Throughout the national park, you can observe different geomorphological structures of high volcanological interest.
Sea of lava: It constitutes the most characteristic element of the national park and is made up of a large area covered by lava of different types, depending on the viscosity. The most viscous lavas are the so-called "aa". When they cool down, they form a very shrivelled and rough surface on which is very difficult to walk. The more fluid lava flows are the "pahoe-hoe". They have a less rough surface and often present a curved aspect, due to the pressure produced by the streams that are further behind. While they are moving forward, they tend to twist, creating striking ropy lava flows.
Caves: The "pahoe-hoe" lavas create volcanic pipes or caves when the external part of the stream cools down and solidifies quickly, while lava is still flowing in the interior.
Hornitos (little ovens): These structures are secondary eruptive vents through which gases and lava are expelled, without forming a volcanic building of large dimensions. The most characteristic of the park is the Manto de La Virgen.
Cones of Cínder: These are volcanic buildings that were covered by volcanic materials of small size (pyroclastic flows), which correspond to the strombolian phase of the volcano. They don't always have a symmetrical shape, due to the inclination of the eruptive conduit or to the action of the wind, which can cause the accumulation of pyroclastic rocks in a certain direction.
Other aerial materials: In addition to the pyroclastic rocks, volcanoes also expell large quantities of ash to the air. When these start to solidify, they generate small stones that measure between 2 and 20 mm and receive the name of lapillus. In the Canary Islands it is also known as picón or, more particularly in Lanzarote, as rofe . Larger than the pyroclastic flows, the volcanic bombs are lava fragments that solidify in the air while rotating and, during this movement, they acquire a fusiform aspect.
The national park presents certain surface zones in which the temperature is higher than normal, surpassing the 100ºC. These are located in the edges of craters and create the so-called Geothermal Anomalies, from which the most significantare in the Islote de Hilario, in La Casa de Los Camelleros and at the bottom of the crater of Timanfaya.