eq_060526_neb6/neic_neb6_h.html

The orange and yellow colors indicate shallow (and more destructive) earthqukes on the southern coast of Java. The blue and red indicate very deep earthquakes on the north side of Java. The Volcanoes in Indonesia are distributed along the southern side of Java and Indonesia.

http://www.volcano.si.edu/world/region.cfm?rnum=06

http://volcano.und.edu/vwdocs/volc_images/img_java1.html

http://www.volcano.si.edu/world/region.cfm?rnum=0603

As a country with 129 active volcanoes spreading across the archipelago, Indonesia has frequently suffered from natural disaster associated with volcanic eruption which happen at least once a year. Due to this volcanic risk, geographical and meteorological, an effective method of monitoring is required for those volcanoes.

The aim of all the monitoring methods is to reduce the impact of volcanic eruptions by establishing available early warnings, by mapping areas exposed to volcanological hazards,
and taking timely preventive measures.

Eighty of 129 volcanoes have been classified into A type according to their recorded-eruptions since 1600. Those are dotted across Sumatera (12 volcanoes), Java (21), Bali (2), Nusatenggara (20), Banda Sea (9), North Sulawesi (6), Sangihe (5)
and Halmahera (5).

http://www.vsi.esdm.go.id/volcanoes/index.htm
http://www.vsi.esdm.go.id/picture/index.html

 

[Integral]

I just saw a bit of a show today on Discovery Times, that they are now seeing evidence of "earthquake Storms" That is a series of quakes in a region over a period of years.http://www.bbc.co.uk/science/horizon/2003/earthquakestorms.shtml"

 

[silkworm]

Not necessarily. Volcanoes are more or less thermal events, whereas earthquakes are primarily mechanical.

Now in areas like the Cascade mountain range in the US, it is believed that the mechanical energy of the subduction zone does cause tremendous heat - thermal energy - which leads to volcanoes, like Mt St Helens, Mt Hood, Mt Rainier, etc. And the subduction zone experiences earthquakes.

Merapi and the big earthquke near Yogyakarta are the direct consequence of the interaction between the Australian and Asian techtonic plates.

This map shows the historical seismicity in the section of Indonesia near Yogyakarta -
http://neic.usgs.gov/neis/eq_depot/2006/eq_060526_neb6/neic_neb6_h.html

The orange and yellow colors indicate shallow (and more destructive) earthqukes on the southern coast of Java. The blue and red indicate very deep earthquakes on the north side of Java. The Volcanoes in Indonesia are distributed along the southern side of Java and Indonesia.

http://www.volcano.si.edu/world/region.cfm?rnum=06

http://volcano.und.edu/vwdocs/volc_images/img_java1.html

http://www.volcano.si.edu/world/region.cfm?rnum=0603

http://www.vsi.esdm.go.id/volcanoes/index.htm
http://www.vsi.esdm.go.id/picture/index.html

Righteous post. I just thought you mixed them up because I have heard of earthquakes occurring due to magma flow to the base of a volcano.

 

[Integral]

It may well be better to say that volcanos trigger earthquakes. The volcanologist track the magma flows events of Mt St Helens by watching for the very localized tremors which accomapany them. This may be what you have heard about.

The major earthquakes occur on fault lines associated with techtonic plates, volcanos appear on above the subtuction zones. In these regions the quakes and the volcanos are effects with a common cause, the subtuction zone. Some volcanoes, like Hawaii, appear to be associated with hot spots below the crust. A chain of volcanos is created as the tectonic plate moves over the hot spot. There is some evidence (saw it in a ~ '85 National Geographic) that Yellowstone is also a drifting "hot spot". Its geological footprints trace across Idaho,Utah, into Nevada and Oregon

 

[Ivan Seeking]

I just saw a bit of a show today on Discovery Times, that they are now seeing evidence of "earthquake Storms" That is a series of quakes in a region over a period of years.http://www.bbc.co.uk/science/horizon/2003/earthquakestorms.shtml"

Storms, swarms, that's what I was talking about.

 

[Astronuc]

Righteous post. I just thought you mixed them up because I have heard of earthquakes occurring due to magma flow to the base of a volcano.

Well, in a sense, earthqakes do occur in conjunctino with volcanoes, and perhaps one can think of stress-relief anneal. The hotter material is softer and flows. Softer material does not provide adquate mechanical restraint, and if rock flows, then somewhere else, stress builds until it is relieved by an earthquake.

The crust of the Earth is very dynamic on huge scales. Some locations/regions are much more dynamic.

I believe seismic/volcanic activity has increased during the last two years in the Western Pacific and the extension across Indonesia into the Indian Ocean. The consequences are the very strong earthquakes near norther Sumatra (Aceh) and Pakistan. All this is associated with the Australian and Pacific Plates (and some minor plates in between) interacting with the Asian Plate.