Another Earthquake Linked to Aftermath of Hydrogen Bomb Test in North Korea

25 Aug 2010 – “Storax Sedan” underground nuclear test – July 1962
Storax Sedan (yield 104 kt) – shallow underground nuclear test conducted by the United States on 6 July 1962 at Nevada Test Site. The main purpose of the detonation was to asses the non military dimension of a nuclear explosion. Image in the public domain

Photo: The Official CTBTO Photostream

SEOUL, Feb. 6 (Yonhap) — A 2.6-magnitude earthquake shook North Korea’s northern area on Tuesday in the aftermath of the communist country’s latest nuclear test, in September last year, the South Korean weather agency said.

The quake took place at 7:53 p.m., 46 kilometers northwest of Kilju, North Hamgyong Province, where North Korea has conducted a total of six nuclear tests, including the latest one in September last year, according to the Korea Meteorological Administration (KMA).

The depth of the tremor’s epicenter appeared to be 5 km and it is believed to have been a natural result of the sixth nuclear test, in September, the agency said.

North Korea claimed to have tested a hydrogen bomb in the Sept. 3 nuclear detonation, the most powerful of the nuclear tests the North has conducted.

The weather agency detected an artificial quake with a 5.7 magnitude at the nuclear site in the northeast area at the time of the sixth nuclear test.

The Tuesday quake occurred some 3km northeast of North Korea’s sixth nuclear test site, a KMA official said.

It was the eighth natural quake that has taken place in North Korea since the September nuclear test.

Chronology of North Korea’s missile, rocket launches

Photo Courtesy Yonhap News Agency.

2017/11/29

SEOUL, Nov. 29 (Yonhap) — North Korea fired what appears to be a long-range ballistic missile on Wednesday. The following is a chronology of the North’s major missile provocations.

— Aug. 31, 1998: North Korea fires off its first ballistic missile, the Unha-1, also known as the Taepodong-1, from the launch site of Musudan-ri in North Hamgyong Province.

— July 5, 2006: North Korea test-fires an advanced version of the Taepodong-2 missile at the Musudan-ri launch site.

— April 5, 2009: North Korea launches the Unha-2 rocket at the Musudan-ri launch site with the attendance of leader Kim Jong-il and his son, Kim Jong-un.

— April 13, 2012: North Korea fires off a long-range rocket, the Unha-3, from the Dongchang-ri launch site in North Pyongan Province. But the rocket crashes in pieces into the sea shortly after takeoff.

— Dec. 1, 2012: North Korea says it will launch a working satellite, the Kwangmyongsong-3, on the carrier rocket Unha-3, between Dec. 10 and 22.

— Dec. 10, 2012: North Korea extends the rocket launch window until Dec. 29, citing technical problems in the first-stage control engine module.

— Dec. 12, 2012: North Korea launches a long-range rocket from the Dongchang-ri launch site in North Pyongan Province.

— May 8, 2015: North Korea for the first time tests a submarine-launched ballistic missile (SLBM), dubbed KN-11. Seoul said that it was more of a test for the ejection rather than firing.

— Nov. 28, 2015: North Korea fires off an SLBM in the East Sea, but Seoul views the test as a failure.

— Dec. 21, 2015: South Korea’s military says North Korea conducted another SLBM test in December, but the test ended in failure. The Washington Free Beacon reported that North Korea succeeded in the underwater test of a KN-11 missile near the eastern port of Sinpo on Dec. 21, citing unidentified U.S. defense officials.

— Feb. 2, 2016: North Korea notifies U.N. agencies of its plan to launch a satellite between Feb. 8 and 25.

— Feb. 6, 2016: North Korea informs the International Maritime Organization of its plan to move up the launch date to Feb. 7-14.

— Feb. 7, 2016: North Korea fires a long-range rocket from the Dongchang-ri launch site at around 9:30 a.m. The North claims it has successfully placed a satellite, named Kwangmyongsong-4, into orbit.

— March 18, 2016: North Korea launches what appears to be two mid-range Rodong ballistic missiles from its western province.

— April 15, 2016: North Korea conducts its first test-launch of an intermediate-range Musudan ballistic missile, also known as the BM-25, but the launch ends in failure.

— April 23, 2016: North Korea test-fires an SLBM in the East Sea, which flies only about 30 km

— April 28, 2016: North Korea launches two intermediate-range Musudan ballistic missiles, but the launches end in failure.

