"August 18th Tide, the world is full of wonders", referring to relevant materials, this paper talks about the reasons for the emergence of Qiantang River Tide. In 2004, 10, 1, every August 18th of the

"August 18th Tide, the world is full of wonders", referring to relevant materials, this paper talks about the reasons for the emergence of Qiantang River Tide. In 2004, 10, 1, every August 18th of the lunar calendar. The reasons for the spring tide in Qiantang River are as follows: the mouth of Qiantang River is trumpet-shaped. On the south bank of Qiantang River, nearly 500,000 mu of land was reclaimed to the east of Zheshan Mountain, which blocked the estuary like a peninsula, making the Qiantang River from Zheshan Mountain to the outer 12 sections look like a big bottle. The tide is easy to enter but difficult to retreat. The width of the outer mouth of Hangzhou Bay is 100 km, which is only a few kilometers to the outer 12 section. The riverbed in the eastern part of the estuary suddenly rises and the beach is shallow. Due to the rapid shrinkage of the river surface, the tide can't rise evenly, so the back waves push the front waves, and the front waves don't run fast, and the back waves catch up with each other and stack up layer by layer. Secondly, it is related to more sediment deposited under the Qiantang River. Sediment blocks and rubs the tide, which makes the front slope of the tide steep and gentle, thus forming a wave after wave catching up with the front wave, wave after wave, wave after wave.

On June 18, 2004, 65438+ 10, 1, hundreds of thousands of people came from all over the country to watch the tide. They waited all day, but the tide didn't come because the northwest wind was very strong.

Therefore, the answer is: the Qiantang River spring tide is caused by the trumpet-shaped estuary of Qiantang River. On the south bank of Qiantang River, nearly 500,000 mu of land was reclaimed to the east of Zheshan Mountain, which blocked the estuary like a peninsula, making the Qiantang River from Zheshan Mountain to the outside 12 section look like a bottle with a small belly. The tide is easy to enter but difficult to retreat. The width of the outer mouth of Hangzhou Bay is 100 km, and the width of the outer 12 section is only a few kilometers, and the riverbed in the eastern part of the estuary suddenly rises. Due to the rapid shrinkage of the river surface, the tide can't rise evenly, so the back waves push the front waves, and the front waves don't run fast, and the back waves catch up with each other and stack up layer by layer. Secondly, it is related to more sediment deposited under the Qiantang River. Sediment blocks and rubs the tide, which makes the front slope of the tide steep and gentle, thus forming a wave after wave catching up with the front wave, wave after wave, wave after wave.

On June 18, 2004, 65438+ 10, 1, hundreds of thousands of people came from all over the country to watch the tide. They waited all day, but the tide didn't come because the northwest wind was very strong.