These are overlaid by conglomerates, tuffs, sandstones and arkoses, which perhaps do not all belong to the same period.
Quartzites, Conglomerates and Shales of Nkandhla, Umfolosi river.
The Upper Devonian was a period of marine retreat; the crustal disturbances of the Lower Devonian were renewed and great quartz-pebble beaches were formed on the rising shore lines, producing the West Coast Range conglomerates of Tasmania, and the similar rocks to the south-east of Mansfield in Victoria.
The mountains both in Victoria and New South Wales were snow-capped, and glaciers flowed down their flanks and laid down Carboniferous glacial deposits, which are still preserved in basins that flank the mountain ranges, such as the famous conglomerates of Bacchus Marsh, Heathcote and the Loddon valley in Victoria, and cf Branxton and other localities in New South Wales.
They include gypsum, dolomite, conglomerates, phyllites, and a basic series of eruptive rocks (gabbros, peridotites, serpentines).
A group of highly inclined quartzites, altered conglomerates and jasperoid rocks which crop out on the Umhlatuzi river, between Melmoth and Nkandhla and on the White Umfolosi river above Ulundi Ph ins, is considered by Anderson to represent some portion of the Lover Witwatersrand series.
Ac cording to Molengraaff it includes the two following series: - An upper group including the auriferous conglomerates of the Rand: Witwatersrand Series.
They show a great variety of type made up of slates, quartzites, occasional conglomerates, schists with large masses of intrusive granites and gneiss.
There are occasional bands of conglomerates, sometimes auriferous.
The upper group consists of conglomerates, grits and quartzites with a few bands of shales.
It has obtained notoriety from the conglomerates along certain bands containing gold, when they constitute the famous " banket."
The conglomerates consist almost entirely of pebbles of quartz set in a hard 2 At the Standerton gauge on the Vaal in 1905-1906, a year of extreme drought, the total flow was 8,017,000,000 cub.
Near Reitzburg the coarse conglomerates reach a thickness of 400 ft.
Sandstones, quartzites, conglomerates and breccia make up the formation.
Sandstones and conglomerates with coal-seams at Vereeniging.
The Black Reef series of quartzites and conglomerates and dolomite form a narrow outcrop resting unconformably upon the last-mentioned system.
At Jebel-kahar and west of Traras, Pomel attributes certain conglomerates, red sandstones and purple and green shales to the Permian.
Limonite often forms a cementing medium in ferruginous sands and gravels, forming "pan"; and in like manner it is the agglutinating agent in many conglomerates, like the South African "banket," where it is auriferous.
To these is added water, which combining chemically with the cement conglomerates the whole mixture into a solid mass, and forms a rough but strong artificial stone.
The Molasse, in the neighbourhood of the mountains, consists chiefly of conglomerates and sandstones, and the Flysch consists of sandstones and shales; but the Molasse is of Miocene and Oligocene age, while the Flysch is mainly Eocene.
North of the Danube, in Germany as in England, red sandstones, shales and conglomerates predominate, together with beds of gypsum and salt.
They consist of breccias, conglomerates, sandstones, marls, and limestones, with seams of coal and lignite.
The diamond is here found in ancient sandstones and conglomerates, and in the river gravels and sands derived from them.
The sandstones and conglomerates belong to the Vindhyan formation and overlie the old crystalline rocks: the diamantiferous beds are well defined, often not more than 1 ft.
Next follow the Bala Beds, which, with the succeeding Lower and Upper Llandovery shales, sandstones and conglomerates, form the sparsely populated sheepwalks and valleys which occupy most of the north-western part of the county.
These rocks are much folded and the shales are locally cleaved into slates, while the sandstones and conglomerates form scarps and ridges.
Crystalline rocks crop out at several capes; Cretaceous limestones, containing an abundant and specific fauna of gigantic ammonites, occur at Dui on the west coast, and Tertiary conglomerates, sandstones, marls and clays, folded by subsequent upheavals, in many parts of the island.
In the basin of the gorges Moray Firth some fine examples may be seen on the Nairn and Findhorn, while on the west side of the Cromarty Firth some of the small streams descending from the high grounds of the east of the shire of Ross and Cromarty have cut out defiles in the Conglomerates, remarkable for their depth and narrowness.
There occur also below the Lias on some parts of the west coast unfossiliferous red sandstones, conglomerates and breccias, presenting lithological resemblance to the Rhaetic group of England.
Red sandstones and conglomerates, probably of the same age, attain a thickness of several hundred feet at Gruinard Bay on the west coast of the county of Ross and Cromarty.
The lower part of the Kimmeridge Clay is probably represented by sandstones and conglomerates, forming the highest beds of the series in Sutherland.
There are shales, conglomerates and sandstones; and all round the island the valleys are filled with alluvial deposits on a much more extensive scale than might have been looked for seeing that no river in the island has a course longer than some 6 m.
Few seas are more prolific in fish than the Persian Gulf and the Gulf of Oman; the great proportion of known species are edible and many have a commercial value for the isinglass or oil Shelly conglomerates and dead coral reefs of the littoral; red sandhills of the coast of Trucial Oman; alluvium of Turkish Iraq; river and lake deposits of Oman and the interior of Persia.
