Table T3. General terminology for basaltic lavas and their explanations.
Terminology
Explanation
Lava flow field A body of lava identified on the basis of field relations and chemistry as the product of one eruption. It may consist of several lava flows.
Lava flow A regional subunit formed as a continuous event and may correspond to a single eruption episode. A flow may consist of many flow lobes.
Flow lobe A single unit of lava that is surrounded by a chilled crust and can vary in size from tens of centimeters to several kilometers. This definition applies to both subaerial and subaqueous lavas.
Sheet lobe A lobe with flat or gently undulating flow surfaces and is produced by one continuous outpouring of lava. It is much wider than it is thick and can be tens to thousands of meters wide.
Breakout A small lobe originating as an outbreak of lava from the molten interior of a previously formed lobe. Lobe margin and surface breakouts refer to lobes formed as breakouts through the front (or sides) and the upper surface of the feeding lobe, respectively.