— May 31, 2016: North Korea test-fires an intermediate-range Musudan, but the launch ends in failure.

— June 22, 2016: North Korea fires off two intermediate-range Musudan missiles. One missile flies about 400 km, which experts widely view as a success.

— July 9, 2016: North Korea launches an SLBM off its east coast, but Seoul says the missile appears to have exploded at an altitude of some 10 kilometers.

— July 19, 2016: North Korea test-fires two mid-range Rodong missiles and a shorter-range Scud missile.

— Aug. 3, 2016: North Korea fires off two mid-range Rodong ballistic missiles from near the southwestern area. One missile flies about 1,000 km before falling into Japan’s exclusive economic zone (EEZ).

— Aug. 24, 2016: North Korea test-fires an SLBM in waters off its east coast towards Japan. The missile flies about 500 km, making it the longest flight by such a missile.

— Oct. 15, 2016: North Korea fires off an intermediate-range Musudan ballistic missile, but it explodes after launch.

— Oct. 20, 2016: North Korea launches what appears to be an intermediate-range Musudan, but the test ends in failure.

— Feb. 12, 2017: North Korea launches a new intermediate-range ballistic missile, Pukguksong-2, into the East Sea. Experts say the country appears to apply technology used in the SLBM to have developed a new missile.

— March 6, 2017: North Korea fires four ballistic missiles from its the Dongchang-ri launch site toward the East Sea.

— March 22, 2017: North Korea launches a missile from its east coast that is presumed to have failed. The type of the missile is not confirmed.

— April 5, 2017: North Korea fires what appears to be a type of KN-15 intermediate-range ballistic missile.

— May 14, 2017: North Korea fires a new mid-to-long-range ballistic missile, the Hwasong-12, from a northwest site. It flies about 700 km before landing in the East Sea.

— May 21, 2017: North Korea fires the ground-to-ground Pukguksong-2 missile, also known as a KN-15. It flies more than 500 km.

— May 27, 2017: North Korea is presumed to have launched a surface-to-air guided missile, believed to be a KN-06, from the eastern region.

— May 29, 2017: North Korea fires what is presumed to be a Scud-type ballistic missile. It flies about 450 km.

— June 8, 2017: North Korea test-fires multiple surface-to-ship cruise missiles.

— July 4, 2017: North Korea launches a ballistic missile from a northwestern province into waters off its east coast. Pyongyang claims that it successfully test-fired an intercontinental ballistic missile and that it reached an altitude of 2,802 kilometers and flew 933 km.

— July 28, 2017: North Korea launches a ballistic missile from the northern province of Jagang into the East Sea.

— Aug. 26, 2017: North Korea fires three short-range ballistic missiles into the East Sea.

— Aug. 29, 2017: North Korea launches a ballistic missile over Japan from a region near Pyongyang. It flies more than 2,700 kmat a maximum altitude of around 550 km.

— Sept. 15, 2017: North Korea fires a ballistic missile over Japan from Pyongyang. It reaches as high as some 770 km and flies around 3,700 km. It marked the first missile launch after the U.N. Security Council implemented fresh sanctions over its sixth nuclear test.

— Nov. 29, 2017: North Korea launches what appears to be an intercontinental ballistic missile (ICBM). It flies some 960 km, reaching an apogee of around 4,500 km.

North Korea Seismic Data in Comparison with Previous Tests

The seismological observatory NORSAR at Kjeller, Norway, has detected the latest underground nuclear test by North Korea.

NORSAR has recorded signals from an underground nuclear test explosion conducted by North Korea at its Punggye-ri test site on 3 September 2017. NORSAR has estimated the explosive yield at 120 kilotons TNT, based on a seismic magnitude of 5.8.In comparison, the explosive yield of the nuclear bomb dropped on Hiroshima on 6 August 1945 was estimated at 15 kilotons TNT, while the bomb dropped on Nagasaki three days later was 20 kilotons TNT.

The figure above shows at the bottom the seismic recording of the latest test in North Korea made at NORSAR’s station in Hedmark, Norway. The five upper traces show recordings at the same station for the five preceding tests, conducted by North Korea in 2006, 2009, 2013 and 2016 (two explosions in 2016). Today’s test is as can be seen from this figure clearly the strongest so far.

The test site in North Korea is located at a distance of 7360 km from NORSAR’s seismic station in Hedmark. Given that the seismic waves take approximately 11 minutes to propagate from North Korea to Norway, the measurements indicate that this explosion took place at 03:30 UTC.

