Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: August 5, 2024
Both these rocks are composed of triclinic feldspar and augite with more or less olivine, magnetic or titaniferous oxide of iron, and usually a little nepheline, leucite, and apatite; basalt usually contains considerably more olivine than melaphyre, but chemically they are closely allied, although the melaphyres usually contain more silica and alumina, with less oxides of iron, lime, and magnesia, than the basalts.
This division corresponds with that proposed by Bunsen and Durocher for volcanic rocks, upon the results of analyses of a large number of specimens from various districts. Examples: Basalt, Dolerite, Hornblende rock, Diorite, Diabase, Gabbro, Melaphyre, and Leucite lava. Examples: Trachyte, Rhyolite, Obsidian, Domite, Felsite, Quartz-porphyry, Granite.
MELAPHYRE is often quite undistinguishable in external appearance from basalt, for although rarely so heavy, dark-coloured, or compact, it may present at times all these varieties of texture.
The Rowley Hills in Staffordshire, commonly known as Rowley Ragstone, are melaphyre. This name has usually been extended to all granular mixtures, whether of hornblende and feldspar, or of augite and feldspar. The term DIORITE has been applied exclusively to compounds of hornblende and triclinic feldspar.
Limerick in Ireland. The rocks consist chiefly of basalt, dolerite, melaphyre and felstone. Devonian Period. Volcanic rocks of Devonian age occur in the South of Scotland, consisting of felstone-porphyries and melaphyres; also at Boyle, in Roscommon, and amongst the Glengariff beds near Killarney in Ireland. Upper Silurian Period.
His conscience at once spoke out, and in the agony of his remorse he had resort to a hermit who bade him renounce the world, grave for himself a cell in the face of the melaphyre clay the hermit did not give to the rock its mineralogical name and await a token from heaven that he was forgiven.
Word Of The Day
Others Looking