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Earthquake Studies...

#1 · June 25, 2020, 7:22 am

Quote from smAsh on June 25, 2020, 7:22 am
This study brings up interesting hypotheses about 'original water' being generated within the Earth. Without getting in-depth into those ideas, feel free to contribute to this and any other threads in which you are interested. Thanks website members, please tell your friends, foes and neutrals.

JUNE 24, 2020
New research reveals how water in the deep Earth triggers earthquakes and tsunamis
by University of Bristol
Quill, on the island of Statia. One of the islands in the Lesser Antilles. Credit: Dr George Cooper
In a new study, published in the journal Nature, an international team of scientists provide the first conclusive evidence directly linking deep Earth's water cycle and its expressions with magmatic productivity and earthquake activity.
Water (H₂O) and other volatiles (e.g. CO₂ and sulphur) that are cycled through the deep Earth have played a key role in the evolution of our planet, including in the formation of continents, the onset of life, the concentration of mineral resources, and the distribution of volcanoes and earthquakes.
Subduction zones, where tectonic plates converge and one plate sinks beneath another, are the most important parts of the cycle—with large volumes of water going in and coming out, mainly through volcanic eruptions. Yet, just how (and how much) water is transported via subduction, and its effect on natural hazards and the formation of natural resources, has historically been poorly understood.
Lead author of the study, Dr. George Cooper, Honorary Research Fellow at the University of Bristol's School of Earth Sciences, said:"As plates journey from where they are first made at mid-ocean ridges to subduction zones, seawater enters the rocks through cracks, faults and by binding to minerals. Upon reaching a subduction zone, the sinking plate heats up and gets squeezed, resulting in the gradual release of some or all of its water. As water is released it lowers the melting point of the surrounding rocks and generates magma. This magma is buoyant and moves upwards, ultimately leading to eruptions in the overlying volcanic arc. These eruptions are potentially explosive because of the volatiles contained in the melt. The same process can trigger earthquakes and may affect key properties such as their magnitude and whether they trigger tsunamis or not."
Exactly where and how volatiles are released and how they modify the host rock remains an area of intense research.
Most studies have focused on subduction along the Pacific Ring of Fire. However, this research focused on the Atlantic plate, and more specifically, the Lesser Antilles volcanic arc, located at the eastern edge of the Caribbean Sea.

"This is one of only two zones that currently subduct plates formed by slow spreading. We expect this to be hydrated more pervasively and heterogeneously than the fast spreading Pacific plate, and for expressions of water release to be more pronounced," said Prof. Saskia Goes, Imperial College London.
The Volatile Recycling in the Lesser Antilles (VoiLA) project brings together a large multidisciplinary team of researchers including geophysicists, geochemists and geodynamicists from Durham University, Imperial College London, University of Southampton, University of Bristol, Liverpool University, Karlsruhe Institute of Technology, the University of Leeds, The Natural History Museum, The Institute de Physique du Globe in Paris, and the University of the West Indies.
"We collected data over two marine scientific cruises on the RRS James Cook, temporary deployments of seismic stations that recorded earthquakes beneath the islands, geological fieldwork, chemical and mineral analyses of rock samples, and numerical modelling," said Dr. Cooper.
To trace the influence of water along the length of the subduction zone, the scientists studied boron compositions and isotopes of melt inclusions (tiny pockets of trapped magma within volcanic crystals). Boron fingerprints revealed that the water-rich mineral serpentine, contained in the sinking plate, is a dominant supplier of water to the central region of the Lesser Antilles arc.
"By studying these micron-scale measurements it is possible to better understand large-scale processes. Our combined geochemical and geophysical data provide the clearest indication to date that the structure and amount of water of the sinking plate are directly connected to the volcanic evolution of the arc and its associated hazards," said Prof. Colin Macpherson, Durham University
"The wettest parts of the downgoing plate are where there are major cracks (or fracture zones). By making a numerical model of the history of fracture zone subduction below the islands, we found a direct link to the locations of the highest rates of small earthquakes and low shear wave velocities (which indicate fluids) in the subsurface," said Prof. Saskia Goes.
The history of subduction of water-rich fracture zones can also explain why the central islands of the arc are the largest and why, over geologic history, they have produced the most magma.
"Our study provides conclusive evidence that directly links the water-in and water-out parts of the cycle and its expressions in terms of magmatic productivity and earthquake activity. This may encourage studies at other subduction zones to find such water-bearing fault structures on the subducting plate to help understand patterns in volcanic and earthquake hazards," said Dr. Cooper.
"In this research we found that variations in water correlate with the distribution of smaller earthquakes, but we would really like to know how this pattern of water release may affect the potential—and act as a warning system—for larger earthquakes and possible tsunami," said Prof. Colin Macpherson.
source: phys.org

This study brings up interesting hypotheses about 'original water' being generated within the Earth. Without getting in-depth into those ideas, feel free to contribute to this and any other threads in which you are interested. Thanks website members, please tell your friends, foes and neutrals.

JUNE 24, 2020

New research reveals how water in the deep Earth triggers earthquakes and tsunamis

by University of Bristol

Quill, on the island of Statia. One of the islands in the Lesser Antilles. Credit: Dr George Cooper

In a new study, published in the journal Nature, an international team of scientists provide the first conclusive evidence directly linking deep Earth's water cycle and its expressions with magmatic productivity and earthquake activity.

Water (H₂O) and other volatiles (e.g. CO₂ and sulphur) that are cycled through the deep Earth have played a key role in the evolution of our planet, including in the formation of continents, the onset of life, the concentration of mineral resources, and the distribution of volcanoes and earthquakes.

Subduction zones, where tectonic plates converge and one plate sinks beneath another, are the most important parts of the cycle—with large volumes of water going in and coming out, mainly through volcanic eruptions. Yet, just how (and how much) water is transported via subduction, and its effect on natural hazards and the formation of natural resources, has historically been poorly understood.

Lead author of the study, Dr. George Cooper, Honorary Research Fellow at the University of Bristol's School of Earth Sciences, said:"As plates journey from where they are first made at mid-ocean ridges to subduction zones, seawater enters the rocks through cracks, faults and by binding to minerals. Upon reaching a subduction zone, the sinking plate heats up and gets squeezed, resulting in the gradual release of some or all of its water. As water is released it lowers the melting point of the surrounding rocks and generates magma. This magma is buoyant and moves upwards, ultimately leading to eruptions in the overlying volcanic arc. These eruptions are potentially explosive because of the volatiles contained in the melt. The same process can trigger earthquakes and may affect key properties such as their magnitude and whether they trigger tsunamis or not."

