On January 14, a massive eruption of submarine volcanoes in the South Pacific island nation of Tonga had a huge impact on the region and triggered a strong tsunami that affected Pacific rim countries such as Australia, New Zealand, Japan and the United States. For a time, the animated pictures and videos of the volcanic eruption brushed the circle of friends, and everyone intuitively felt a "roar" of the earth. As the undersea volcanic eruption in Tonga continues to ferment, many citizens also have concerns and concerns. What impact will this eruption have on us? Will there be changes to the future climate? On January 18, the reporter contacted experts in relevant majors of Qingdao's many universities in Qingdao to bring the relevant follow-up to the volcanic eruption.
There are many extinct volcanoes around Qingdao
Many old Qingdao know that in Qingdao, there is a volcanic island, where the scenery is beautiful, and it is still a good place to fish in the sea. That's right, Bamboo Fork Island. Zhucha Island is a volcanic island, and there is still a relatively complete volcanic crater on the island. Similar to Zhucha Island, Lingshan Island and Saitang Island also have a common feature, the island is surrounded by volcanic rock, just like pouring down from the sky, deformed and different, looking crisp, hard texture.
Wang Taitung Stone Ancient Volcano
"The West Coast Wangtai Dongshi Scenic Area, the Jimoma Mountain Geopark, and some islands near Jiaozhou Bay all have ancient volcanoes, and some of them still retain intact craters." Ni Jinlong, an associate professor at the School of Earth Sciences and Engineering of Shandong University of Science and Technology, said that these ancient volcanoes (extinct volcanoes) were formed 100 million years ago, and the earth was in the Cretaceous era, which was also a period of dinosaur prosperity. It is understood that 100 million years ago, the earth's crust in North China underwent strong cracking, including Qingdao, Gaomi, Laiyang, Zhucheng and other places, there were strong volcanic eruptions, forming thick volcanic rocks on the surface.
The broad continental shelf weakens tsunami waves
"Will this volcanic eruption in Tonga affect us? "Recently, with the continuous fermentation of the volcanic eruption in Tonga, citizens in coastal cities have raised relevant questions. To this end, Wang Nan, a lecturer at the School of Oceanography and Atmosphere of the Ocean University of China, said: "The tsunami generated by the volcanic eruption in Tonga hit the countries along the Pacific coast, but the continent is far from Tonga in the South Pacific, and the continent has a very wide continental shelf, which can effectively weaken the energy of the tsunami wave, and the wave height of the tsunami wave monitored in the coastal areas of the mainland generally does not exceed 20 cm, so the tsunami caused by the volcanic eruption of Tonga will not bring us a catastrophic impact." ”
Why did the Tonga volcano "thunder" this time? Wang Nan said, "Tonga Volcano is at the junction of the Indo-Australian Plate and the Pacific Plate, and the tonga trench on its east side can reach a maximum depth of 10,882 meters, which belongs to the typical active continental edge island arc volcanic system, and when the Pacific plate subducts under the Indo-Australian Plate in the depths of the trench, the accompanying earthquakes and volcanic activity will occur frequently." In addition, there may be mantle columns and magma chambers in the lower part of the Tonga volcano, which are also the source of material energy for the deep earth where volcanic eruptions may occur. Based on this tectonic environment and the history of periodic eruptions of Tonga volcanoes, the volcano will most likely continue to erupt multiple times, lasting from weeks to months. ”
Although the tsunami caused by the volcanic eruption in Tonga has no catastrophic impact on the mainland, Wang Nan said that continuous volcanic eruptions produce large amounts of volcanic ash and harmful gases, which can block solar radiation or affect atmospheric circulation and produce cooling, and can also produce large amounts of aerosols to cause rainfall. Current volcanic eruptions are still relatively small in relative history and may have a large impact on the local climate of the Southern Hemisphere, with limited impact on the Northern Hemisphere and the global climate. Subsequent international monitoring of the frequency, intensity and duration of eruptions of Tonga volcanoes will continue to be monitored internationally, and whether they can have an impact on the continental or global climate will ultimately be calculated according to the volume of the eruptions.
Qingdao's geological structure environment is stable
"Because the continental coastal zone is not at the boundary of large plates, it is located on the edge of a passive continent, the continental shelf is wide, the plate tectonic movement is relatively stable, and the earthquake mainly comes from the local tectonic movement inside the plate, usually with low frequency and small magnitude." Therefore, there is no such frequent volcanic and seismic activity as Japan and Tonga in the coastal areas of the mainland, and everyone can rest assured. In addition, Wang Nan also said that the state will set the elevation level zero point in Qingdao, but also because the local geological structure environment in Qingdao is stable, and the uplift and decline of the earth's crust are not obvious, which is conducive to the long-term stability of the elevation benchmark.
Ancient volcano of Mt. Muroma
"For a long time, many citizens have misunderstood the 'hot springs' and 'seismic belts'. Ni Jinlong said that there is no necessary connection between "hot springs" and "seismic belts". There are many hot springs in Qingdao Jimo District because Jimo is on the Muping-Jimo fault zone, which extends along Jimo to Muping City in the north of the peninsula, and due to the large depth of the fracture cutting crust, hot water in the deep part of the crust flows out along the fault zone where the surface pressure is low. (Guanhai News/Qingdao Morning Post reporter Zhong Shanglei)