This slide and slide 28 illustrate the diversity of size and morphology of the volcano-tectonic structures known as coronae. A typical corona consists of an inner circular plateau; a ridged, raised rim; and an annular trough. Volcanic features in the interior are common. The median diameter for coronae is ~250 kilometers, and the diameters of over two-thirds of the coronae are within 150 kilometers of the median.
This slide shows two of the largest coronae, Heng-O (2°N, 355°E) and Ceres (16°S, 151.5°E).