In memory of Mr. Tu Guangchi, the master of mineral deposit science

(China Geo University, Beijing)

Mr. Tu Guangchi is an outstanding geologist, deposit scientist and geochemist. He loves the motherland, earth science and geology and minerals, and has made great contributions to the development of earth science, the research of mineral resources and the cultivation of geological talents in China all his life. As a post-student of mineral deposit science, I am fortunate to have more contact with Mr. Tu and have the opportunity to directly accept his teachings. I deeply feel that he is the most respected mentor in my life. Now, I just want to talk about some understanding and learning experience about Mr. Wang's contribution to mineral deposit science.

Mr. Tu has been engaged in geological work for more than 60 years, with profound academic foundation and strategic vision. In his research field, he can put forward cutting-edge research topics and ideas according to the needs of national construction and the development trend of geosciences in various development stages, and participate in and organize their implementation, which has played a pioneering and leading role. In the early 1950s, he returned from studying in the United States and taught in Tsinghua University. First, he teaches the new subject of geochemistry at home. 65438-0955 participated in organizing and leading the comprehensive geological survey of Qilian Mountain, divided the tectonic lithofacies zones, and put forward the prospecting direction. In 1960s, uranium geology was studied, and the mechanism of uranium mineralization was put forward, which reasonably explained the geological and metallogenic process of most uranium deposits in China. In 1970s and 1980s, he systematically studied granite and its mineralization in South China, and put forward a relatively complete theoretical system of diagenesis and mineralization. In the national battle for rich iron ore in 1970s, he summarized the metallogenic characteristics of China iron ore, and pointedly pointed out that the geological conditions in China were not suitable for the formation and preservation of large-scale weathered crust-type rich iron ore from the particularity of geological historical evolution in China, which was confirmed by later prospecting practice.

In the 1980s, he organized and led a systematic study on the geology and geochemistry of stratabound deposits, deeply discussed the metallogenic characteristics of lead, zinc, uranium, mercury, antimony and iron deposits in China, expounded the geological and geochemical characteristics, causes and classification of stratabound deposits, and published the monograph Geochemistry of Stratbound Deposits in China, which is a classic study of stratabound deposits in China, representing the latest achievements and frontier direction of mineral deposit science and geochemistry at that time. During the 1980s, he also made a comprehensive study of gold geology in China, and put forward a new gold classification scheme, which was widely cited. Over the years, according to the geological characteristics of southwest China, he has opened up the research fields of low-temperature geochemistry and low-temperature mineralization, and his academic achievements rank among the top in the world. He also deeply studied the regional metallogenic regularity in northern Xinjiang, summarized the deposit types and metallogenic mechanism of gold, silver and antimony, and raised the metallogenic research in this area to a new level. At the beginning of 1990s, he had a deep insight into the development trend of international mineral deposits, and organized and led the research on super-large mineral deposits in China in time, including the metallogenic environment, ore-controlling factors, metallogenic mechanism, analysis of typical mineral deposits, etc., which lasted for more than 10 years, which not only made China's research achievements in this field rank among the top in the world, but also effectively guided the prospecting work of large-super-large mineral deposits. Entering the 2 1 century, he is over 80 years old and often goes deep into mine site inspection and guidance. His efforts and rigorous and realistic spirit are touching. In his later years, he accumulated many years of experience, put forward the research direction of comparative deposit science, and edited the classic book History of Geoscience Thought with long-term guiding significance.

Mr. Tu has a wide range of academic research fields. Besides being the founder and leader of geochemistry, he mainly studies mineral deposits: gold, silver, iron, copper, lead, zinc, mercury, antimony, uranium, rare earth, rare and dispersed elements, etc. A new understanding of deposit characteristics and metallogenic mechanism is put forward. In terms of deposit types, in addition to the traditional endogenous, exogenous and metamorphic deposits, he also proposed a new category of "reformed deposits", which extended the three-point method to the four-point method, which was supported and cited by the majority of peers. According to the characteristics of geological mineralization in China, he put forward the concept of polygenic deposits and developed the classification of deposits. In the aspect of mineralization, he pointed out the diversity and complexity of mineralization, and emphasized the importance of superimposed and reformed mineralization, which was confirmed by many superimposed and reformed deposits discovered later, and is now considered as a feature of regional mineralization in China. In mineral petrology, he studied granite, alkali-rich intrusive rocks, dark rocks, various metal minerals, mica, chlorite and sulfate minerals. He is very concerned about the genetic relationship between metal mines and oil and gas reservoirs, and proposes to pay attention to the study of this neglected topic. As a master geologist, he knows the history and present situation of mineral deposit science like the back of his hand, and clearly observes its trend. He has written many articles on the progress and development trend of sedimentary science research, which has helped relevant experts to establish a historical understanding of this subject. He has a scientific thinking method and is good at applying materialist dialectics to complex metallogenic research. His exposition on deposit research methods is very incisive, from which I get a lot of inspiration, which enables me to carry out deposit research better.