The figure below shows the estimated locations within the Pungggye-ri test site of the five previous tests (red dots). The tests are conducted in the tunnel system inside the mountain. The area of the likely location of the most recent test is indicated in the figure. Some additional work is required in order to estimate a precise location.

North Korea claims that this was a test of a hydrogen bomb; the same claim was made for previous tests. It is not possible from the seismic data alone to determine if this was a test of a hydrogen bomb, but we can say in general that the credibility of the claim increases with increasing explosive yield. Possible leakage of radionuclides may be registered later and may indicate the type of bomb. These data may be available in a matter of weeks, if there is a leakage from the test site.

TYPES OF NUCLEAR WEAPONS TESTS

Nuclear explosions have been detonated in all environments: above ground, underground and underwater. Bombs have been detonated on top of towers, onboard barges, suspended from balloons, on the earth’s surface, underwater to depths of 600m, underground to depths of more than 2,400m and in horizontal tunnels. Test bombs have been dropped by aircraft and fired by rockets to altitudes of over 500 kilometres.

Atmospheric testing

Atmospheric testing refers to explosions which take place in the atmosphere.

All told, of the over 2,000 nuclear explosions detonated worldwide between 16 July 1945 (United States) and 29 July 1996 (China), 25 % or over 500 bombs were exploded in the atmosphere: over 200 by the United States, over 200 by the Soviet Union, about 20 by Britain, about 50 by France and over 20 by China.

International concern over radioactive fallout resulting from atmospheric tests escalated in the mid 1950s. In March 1954, the United States tested its hydrogen bomb Castle Bravo in the Pacific’s Marshall Islands. The Bravo test created the worst radiological disaster in the United States’ testing history. By accident, local civilians on the Marshall Islands, U.S. servicemen stationed on Rongerik atoll, and the Japanese fishing trawler Lucky Dragon, were contaminated with the fallout.

Nuclear weapon tests have been carried out in all environments: above ground, underground and underwater.

: Signing of the Partial Test Ban Treaty, 5 August 1963. Secretary of State Dean Rusk signing for the United States; Foreign Minister Andre Gromyko, signing for the Soviet Union; and Lord Hume signing for the United Kingdom.

Atmospheric testing was banned by the 1963 Partial Test Ban Treaty. Negotiations had largely responded to the international community’s grave concern over the radioactive fallout resulting from atmospheric tests. The United States, the Soviet Union and the United Kingdom became Parties to the Treaty; France and China did not. France conducted its last atmospheric test in 1974, China in 1980.

CTBTO’s infrasound IMS stations are used to detect nuclear explosions by monitoring low-frequency sound waves in the atmosphere. CTBTO Radionuclide IMS stations are designed to detect radioactive particles emanating from an atmospheric test.

High-altitude nuclear testing

: Artificial aurora over Honolulu created by the 1962 Starfish Prime test.

Around 20 nuclear tests were conducted by the United States and the Soviet Union in high altitudes or lower outer space between 1958 and 1962. The main aim of these explosions, detonated at heights between 40 and 540 kilometres, was to determine the feasibility of nuclear weapons as anti-ballistic missile defense or anti-satellite weapons. The largest such test, the 1.4 megaton U.S. Starfish Prime test in 1962, damaged and destroyed several of the satellites in orbit at the time and led to wide-spread power outages on the ground. High-altitude or outer space nuclear testing is equally banned by the 1963 Partial Test Ban Treaty as well as by the 1967 Outer Space Treaty.

Underwater testing

Underwater testing refers to explosions which take place underwater or close to the surface of the water. Relatively few underwater tests have been conducted. The first underwater nuclear test – ‘Baker’ (video) – was conducted by the United States in 1946 at its Pacific Proving Grounds in the Marshall Islands with the purpose of evaluating the effects of nuclear weapons used against naval vessels. Later, in 1955, the United States’ Operation Wigwam conducted a single underwater nuclear test at a depth of 600 m to determine the vulnerability of submarines to nuclear explosions.

Underwater nuclear explosions close to the surface can disperse large amounts of radioactive water and steam, contaminating nearby ships, structures and individuals.

Underwater nuclear testing was banned by the 1963 Partial Test Ban Treaty. The CTBTO’s hydroacoustic IMS stations are those best suited to detect nuclear explosions underwater.

