| 单词 | biotite |
| 例句 | Why is biotite called a ferromagnesian mineral, while muscovite is not? Physical Geology 2015-01-01T00:00:00Z Diorite is identifiable by it’s Dalmatian-like appearance of black hornblende and biotite and white plagioclase feldspar. An Introduction to Geology 2017-01-01T00:00:00Z In biotite hornfelses a faint striping may indicate the original bedding of the unaltered rock and corresponds to small changes in the nature of the sediment deposited. Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 6 "Home, Daniel" to "Hortensius, Quintus" 2012-03-15T02:00:32.250Z The snowy white feldspar and quartz set off the glittering crystals of hornblende and biotite wonderfully. M lange et Trois: A Trip Across Subduction Zone Madness 2012-03-07T22:15:00.213Z The biotite is brown; the hornblende brown or greenish brown; the augite usually green. Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 8 "Cube" to "Daguerre, Louis" 2012-01-31T03:00:17.257Z Rearrange the following minerals in order of increasing metamorphic grade: biotite, garnet, sillimanite, chlorite. Physical Geology 2015-01-01T00:00:00Z Two frequently found micas are dark-colored biotite, frequently found in granite, and light-colored muscovite, found in the metamorphic rock called schist. An Introduction to Geology 2017-01-01T00:00:00Z They are excessively variable in their mineralogical composition, and very often alternate in thin seams with biotite hornfels and indurated quartzites. Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 6 "Home, Daniel" to "Hortensius, Quintus" 2012-03-15T02:00:32.250Z The commonest accessory minerals are tourmaline, topaz, apatite, fluorspar and iron oxides; a little felspar more or less altered may also be present and a brown mica which is biotite or lithionite. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 5 "Greek Law" to "Ground-Squirrel" 2011-12-05T03:00:51.527Z In the hand specimen many of the hornblende and biotite dacites are grey or pale brown and yellow rocks with white felspars, and black crystals of biotite and hornblende. Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 8 "Cube" to "Daguerre, Louis" 2012-01-31T03:00:17.257Z In some cases, hornfels has visible crystals of minerals like biotite or andalusite. Physical Geology 2015-01-01T00:00:00Z Green augite and hypersthene form a considerable part of these rocks, they may contain also biotite, hornblende and quartz. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" 2011-11-13T03:00:13.177Z Sphene, biotite and iron oxides are the other common constituents, but these rocks show much variety of composition and structure. Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 6 "Home, Daniel" to "Hortensius, Quintus" 2012-03-15T02:00:32.250Z Muscovite and biotite may both occur in the same rock; in other cases only one of them is present. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 2 "Gloss" to "Gordon, Charles George" 2011-10-31T02:00:28.703Z Dark-brown biotite, although by no means an important constituent of these rocks, occurs in many of them. Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 4 "G" to "Gaskell, Elizabeth" 2011-08-24T02:00:20.690Z Commonly even very felsic rocks will not have biotite or muscovite because they may not have enough aluminum or enough hydrogen to make the OH complexes that are necessary for mica minerals. Physical Geology 2015-01-01T00:00:00Z Exceptions to this sequence are unusual; sometimes the first of the felspars have preceded the hornblende or biotite which may envelop them in ophitic manner. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" 2011-11-13T03:00:13.177Z Each mineral may also enclose particles of the others; in the quartz, for example, small crystals of graphite, biotite, iron oxides, sillimanite or felspar may appear in great numbers. Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 6 "Home, Daniel" to "Hortensius, Quintus" 2012-03-15T02:00:32.250Z EPIDIORITE, in petrology, a typical member of a family of rocks consisting essentially of hornblende and felspar, often with epidote, garnet, sphene, biotite, or quartz, and having usually a foliated structure. Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 6 "English Language" to "Epsom Salts" 2011-02-19T03:00:59.807Z The specific gravity of biotite is, as a rule, higher than that of other micas, varying from 2.7 to 3.1 according to the amount of iron present. Encyclopaedia Britannica, 11th Edition, Volume 3, Slice 7 "Bible" to "Bisectrix" 2010-12-20T17:12:05.780Z To be more specific, felsic rocks typically have biotite and/or amphibole; intermediate rocks have amphibole and, in some cases, pyroxene; and mafic rocks have pyroxene and, in some cases, olivine. Physical Geology 2015-01-01T00:00:00Z Often they enclose dark crystals of biotite and hornblende, arranged zonally. