The source of water
Occasionally it rains in the desert, and there is often a storm. The Sahara Desert had a record of 44 mm of precipitation within 3 hours. At this time, the normally dry river will be filled with water quickly and it is easy to flood. Although there is less rain inside the desert, the desert often enters the river from the nearby mountains. These rivers usually carry a lot of soil, and they have been working in the desert for a day or two. If there is enough water, a seasonal lake will form in the desert, which is generally shallower and salty. Because the bottom of the lake is very flat, the wind will blow the lake to dozens of square kilometers. After the small lake has dried up, it will leave a salt flat. There are hundreds of such salt flats in the United States, mostly are the relics during the Ice Age 12,000 years ago, the most famous of which is the Great Salt Lake in Utah.
Some minerals form in the dry religions. The water on the ground dissolves the minerals and then concentrates it near the surface of the groundwater, making it an easy-to-develop reservoir. There are many minerals on the salt flats that remain on the surface after evaporation. The world’s largest oil reserves are mostly in the desert, but these storages are not due to the dry climate. Before these areas became deserts, they were shallow seas, and oil was formed by submarine plants.