长安大学资源学院英语文献翻译学院地球科学与资源学院专业资源勘查工程学生姓名张桃学号 2指导教师张亚敏2015年6月18日Title:Orthomagmatic ore depositsOne.Orthomagmatic ore depositsThe magma contains a certain number of metal and volatile components of the silicate melt. All kinds of magma after crystallization and differentiation, make the forming materials dispersed in the magma gathered and formed deposits.And this deposits is called magmatic deposits.Magmatic deposits formed in the magmatic stage, the source of the material of the deposit is the main ore-bearing magma.Magmatic deposits is the product of the magma by crystallization and differentiation, and generally have the following properties:1、Deposits have the mainly relationship with the mafic and ultramafic rocks.And a small number of magmatic deposits with alkaline rocks or magmatic carbonatite-related. Mineralization and diagenesis often begin at the same time.And this is typical of syngenetic ore deposits. Few mineralization of the magmatic deposits may be continued to a later time, but generally does not exceed a total period of magmatic activity.2、The magmatic deposits ore body majority presentstratiform, lenticular and podiform and so on.And they produced in the magma body,and the wall rock of containing ore is the mother rock.Few cases,orebody presenting vein and stockwork enter the wall rock which outside of the mother rock Between the ore body and the wall rock generally is gradual change or rapid gradual change relationship.Only penetration magmatic deposits have the clear boundaries with the wall rock.3、Except the rare and rare earth elements deposits of the magmatic carbonatite due to special causes have some alteration about the wall rock,the vast majority of magmatic deposits surrounding rock does not have a significant alteration phenomenon.4、The ore and the wall rock basically have the same mineral composition, when the useful minerals of the rock body aggregate and reach a certain size,they become the orebody.5、The ore of magmatic deposits oftenhave,disseminated,the banded,eye porphyritic,dense massive,brecciated and so on,ore structure.The ores structure can be broadly divided into the following categories:I.Structure sub-the different magmatic condensate crystalline or stacking interactions; II.Reflect the structure of the immiscible fluid crystallization process III.Reflect thechanges in the structure of the physical and chemical conditions.IV.Epigenetic structure.6、The magmatic deposits forming temperature is high, generally between 1200 to 700 ° C. The mineralization depth changes,generally formed in the ground a few kilometers to tens of kilometers.Tow.The formation conditions of magmatic deposits Magma deposits are mainly derived from the magma, it is the combined effects of the product by a variety of geological factors, which playing a leading role is the geochemistry of ore-forming elements traits, the magmatic rock conditions, tectonic conditions and physical and chemical conditions and so on.1、Control the conditions of magmatic rocks formed by magmatic depositsMagma is the main provider of the metallogenic material of the magmatic deposits and the medium of containing mineral medium.Therefore,how much of the content of useful components of magma is the possibility of the formation of magmatic deposits.I.Magmatic rocks metallogenic specializationMetallogenic specialization of magmatic rocks in thegenesis of magmatic rocks with endogenous deposits showed regular contact, and specific types of magmatic rocks are often produced specific types of deposits.a)With mafic and ultramafic intrusive rocks related depositsMafic and ultramafic rock is the complex igneous complex formed by the combination of a variety of rock types, rock types from a single rock composed of rock mass is relatively rare.The size of the rock mass ranging mostly small,and rock strains, rock cover, rock, bedrock is the most common form of the rock mass. With facies and the different combinations,the mafic and ultramafic rocks can be divided into three types.b)Mineral deposits associated with syenite, nepheline syenite and carbonate igneous complexRelating to magmatic deposits of these rocks are mostly produced with the form of rock strain,the different components of rock mass facies zone often has ring distribution.II.The role of the volatile components in the magmaThe magma volatile components have the low melting point,highly volatile and they can delay the condensation rate of the magma, make the magma have more fully differentiation.III.Magmatic assimilation have an influence on the mineralization of the magma DepositsIV.Beyond one period of magma intrusion on control of the mineralization2、Tectonic conditions that control the formation of magmatic depositsTectonics have a major impact on the type of magmatic deposits, distribution, the most magmatic deposits associated with mafic and ultramafic igneous rocks on the Causes and space. Mafic and ultramafic magma formed by partial melting of mantle material,so the deep fault cuts through the crust to reach the upper mantle have a strict control effect on the mafic, ultramafic rocks and magmatic deposits which have some relationship with them.Three.Magmatic deposits formation and its characteristics1、The process of the magma’s useful components analysis, aggregation and positioning is called magmatic mineralization. Because the magmatic deposits mafic - ultramafic petrogenesis process is very complex, the mineralization also isvaried.According to the way and feature of the mineralization,magmatic mineralization can be divided into four categories,the crystallization differentiationmineralization, melting away from the mineralization the magma eruption mineralization and magma eruption mineralization.When magma is condensed, with the temperature gradually decreased, the various mineral sequentially from which crystallized out, result in magma changing,and the magma changes in the composition promote the crystallization of certain components, liking magma composition changed with the crystallization process is called crystallization differentiation.2、Magmatic liquation mineralization and liquation depositMagmatic liquation, also known as liquid separation action or immiscibility, refers to the the uniform composition magma melt with decreasing temperature and pressure separated into two components of different melt role.3、Magmatic eruptions and effusive the Mineralization its depositMagma outbreak mineralization kimberlite magma, together with early crystallized olivine, pyrope, diamond crystals and xenoliths along deep faults,and rise rapidly emplaced at the surface produce 2 to 3 kilometers outbreak and the role of the deposit is formed.The magmatic eruption mineralization is the ore-bearing lava spray overflow to the surface or penetration into the crater near volcanic series along certain channels, the the condensate accumulation of deposit formation. Formed deposits called magma eruption deposits.Four.Implications for researchMagmatic deposits having very important industrial significance, most of chromium, nickel, platinum group elements as well as a substantial portion of iron, copper, titanium, cobalt, phosphorus, niobium, tantalum and rare earth elements and other deposits are all from magmatic deposits in the world. Mineralization conditions, the genesis of magmatic deposits and distribution law is of great significance.题目：岩浆矿床一、岩浆矿床岩浆是含有一定数量金属及挥发性组分的硅酸盐熔融体。