A key survey in Shanxi province in northern China identified nationally and internationally important fossil sites, according to local officials. 

Officials said the Demonstration Survey of Paleontological Fossil Origins along the Yellow River in Shanxi Province -- organized and implemented by the Shanxi Provincial Geological Relics Protection Center -- was recently evaluated.

They said it passed an acceptance inspection by experts from the Environmental Monitoring Institute of the China Geological Survey and won an excellent grade.

According to the plans, the scope of the 2019 survey included Yuncheng and Linfen cities, covering an area of 34,508 square kilometers, accounting for 22 percent of the province's land area.

During the implementation of the project, 21 fossils sites in the two cities were identified, including two world-level and nine national-level sites, officials said. 

They added that the survey was of great value for studying paleontology in the region.