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http://unit.cug.edu.cn/jpkc/dqhx. 李方林 主楼二层最东头 67883033 fanglinli@cug.edu.cn. Introduction to Geochemistry. Why do we learn geochemistry? What is the geochemistry? Properties of the discipline Main Contents Research Methods A brief history and the development trend
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http://unit.cug.edu.cn/jpkc/dqhx 李方林 主楼二层最东头 67883033 fanglinli@cug.edu.cn
Introduction to Geochemistry • Why do we learn geochemistry? • What is the geochemistry? • Properties of the discipline • Main Contents • Research Methods • A brief history and the development trend • How do we learn geochemistry?
Solid Earth Sciences Geology Geophysics Geochemistry Geodesy With the development of earth science, traditional and single geology has not satisfied with the need of scientific research and work. Geochemistry is a marginal subject, it has become an important branch of earth science.
Aim： to understand and grasp geochemical 基本概念Conception 基本原理Rationale 基本方法Method to solve the problem of earth science by geochemical methods step by step. 逐步学会用地质学、地球化学的思维方法和手段解决实际问题（主要是地球科学问题）
I The definition and basic issues of Geochemistry The definition of Geochemistry Perhaps the best explanation would be to state that in geochemistry, we use the tools of chemistry to solve geological problems; that is, we use chemistry to understand the Earth and how it works.
地球化学是研究地球及有关宇宙体的化学组成、化学机制和化学演化的科学（赵伦山，张本仁，1988）。主要研究地壳、地球乃至宇宙的化学组成和元素分布分配集中分散、共生组合与迁移及演化的规律。地球化学是研究地球及有关宇宙体的化学组成、化学机制和化学演化的科学（赵伦山，张本仁，1988）。主要研究地壳、地球乃至宇宙的化学组成和元素分布分配集中分散、共生组合与迁移及演化的规律。 地球化学是研究地球（包括部分天体）的化学组成、化学作用和化学演化的科学（涂光炽，1984） Geochemistry: one kind of science to deal with chemical composition, chemical processes and chemical evolution of earth, including some celestial bodies (Guangzhi Tu, 1984). 地球化学是研究地球和太阳系各行星的化学组成以及在地球演化过程中元素和同位素的运动与变化规律的科学（NSFC,1993）。
object：earth、crust and natural system • form：the chemical movement form of • element and isotope • time：including whole evolution history of • earth, crust and geological process； • 理论研究甚至从元素的形成开始。 • 对于单个元素和同位素来讲，是研究它们 • 的发生、不断发展及螺旋式演化的全部历 • 史；
Characteristics of the subject： Geochemistry is a marginal subject that is combined from geology and chemistry. 1. It is a branch of earth science，对象，方法，思维类同 2. It emphasizes chemical movement（含生物化学运动形式） 3. The foundation is theory of chemistry subject （相对地质学）
To filter one another with neighboring disciplines • The goals of geochemistry are thus no different from those of other fields of earth science; just the approach differs. • On the other hand, while geochemists have much in common with other chemists, their goals differ in fundamental ways.
Basic Issue 1 ： • The composition and variation of element and its isotope in the natural system——元素的丰度规律问题abundance rules，它是一切地球化学研究的基础和起点，地球化学的诞生正是从丰度研究开始。“量”quantity
Basic Issue 2 2. The paragenetic association and element forms in the natural system，包括元素的分配及其晶体化学控制问题。如元素的物态、化合物种类和形式，键型、价态，在晶体结构中的配位位置。“质”quality因为element forms和结合状态是地质作用中物理化学条件的指示剂，不同的存在形式可以反映不同的成因。研究环境、农业问题则更多地考虑有效态。如矿泉水（Sr2+Men+等溶解于水中）但如直接放入一块灰岩（Sr含量很高）Sr2+不一定高。一般选用半风化状态的麦饭石。因此不仅需要研究含量的变化，还要重视paragenetic association and element forms的研究。
Basic Issue 3 3. Migration of element to deal with the dynamic change process of element that including disperses, migrates and collects in spatial-temporal in the process of geology. 即从宏观和微观上研究地质作用过程中元素spatial-temporal分散、迁移和聚集的动态过程 “动” move/migration
Basic Issue 4 4. Evolution，including chemical evolution in solar system, migration history of element and earth evolution. Trace element and isotope is a very good tracer for geological process. 如高山教授研究太古宙地壳的组成，通过沉积岩类研究其岩浆作用，Eu特征。源岩研究--Th、Sc、La、Co等。 in a word, abundance, form, migration and evolution of element and isotope are basic issues.