Exactly where and how volatiles are released and how they modify the host rock remains an area of intense research.

Most studies have focused on subduction along the Pacific Ring of Fire. However, this research focused on the Atlantic plate, and more specifically, the Lesser Antilles volcanic arc, located at the eastern edge of the Caribbean Sea.

"This is one of only two zones that currently subduct plates formed by slow spreading. We expect this to be hydrated more pervasively and heterogeneously than the fast spreading Pacific plate, and for expressions of water release to be more pronounced," said Prof. Saskia Goes, Imperial College London.

The Volatile Recycling in the Lesser Antilles (VoiLA) project brings together a large multidisciplinary team of researchers including geophysicists, geochemists and geodynamicists from Durham University, Imperial College London, University of Southampton, University of Bristol, Liverpool University, Karlsruhe Institute of Technology, the University of Leeds, The Natural History Museum, The Institute de Physique du Globe in Paris, and the University of the West Indies.

"We collected data over two marine scientific cruises on the RRS James Cook, temporary deployments of seismic stations that recorded earthquakes beneath the islands, geological fieldwork, chemical and mineral analyses of rock samples, and numerical modelling," said Dr. Cooper.

To trace the influence of water along the length of the subduction zone, the scientists studied boron compositions and isotopes of melt inclusions (tiny pockets of trapped magma within volcanic crystals). Boron fingerprints revealed that the water-rich mineral serpentine, contained in the sinking plate, is a dominant supplier of water to the central region of the Lesser Antilles arc.

"By studying these micron-scale measurements it is possible to better understand large-scale processes. Our combined geochemical and geophysical data provide the clearest indication to date that the structure and amount of water of the sinking plate are directly connected to the volcanic evolution of the arc and its associated hazards," said Prof. Colin Macpherson, Durham University

"The wettest parts of the downgoing plate are where there are major cracks (or fracture zones). By making a numerical model of the history of fracture zone subduction below the islands, we found a direct link to the locations of the highest rates of small earthquakes and low shear wave velocities (which indicate fluids) in the subsurface," said Prof. Saskia Goes.

The history of subduction of water-rich fracture zones can also explain why the central islands of the arc are the largest and why, over geologic history, they have produced the most magma.

"Our study provides conclusive evidence that directly links the water-in and water-out parts of the cycle and its expressions in terms of magmatic productivity and earthquake activity. This may encourage studies at other subduction zones to find such water-bearing fault structures on the subducting plate to help understand patterns in volcanic and earthquake hazards," said Dr. Cooper.

"In this research we found that variations in water correlate with the distribution of smaller earthquakes, but we would really like to know how this pattern of water release may affect the potential—and act as a warning system—for larger earthquakes and possible tsunami," said Prof. Colin Macpherson.

source: phys.org

Mary Wright has reacted to this post.

Regards, Dan, a. k. a. smAshomAsh

#2 · June 25, 2020, 11:25 am

Superionic ice , black ice 18 XVIII oxygen solid hexagonal lattice with flowing liquid hydrogen inside of it. It's both liquid and solid simultaneously if a planet were for example an gas giant and lost much of it's mass the very stable ice 18 could still maintain with leeking and melting over period of time due to pressure loss and thus the 4x less dense water is gradually released from these crystals. Taking up more volume and adding to our Earth and creating mention subduction regions and cycles relating to earthquakes and various other space related details.

https://www.quantamagazine.org/black-hot-superionic-ice-may-be-natures-most-common-form-of-water-20190508/

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○°| Making the world obvious in not so obvious ways connecting patterns and associating Aincent pasts gods as symbolic personification of very complex ideals in physics, atomics, cosmology etc. Taking folklore and learning the subtext the esoterical data preserved in the complex nature like intentional to keep the memory alive over many many many generations. Data is gathered sometimes through a process of creative writing where I'm pretend to believe that unimportant information is vital and relevant and use overactive imagination to understand various outcomes that lead to ultimately accurate conclusions and new ideals no one has considered. Sometimes this process I call being creatively precautious. As you are aware but not simultaneously it's a near manic but not emotional state that's helps me with my esoterical portion of my bestowic behavior. Information metadata seemingly not yet important but truly underlying geometrical and core structure of messages and symbols are relevant. ●•|

#3 · June 25, 2020, 11:33 am

This is a must read found tonight released 17 hours ago.

https://eos.org/features/remaking-a-planet-one-atom-at-a-time

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#4 · June 26, 2020, 8:03 am

Quote from Bestowic on June 25, 2020, 11:25 am
Superionic ice , black ice 18 XVIII oxygen solid hexagonal lattice with flowing liquid hydrogen inside of it. It's both liquid and solid simultaneously if a planet were for example an gas giant and lost much of it's mass the very stable ice 18 could still maintain with leeking and melting over period of time due to pressure loss and thus the 4x less dense water is gradually released from these crystals. Taking up more volume and adding to our Earth and creating mention subduction regions and cycles relating to earthquakes and various other space related details.
https://www.quantamagazine.org/black-hot-superionic-ice-may-be-natures-most-common-form-of-water-20190508/

Funky!

Quote from Bestowic on June 25, 2020, 11:33 am
This is a must read found tonight released 17 hours ago.

https://eos.org/features/remaking-a-planet-one-atom-at-a-time

Funky fresh! -(Run D.M.C)

Mary Wright has reacted to this post.

Regards, Dan, a. k. a. smAshomAsh

#5 · July 27, 2020, 8:31 am

https://www.nature.com/articles/s41598-020-67860-3#auth-2

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#6 · September 9, 2020, 11:34 am

This is in reference to the New Jersey earthquake that you mentioned in today's video yes that is weird but I followed a pattern and I've been waiting for more conclusive evidence about the method that I use to protect earthquakes when I see an earthquake an anomalous area I do a search for approximately the same magnitude in the same region and then I take that date of that anomalous recorded earthquake and then I do a plus and minus 2 months sometimes 3 months of the earthquakes of that. And it has worked phenomenally. The photo is a screenshot from 3 days ago where I said that the East coast would be hit likely New York area. I've done this many times in messenger with a mutual friend and viewer I think that this should be exploited using the USGS and anomalous earthquake zones to make future predictions of likelihood of earthquakes in the next coming months.

