English: Mare Spumans, meaning the "foaming sea", is located just south of Mare Undarum on the near side. It is one of the many elevated lakes contained in the Crisium basin, surrounding Mare Crisium. The surrounding basin material is of the Nectarian epoch, while the mare basalt being of the Upper Imbrian epoch. A part of Mare Undarum can be seen at the top of the photo. The crater Dubyago can be seen at the top right of the photo as the circular feature with a white ring around it. You can clearly make out the crater Apollonius W on the western rim of the mare. The crater is white with a well defined ray system surrounding.