Chasma
A chasma ( Greek χάσμα chásma "crevice, throat") is a deep crevice or a torn canyon delimited by steep rock walls . The crevice can be open, but it can also be partially closed by sediments or landslides .
The plural of the Chasma is the Chasmata . The word casemate is also derived from chasma .
While the word is rarely used in terrestrial geology , it is a common part of the name in planetary nomenclature for large rift valleys on Mars and Venus , as well as on some large moons . Some examples:
- Artemis Chasma (Venus)
- Chasma Boreale (Mars)
- Ganges Chasma (Mars)
- Hebes Chasma (Mars)
- Ithaca Chasma (Saturn's Moon Tethys )