II. Research Method Geochemcial thinking（研究思路）Thought The macro geological body was be formed in geological process, the micro tracer, the composition of trace element and isotope was formed simultaneity. It contains important information that can indicate the process of geology. 只要应用现代分析测试手段进行测试、分析，便可深入地揭示地质作用的秘密。如扬子板块北缘、华北板块南缘的花岗岩其外观特征没有差异，但其铅同位素组成有明显不同。
from a small clue one can see that is coming On the other hand，geochemistry uses thermodynamic system toanalysis the geological processes；to explain the system and changes of condition in dint of modern theory of chemistry. So geochemistry could realize the processes of geology in higher level. In general：“见微知著” from a small clue one can see that is coming thermodynamic system
地球化学的研究方法，其特点是 Pay attention to geological elements，所研究的对象、体系的地质意义要清楚，即样品必须要有代表性。 Acute thinking of geochemistry，can distinguish microcosmic geochemical information from the geological phenomena. 例：铀矿脉产在花岗岩顶部张裂隙中；矿脉切穿煌斑岩脉地段铀矿化变富；两侧围岩中长石发生“红化”。从这些现象中可以分析出哪些地球化学信息呢？
U is quite soluble in water in its oxidized state, U6+, but is much less soluble in its reduced state, U4+. Many uranium deposits have formed when an oxidized, U-bearing solution was reduced. U6++2Fe2+→2Fe3++U4+O2, ↓（氧化还条件、络离子稳定性，离子颜色） 在岩体顶部的张裂隙中，氧化，U为UO22+铀铣络离子，与其它元素化合成络合物，溶解性强，一旦遇到还原介质（Fe2+、Mn2+、Mg2+）
Method of test，to test the concentration of element and isotope with quantitative analysis. Fieldwork： 1. macro geological phenomena 2. with geohemical thinking to understand the geological phenomena（composition、physical-chemiistry condition—typomorphic mineral、chemical reaction phenomena—altering and metasomatism） 3. sampling（representative、systemic、stat.）
Research method in laboratory： 1. To get the concentrations of element and isotope by the good way. Au，W、Mo，As、Sb、Bi、Hg，Pb，F，Cu，REE，oxides. X-ray fluorescence, ICP-MS, atomic fluorescence, atomic absorption analysis, emission spectroscopy, neutron activation，electrode，chemical spectroscopy. 2. element forms and phase analysis (crystal chemistry, X-ray, differential thermal analysis, probe，partially/selective extraction ).
3. The condition of physical chemistry ： T、P、C、D、 pH、Eh、fO2、fS2、t 4. experimentation simulation 5. Multivariate statistical analysis. Otherwise, prof. Yu chongwen，1986，methodology of geochemistry，earth sciences, in Chinese.
III. A brief history of geochemistry Geochemistry was introduced by the Swiss chemist Schonbein (discover of ozone) in 1838 There were 3 research centers in history： U.S.A.：F.W. Clarke, in 1889 he published a classic paper “The relater abundance of the chemical elements”, 1908, “The Data of Geochemistry”; in many respects the appearance of the fifth edition of The Data of Geochemistry in 1924 marks the end of an era.
Norway：At the same time the original staff of the Geoghysical Laboratory was beginning work in Washington, a new school of geochemistry was growing up in Norway. V.M.Goldschmidt (1888-1947)， 1922-1926，crystal structure，In 1929, He left Oslo for Gottingen; in 1933, the first law of crystal chemistry；1937 “The principles of distribution of chemical elements in minerals and rocks”; to research the composition variety with phase law in his doctor dissertation, it is a great work for geochemistry. “Geochemistry”1954（manuscript by Goldschmidt, edited by A. Muir）
U.S.S.R：in 1920，1930s， V.I. Vernadsky developed the direction of mineral genetic and history，pointed out mineralogy must had the knowledge of distribution and migration of element in crust，he established biogeochemistry and radioelement geochemistry；In 1924，Conception of Geochemistry； A.E. Fersman established principle and method of energy analysis in geochemical process.，called for exploration of geochemistry at first；1934-1939 “Geochemistry” 1-4 volume，great contribution in pegmatitic process and Regional Geochemistry, i.e. “Geochemistry of Russia”; A.P. Vinogradov the composition of crust; evolution of Earth；
