VOLCANIC VENTS


Center latitude: 26.95°N; longitude: 301.0°E
Scale: The depression to the left is 9.5 km (5.9 mi.) wide
On the left side of the image, the large depression is thought to be a volcanic vent that formed inside the peak-ring basin Praxiteles. On the right are hollows.

Center latitude: 26.70°N; longitude: 299.3°E
Scale: Praxiteles crater has a diameter of 182 kilometers (113 miles).

Center latitude: 35.84°N; longitude: 64.00°E
Scale: The vent is approximately 36 km (22 miles) across
The volcanic vent northeast of Rachmaninoff basin is framed perfectly in this image.

Whereas on Earth volcanoes frequently form mountains, on Mercury most of the volcanic landforms that have been identified are irregularly-shaped pits or depressions that are on the order of a few tens of kilometers in size. These vents were the sites of explosive volcanic eruptions. The magma and rocks ejected in an explosive eruption are called pyroclastic materials, and can form a deposit surrounding the vent. In enhanced-color images, Mercury's volcanic vents and their surrounding pyroclastic deposits appear reddish-orange or yellow (center image). A volcanic vent northeast of Rachmaninoff basin is framed perfectly in the far right image. The area surrounding the vent appears smooth due to a blanket of fine particles that were ejected explosively in a pyroclastic eruption. This vent is deeper than Earth's Grand Canyon.

Learn more about volcanic vents on Mercury!