స్థలాలు మరియు క్వార్ట్జ్ మరియు ఇతర స్ఫటికాకార ఖనిజాలు ఉన్న ఒక బూడిద అగ్నిపర్వత రాక్,

dacite's Usage Examples:

by dacites and block and ash flows that were later intruded by dacitic porphyries, associated with hydrothermal alteration.

include rhyolite and dacite lavas.

has a green grey porphyry with a dacite like composition, and visible white feldspar crystals.

This makes rhyodacite the extrusive equivalent of monzogranite.

Pinatubo was andesite and dacite in the pre-climactic phase but only dacite in the climactic phase.

Typical intermediate rocks include andesite, dacite and trachyandesite among volcanic rocks and diorite and granodiorite among.

called the Pagosa Peak Dacite, made of dacite that is very similar to that of the Fish Canyon Tuff.

Rhyodacite then describes a fine-grained igneous rock containing between 20% and 60% quartz and in which plagioclase makes up about two-thirds of the total feldspar content.

majority are of intermediate composition (such as Santiaguito, dacite-andesite, present day) The characteristic dome shape is attributed to high viscosity.

Andesite shows similar composition to dacite samples, though sodic plagioclases and amphiboles are not as common.

the source of a 15 km (9 mi) long broad dacite lava flow with prominent wrinkled ridges.

Rhyodacite is a volcanic rock intermediate in composition between dacite and rhyolite.

quartz and feldspar content, rhyodacite commonly contains phenocrysts of andesine, biotite, hornblende, and pyroxene.