These ancient rocks, which form the foundation of the country, are overlaid unconformably by a series of conglomerates and sandstones, generally unfossiliferous and often red or purple in colour, very similar in character to the Nubian sandstone of Upper Egypt.
The central plateau consists of ancient crystalline rocks with granites overlain by unfossiliferous sandstones and conglomerates considered to be of Palaeozoic age.
Carboniferous beds, consisting chiefly of slates, sandstones and conglomerates, are found in the south-eastern provinces.
Consisting of red sandstones, mudstones and conglomerates, they are inclined at high angles usually away from the granite massif and the encircling metamorphic rocks.
The Upper Old Red Sandstone, composed of red sandstone and conglomerates, is only sparingly developed.
The Triassic rocks are arranged in two groups, a lower, composed of conglomerates and sandstones, and an upper one consisting of red and mottled shales and marls with thin sandstones and nodular limestones.
The Tertiary system includes conglomerates, sandstones, limestones and marls, which appear to be of Eocene, Oligocene and Miocene age.
Muds, sands, grits and conglomerates are the predominant types.
Thus, we find them more frequently, folded, tilted and cleaved; the muds have become shales, slates, phyllites or schists, the grey and red sands and conglomerates have become quartzites and greywackes, while the limestones are very generally dolomitized.
The Cambrian system is covered by his stages "B" and "C"; the former a barren series of conglomerates and quartzites, the latter a series of grey and green fissile shales 1200 ft.
In northern France Cambrian rocks, mostly purple conglomerates and red shales, rest with apparent unconformability upon pre-Cambrian strata in Brittany, Normandy and northern Poitou.
In the Rennes basin limestones - often dolomitic - are associated with quartzites and conglomerates; silicious limestones also occur in the Sarthe region.
In Russian Poland is a series of conglomerates, quartzites and shales; some of the beds yield a Paradoxides fauna.
The shores of the Bosporus are composed in the northern portion of different volcanic rocks, such as dolerite, granite and trachyte; but along the remaining course of the channel the prevailing formations are Devonian, consisting of sandstones, marls, quartzose conglomerates, and calcareous deposits of various kinds.
The deposits are marine, consisting mainly of sandstone and limestone, together with tuffs and conglomerates of porphyry and porphyrite.
The Witwatersrand series of the Transvaal includes auriferous conglomerates which have been worked since 1886 and constitute the richest gold-mines in the world.
But in the upper Cretaceous and lower Tertiary, especially in north-western Baluchistan, there is an extensive development of volcanic tuffs and conglomerates, which are probably contemporaneous with the Deccan Traps of India.
Recent; d =Upper Siwalik conglomerates c =J,fiddle Siwalik sandstones; b=Lower (Nahan) siwalik.s; a .
The deposits in these basins consist largely of coarse sandstones and conglomerates, amongst which lie seams of coal.
Coalbearing clays containing fresh-water molluscs and dicotyledonous plants, as also conglomerates, alternate with the sandstones in these Tertiary deposits.
Very extensive layers of melaphyre and andesite, as also of conglomerates and volcanic tuffs, cover the middle portions of the peninsula.
The Lower Carboniferous beds are represented by conglomerates and sandstones with some shales and limestones.
13,650 Geologically, perhaps, the most interesting rocks in the Carboniferous are the glacial conglomerates, containing ice-scratched, erratic blocks.
The Triassic rocks, red sandstones, marls and conglomerates cover a broad area in the Midlands in Worcestershire, Warwickshire and Leicestershire, whence they may be followed south-westward through Somerset to the coast at Sidmouth, and northward, round either flank of the Pennine Hills, through Nottinghamshire and Yorkshire to Middlesbrough on the one hand, and upon the other through Staffordshire, Cheshire and Lancashire to Carlisle.
The Ibiquas beds consist of conglomerates and grits.
The Ongeluk volcanic series, consisting of lavas and breccias, conformably overlies the Griquatown series; while the grits, quartzites and conglomerates of the Matsap series rest on them with a great discordance.
The most remarkable deposits are the conglomerates of the Dwyka series.
These are formed to a large extent of thick conglomerates which are full of pebbles and boulders of granite and schist.
The Alai is a well-defined ridge with steep slopes, and both it and the Terek-tau, which prolongs it towards the Kokshal-tau, are flanked next the Ferghana valley by what appear to be the old uplifted strata both of the old Palaeozoic series of metamorphic limestones and of the newer Tertiary series of softer conglomerates and sandstones.
In some places limestones appear as projections from the range; at others conglomerates and Tertiary clay marls form the outermost fold."' On the north versant of the ranges the rainfall increases from the foot of the mountains upwards, and at woo-10,000 ft.
The conglomerate bands and quartzites contain large quantities of iron pyrites deposited subsequent to their formation, that in the conglomerates containing the gold.
The geological formations thus exposed show that the plateaus are composed of a base of eruptive material, overlaid by enormous deposits of reddish sandstones, conglomerates and quartzites, exposed in parts to a depth of 2000 feet.