Before you think this is a mislabeled EarthCache as you read the information below, here is your challenge. Standing 4,207 m (13,802 ft.) above sea level, its peak is the highest point in the state of Hawaii. However, much of the mountain is under water and when measured from its oceanic base, Mauna Kea is over 10,000 m (33,000 ft.) tall and is the tallest mountain on Earth. To qualify for this challenge, your total accumulated elevation for all your finds must equal the altitude of Mauna Kea…not above sea level like the Mount Everest Challenge, but above the seafloor. To help you out, I have included a checker from Project-GC below.
Mauna Kea is a dormant volcano on the island of Hawaii. It is about a million years old, and has thus passed the most active shield stage of life hundreds of thousands of years ago. In its current post-shield state, its lava is more viscous, resulting in a steeper profile. Late volcanism has also given it a much rougher appearance than its neighboring volcanoes; contributing factors include the construction of cinder cones, the decentralization of its rift zones, the glaciation on its peak, and the weathering effects of the prevailing trade winds. Mauna Kea last erupted 6,000 to 4,000 years ago and is now considered dormant.
In Hawaiian mythology, the peaks of the island of Hawaiʻi are sacred. An ancient law allowed only high-ranking aliʻi to visit its peak. Ancient Hawaiians living on the slopes of Mauna Kea relied on its extensive forests for food, and quarried the dense volcano-glacial basalts on its flanks for tool production. When Europeans arrived in the late 18th century, settlers introduced cattle, sheep and game animals, many of which became feral and began to damage the mountain's ecological balance.
With its high elevation, dry environment, and stable airflow, Mauna Kea's summit is one of the best sites in the world for astronomical observation. Since the creation of an access road in 1964, thirteen telescopes funded by eleven countries have been constructed at the summit. The Mauna Kea Observatories are used for scientific research across the electromagnetic spectrum and comprise the largest such facility in the world. Their construction on a landscape considered sacred by Native Hawaiians continues to be a topic of debate.