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#7 · September 19, 2020, 12:32 am

Quote from Bestowic on September 19, 2020, 12:32 am
Based on the mid central atlantic 6.9 I located a date range from Jan 2008 to june 2008 here is list of 6+

place mag time latitude longitude depth
eastern Sichuan, China 7.9 2008-05-12T06:28:01.570Z 31.002 103.322 19
Simeulue, Indonesia 7.4 2008-02-20T08:08:30.520Z 2.768 95.964 26
Loyalty Islands, New Caledonia 7.3 2008-04-09T12:46:12.720Z -20.071 168.892 33
Kepulauan Mentawai region, Indonesia 7.2 2008-02-25T08:36:33.030Z -2.486 99.972 25
Xinjiang-Xizang border region 7.2 2008-03-20T22:32:57.930Z 35.49 81.467 10
Macquarie Island region 7.1 2008-04-12T00:30:12.600Z -55.664 158.453 16
northern Mid-Atlantic Ridge 6.9 2008-02-08T09:38:14.100Z 10.671 -41.899 9
Philippine Islands region 6.9 2008-03-03T14:11:14.620Z 13.351 125.63 24
southern Greece 6.9 2008-02-14T10:09:22.720Z 36.501 21.67 29
near the east coast of Honshu, Japan 6.9 2008-05-07T16:45:18.700Z 36.164 141.526 27
eastern Honshu, Japan 6.9 2008-06-13T23:43:45.360Z 39.03 140.881 7.8
South Sandwich Islands region 6.8 2008-02-23T15:57:20.490Z -57.335 -23.433 14
Guam region 6.8 2008-05-09T21:51:29.730Z 12.516 143.181 76
Kepulauan Mentawai region, Indonesia 6.7 2008-02-25T21:02:18.420Z -2.245 99.808 25
South Sandwich Islands region 6.6 2008-02-10T12:22:02.650Z -60.797 -25.586 8
Kepulauan Mentawai region, Indonesia 6.6 2008-02-25T18:06:03.900Z -2.332 99.891 25
Andreanof Islands, Aleutian Islands, Alaska 6.6 2008-04-16T05:54:19.690Z 51.878 -179.165 13
Andreanof Islands, Aleutian Islands, Alaska 6.6 2008-05-02T01:33:37.240Z 51.864 -177.528 14
Haida Gwaii Region, Canada 6.6 2008-01-05T11:01:06.110Z 51.254 -130.746 15
Fiji region 6.5 2008-01-15T17:52:15.690Z -21.984 -179.535 597.6
Oaxaca, Mexico 6.5 2008-02-12T12:50:18.490Z 16.357 -94.304 83
southern Greece 6.5 2008-02-14T12:08:55.790Z 36.345 21.863 28
Kepulauan Mentawai region, Indonesia 6.5 2008-02-24T14:46:21.470Z -2.405 99.931 22
Kuril Islands 6.5 2008-03-03T09:31:02.500Z 46.406 153.175 10
central Mid-Atlantic Ridge 6.5 2008-04-24T12:14:49.920Z -1.182 -23.471 10
central Mid-Atlantic Ridge 6.5 2008-05-23T19:35:34.780Z 7.313 -34.897 8
west of Macquarie Island 6.5 2008-06-01T14:31:03.010Z -59.384 149.66 10
Haida Gwaii Region, Canada 6.4 2008-01-05T11:44:48.170Z 51.163 -130.542 10
western Xizang 6.4 2008-01-09T08:26:45.490Z 32.288 85.166 10
Vanuatu 6.4 2008-03-12T11:23:34.060Z -16.567 167.335 13
Loyalty Islands, New Caledonia 6.4 2008-04-09T11:13:17.690Z -20.175 168.861 16
Andreanof Islands, Aleutian Islands, Alaska 6.4 2008-04-15T22:59:51.500Z 51.856 -179.361 11
Vanuatu 6.4 2008-04-28T18:33:34.200Z -19.941 168.953 32
Mid-Indian Ridge 6.4 2008-05-31T04:37:56.010Z -41.198 80.479 9
southern Greece 6.4 2008-06-08T12:25:29.710Z 37.963 21.525 16
eastern New Guinea region, Papua New Guinea 6.3 2008-01-01T18:54:59.010Z -5.878 146.884 34
off the coast of Oregon 6.3 2008-01-10T01:37:19.000Z 43.785 -127.264 13
Tarapaca, Chile 6.3 2008-02-04T17:01:29.980Z -20.166 -70.037 35
Vanuatu 6.3 2008-03-12T11:36:55.280Z -16.489 167.183 10
Simeulue, Indonesia 6.3 2008-03-29T17:30:50.150Z 2.855 95.296 20
Loyalty Islands, New Caledonia 6.3 2008-04-09T11:23:40.350Z -20.185 168.905 35
Vanuatu 6.3 2008-04-09T14:47:50.510Z -19.997 168.874 35
Tonga 6.3 2008-04-16T00:35:48.870Z -18.609 -175.699 10
Fiji region 6.3 2008-04-18T20:39:07.140Z -17.342 -179.022 553.8
Loyalty Islands, New Caledonia 6.3 2008-04-19T05:58:42.250Z -20.273 168.796 14
Rat Islands, Aleutian Islands, Alaska 6.3 2008-05-20T13:53:35.640Z 51.162 178.759 27
Iceland 6.3 2008-05-29T15:46:00.320Z 64.005 -21.013 9
Batan Islands region, Philippines 6.3 2008-06-01T01:57:23.690Z 20.124 121.35 31
Nias region, Indonesia 6.2 2008-01-22T17:14:57.950Z 1.011 97.442 20
Kepulauan Barat Daya, Indonesia 6.2 2008-01-30T07:32:42.800Z -7.302 127.688 8
Timor Sea 6.2 2008-02-13T19:58:46.130Z -8.158 128.644 19
southern Greece 6.2 2008-02-20T18:27:06.000Z 36.288 21.775 9.9
Bonin Islands, Japan region 6.2 2008-02-27T06:54:20.610Z 26.816 142.438 15
Kepulauan Mentawai region, Indonesia 6.2 2008-03-03T02:37:27.120Z -2.18 99.823 25
Kermadec Islands, New Zealand 6.2 2008-03-18T08:22:47.070Z -29.252 -177.44 25
Andreanof Islands, Aleutian Islands, Alaska 6.2 2008-03-22T21:24:11.270Z 52.176 -178.716 132
near the east coast of Honshu, Japan 6.2 2008-05-07T16:02:02.600Z 36.178 141.545 19
southern Greece 6.2 2008-01-06T05:14:20.180Z 37.216 22.693 75
Tarapaca, Chile 6.2 2008-03-24T20:39:07.630Z -20.043 -68.963 120
Solomon Islands 6.2 2008-06-03T16:20:50.380Z -10.509 161.273 84
Haida Gwaii Region, Canada 6.1 2008-01-09T14:40:00.960Z 51.649 -131.183 10
Molucca Sea 6.1 2008-01-20T20:26:04.880Z 2.346 126.816 35
Tonga 6.1 2008-01-22T10:49:21.800Z -15.419 -175.589 10
Antofagasta, Chile 6.1 2008-02-16T14:45:11.690Z -21.346 -68.385 130.1
Loyalty Islands, New Caledonia 6.1 2008-04-11T17:45:01.940Z -20.392 168.839 11
offshore Guatemala 6.1 2008-04-15T03:03:04.660Z 13.564 -90.599 33
Kepulauan Barat Daya, Indonesia 6.1 2008-04-19T03:12:25.180Z -7.815 125.694 13
Auckland Islands, New Zealand region 6.1 2008-04-26T23:34:49.390Z -49.091 164.117 10
South Sandwich Islands region 6.1 2008-04-28T15:57:55.280Z -58.739 -24.714 35
Loyalty Islands, New Caledonia 6.1 2008-04-28T20:26:53.110Z -20.238 168.824 35
Sichuan-Gansu border region, China 6.1 2008-05-25T08:21:49.990Z 32.56 105.423 18
Mindanao, Philippines 6.1 2008-03-20T14:10:40.400Z 6.192 126.934 45
Svalbard region 6.1 2008-02-21T02:46:18.190Z 77.079 18.571 12
eastern Sichuan, China 6.1 2008-05-12T11:11:02.480Z 31.214 103.618 10
near the east coast of Honshu, Japan 6.1 2008-05-07T16:16:36.190Z 36.156 141.756 23.3
Tonga 6 2008-01-22T07:55:48.880Z -15.277 -175.348 6
Fiji region 6 2008-02-01T12:10:06.400Z -21.495 -179.352 604.2
Molucca Sea 6 2008-02-09T18:34:01.600Z -0.236 125.084 38
Prince Edward Islands region 6 2008-03-13T13:28:44.850Z -45.492 35.008 10
Bonin Islands, Japan region 6 2008-03-14T22:32:09.380Z 26.988 142.599 10
off the west coast of northern Sumatra 6 2008-03-15T14:43:26.500Z 2.708 94.596 25
South Sandwich Islands region 6 2008-04-14T09:45:19.700Z -56.022 -28.035 140.2
Kepulauan Barat Daya, Indonesia 6 2008-04-19T10:21:12.500Z -7.875 125.722 10
Taiwan region 6 2008-04-23T18:28:41.880Z 22.881 121.619 10
northern Sumatra, Indonesia 6 2008-05-19T14:26:45.020Z 1.64 99.147 10
south of Alaska 6 2008-05-25T19:18:24.384Z 55.9055 -153.5083 20
Flores region, Indonesia 6 2008-06-03T22:04:27.870Z -8.1 120.231 14
West Chile Rise 6 2008-06-05T02:16:46.930Z -38.844 -91.623 10
Kepulauan Barat Daya, Indonesia 6 2008-06-06T13:42:48.950Z -7.495 127.885 122
southern East Pacific Rise 6 2008-06-15T08:37:17.200Z -36.623 -107.45 10
Babuyan Islands region, Philippines 6 2008-03-03T13:49:40.420Z 19.913 121.334 10
southern Sumatra, Indonesia 6 2008-01-04T07:29:18.300Z -2.782 101.032 35