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" 2011-11-13T03:00:13.177Z Slates, shales and clays yield biotite hornfelses in which the most conspicuous mineral is black mica, in small scales which under the microscope are transparent and have a dark reddish-brown colour and strong dichroism. Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 6 "Home, Daniel" to "Hortensius, Quintus" 2012-03-15T02:00:32.250Z They consist essentially of plagioclase felspar, with hornblende or augite, and may contain also biotite, quartz and a limited amount of orthoclase. Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 2 "Anjar" to "Apollo" In volcanic rocks, and in nearly all other kinds of igneous rocks with the exception of granite, biotite occurs to the exclusion of the muscovite. Encyclopaedia Britannica, 11th Edition, Volume 3, Slice 7 "Bible" to "Bisectrix" 2010-12-20T17:12:05.780Z The equation shown here is for olivine, but it could apply to almost any other ferromagnesian silicate, including pyroxene, amphibole, or biotite. Physical Geology 2015-01-01T00:00:00Z The aplites, pegmatites, graphic granites and muscovite granites are usually richest in silica, while with increase of biotite and hornblende, augite and enstatite the analyses show the presence of more magnesia, iron and lime. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" 2011-11-13T03:00:13.177Z Their essential minerals are those of basalt, viz. olivine, augite and plagioclase felspar, while hornblende, ilmenite, apatite and biotite are their commonest accessory ingredients. Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 6 "Dodwell" to "Drama" Some contain biotite, others augite or hypersthene; many have a small amount of quartz. Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 5 "Dinard" to "Dodsworth" The magnesia-micas are now referred to the species biotite and phlogopite, which differ in that the former contains a considerable but widely varying amount of iron. Encyclopaedia Britannica, 11th Edition, Volume 3, Slice 7 "Bible" to "Bisectrix" 2010-12-20T17:12:05.780Z The results of this process are illustrated in Figure 5.10, which shows a granitic rock in which some of the biotite and amphibole have been altered to form the iron oxide mineral limonite. Physical Geology 2015-01-01T00:00:00Z Zircon, apatite and iron oxides are the first; their crystals are small, very perfect and nearly free from enclosures; they are followed by hornblende and biotite; if muscovite is present it succeeds the brown mica. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" 2011-11-13T03:00:13.177Z Closely allied to the chlorites is another group of micaceous minerals known as the vermiculites, which have resulted by the alteration of the micas, particularly biotite and phlogopite. Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 3 "Chitral" to "Cincinnati" The biotite is always brown or yellow; the hornblende usually green, but sometimes brown or yellowish brown in those diorites which have affinities to lamprophyres. Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 5 "Dinard" to "Dodsworth" The angle between the optic axes is usually very small, the crystals being often practically uniaxial; an axial angle of 50� has, however, been recorded in a dark-coloured biotite. Encyclopaedia Britannica, 11th Edition, Volume 3, Slice 7 "Bible" to "Bisectrix" 2010-12-20T17:12:05.780Z Figure 5.10 A granitic rock containing biotite and amphibole which have been altered near to the rock’s surface to limonite, which is a mixture of iron oxide minerals. Physical Geology 2015-01-01T00:00:00Z In other cases the spheroids are simply dark rounded lumps of biotite, in fine scales. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" 2011-11-13T03:00:13.177Z The minerals of diabase are the same as those of dolerite, viz. olivine, augite, and plagioclase felspar, with subordinate quantities of hornblende, biotite, iron oxides and apatite. Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 3 "Destructors" to "Diameter" More rarely biotite and augite exhibit the same relations to the plagioclase. Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 5 "Dinard" to "Dodsworth" Additional minerals found in the coarse schists are calcite, ilmenite, skeleton oblivine, biotite, and hematite. History and Comprehensive Description of Loudoun County, Virginia In other minerals the measurements are not quite the same as in biotite. The Birth-Time of the World and Other Scientific Essays These are probably due to the adhesion of the biotite crystals to one another as they separated from the rock magma at an early stage in its crystallization. