無機(jī)非金屬材料專業(yè)英語-寶石材料地質(zhì)的介紹

1、Unit 26 An Introduction to the Geology of Gem Materials寶石材料地質(zhì)的介紹n1、The division of the sciences into various subjects, such as biology, chemistry, geology and physics, is convenient for their study, and for teaching purposes. n為了方便研究和教學(xué)，科學(xué)可以劃分為不同的學(xué)科，如生物學(xué)、化學(xué)、地質(zhì)學(xué)和物理學(xué)。 nTo study any of these subjects e

2、ffectively, the student should have, at least, some knowledge and understanding of the related sciences.n為了有效學(xué)習(xí)任何一個(gè)學(xué)科，學(xué)生至少必須具備相關(guān)科學(xué)的一些知識和理解。 n Gemology is no exception to this and a basic understanding of the geology and mineralogy of gemstones will be helpful.n寶石學(xué)也不例外，具備基本的寶石的礦物學(xué)和地質(zhì)學(xué)的基本知識對學(xué)習(xí)寶石學(xué)非常有幫助

3、。The Crust（地殼）（地殼）n2、The solid crust of the continents on which we live varies from about 25km (15 miles) to about 70km (45 miles) in thickness. n我們居住的陸地固體殼層厚度大約是25km到70km。 nUnder the oceans it averages about 6km (4 miles).n海洋下厚度平均約為6km。n3、Much of the crust has a thin covering composed chiefly of se

4、dimentary material. n大部分殼層由一層稀薄的主要由沉積巖材料組成的包覆層。 nThis is material, which has been deposited by wind, rain, and seawater or by chemical precipitation, and then cemented or compressed to form rocks. n這些材料是由風(fēng)、雨和海水沉積而成，或者是化學(xué)沉積，而后膠凝或壓實(shí)形成巖石。 nThese sedimentary rocks are chiefly limestone, clay, shale and

5、sandstone.n這些沉積巖主要是石灰?guī)r、黏土、頁巖和砂巖。n4、Granites, basalt and metamorphic rocks form the major part of the crust (the middle and lower layers). n花崗巖，玄武巖和變質(zhì)巖形成了地殼（中間和底層）的重要組成部分。 nThe first two have been formed by the solidification of molten rock and are termed igneous rocks. n前兩個(gè)由熔巖凝固形成，被稱為“巖漿巖”巖石。 nMetam

6、orphic rocks are any rocks that have undergone change (metamorphism), principally by heat or pressure in the depths of the earth.n變質(zhì)巖是經(jīng)歷了變質(zhì)作用而成的普通的巖石，主要是由于在地球深處的熱或壓力所致。n5、The middle layer of the crust varies between 16 and 24km (1015 miles) in thickness, beneath the continental landmasses. n地殼的中間層的厚

7、度在16至24km不等（1015英里），在大陸陸地的下方。 nIt is sometimes referred to as granitic layer, as granite is its main constituent.n n它有時(shí)被稱為“花崗巖層”因?yàn)榛◢弾r是它的主要成分。 nSimilarly the lower layer is known as the basaltic layer, as basalt and other basic rocks predominate.n同樣，低層被稱為“玄武巖層”，因?yàn)橐詾樾鋷r和其他基本巖為主。n6、In the Atlantic, the

8、 Pacific and other major oceans, the crust is very thin, and its major component is the basaltic layer. n在大西洋，太平洋和其他主要海洋，地殼很薄，它的主要成分是玄武巖層。The Intermediate Zone or Mantle（過渡區(qū)或地幔）（過渡區(qū)或地幔）n7、Beneath the crust lies the mantle with a thickness of about 2900km (1800 miles).n位于下方的地殼的地幔厚度約為約2900km（厚度1800英里）

9、。nIt is hot and plastic, in contrast to the cooler and more rigid crust.n和冰冷剛硬的地殼相比它是熱的而且具有塑性。The Core（地心，中心）（地心，中心）n8、The core extends about 3500km (2150 miles), from the mantle to the center of the Earth.n地心從地幔到地球中心延伸大概至3500km。nScientists are uncertain as to its temperature and its composition.n關(guān)于

10、它的溫度和組成科學(xué)家都是不確定的。n9、One theory is that it is chiefly composed of molten nickel and iron (partly solid, partly molten). (Using the chemical symbols for these two elements, Ni and Fe respectively, geologists sometimes call this portion of the Earth, NIFE. )n一種理論說它主要是由熔融的鎳和鐵組成（部分溶解部分還是固體）（分別用化學(xué)式Ni和Fe來表

