Dinosaur fossils can be well preserved

Hard parts like bones and teeth in dinosaurs are made of minerals. Minerals tend to break down and recrystallize underground, becoming harder in a process known as "petrification." As the sediments above continued to thicken, the remains were buried deeper and deeper, eventually turning into fossils. The surrounding sediments also turned into hard rock. This process is extremely slow.

There are many dangers as petrochemicals return to the surface. During thousands of petrifications, the surrounding rock may bend and deform so that the fossils are squashed. In addition, the high temperature at the bottom of the earth's crust could also melt the fossils. After escaping these disasters, someone has to find the fossil before it separates from the surrounding rock formations, or the fossil will shatter and disappear.

In addition to many fossils preserved in sedimentary rocks, it is possible that fossil footprints on the surface of cooled lava have been preserved. And forever frozen on the ground, such as the permafrost of Siberia, can also preserve fossils very well.

Sedimentary rock is a kind of rock formed by the consolidation of sediments deposited in rivers, seas, basins or land. According to its genesis and material composition, it can be divided into conglomerate, sandstone, mudstone, etc. Because the sand particles that make up sedimentary rocks are so fine that they preserve fossils well, they also contain round stones called nodules. Nodules are formed by chemical changes and are formed because of the presence of fossils.

Water, wind or human activity can cause fossil-bearing rocks to emerge. Erosion cliffs and river banks are good places to look for fossils. Sites where fossils have been exposed due to human activity, usually including quarries, roadsides and construction sites.

Geological maps are often used when looking for burial sites that may contain fossils. Geological maps can show rock types of different types or units of outcrops. Aerial and satellite cameras can also be used in conjunction with geological maps to pinpoint the precise location of outcropping rocks.