A project to dig up to the mantle inside the Earth is finally started using the Deep Earth Exploration Vessel "CHIKYU"

World's first riser-type science drilling vesselCHIKYU"Inside the earth"MantleIn order to dig deep into the ocean floor, preliminary survey will be conducted in September 2017. Human beings are expected to acquire the rocks of the mantle inside the Earth that are said to have value comparable to that of the moon rocks Apollo 11 brought back.

Japan-led research group preparing to drill down to the mantle - The Japan News
http://the-japan-news.com/news/article/0003619423

Mantoru Project
http://www.jamstec.go.jp/ods/j/mantle/

Japanese scientists want to be first to drill into the Earth's mantle - CNN.com
http://edition.cnn.com/2017/04/07/asia/japan-drill-mantle/index.html

The inner layer "Earth mantle" between the crust and the nucleus (core) occupies about 80% of the earth's volume and is a perfect material to know the process of the birth of the earth from hardness and moisture content, but deep inside the Earth There are no people who have gotten it yet. In order to reach the mantle, it is necessary to dig deep the ground deeply, but because the thickness of the crust is thinner in the sea than in the ground, digging in the sea has a low technical hurdle and deep sea drilling boats to dig the ocean floor Is used.


Even though the crust is thin, the thickness of the crust is at least 6 kilometers, and this is done in the mantle mining project by drilling with a metal drill mounted on a drilling vessel. The project aiming to reach the mantle started in the late 1950s as an American "Mohol plan", but it was torn down due to technical and monetary problems. The Mohol plan is led by Japan Marine Science and Technology Agency (JAMSTEC)Ocean Drilling Science Research and Development Center (ODS)"Mohuru Project", a mantle drilling project by the exploration vessel "Chikyu", was launched. Finally, in September 2017 we reached the stage to undertake a preliminary investigation off Hawaii.


The candidate has been narrowed down to 3 points in the Pacific Ocean off Hawaii, off Costa Rica and off Mexico at the seabed which we are already digging. In the ocean floor below 4000 meters deep, you will pick out places with the highest possibility of reaching the mantle.


According to ODS, three large walls of 'deep water area', 'hard rock' and 'heat' will stand up before reaching the mantle. The rock under the ocean floor is very hard, so the drill blade wears quickly, so frequent replacement is required, and since the top of the mantle is expected to be hotter than 200 degrees, the drill Development is required. We have already succeeded in developing a light and durable pipe that already contains a drill that digs the ocean floor, and the international project team thinks that it is technically possible to drill.


Since the exploration vessel "CHIKYU" boasts more than three times the drilling capacity of conventional vessels, it is expected to achieve success in reaching the first mantle of the human race. First of all, in mid September 2017 a survey was conducted in JAMSTEC's deep-sea survey vessel "KAIREI" for about two weeks in the northeast of Hawaii, and we will use the acoustic waves to observe the thickness and temperature of the crust. After that, drilling will be started in the early 2020s as the mantle reaching project by the deep Earth exploration vessel "CHIKYU".