The history of Vietnamese territory is closely related to the formation of the Earth. There are 3 main stages: -Stage pre-cambri -Stage Co Kien Tao -Stage Tan Kien Tao
Stage pre-cambri • a. Time: This is the oldest, most prolonged period in the history of development of Vietnam, begun 2 billion years ago, ending 540 million years ago. • b. Only in a narrow area on our territory today: ancient platforms such as arches of Chay river, Hoang Lien Son, Ma river, Kon Tum block .... • c. Natural ingredients are very primitive - Atmosphere is very thin, almost no oxygen, only ammonia gas, carbon dioxide, nitrogen, hydrogen. - Waterborne: almost no surface water. - Poor organisms: algae (green algae, red algae), molluscs (jellyfish, sea anemones, sea anemones, snails, snails).
Stage Co Kien Tao • a. Time: Expected in length to 477 million: Từ kỷ Cambri -542 triệu năm đến Kreta -65 million. • b. This is the most volatile period in our country's natural history Many areas are submerged in sea water and elevated through the movement of paint: Caledoni, Hecxini, Indoxini and Kimeri. Strong folding areas: Cham river archipelago, Viet Bac upriver, Kon Tum geomorphology, Northwest ... - Areas of fault, earthquake, strong eruption, forming rocks: granite, andezite, minerals ... c. The landscape of tropical geography in our country has been very developed.
Stage Tan Kien Tao •
This is the last stage in the history of the formation and development of the Vietnamese territory, which continues to this day.
a. Time: This is the shortest period in the history of natural formation and development of our country. • b. Strongly affected by the cyclical movement of the Alps - Himalayas and the global climate change: - Advocate Hymalaya => folding, faulting, magmatic eruption, sedimentation, forming exotic mineral deposits ... c. It is a period of continuous improvement of the natural conditions that make our country look and feel like today: - Raise the terrain => young and active river, ancient hills are raised and expanded. - Form plateau + delta - Expanding the East Sea to create oil and gas tanks. - Evolutionary biologists - human beings appear. - The humid tropical nature has been shown clearly.