Of the over 2,000 nuclear explosions detonated worldwide between 1945 and 1996, 25 % or over 500 bombs were exploded in the atmosphere.

Underground testing

Underground testing means that nuclear explosions are detonated at varying depths under the surface of the earth. These comprised the majority (i.e. about 75%) of all nuclear explosions detonated during the Cold War (1945–1989); that is, over 800 of all tests conducted by the United States and nearly 500 of all tests conducted by the Soviet Union.

When the explosion is fully contained, underground nuclear testing emits negligible fallout compared to atmospheric testing. However, if underground nuclear tests “vent” to the surface, they can produce considerable radioactive debris. Underground testing is usually evident through seismic activity related to the yield of the nuclear device.

Underground nuclear testing was banned by the 1996 Comprehensive Nuclear-Test-Ban Treaty (CTBT) that bans all nuclear explosions anywhere, by anyone.

75 % of all nuclear explosions have been conducted underground.

: Radionuclide station 56, Peleduy, Russian Federation

The CTBTO’s seismic IMS stations are used to detect nuclear explosions underground. The seismic data is combined with radionuclide data. Only the radionuclide technology can determine if an explosion is nuclear in origin; its stations and laboratories around the world monitor the presence of particulates and/or noble gases in the atmosphere.

https://www.ctbto.org/nuclear-testing/history-of-nuclear-testing/types-of-nuclear-weapons-tests/

COURTESY CTBTO

The Comprehensive Nuclear-Test-Ban Treaty (CTBT) bans nuclear explosions by everyone, everywhere: on the Earth’s surface, in the atmosphere, underwater and underground.

Why is the CTBT important?
It makes it very difficult for countries to develop nuclear bombs for the first time, or for countries that already have them, to make more powerful bombs. It also prevents the huge damage caused by radioactivity from nuclear explosions to humans, animals and plants.

CTBTO EXECUTIVE SECRETARY LASSINA ZERBO ON THE UNUSUAL SEISMIC EVENT DETECTED IN THE DEMOCRATIC PEOPLE’S REPUBLIC OF KOREA

Vienna, 3 September 2017

“Our monitoring stations picked up an unusual seismic event in the Democratic People’s Republic of Korea (DPRK) today at 03:30 (UTC). So far over 100 of our stations are contributing to the analysis. The event seems to have been larger than the one our system recorded in September last year and the location is very similar to that event. Our initial location estimate shows that the event took place in the area of the DPRK’s nuclear test site. ( 03-SEP-2017 03:30:06 LAT=41.3 LON=129.1 )

Our experts are now analysing the event to establish more about its nature and we are preparing to brief our Member States today in Vienna.

“If confirmed as a nuclear test, this act would indicate that the DPRK’s nuclear programme is advancing rapidly. It constitutes yet another breach of the universally accepted norm against nuclear testing; a norm that has been respected by all countries but one since 1996. It also underlines yet again the urgent need for the international community to act on putting in place a legally binding ban on nuclear testing once and for all. I urge the DPRK to refrain from further nuclear testing and to join the 183 States Signatories who have signed the Comprehensive Nuclear-Test-Ban Treaty (CTBT). I sincerely hope that this will serve as the final wake-up call to the international community to outlaw all nuclear testing by bringing the CTBT into force,” said Lassina Zerbo, Executive Secretary of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO).

Broadcast quality footage will be posted in the CTBTO Newsroom as it becomes available.

Background

The CTBT bans all nuclear explosions. The Treaty will enter into force once signed and ratified by the remaining eight nuclear technology holder countries: China, Egypt, the DPRK, India, Iran, Israel, Pakistan, and the United States.

A verification regime is being built to monitor compliance with the Treaty. Nearly 90 percent of the 337 facilities of the International Monitoring System (IMS) are already in place; see interactive map. The system swiftly, reliably and precisely detected all five DPRK’s declared nuclear tests. After the DPRK announced nuclear test on 12 February 2013, the CTBTO was the only organization to detect radioactivity attributable to the event.

CTBTO Member States are provided with data collected by the monitoring stations, as well as data analyses prepared by the International Data Centre in Vienna, Austria. Once the Treaty has entered into force, an on-site inspection can be invoked in case of a suspicious event.

What is the CTBT?

The Comprehensive Nuclear-Test-Ban Treaty (CTBT) bans nuclear explosions by everyone, everywhere: on the Earth’s surface, in the atmosphere, underwater and underground.