Oregon L5 Society |Lavatube Entrance Amelioration on the Moon
and Mars| Robert D. McGown , Cheryl Lynn York, Thomas L.
Billings, Bryce Walden (Copyright © 2002 by the American Society
of Civil Engineers) To explore and utilize lavatube caverns, a
negotiable entrance is vital. Lavatube entrance amelioration
includes clearing debris, establishing a transportation right-
of-way, and preparing for and installing various access aids.
There are four main types of entrances to lavatube caves: a
"rille entrance," a "skylight," a "hornito," and an engineered,
artificial skylight. A rille entrance should be easiest to
improve. In rare cases it may be possible to simply walk or
drive into the lavatube. More likely, the rille entrance will be
choked by initial rille collapse and eons of weathering. A
mucker and cable assembly used to clear the entrance might
become a cablecar. Later, a suspended road may be built. A
skylight forms when a small portion of the cave ceiling
collapses. The skylight entrance is prone to furthe