Based on the mid central atlantic 6.9 I located a date range from Jan 2008 to june 2008 here is list of 6+

place	mag	time	latitude	longitude	depth
eastern Sichuan, China	7.9	2008-05-12T06:28:01.570Z	31.002	103.322	19
Simeulue, Indonesia	7.4	2008-02-20T08:08:30.520Z	2.768	95.964	26
Loyalty Islands, New Caledonia	7.3	2008-04-09T12:46:12.720Z	-20.071	168.892	33
Kepulauan Mentawai region, Indonesia	7.2	2008-02-25T08:36:33.030Z	-2.486	99.972	25
Xinjiang-Xizang border region	7.2	2008-03-20T22:32:57.930Z	35.49	81.467	10
Macquarie Island region	7.1	2008-04-12T00:30:12.600Z	-55.664	158.453	16
northern Mid-Atlantic Ridge	6.9	2008-02-08T09:38:14.100Z	10.671	-41.899	9
Philippine Islands region	6.9	2008-03-03T14:11:14.620Z	13.351	125.63	24
southern Greece	6.9	2008-02-14T10:09:22.720Z	36.501	21.67	29
near the east coast of Honshu, Japan	6.9	2008-05-07T16:45:18.700Z	36.164	141.526	27
eastern Honshu, Japan	6.9	2008-06-13T23:43:45.360Z	39.03	140.881	7.8
South Sandwich Islands region	6.8	2008-02-23T15:57:20.490Z	-57.335	-23.433	14
Guam region	6.8	2008-05-09T21:51:29.730Z	12.516	143.181	76
Kepulauan Mentawai region, Indonesia	6.7	2008-02-25T21:02:18.420Z	-2.245	99.808	25
South Sandwich Islands region	6.6	2008-02-10T12:22:02.650Z	-60.797	-25.586	8
Kepulauan Mentawai region, Indonesia	6.6	2008-02-25T18:06:03.900Z	-2.332	99.891	25
Andreanof Islands, Aleutian Islands, Alaska	6.6	2008-04-16T05:54:19.690Z	51.878	-179.165	13
Andreanof Islands, Aleutian Islands, Alaska	6.6	2008-05-02T01:33:37.240Z	51.864	-177.528	14
Haida Gwaii Region, Canada	6.6	2008-01-05T11:01:06.110Z	51.254	-130.746	15
Fiji region	6.5	2008-01-15T17:52:15.690Z	-21.984	-179.535	597.6
Oaxaca, Mexico	6.5	2008-02-12T12:50:18.490Z	16.357	-94.304	83
southern Greece	6.5	2008-02-14T12:08:55.790Z	36.345	21.863	28
Kepulauan Mentawai region, Indonesia	6.5	2008-02-24T14:46:21.470Z	-2.405	99.931	22
Kuril Islands	6.5	2008-03-03T09:31:02.500Z	46.406	153.175	10
central Mid-Atlantic Ridge	6.5	2008-04-24T12:14:49.920Z	-1.182	-23.471	10
central Mid-Atlantic Ridge	6.5	2008-05-23T19:35:34.780Z	7.313	-34.897	8
west of Macquarie Island	6.5	2008-06-01T14:31:03.010Z	-59.384	149.66	10
Haida Gwaii Region, Canada	6.4	2008-01-05T11:44:48.170Z	51.163	-130.542	10
western Xizang	6.4	2008-01-09T08:26:45.490Z	32.288	85.166	10
Vanuatu	6.4	2008-03-12T11:23:34.060Z	-16.567	167.335	13
Loyalty Islands, New Caledonia	6.4	2008-04-09T11:13:17.690Z	-20.175	168.861	16
Andreanof Islands, Aleutian Islands, Alaska	6.4	2008-04-15T22:59:51.500Z	51.856	-179.361	11
Vanuatu	6.4	2008-04-28T18:33:34.200Z	-19.941	168.953	32
Mid-Indian Ridge	6.4	2008-05-31T04:37:56.010Z	-41.198	80.479	9
southern Greece	6.4	2008-06-08T12:25:29.710Z	37.963	21.525	16
eastern New Guinea region, Papua New Guinea	6.3	2008-01-01T18:54:59.010Z	-5.878	146.884	34
off the coast of Oregon	6.3	2008-01-10T01:37:19.000Z	43.785	-127.264	13
Tarapaca, Chile	6.3	2008-02-04T17:01:29.980Z	-20.166	-70.037	35
Vanuatu	6.3	2008-03-12T11:36:55.280Z	-16.489	167.183	10
Simeulue, Indonesia	6.3	2008-03-29T17:30:50.150Z	2.855	95.296	20
Loyalty Islands, New Caledonia	6.3	2008-04-09T11:23:40.350Z	-20.185	168.905	35
Vanuatu	6.3	2008-04-09T14:47:50.510Z	-19.997	168.874	35
Tonga	6.3	2008-04-16T00:35:48.870Z	-18.609	-175.699	10
Fiji region	6.3	2008-04-18T20:39:07.140Z	-17.342	-179.022	553.8
Loyalty Islands, New Caledonia	6.3	2008-04-19T05:58:42.250Z	-20.273	168.796	14