Mr. Tu is good at starting from the geological reality of China, grasping key scientific issues, making in-depth research and achieving internationally influential results. For example, his theoretical viewpoints on polygenetic deposits, superimposed mineralization, reformed mineralization, low-temperature geochemistry and dispersed element mineralization are all based on his profound understanding of China's complex continental structure and multi-stage evolution history. This shows his superb ability to combine theory with practice, as well as the ability to combine micro-investigation with macro-grasp. The enlightenment he gave us is that China has a vast territory, rich natural resources and a special continental structure and evolution history. There are still many new problems in China's resources and environmental science that need to be studied, and we need to dig deeply, explore seriously and make achievements of world significance.

Teacher Tu is rigorous, realistic and down-to-earth. His love and persistent spirit for field geological work are touching. I remember during 1994 and 10, my husband and I visited the metal deposits in Western Australia. The trip is very tight, and the car bumps for a few days after a long journey, basically 1 ~ 2 days to see 1 mine. At that time, Mr. Tu was over 70 years old, had major surgery and was weak. Everyone is worried about his health. But he was in high spirits and talked endlessly. I just arrived in Perth the morning before and went to see a laterite-type aluminum mine in the afternoon. The next morning, I visited a gold mine 400 kilometers away. In the whole process, he has been carefully observing the outcrops and profiles of rocks and minerals, asking questions and thinking deeply. His professionalism and hard work and plain living style have deeply educated us. I admire his sensitivity to new things and his ability to grasp key issues.

Mr. Tu attaches great importance to international geoscience communication. With his rich study and research experience in the United States and the Soviet Union, he has a global perspective on the study of mineral deposits, absorbed the scientific achievements of the American and European schools and the Soviet Union school, and made tests, improvements and innovations from the reality of China's geology and mineral resources. He is far-sighted and often puts forward new research directions and problems with overall significance to us. He introduced the research progress of geochemistry and mineral deposit science in China at many international academic conferences, which expanded the influence of geologists in China. I remember that at the 30th International Geological Congress held in Beijing from 65438 to 0996, Mr. Tu gave a speech on the formation process of the rare earth Fe-Nb deposit in Baiyun Obo, which was widely praised by scholars at home and abroad.

He is meticulous in scientific problems, well-founded, and strictly distinguishes between conjecture, inference and fact. He is proficient in materialist dialectics, good at dialectical thinking, and is adept at using complex mineral deposit problems. For example, his understanding of the genesis of mineral deposits is often one-sided. According to many years' experience, Mr. Tu put forward that "either this or that" and "either this or that" coexist, which is helpful to explain the relationship between different mineralization and the complex and changeable mineralization phenomenon. Teacher Tu is full of wisdom. He is good at grasping the key points and keys. His papers and reports are very concise, and his arguments are rigorous, novel and profound, which is refreshing and beneficial. I still remember the touching scenes in which his speeches were warmly welcomed.

Mr. Tu has lofty ideals, high sense of responsibility and deep feelings for geological science. He has been down-to-earth and persistent for decades, devoted his life to exploring geological mysteries, and made landmark contributions to improving the research level of mineral deposits in China and gradually going to the world. He is a master of deposit science and the main academic leader of deposit science in China in the second half of the 20th century. Under the new situation, he developed the discipline of mineral deposit science and trained a group of young scholars and scientific and technological backbones. His academic contributions and predecessors' demeanor are well-known in the geological science field, which deserves our lifelong memory and serious study. Let us forge ahead courageously along the road pioneered by the older generation of scientists such as Mr. Tu, and make new contributions to the breakthrough of mineral deposit science and geochemistry, and to solving China's mineral resources and environmental problems.