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CHARNOCKITE , a See also:series of foliated igneous rocks of wide See also:distribution and See also:great importance in See also:India, See also:Ceylon, See also:Madagascar and See also:Africa. The name was given by Dr T. H. See also:- HOLLAND
- HOLLAND, CHARLES (1733–1769)
- HOLLAND, COUNTY AND PROVINCE OF
- HOLLAND, HENRY FOX, 1ST BARON (1705–1774)
- HOLLAND, HENRY RICH, 1ST EARL OF (1S9o-,649)
- HOLLAND, HENRY RICHARD VASSALL FOX, 3RD
- HOLLAND, JOSIAH GILBERT (1819-1881)
- HOLLAND, PHILEMON (1552-1637)
- HOLLAND, RICHARD, or RICHARD DE HOLANDE (fl. 1450)
- HOLLAND, SIR HENRY, BART
Holland from the fact that the tombstone of See also:Job See also:Charnock, the founder of See also:Calcutta, is made of a See also:block of this See also:rock. The charnockite series includes rocks of many different types, some being See also:acid and See also:rich in See also:quartz and See also:microcline, others basic and full of See also:pyroxene and See also:olivine, while there are also intermediate varieties corresponding mineralogically to norites, quartz-norites and diorites. A See also:special feature, recurring in many members of the See also:group, is the presence of strongly pleochroic, reddish or See also:green See also:hypersthene. Many of the minerals of these rocks are " schillerized," as they contain See also:minute platy or See also:rod-shaped enclosures, disposed parallel to certain crystallographic planes or axes. The reflection of See also:light from the surfaces of these enclosures gives the minerals often a See also:peculiar See also:appearance, e.g. the quartz is See also:blue and opalescent, the See also:felspar has a milky shimmer like moonshine, the hypersthene has a bronzy metalloidal gleam. Very often the different rock types occur in See also:close association as one set forms bands alternating with another set,or See also:veins traversing it, and where one facies appears the others also usually are found. The See also:term charnockite consequently is not the name of a rock, but of an assemblage of rock types, connected in their origin because arising by differentiation of the same See also:parent magma. The banded structure which these rocks commonly See also:present in the See also:- FIELD (a word common to many West German languages, cf. Ger. Feld, Dutch veld, possibly cognate with O.E. f olde, the earth, and ultimately with root of the Gr. irAaror, broad)
- FIELD, CYRUS WEST (1819-1892)
- FIELD, DAVID DUDLEY (18o5-1894)
- FIELD, EUGENE (1850-1895)
- FIELD, FREDERICK (18o1—1885)
- FIELD, HENRY MARTYN (1822-1907)
- FIELD, JOHN (1782—1837)
- FIELD, MARSHALL (183 1906)
- FIELD, NATHAN (1587—1633)
- FIELD, STEPHEN JOHNSON (1816-1899)
- FIELD, WILLIAM VENTRIS FIELD, BARON (1813-1907)
field is only in a small measure due to crushing, but is to a large extent See also:original,and has been produced by fluxion in a viscous crystallizing intrusive magma, together with differentiation or segregation of the See also:mass into bands of different chemical and mineralogical See also:composition. There have also been, of course, See also:earth movements acting on the solid rock at a later See also:- TIME (0. Eng. Lima, cf. Icel. timi, Swed. timme, hour, Dan. time; from the root also seen in " tide," properly the time of between the flow and ebb of the sea, cf. O. Eng. getidan, to happen, " even-tide," &c.; it is not directly related to Lat. tempus)
- TIME, MEASUREMENT OF
- TIME, STANDARD
time and injection of dikes both parallel to and across the See also:primary foliation. In fact, the See also:history of the structures of the charnockite series is the history of the most See also:primitive gneisses in all parts of the See also:world, for which we cannot pretend to have as yet any thoroughly satisfactory explanations to offer. A striking fact is the very wide distribution of rocks of this group
in the See also:southern hemisphere; but they also, or rocks very similar to them, occur in See also:Norway, See also:France, See also:Germany, See also:Scotland and See also:North See also:America, though in these countries they have been mostly described as pyroxene granulites, pyroxene gneisses, anorthosites, &c. They are usually regarded as being of Archean See also:age (pre-See also:Cambrian), and in most cases this can be definitely proved, though not in all. It is astonishing to find that in spite of their great age their minerals are often in excellent preservation. In India they See also:form the Nilgiri Hills, the Shevaroys and See also:part of the Western See also:Ghats, extending southward to Cape See also:Comorin and re-appearing in Ceylon. Although they are certainly for the most part igneous gneisses (or orthogneisses), rocks occur along with them, such as See also:marbles, See also:scapolite limestones, and See also:corundum rocks, which were probably of sedimentary origin. (J. S.
End of Article: CHARNOCKITE
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