Rat Islands, Aleutian Islands, Alaska	6.3	2008-05-20T13:53:35.640Z	51.162	178.759	27
Iceland	6.3	2008-05-29T15:46:00.320Z	64.005	-21.013	9
Batan Islands region, Philippines	6.3	2008-06-01T01:57:23.690Z	20.124	121.35	31
Nias region, Indonesia	6.2	2008-01-22T17:14:57.950Z	1.011	97.442	20
Kepulauan Barat Daya, Indonesia	6.2	2008-01-30T07:32:42.800Z	-7.302	127.688	8
Timor Sea	6.2	2008-02-13T19:58:46.130Z	-8.158	128.644	19
southern Greece	6.2	2008-02-20T18:27:06.000Z	36.288	21.775	9.9
Bonin Islands, Japan region	6.2	2008-02-27T06:54:20.610Z	26.816	142.438	15
Kepulauan Mentawai region, Indonesia	6.2	2008-03-03T02:37:27.120Z	-2.18	99.823	25
Kermadec Islands, New Zealand	6.2	2008-03-18T08:22:47.070Z	-29.252	-177.44	25
Andreanof Islands, Aleutian Islands, Alaska	6.2	2008-03-22T21:24:11.270Z	52.176	-178.716	132
near the east coast of Honshu, Japan	6.2	2008-05-07T16:02:02.600Z	36.178	141.545	19
southern Greece	6.2	2008-01-06T05:14:20.180Z	37.216	22.693	75
Tarapaca, Chile	6.2	2008-03-24T20:39:07.630Z	-20.043	-68.963	120
Solomon Islands	6.2	2008-06-03T16:20:50.380Z	-10.509	161.273	84
Haida Gwaii Region, Canada	6.1	2008-01-09T14:40:00.960Z	51.649	-131.183	10
Molucca Sea	6.1	2008-01-20T20:26:04.880Z	2.346	126.816	35
Tonga	6.1	2008-01-22T10:49:21.800Z	-15.419	-175.589	10
Antofagasta, Chile	6.1	2008-02-16T14:45:11.690Z	-21.346	-68.385	130.1
Loyalty Islands, New Caledonia	6.1	2008-04-11T17:45:01.940Z	-20.392	168.839	11
offshore Guatemala	6.1	2008-04-15T03:03:04.660Z	13.564	-90.599	33
Kepulauan Barat Daya, Indonesia	6.1	2008-04-19T03:12:25.180Z	-7.815	125.694	13
Auckland Islands, New Zealand region	6.1	2008-04-26T23:34:49.390Z	-49.091	164.117	10
South Sandwich Islands region	6.1	2008-04-28T15:57:55.280Z	-58.739	-24.714	35
Loyalty Islands, New Caledonia	6.1	2008-04-28T20:26:53.110Z	-20.238	168.824	35
Sichuan-Gansu border region, China	6.1	2008-05-25T08:21:49.990Z	32.56	105.423	18
Mindanao, Philippines	6.1	2008-03-20T14:10:40.400Z	6.192	126.934	45
Svalbard region	6.1	2008-02-21T02:46:18.190Z	77.079	18.571	12
eastern Sichuan, China	6.1	2008-05-12T11:11:02.480Z	31.214	103.618	10
near the east coast of Honshu, Japan	6.1	2008-05-07T16:16:36.190Z	36.156	141.756	23.3
Tonga	6	2008-01-22T07:55:48.880Z	-15.277	-175.348	6
Fiji region	6	2008-02-01T12:10:06.400Z	-21.495	-179.352	604.2
Molucca Sea	6	2008-02-09T18:34:01.600Z	-0.236	125.084	38
Prince Edward Islands region	6	2008-03-13T13:28:44.850Z	-45.492	35.008	10
Bonin Islands, Japan region	6	2008-03-14T22:32:09.380Z	26.988	142.599	10
off the west coast of northern Sumatra	6	2008-03-15T14:43:26.500Z	2.708	94.596	25
South Sandwich Islands region	6	2008-04-14T09:45:19.700Z	-56.022	-28.035	140.2
Kepulauan Barat Daya, Indonesia	6	2008-04-19T10:21:12.500Z	-7.875	125.722	10
Taiwan region	6	2008-04-23T18:28:41.880Z	22.881	121.619	10
northern Sumatra, Indonesia	6	2008-05-19T14:26:45.020Z	1.64	99.147	10
south of Alaska	6	2008-05-25T19:18:24.384Z	55.9055	-153.5083	20
Flores region, Indonesia	6	2008-06-03T22:04:27.870Z	-8.1	120.231	14
West Chile Rise	6	2008-06-05T02:16:46.930Z	-38.844	-91.623	10
Kepulauan Barat Daya, Indonesia	6	2008-06-06T13:42:48.950Z	-7.495	127.885	122
southern East Pacific Rise	6	2008-06-15T08:37:17.200Z	-36.623	-107.45	10
Babuyan Islands region, Philippines	6	2008-03-03T13:49:40.420Z	19.913	121.334	10
southern Sumatra, Indonesia	6	2008-01-04T07:29:18.300Z	-2.782	101.032	35