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" 2011-11-13T03:00:13.177Z Their commonest minerals are olivine, anorthite, hornblende, augite, biotite and leucite. The Project Gutenberg Encyclopedia Volume 1 of 28 There is some sericite present, also magnetite, resulting from the decomposition of the biotite. The Long Labrador Trail The essential constituents are quartz, orthoclase and plagioclase, and by the addition to these of biotite, garnet, epidote, blue quartz, and hornblende, five types are formed. History and Comprehensive Description of Loudoun County, Virginia The heavy iron atom of the biotite is, doubtless, chiefly responsible for this in biotite haloes. The Birth-Time of the World and Other Scientific Essays In the weathering of granite the quartz suffers little change; the felspar passes into dull cloudy, soft aggregates of kaolin, muscovite and secondary quartz, while chlorite, quartz and calcite replace the biotite, hornblende and augite. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" 2011-11-13T03:00:13.177Z Though consisting mainly of biotite granite, these later intrusions pass by intermediate stages into diorite, as in the area between Balmoral and the head-waters of the Gairn. The Project Gutenberg Encyclopedia Volume 1 of 28 A dark red, finely laminated rock consisting chiefly of decomposed biotite and feldspar, occasional quartz grains and sericite and much iron oxide. The Long Labrador Trail We pushed the ship against a small banded berg, from which Wordie secured several large lumps of biotite granite. South: the story of Shackleton's 1914-1917 expedition It is apparent that the experiment on the biotite has a direct bearing on the validity of the radioactive method of estimating the age of the rocks. The Birth-Time of the World and Other Scientific Essays This young scientist, too, cherished loving thoughts about Angelina, thoughts of a more earthly and volcanic tinge; certain definite projects which made him forget, at times, his preoccupation with biotite, perlite, magnetite, anorthite, and pyroxene. South Wind In certain minerals, notably the brown variety of mica known as biotite, the microscope reveals minute circular marks occurring here and there, quite irregularly. The Birth-Time of the World and Other Scientific Essays A fine grained compact gray rock, of aggregate structure, consisting chiefly of quartz, plagioclase and biotite, and the alteration products epidote and sericite. The Long Labrador Trail It is well known that there is in biotite a maximum absorption of a plane-polarised light ray, when the plane of vibration coincides with the plane of cleavage. The Birth-Time of the World and Other Scientific Essays The biotite is in the centre of the field. The Birth-Time of the World and Other Scientific Essays For in that case, as we have seen, we can at once account for the definite radius as simply representing the range of the ray in biotite. The Birth-Time of the World and Other Scientific Essays In most of the cases mentioned above the structure evidently shows the existence of concentric spherical shells of darkened biotite. The Birth-Time of the World and Other Scientific Essays Minerals present are hornblende, biotite, plagioclase, pyroxene, quartz and the alteration products from the feldspar. The Long Labrador Trail Under the microscope some of the biotite has a green coloration from decomposition and is surrounded by strong pleochroic halos. The Long Labrador Trail The fine striated appearance of the biotite is due to the cleavage of that mineral, which is cut across in the section. The Birth-Time of the World and Other Scientific Essays The principal minerals are, plagioclase, biotite and microcline, with smaller quantities of quartz, iron oxide, pyroxene and garnet. The Long Labrador Trail A white rock having a peculiar mottled appearance due to the inclusions of decomposing biotite which project from the surrounding mass of calcite. The Long Labrador Trail The minerals at contact are quartz, biotite, magnetite and hornblende. The Long Labrador Trail The labradorite contains inclusions of rutile and biotite and has a well-developed wedge structure and cross fracture due to the pressure and shearing which it has undergone. The Long Labrador Trail In this manner the conditions in the complex molecule of biotite, tourmaline, etc., may be quite as effective in preventing initial recombination as the most effective electric force we could apply. The Birth-Time of the World and Other Scientific Essays |
| 随便看 |
英语例句辞典收录了117811条英语例句在线翻译词条，基本涵盖了全部常用单词及词组的例句翻译及用法，是英语学习的有利工具。