trachytes

The trachytes of the lower formation exhibit outstanding cliff faces at The Steamers, in Emu Creek and at Mount Castle on the escarpment.

Central Eastern Rainforest Reserves, Australia 2008

Roedder (1972) found the former in granitic nodules ejected during eruptions of peralkaline trachytes from Ascension Island.

Evidence for Fluid Saturation and Degassing 2008

The latter show the anatomy of the land -- tufas, lavas, conglomerates, trachytes, trachydolerites, and basalts of various kinds.

To the Gold Coast for Gold A Personal Narrative in Two Volumes.—Volume I Richard Francis Burton 1855

Whilst the country to the north-east of the lakes is mostly composed of rocks, of great age, geologically, such as schists, quartzites, and old dolerytic rocks, with newer but still ancient trachytes, that to the south-west of them is formed principally of recent volcanic tufas and lavas, the irruption of which has not yet ceased.

The Naturalist in Nicaragua Thomas Belt 1855

The rocks were trachytes, and the soil seemed fertile, but there was very little of it cultivated.

The Naturalist in Nicaragua Thomas Belt 1855

The central bed allows no short cut across: it is a series of rubbish-heaps, parasitic cones, walls, and lumps of red-black lavas, trachytes, and phonolites reposing upon a deluge of frozen volcanic froth ejected by early eruptions.

To the Gold Coast for Gold A Personal Narrative in Two Volumes.—Volume I Richard Francis Burton 1855

Dr.T. Sterry Hunt calls them porphyroid trachytes.

The Andes and the Amazon Across the Continent of South America James Orton 1853

A similar disengagement of vapours, joined to the elastic force of the gases, which penetrate strata softened and raised up, appears sometimes to have given great extent to the caverns found in trachytes or trappean porphyries.

Travels to the Equinoctial Regions of America 1851

These three transverse chains have no active volcanoes; we know not whether the most southern, like the two others, be destitute of trachytes or trap-porphyry.

Travels to the Equinoctial Regions of America 1851

The alumite of Tolfa, which, since my return to Europe, I have examined on the spot, conjointly with Gay – Lussac, has, by its oryctognostic characters and its chemical composition, a considerable affinity to compact feldspar, which constitutes the basis of so many trachytes and transition-porphyries.

Travels to the Equinoctial Regions of America 1851