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#8 · October 10, 2020, 7:14 am

Quote from smAsh on October 10, 2020, 7:14 am
Textbooks and Geoscientists May Be Wrong About How the Alps Were Formed
TOPICS:ETH Zurich Geology Geophysics Popular Tectonic Plates
By ETH ZURICH OCTOBER 3, 2020
Central Alps of Switzerland have been lifted to today’s height. Credit: ETH Zurich
ETH researchers have used a computer model to test a new hypothesis about the formation of the Alps while simulating seismic activity in Switzerland. This will help improve current earthquake risk models.
For a long time, geoscientists have assumed that the Alps were formed when the Adriatic plate from the south collided with the Eurasian plate in the north. According to the textbooks, the Adriatic plate behaved like a bulldozer, thrusting rock material up in front of it into piles that formed the mountains. Supposedly, their weight subsequently pushed the underlying continental plate downwards, resulting in the formation of a sedimentary basin in the north adjacent to the mountains – the Swiss Molasse Plateau. Over time, while the mountains grew higher the basin floor sank deeper and deeper with the rest of the plate.
A few years ago, however, new geophysical and geological data led ETH geophysicist Edi Kissling and Fritz Schlunegger, a sediment specialist from the University of Bern, to express doubts about this theory. In light of the new information, the researchers postulated an alternative mechanism for the formation of the Alps.
Altitude of the Alps has barely changed
Kissling and Schlunegger pointed out that the topography and altitude of the Alps have barely changed over the past 30 million years, and yet the trench at the site of the Swiss Plateau has continued to sink and the basin extended further north. This leads the researchers to believe that the formation of the Central Alps and the sinking of the trench are not connected as previously assumed. They argue that if the Alps and the trench indeed had formed from the impact of two plates pressing together, there would be clear indications that the Alps were steadily growing. That’s because, based on the earlier understanding of how the Alps formed, the collision of the plates, the formation of the trench and the height of the mountain range are all linked. Furthermore, seismicity observed during the past 40 years within the Swiss Alps and their northern foreland clearly documents extension across the mountain ranges rather than the compression expected for the bulldozing Adria model.
The behavior of the Eurasian plate provides a possible new explanation. Since about 60 Ma ago, the former oceanic part of the Eurasian plate sinks beneath the continental Adriatic microplate in the south. By about 30 Ma ago, this process of subduction is so far advanced that all oceanic lithosphere has been consumed and the continental part of the Eurasian plate enters the subduction zone. This denotes the begin of the so-called continent-continent collision with the Adriatic microplate and the European upper, lighter crust separates from the heavier, underlying lithospheric mantle. Because it weighs less, the Earth’s crust surges upwards, literally creating the Alps for the first time around 30 Ma ago. While this is happening, the lithospheric mantle sinks further into the Earth’s mantle, thus pulling the adjacent part of the plate downwards.
This theory is plausible because the Alps are mainly made up of gneiss and granite and their sedimentary cover rocks like limestone. These crustal rocks are significantly lighter than the Earth’s mantle – into which the lower layer of the plate, the lithospheric mantle, plunges after the detachment of the two layers that form the continental plate. “In turn, this creates strong upward forces that lift the Alps out of the ground,” Kissling explains. “It was these upward forces that caused the Alps to form, not the bulldozer effect as a result of two continental plates colliding,” he says.
New model confirms lift hypothesis
To investigate the lift hypothesis, Luca Dal Zilio, former doctoral student in ETH geophysics professor Taras Gerya’s group, has now teamed up with Kissling and other ETH researchers to develop a new model. Dal Zilio used ETH’s Euler mainframe to simulate the subduction zone under the Alps: the plate tectonic processes, which took place over millions of years, and the associated earthquakes.
“The big challenge with this model was bridging the time scales. It takes into account lightning-fast shifts that manifest themselves in the form of earthquakes, as well as deformations of the crust and lithospheric mantle over thousands of years,” says Dal Zilio, lead author of the study recently published in the journal Geophysical Review Letters.
Five important stages in the orogeny:
Thirty-seven million years ago, subduction of the heavier oceanic part of the Eurasian Plate (from the left) under the lighter continental Adriatic Plate (right) in the south is in full swing. A shallow “mountain range” (yellow, striped area) forms above the zone where the plates converge, initially as isolated islands that barely protrude above sea level. Light green area: Earth’s mantle; green band: lithosphere; dark green, narrow band: oceanic crust; pink/ruby red bands: lower crust; grey bands: upper crust.
Over millions of years, the oceanic plate becomes increasingly curved, practically curling in on itself. The Eurasian plate as a whole remains stationary. This causes the subducting plate to start exerting a suction effect on the much smaller Adriatic plate, pulling it northwards (to the left in the diagram).
Continent-Continent Collision. When this process of subduction is so far advanced that the lighter, continental part of the Eurasian plate enters the subduction zone and begins to collide with the Adriatic microplate, the subduction process slows down. The buoyant continental part of the Eurasian plate resists being subducted while the previously subducted oceanic part continues to pull downward leading to steepening of the slab and eventually to necking of the plate and the beginning of separation of the upper, lighter crust from the heavier, underlying lithospheric mantle.
Post-collisional evolution I. A decisive moment takes place 30 million years ago when the oceanic part of the subducted plate breaks away. This reduces its tremendous weight. It relaxes like a leaf spring and retracts. This enhances the lifting effect on the mountains, causing them to rise almost to their present height. At the same time, however, the continuing separation of the Eurasian continental crust from its mantle lithosphere allows the latter to further sink into the mantle.
Post-collisional evolution II. Subduction of the mantle lithosphere of the Eurasian plate continues, albeit at a slower rate and controlled by the rate of detachment of the buoyant crust. By suction forces, the Adriatic plate is pulled further northwards. On the surface, the effects of uplift and erosion balance each other out, meaning that the Alps have remained at about the same height for the last 30 million years.
The entire process as video Credit: Dal Zilio et al, Geophys.Res.Letters, 2020
According to Kissling, the model is an excellent way to simulate the uplifting processes that he and his colleague are postulating. “Our model is dynamic, which gives it a huge advantage,” he says, explaining that previous models took a rather rigid or mechanical approach that did not take into account changes in plate behavior. “All of our previous observations agree with this model,” he says.
The model is based on physical laws. For instance, the Eurasian plate would appear to subduct southwards. In contrast to the normal model of subduction, however, it doesn’t actually move in this direction because the position of the continent remains stable. This forces the subducting lithosphere to retreat northwards, causing the Eurasian plate to exert a suction effect on the relatively small Adriatic plate. Kissling likens the action to a sinking ship. The resulting suction effect is very strong, he explains. Strong enough to draw in the smaller Adriatic microplate so that it collides with the crust of the Eurasian plate. “So, the mechanism that sets the plates in motion is not in fact a pushing effect but a pulling one,” he says, concluding that the driving force behind it is simply the pull of gravity on the subducting plate.
Rethinking seismicity
In addition, the model simulates the occurrence of earthquakes, or seismicity, in the Central Alps, the Swiss Plateau and below the Po Valley. “Our model is the first earthquake simulator for the Swiss Central Alps,” says Dal Zilio.
According to the model, seismic activity below the Alps varies significantly from that below the Swiss Plateau, the Jura Mountains and the Po Valley. It shows that earthquakes occur more frequently and at shallower depths below the Alps; below the Swiss Plateau and the Jura, by contrast, they occur less frequently and at greater depths. Furthermore, the new model explains the extension-dominated seismicity within the mountain range whereas the seismicity in the upper crust beneath the forelands exhibits compression.According to Kissling, the model is an excellent way to simulate the uplifting processes that he and his colleague are postulating. “Our model is dynamic, which gives it a huge advantage,” he says, explaining that previous models took a rather rigid or mechanical approach that did not take into account changes in plate behaviour. “All of our previous observations agree with this model,” he says.
Clusters of seismicity display a broad pattern of different style of faulting, which are consistent with the local tectonic regime. Credit: Dal Zilio et al, Geophys. Res. Letters, 2020
The advantage of this earthquake simulator is that it covers a very long period of time, meaning that it can also simulate very strong earthquakes that occur extremely rarely.
“Current seismic models are based on statistics,” Dal Zilio says, “whereas our model uses geophysical laws and therefore also takes into account earthquakes that occur only once every few hundreds of years.” Current earthquake statistics tend to underestimate such earthquakes. The new simulations therefore improve the assessment of earthquake risk in Switzerland.
Reference: “Slab Rollback Orogeny Model: A Test of Concept” by Luca Dal Zilio, Edi Kissling, Taras Gerya and Ylona van Dinther, 25 August 2020, Geophysical Research Letters.
DOI: 10.1029/2020GL089917
The model was created as part of the AlpArray initiative, which aims to advance understanding of how the Alps formed and of seismic risk in the region. As part of the project, scientists from 11 countries and 36 institutions installed 600 sensors all over the Alps. Together, the participants operate the largest academic seismographic network in the world. AlpArray is supported by the Swiss National Science Foundation.
source: scitechdaily.com

