The establishment of the model must fully analyze and compare the research data of a large number of similar or similar deposits as the prototype of the model, and at the same time grasp the mutual restriction of key metallogenic factors. The unity of opposites and mutual transformation of these factors is often the key to understand the specific shape, scale and nature differences of the same type of deposits. Practice has proved that there are many prospecting models with global significance, such as porphyry copper deposits and Carlin-type gold deposits, which have been widely used all over the world, and large mines of the same type have been discovered.
There may be several types or groups of ore-controlling structures of the same mineral in the same area. The same type of deposits can occur in different geological environments, and more importantly, there may be new minerals and types different from the known deposits in the work area. Therefore, in the known ore belt, we should not only look for deposits similar to known deposits from known to unknown, but also have innovative ideas and pay attention to those anomalies with different characteristics and different geological environments.
Some researchers like to extend the regional prospecting model to the whole world, which is risky, because many prospecting models only have regional significance and often achieve the most direct and obvious prospecting effect in a tectonic metallogenic belt or metallogenic basin. For example, after American scholars established the model of porphyry copper-molybdenum deposit, geologists tried to find another Clima-type porphyry molybdenum deposit in the vast area of the United States, starting from Alaska in the north, southern Chile in the south and Greenland in the east, but failed. Finally, they returned to the Colorado metallogenic belt where Krimax Molybdenum Mine is located, and discovered two large concealed molybdenum deposits, Redmont and Emmons Mountain.
We should treat the prospecting model with materialism and dialectics instead of metaphysics. A model is a work hypothesis or work experience, not a framework. No two deposits in the world are exactly the same, and it is not certain what kind of deposits there are in this area at the initial stage of prospecting. Therefore, when prospecting in an area, we should not only follow one model, but also consider all relevant models according to the actual situation. When we use a certain prospecting model to predict or locate the target area, we should be psychologically prepared, one should not abuse it, and the other should not be absolute. Even the mature scientific model, once abused and beyond the reasonable scope, will also lead to wrong exploration ideas. There is a famous saying in the international oil industry and even the mining industry: "Oil can usually be found in new areas with old concepts, and oil can also be found in old areas with new concepts. However, it is difficult to find oil in old areas with outdated concepts. " Undoubtedly, this view is correct, which shows that even a fairly mature prospecting model has its limitations and needs to be revised and improved by geologists. This modification and improvement is not a denial of the original model, but a further development of the original model.
The model is generally useful for known types of deposits, but it is difficult to guide the discovery of new types of deposits and unique super-large deposits, so it is necessary to give full play to scientific imagination according to the actual situation in the work process. Through creative thinking, the model is constantly revised to make it gradually close to reality. On the other hand, it really guides the prospecting work and prevents the negative effects of the model. There is no universal prospecting model in the world, and there is no fixed prospecting model. We can't let individual judgments in books bind our thoughts and hands, nor can we regard what we have achieved in practice as a perfect model.
When we pay attention to the particularity of the prospecting model, we can't regard the temporary setback as the failure of the whole exploration plan. In the case of blocked prospecting, geologists are required to make use of the latest observation results and scientific achievements at any time according to detailed theoretical research and analysis of specific geological environment, revise the original ideas, explore new models and further guide prospecting. In this way, several prospecting models can be applied in the exploration of the same area and the same mineral (5- 1 column).
Column 5- 1 New uranium exploration model and breakthrough in athabasca basin.
During the uranium exploration after World War II, a small uranium deposit related to hydrothermal activity was discovered in athabasca Basin. When the upsurge of uranium prospecting rose again in the mid-1960s, France mainly followed the example of West Africa (Gabon, Niger) and the United States to find sedimentary uranium deposits with sandstone as host rocks, and placed the exploration target area on the edge of the basin. Airborne radioactivity survey and finding glacier boulders in abnormal areas have become the main methods, and large uranium deposits such as Lake Kelev and Lake Labeth have been discovered one after another. Through the study of these deposits, it is found that uranium deposits are located on the unconformity surface between Proterozoic graphite-bearing argillaceous deposits and Mesoproterozoic sandstone. Based on the Australian experience in discovering the East Aligat uranium deposit, the unconformity uranium prospecting model is formally put forward, which provides guidance for further prospecting in athabasca Basin.
What needs to be pointed out in particular is that in many cases, geological science is an observation science, field investigation and research is the basis of all geological work, and all geological facts are recorded in rocks and structures. Therefore, when describing geological phenomena, we should truthfully record what we have seen, without any personal opinions, and be detailed, such as the number, length and width of veinlets, the change of alteration intensity and the relationship between altered minerals, which are often closely related to mineralization. Therefore, we should do a good job in field work and collect field data comprehensively and truly. Only in this way can we objectively establish a prospecting model and evaluate a certain deposit.