11、示，地質(zhì)學(xué)家有時(shí)稱地球的這部分為NIFE）n10、The core, mantle and crust each have different physical characteristics. n中心、地幔和地殼分別具有不同的物理性質(zhì)。 n The core is under the highest pressure, and its temperature is higher than those of the mantle and crust. Because of these differences there are discontinuities and relative move

12、ment between these regions n中心溫度最高，它的溫度高于地幔和地殼。由于這些不同導(dǎo)致這些區(qū)域間中斷和相對運(yùn)動。n11、It is these factors, together with the effects of gravity and the forces exerted by the other members of our solar system, that are considered to be responsible for such natural phenomena as volcanic eruptions, earthquakes, the

13、slow drift of the continents and the buckling of the surface of the Earth to form mountain ranges and valleys.n以上這些因素以及萬有引力和太陽系其它星球施加的力被認(rèn)為是形成這些自然現(xiàn)象如火山噴發(fā)、地震、板塊移動和地球板塊擠壓形成山脈和流域的原因。n12、The surface features of the Earth are produced by two sets of opposing forces - destructive and constructive.n地球地貌由兩種相

14、反作用力產(chǎn)生：破壞性的和建設(shè)性的。n13、The destructive forces, such as those due to wind, rain, rivers, glaciers, the action of the sea and some earthquakes, continuously break down the rocks, and minerals, which form the features of the Earths crust. n破壞力如由風(fēng)、雨、河流、冰川、海洋和一些地震引起的力會連續(xù)不斷的破壞巖石和礦物質(zhì)，這些都是形成地殼形貌的因素。 nThis is

15、a slow never-ending process.n這是一個(gè)緩慢的無休止的過程。n14、The constructive forces , due to such Earth movements as the drift of the landmasses (plate tectonics) and volcanic activities, are continually forming new features. n由于地球運(yùn)動所致，如地幔漂移（板塊構(gòu)造學(xué)）和火山活動，建設(shè)性力會持續(xù)形成新的形貌。 nSome of these changes may be relatively rap

16、id, as in the case of volcanoes, whilst others may take millions of years, as with the gradual movement of the continents. n其中的一些變化可能相對較快，比例火山，其它的可能會需要數(shù)百年，如大陸板塊的持續(xù)移動。nNevertheless, the formation is continuous.n不管怎樣，構(gòu)造是持續(xù)的。The Composition of the Earth（地球組成）（地球組成）n15、There are 92 naturally occurring e

17、lements in the Earths crust and, of those, eight account for approximately 98% of the crust. n有92個(gè)天然元素存在于地殼中，其中，八種元素占了地殼的大約98%。 nThey are oxygen (46.6% ), silicon (27.2% ), aluminum (8.1 %), iron (5.0%), calcium (3.6%), sodium (2.8%), potassium (2.6%) and magnesium (2.1%).n它們是氧（46.6），硅（27.2），鋁（8.1），

18、鐵（5.0），鈣（3.6），鈉（2.8），鉀（2.6）和鎂（2.1 ）。 n16、It should be realized, however, that the elements forming the Earth are not evenly distributed through the crust, for example basalt has a composition different from granite, and both these differ from limestone.n然而，應(yīng)該看到，這些構(gòu)成地球的元素并非均勻分布的，例如由玄武巖組成和花崗巖不同，這兩種和石灰

19、巖又都不同。n17、These natural elements combine together chemically to form compounds and some of these chemical compounds are minerals.n這些自然元素經(jīng)過化學(xué)作用結(jié)合在一起形成化合物，其中的一些化合物是礦物質(zhì)。n18、A mineral, in most cases, is a naturally formed inorganic substance, which possesses a definite chemical composition and a definit

20、e atomic structure.n在大多數(shù)情況下，一種礦物質(zhì)是自然形成的無機(jī)物，這種無機(jī)物具有確定的化學(xué)成分和確定的原子結(jié)構(gòu)。n19、A mineral may consist of just one element (e. g. diamond is composed of just one element - carbon) or of several elements, chemically combined to form a compound (e. g. quartz is a compound made up of silicon and oxygen atoms).n一種礦物質(zhì)可能只有一種元素組成，如金剛石只有碳元素組成，或者由幾種元素組成，化學(xué)結(jié)合形成化合物，例如石英就是由氧原子和硅原子組成的化合物。n20、Rocks, however, consist of mine