Textbooks and Geoscientists May Be Wrong About How the Alps Were Formed

TOPICS:ETH Zurich Geology Geophysics Popular Tectonic Plates

By ETH ZURICH OCTOBER 3, 2020

Central Alps of Switzerland have been lifted to today’s height. Credit: ETH Zurich

ETH researchers have used a computer model to test a new hypothesis about the formation of the Alps while simulating seismic activity in Switzerland. This will help improve current earthquake risk models.

For a long time, geoscientists have assumed that the Alps were formed when the Adriatic plate from the south collided with the Eurasian plate in the north. According to the textbooks, the Adriatic plate behaved like a bulldozer, thrusting rock material up in front of it into piles that formed the mountains. Supposedly, their weight subsequently pushed the underlying continental plate downwards, resulting in the formation of a sedimentary basin in the north adjacent to the mountains – the Swiss Molasse Plateau. Over time, while the mountains grew higher the basin floor sank deeper and deeper with the rest of the plate.

A few years ago, however, new geophysical and geological data led ETH geophysicist Edi Kissling and Fritz Schlunegger, a sediment specialist from the University of Bern, to express doubts about this theory. In light of the new information, the researchers postulated an alternative mechanism for the formation of the Alps.

Altitude of the Alps has barely changed

Kissling and Schlunegger pointed out that the topography and altitude of the Alps have barely changed over the past 30 million years, and yet the trench at the site of the Swiss Plateau has continued to sink and the basin extended further north. This leads the researchers to believe that the formation of the Central Alps and the sinking of the trench are not connected as previously assumed. They argue that if the Alps and the trench indeed had formed from the impact of two plates pressing together, there would be clear indications that the Alps were steadily growing. That’s because, based on the earlier understanding of how the Alps formed, the collision of the plates, the formation of the trench and the height of the mountain range are all linked. Furthermore, seismicity observed during the past 40 years within the Swiss Alps and their northern foreland clearly documents extension across the mountain ranges rather than the compression expected for the bulldozing Adria model.

The behavior of the Eurasian plate provides a possible new explanation. Since about 60 Ma ago, the former oceanic part of the Eurasian plate sinks beneath the continental Adriatic microplate in the south. By about 30 Ma ago, this process of subduction is so far advanced that all oceanic lithosphere has been consumed and the continental part of the Eurasian plate enters the subduction zone. This denotes the begin of the so-called continent-continent collision with the Adriatic microplate and the European upper, lighter crust separates from the heavier, underlying lithospheric mantle. Because it weighs less, the Earth’s crust surges upwards, literally creating the Alps for the first time around 30 Ma ago. While this is happening, the lithospheric mantle sinks further into the Earth’s mantle, thus pulling the adjacent part of the plate downwards.

