dacite

Phase equilibria and pre-eruption P-T-f[O.sub.2]-f[H.sub.2]O conditions of the dacite magma.

Porphyritic andesite to dacite lava flows (Lava Dacttica Apilulco; thickness < 4 m) with planar fracturing subparallel to the surface constitute the main effusive products.

The main volcanic lithologies are predominately rhyolite, dacite and andesite of Eocene to Miocene in age.

Earlier work by Little River GoldFields NL attempted to identify the source of the gold in the Dalmorton goldfields as related to the nearby Dacite occurrences.

No doubt climatological conditions and the right vines matched to the right soil are important, but it is remarkable how well the block location corresponds to a dominant dacite unit lithology.

(2) Tertiary (volcanic rocks such as basalt, rhyolite, dacite, ignimbrite, and ashflow deposits).

Both the lower and upper volcanic assemblages are generally calc-alkaline and include units of basalt, andesite, dacite and rhyolite.

Tarduno picked out the best preserved grains of feldspar and quartz out of 3.5 billion-year-old dacite outcroppings in South Africa.

The mineralisation drilled is hosted within a 200m to 300m thick thrust fault which may be linked to an intensely silica and clay altered, stock-worked and brecciated quartz dacite intrusive complex located around 1,200m to the south.

Along the crest of the anticline, at the contact between the schists and the limestones, a volcanic chimney was emplaced: the chimney, measuring 100 X 200 meters in oval cross-section, consists of a pipe of trachyte or dacite surrounded by an explosion breccia.

The newest is still erupting a thick form of lava known as dacite.

Intrusive domes of hornblende dacite is also found in the southwest flanks of Kolombangara (Dunkerly 1986: 20).

Whereas the gold experiment is still in progress, previous chemical studies of basalt, dacite, and pottery artifacts have demonstrated the power of chemical fingerprinting.