Surface Processes

Planet Trek:

Mapping New Worlds

Part II: Concept Introduction: Features

Activity #3 - Surface Processes

The surfaces of all terrestrial worlds are shaped by four essential processes:

volcanism - caused by molten lava or other liquid from the interrior erupting on the surface
impact craters - caused by an impact on the surface from rocks or other material
erosion/volatiles - caused by weathering (water or wind) or vaporization of the surface
tectonics - caused by folding and faulting forces which deform the surface

Listed below are definitions of the 11 types of surface features you identified in Activity 2, along with 12 other features from the USGS Descriptor of Terms.

Surface Feature	Description
Catena	Chain of craters
Chasma	Deep, elongated, steep-sided depression
Craters	Circular depression
Dorsum	Ridge
Ejecta	Rays of debris from an impact crater
Fluctus	Flow terrain
Fossae	Long, narrow, shallow depression
Labes	Landslide
Lacus	"Lake" - small plain
Lenticula	Small dark spots on Europa
Mare or Maria	"Sea" - large circular plain
Mensae	Flat-topped prominence with cliff-like edges
Mons	Mountains
Reticula	Reticular or netlike pattern on Venus
Rima or Rimae	Fissure
Rupes	Scarp (cliffs produced by faulting or erosion)
Sinus	"Bay" - small plain
Sulcus or Sulci	Subparallel furrows and ridges
Tessera or Tesserae	Tile-like, polygonal terrain
Tholus or Tholi	Small, domical mountain or hill
Undae	Dunes
Vallis or Valles	Valley
Volcano	Mons (mountains) that erupted

Using the description for these terms, decide which type of surface process created each one. List each of the terms in the correct category below to complete the table. Please note that some of these may fit into more than one process!

Volcanism	Impact Craters

Erosion/Volatiles	Tectonics

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