This theory is plausible because the Alps are mainly made up of gneiss and granite and their sedimentary cover rocks like limestone. These crustal rocks are significantly lighter than the Earth’s mantle – into which the lower layer of the plate, the lithospheric mantle, plunges after the detachment of the two layers that form the continental plate. “In turn, this creates strong upward forces that lift the Alps out of the ground,” Kissling explains. “It was these upward forces that caused the Alps to form, not the bulldozer effect as a result of two continental plates colliding,” he says.

New model confirms lift hypothesis

To investigate the lift hypothesis, Luca Dal Zilio, former doctoral student in ETH geophysics professor Taras Gerya’s group, has now teamed up with Kissling and other ETH researchers to develop a new model. Dal Zilio used ETH’s Euler mainframe to simulate the subduction zone under the Alps: the plate tectonic processes, which took place over millions of years, and the associated earthquakes.

“The big challenge with this model was bridging the time scales. It takes into account lightning-fast shifts that manifest themselves in the form of earthquakes, as well as deformations of the crust and lithospheric mantle over thousands of years,” says Dal Zilio, lead author of the study recently published in the journal Geophysical Review Letters.

Five important stages in the orogeny:

Thirty-seven million years ago, subduction of the heavier oceanic part of the Eurasian Plate (from the left) under the lighter continental Adriatic Plate (right) in the south is in full swing. A shallow “mountain range” (yellow, striped area) forms above the zone where the plates converge, initially as isolated islands that barely protrude above sea level. Light green area: Earth’s mantle; green band: lithosphere; dark green, narrow band: oceanic crust; pink/ruby red bands: lower crust; grey bands: upper crust.

Over millions of years, the oceanic plate becomes increasingly curved, practically curling in on itself. The Eurasian plate as a whole remains stationary. This causes the subducting plate to start exerting a suction effect on the much smaller Adriatic plate, pulling it northwards (to the left in the diagram).

Continent-Continent Collision. When this process of subduction is so far advanced that the lighter, continental part of the Eurasian plate enters the subduction zone and begins to collide with the Adriatic microplate, the subduction process slows down. The buoyant continental part of the Eurasian plate resists being subducted while the previously subducted oceanic part continues to pull downward leading to steepening of the slab and eventually to necking of the plate and the beginning of separation of the upper, lighter crust from the heavier, underlying lithospheric mantle.

Post-collisional evolution I. A decisive moment takes place 30 million years ago when the oceanic part of the subducted plate breaks away. This reduces its tremendous weight. It relaxes like a leaf spring and retracts. This enhances the lifting effect on the mountains, causing them to rise almost to their present height. At the same time, however, the continuing separation of the Eurasian continental crust from its mantle lithosphere allows the latter to further sink into the mantle.

Post-collisional evolution II. Subduction of the mantle lithosphere of the Eurasian plate continues, albeit at a slower rate and controlled by the rate of detachment of the buoyant crust. By suction forces, the Adriatic plate is pulled further northwards. On the surface, the effects of uplift and erosion balance each other out, meaning that the Alps have remained at about the same height for the last 30 million years.

The entire process as video Credit: Dal Zilio et al, Geophys.Res.Letters, 2020

According to Kissling, the model is an excellent way to simulate the uplifting processes that he and his colleague are postulating. “Our model is dynamic, which gives it a huge advantage,” he says, explaining that previous models took a rather rigid or mechanical approach that did not take into account changes in plate behavior. “All of our previous observations agree with this model,” he says.

The model is based on physical laws. For instance, the Eurasian plate would appear to subduct southwards. In contrast to the normal model of subduction, however, it doesn’t actually move in this direction because the position of the continent remains stable. This forces the subducting lithosphere to retreat northwards, causing the Eurasian plate to exert a suction effect on the relatively small Adriatic plate. Kissling likens the action to a sinking ship. The resulting suction effect is very strong, he explains. Strong enough to draw in the smaller Adriatic microplate so that it collides with the crust of the Eurasian plate. “So, the mechanism that sets the plates in motion is not in fact a pushing effect but a pulling one,” he says, concluding that the driving force behind it is simply the pull of gravity on the subducting plate.

Rethinking seismicity

In addition, the model simulates the occurrence of earthquakes, or seismicity, in the Central Alps, the Swiss Plateau and below the Po Valley. “Our model is the first earthquake simulator for the Swiss Central Alps,” says Dal Zilio.

According to the model, seismic activity below the Alps varies significantly from that below the Swiss Plateau, the Jura Mountains and the Po Valley. It shows that earthquakes occur more frequently and at shallower depths below the Alps; below the Swiss Plateau and the Jura, by contrast, they occur less frequently and at greater depths. Furthermore, the new model explains the extension-dominated seismicity within the mountain range whereas the seismicity in the upper crust beneath the forelands exhibits compression.According to Kissling, the model is an excellent way to simulate the uplifting processes that he and his colleague are postulating. “Our model is dynamic, which gives it a huge advantage,” he says, explaining that previous models took a rather rigid or mechanical approach that did not take into account changes in plate behaviour. “All of our previous observations agree with this model,” he says.

Clusters of seismicity display a broad pattern of different style of faulting, which are consistent with the local tectonic regime. Credit: Dal Zilio et al, Geophys. Res. Letters, 2020

The advantage of this earthquake simulator is that it covers a very long period of time, meaning that it can also simulate very strong earthquakes that occur extremely rarely.

“Current seismic models are based on statistics,” Dal Zilio says, “whereas our model uses geophysical laws and therefore also takes into account earthquakes that occur only once every few hundreds of years.” Current earthquake statistics tend to underestimate such earthquakes. The new simulations therefore improve the assessment of earthquake risk in Switzerland.

Reference: “Slab Rollback Orogeny Model: A Test of Concept” by Luca Dal Zilio, Edi Kissling, Taras Gerya and Ylona van Dinther, 25 August 2020, Geophysical Research Letters.
DOI: 10.1029/2020GL089917

The model was created as part of the AlpArray initiative, which aims to advance understanding of how the Alps formed and of seismic risk in the region. As part of the project, scientists from 11 countries and 36 institutions installed 600 sensors all over the Alps. Together, the participants operate the largest academic seismographic network in the world. AlpArray is supported by the Swiss National Science Foundation.

source: scitechdaily.com

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Regards, Dan, a. k. a. smAshomAsh

#9 · October 25, 2020, 10:43 am

New list from south shetland island similar to 12 12 1982, grabbing large quakes two months prior and after here's the list

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#10 · October 25, 2020, 10:43 am

List 2

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Earthquake Studies...

New research reveals how water in the deep Earth triggers earthquakes and tsunamis