After 1930s’， H.C. Urey, American, he won Nobel award, developed geochemistry and established cosmochemistry. In 1931 the 2H（D）was found. Exploited Stable isotope geochemistry, established the chemical classification of meteorite, abundance of elements in universe. The development of geochemistry was from 1950s in China. 侯德封Houdefeng Award 涂光炽(ore deposit)、刘东生(environment)、欧阳自远(cosmochemistry)、傅家谟(organic geochemistry)、 谢学锦 exploration of geochemistry 章申 environmental geochemistry 曹添、於崇文、张本仁、李曙光 刘英俊element geochemistry 黎彤 abundance 高山 李献华 郑永飞 徐义刚
Three stages: • Before 1900: preparing、accumulating data of observed and tested • ~1950 classical，to theory analysis，sum up rule • After 1950 integrate application，to solve some important issues in theory and fact. • 也有人称：孕育萌芽时期（史前至19世纪末）； • 独立成型期（～20世纪中叶）：Clarke;Goldschmidt;Vernadsky;Fersman;Urey;这些先驱为创立地球化学这门边缘学科作出了巨大贡献。 • 稳定发展时期（1950～）
IV：The development trend Advance in Geochemistry (by NSFC) 1. It is a full of vitality young subject； 2. Geochemical research has achieved great success (元素地球化学、矿床地球化学、前寒武纪地球化学、有机地球化学、海洋地球化学、同位素地球化学、天体地球化学、生物地球化学、区域地球化学、地球化学热力学、岩石地球化学……地球化学在横向上，不仅在学科体系内部加强了联系和交叉，而且向其它学科延拓，互相汲取营养，引入其他学科的新成果、新方法，取得了巨大的进展；在纵向上，各学科向着纵深发展，有可能形成一门新的学科—地球物质科学；有人认为，地球物质科学将是地质学、地球物理学和地球化学的接合点。)；
3. It is foundation of geochemistry development that improved the analyzing method and experimental technology。 研究领域的扩大和众多新生长点的出现是现代地球化学发展的趋势。 研究重点的新转移—增强社会功能； 美国国家研究委员会（NRC）出面组织的“固体地球科学的研究现状和研究目的委员会”在其评估报告—《固体地球科学与社会》中固体地球科学的目标是：“了解整个地球系统的过去、现今及未来的行为。这种兴趣已从生命演化的地表环境，到地壳及其流体包层（大气圈和水圈）之间的相互作用，向下扩展到地幔和外核，并一直至内核。…要利用这种认识维持生物圈和人类将继续繁荣下去的环境。”
NRC主席（F. Press）指出，面对这一目标，面对资料开发、废物处理、环境保护、减轻灾害和土地利用的严峻挑战，“我们已进入固体地球科学的一个关键时期，许多专业团体正把他们的研究重点从勘探和开发资源，转移到全球规模和区域范围的环境和社会问题上。”
To develop the scope of geochemistry • In microcosmic，to get information from particulate, minor and micro structure； • In macro，向时、空及时－空组构延拓； • In time, including modern and Quaternary，trace back to early earth，甚至宇宙“大爆炸”、星云凝聚之初， • In space, from continent to ocean and astrospace 在地球上，则更讲求研究对象所处的构造部位、层次关系；状态上已从静态到动态，不论是元素的分布，还是一个地球化学过程，都要求探讨其演化过程，再把时-空关系和状态组合起来，探讨过程的时-空演化，讨论它的全球变化过程，最终从“整体地球”的观点来看问题。
基础科学与相邻学科成果的引入、结合和渗透，不仅扩大了视野，提高了地球化学理论水平，而且拓宽了研究领域，逐渐完善研究手段，使地球化学进入一个崭新的阶段。基础科学与相邻学科成果的引入、结合和渗透，不仅扩大了视野，提高了地球化学理论水平，而且拓宽了研究领域，逐渐完善研究手段，使地球化学进入一个崭新的阶段。 地球化学的若干重要生长点： Organic geochemistry；ore deposit geochemistry；biogeochemistry；Element geochemistry ；isotope geochemistry；Environmental geochemistry ；Quaternary geochemistry ；sedimentary geochemistry ；marine geochemistry ；Precambrian geochemistry；cosmochemistry；regional geochemistry；rock geochemistry；chemical earth kinetics; thermodynamics and kinetics in geochemistry; experimental geochemistry; gas geochemistry.
Stratagem significance of geochemistry 地球科学重大问题：地球形成演化；板块构造理论（玄武岩年龄与大洋扩张、10Be指示壳幔循环），生物大规模死亡（1979年，阿佛雷兹(W.Alvarez)在K (Cretaceous)—T (Tertiary)界线研究得最好的古比奥附近，研究发现整个K铱的背景非常稳定，0.3×10-9，但在其上覆的T之间1㎝厚的界线粘土中，Ir增加了20倍，达到6.35×10-9。在界线以上1米处的灰岩中又回到背景值。随后，他又分析了丹麦的样品，发现界线粘土铱比背景值高出160倍,氧同位素指示海水温度升高10度。 当然也有人指出，生物大规模死亡与地球上大规模的火山喷发有关。
References of geochemistry 涂光炽等，1984，地球化学，科学出版社。 自然科学基金委员会，1993，地球化学。 涂光炽等，1998，高等地球化学，科学出版社。 Three outstanding books are classic works in the field of geochemistry, one of which—1924 edition of Clarke’s The Data of Geochemistry. The second is Geochemistry by Rankama and Sahama, pubulished in 1950. The third is Geochemistry by V.M. Goldschmidt. Brian Mason, 1982 Principle of Geochemistry Paul Henderson, 1982 Inorganic Geochemistry
地球化学杂志：Chemie der Erde, 1919, German; геохимия 1956; Geochemica et Cosmochemistry Acta,1950,国际；Geochronigue,1968,France; Geochemistry International, 1964; Chemistry Geology,1966; Journal of Geochemistry,1966, Japan; Organic Geochemistry, 1977, America; Geochemistry，1972，China, in Chinese； Chinese Journal of Geochemistry, 1982;
Biogeochemistry, 1985, Dutch; Global Biogeochemical Cycles,1987;America; Applied Geochemistry, 1986; Journal of Geochemical Exploration, 1972.
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