Peter Kelemen believes that these decomposing rocks could help humans solve an important problem: climate change. The water leaves a frosty coating of calcite crystals as it flows over the rock. The calcium quickly reacts with CO 2 in the air, forming films of calcium carbonate (calcite) that can appear within 24 hours. At these alkaline springs in Oman, water emerges from the ground saturated with dissolved calcium. Like slow but powerful fingers, the minerals widen the cracks, prying the rock apart. These jagged veins of black, white and blue-green stone push ever deeper into the bedrock. The water and gases react with the rock to form new, colorful minerals. When rain falls, it trickles into cracks in the rock, carrying gases from the air.

Now exposed to air and water on Earth’s surface, these minerals prove chemically unstable. They formed dozens of kilometers (miles) below - deeper than humans have ever delved in search of oil or gold.

Here, in the desert nation of Oman, east of Saudi Arabia, the mountains comprise exotic minerals that don’t normally exist at Earth’s surface. Only a few types of plants can grow in such alien soils. This water leaves a carpet of frosty white crystals as it flows over the ground. Water from natural springs is often saturated with minerals. Flammable hydrogen gas sometimes bubbles from groundwater. The tired, crumbling peaks of the Al Hajar Mountains are slowly decomposing like a slab of rotten meat.

Under stone over sea