For eight month in 1783-84, the Laki volcanic fissure system
in Iceland spewed over 100 million tons of sulphur dioxide into the atmosphere.
The first one follows the fissure system
of WNW-ESE direction and is situated approximately up-right to the slope.
Before sealing, each fissure system
was cleaned of any plaque residue by bristle brush and prophylactic paste.
The images showed geological evidence of catastrophic floods caused by volcanic activity in a fissure system
called the Cerberus Fossae.
This test showed that use of etch and Prime and Bond[R] was significantly more likely to result in placement of a FS which remained covering more of the pit and fissure system
over a 12 month period than use of Xeno[R] III for enamel preparation.
Most significant is the fissure system
of complementary directions NNE-SSW and ESE-WNW, which also shapes outer form of the Brana outcrop (Fig.