New Zealand and Japanese scientists say a joint exploration of deep waters in the Pacific Ocean could yield strategic mineral deposits and new forms of life. Scientists from a number of research organizations joined their Japanese counterparts on the Japanese research vessel Yokosuka in Tonga in the southwest Pacific this week, Chinese news agency Xinhua reported. Together they will explore ecosystems in underwater mountains and volcanoes around 600 miles northeast of New Zealand using an advanced deep sea submersible capable of diving to 4 miles beneath the ocean surface, researcher leaders said. \"You never know what to expect in the deep sea, animal life on the seamounts could be sparse, or there could be rich diversity and abundant new communities,\" Malcolm Clark of New Zealand\'s National Institute for Water and Atmospheric Research said in a statement. The other focus of the expedition would be dives to hydrothermal systems (seafloor hot springs) to sample the hot water being discharged from vents on the seafloor together with any mineralization and animals, researchers said.