In the mid of 1940's, the Chinese geological survey people supported by the Guomingtang Government made a small geological survey and drilled three holes with Mr. Morrisson, an American expert, of which only Hole No.1 was drilled down to the designed depth and Holes No.2 and No.3 failed because their drillings met solution caverns.

A great many geological surveys had been made more than 40 years before the location of the dam site of the Three Gorges Project since the mid of 1950's after the founding of People's Republic of China. The Chinese people had completed quantities of work and had taken various methods for the geological survey for the selection of the dam site of the Three Gorges Project before the construction of the dam of the Three Gorges Project as no one had done by then in the construction of the water resources projects all over the world as follows.
1. Regional and Reservoir-Region Geological Mapping/ Plotting
   The Chinese experts had drawn 1:500,000 and 1:2000 scale geological maps to cover the area of 24,000 km2; and they had drawn 1:5000~1:1000 scale geological maps for the Sandouping Dam Site to cover the area of 25 km2.
2. Small Bore Drilling
   The Chinese engineers and workers had drilled small bores of 357,000 m, of which they had drilled small bores of 136,000 m.
3. Drilling Tunnels
   The Chinese engineers and workers had drilled adits of 8,373 m and shafts of 1181 m.
4. Various Physical Surveys
   The Chinese experts had made more than 15,000 locations for the reliable geological surveys.
5. Rock Mechanism Tests
   The Chinese experts had made more than 17,700 tests of rock mechanism.
In addition, the Chinese experts had adopted the techniques little used in other water resources projects, such as the air physical surveys at the area for the construction of the Three Gorges Project and the special air remote sensing flights including those of colorful infrared ray filming, black-white air filming and radar scanning. To supervise the seismic phenomena, the Chinese experts, engineers and workers had built up 7 earthquake precipitation stations and had supervised the seismic phenomena more than 30 years since 1959 before the construction of the dam of the Three Gorges Project. It is unprecedented in the history of the construction of the water resources projects all over the world that the Chinese experts, engineers and workers:
1. had long surveyed the seismic phenomena before the construction of the dam of the Three Gorges Project;
2. had made the site investigations and analysis of the great collapses and landslides of the main Yangtze River, especially those of the river length within the reservoir region;
3. had made the modeling tests and calculations of the surges caused by the landslides into the Yangtze River;
4. had set up the form-variation supervision networks on the particular sites for landslide/ fracture;
5. had used the state-standard precision equipment of the second class to supervise the geological variation before the dam and reservoir.

Large quantities of work had been done for geological survey before the selection of the dam site of the Three Gorges Project. The Chinese people had been concerned with the geological surveys for the selection of the dam location of the Three Gorges Project. Dozens of years in the geological surveys of the region for the selection of the dam of the Three Gorges Project had brought the Chinese experts, engineers and workers the achievements in the correct selection of the dam site of the Three Gorges Project, which had made their conclusion authorized. More than 40 academies, universities and construction organizations have joined and have closely cooperated in the geological surveys of the dam sites of the Three Gorges Project, such as the departments of geology and geography of the Beijing University, the Nanjing University and the Zhongshan University, and the Beijing Geology University, the Changchun Geology University, the Chengdu Geology University and the Xi'an Geology University, and the Institute of Earth Physics, the Institute of Geology and the Institute of Geography of the Chinese Science Academy, and the related organizations/ administrations of Both Hubei and Sichuan Provinces, and the related geological administrations of the State Government. The State Science Commission have organized the large cooperations in the scientific studies and researches of the 1950s and the 1980s in the geological survey of the dam sites for the Three Gorges Project. The large scientific group organized in the 1950s was then composed of the most famous experts of geology all over China. It might be concluded that all the Chinese experts of geology at the age of 65 and above have almost joined the geological surveys of the dam sites for the Three Gorges Project.