Miaodao Islands

It is composed of 32 islands with a land area of 56 square kilometers, a sea area of 8700 square kilometers and a coastline of 146 kilometers. The main islands are South Island and North Island. The island has beautiful scenery, including Crescent Bay, Jiuzhang cliff and other tourist attractions. Fairyland source scenic spot on Long Island is an AA scenic spot in China. There are Changdao National Bird Nature Reserve, Miaodao islands provincial marine nature reserve and Miaodao islands provincial spotted seal nature reserve on Changdao.

Miaodao Islands

synonym

Miaodao archipelago generally refers to Miaodao archipelago

Miaodao archipelago, also known as "Changshan Archipelago", is the general name of 32 islands under the jurisdiction of Changdao County, Shandong Province. The main islands are: South Changshan Island, North Changshan Island, Daheishan Island, Xiaoheishan Island, Miaodao Island (commonly known as the South five islands) in the South and Duji Island, Daqin Island, Xiaoqin Island, nanhuangcheng Island, beihuangcheng Island (commonly known as the North five islands) in the north and other uninhabited islands. Among them: the largest island is south Changshan Island, which is the residence of Changdao County Government. The smallest island is xiaogaoshan island. The longest distance between North and South Islands is 56.4 km, and the widest distance between East and West islands is 30.8 km. The total length of the coastline is 146.14 kilometers, and the total area of the island and land is 53.17 square kilometers.

Miyuri archipelago is located at the intersection of yellow and Bohai two seas in the Bohai Strait. The north meets the old fellow iron mountain in Liaoning Province, and the south meets Penglai county. Militarily, it is the "throat" of Bohai Sea and the "gateway" of Beijing and Tianjin. Economically, it is the main fishery base and new tourist destination in Shandong Province. Sea cucumber, abalone, sea urchin and other marine treasures enjoy high reputation at home and abroad. They are named as "the hometown of abalone, scallop and kelp in China". They are important export bases of marine treasures in China. It is a national key tourist attraction, migratory bird reserve and island Geopark.

Name evolution

Miaodao archipelago, known as the Qing Dynasty. The name of Miaodao originates from the Temple Island in the south of the archipelago, on which there is the Xianying palace built in the Song Dynasty. Before the reign of Emperor Guangxu of the Qing Dynasty, Changshan Island, Miao Island, Daheishan Island, Xiaoheishan Island, Tuoji Island, Daqin Island, Xiaoqin island and beihuangcheng Island were inhabited, so they were called eight Changshan Islands. During the reign of Emperor Guangxu of the Qing Dynasty, the whole archipelago was called Miaodao archipelago, which was later renamed Miaodao archipelago. During the first liberation, it was called Changshan island. During the period when the Kuomintang army occupied the island, it was first called Changshan Archipelago (recorded in the annals of Shandong Province · Jianzhi: from September 1947 to August 1949 (Miaodao archipelago) and was occupied by the Kuomintang army. Changshan Archipelago was set up, belonging to Penglai county

）In July 1947, to avoid confusion with the name of Changshan Archipelago in Liaoning Province, it was renamed Donglai archipelago. At the beginning of the people's Republic of China, it was called Changshan island. After the county was established in 1956, it was renamed Changdao. The time of Miaodao archipelago is unknown. Official materials such as Shandong Provincial chronicles, natural geography, Yantai City Chronicles (I) and Changdao County chronicles published around the end of the 20th century, as well as general legal maps, are all marked as Miaodao archipelago.

The appellation of "Changshan Archipelago" is still seen in some media, and its scope is basically the same as that of Miaodao archipelago. There is also the Changshan Archipelago (also known as "Changshan Archipelago", no longer called Changshan Archipelago) to the east of Liaoning Peninsula, which is called "neichangshan Archipelago". These appellations are rarely seen in official media. Also see the appellation of "Miaodao Archipelago", the origin is not clear.

Miaodao, formerly known as Salmonella Island, is a place for prisoners of death penalty. After the song and Yuan Dynasties, the sea water transport rose, surrounded by islands, became a natural harbor, and then gradually prospered. The goddess of the sea temple (Yingxian Palace) on the island. It is said that Miaodao archipelago was called Salmonella island in ancient times, which is incorrect.

In addition, among the 10 inhabited islands in Miaodao islands, the residents of Changshan island are commonly known as the South five islands and the North five islands.

Location context

Miaodao archipelago, including the local residents commonly known as the South five islands, North five islands based on 32 large and small islands. The archipelago is located at the intersection of the Yellow Sea and the Bohai Sea in the Bohai Strait, 120 ° 361-120 ° 56 'e and 37 ° 53' - 38 ° 23 'n. North confronting the old fellow iron mountain in Liaoning Province, south facing Penglai County, Bohai's "throat" and "Beijing and Tianjin" gateway. The total length of the coastline is 146.14 kilometers, and the total area of the island and land is 53.17 square kilometers.

Island distribution

There are 32 islands in Miaodao Archipelago (21 in jianzhizhi, Shandong Provincial Records), which are distributed in the direction of south-south-west to north-north-east. Nanchangshan Island, beichangshan Island, Daheishan Island, Xiaoheishan Island, Miao island in the South and Tuoji Island, Daqin Island, Xiaoqin Island, nanhuangcheng island and beihuangcheng island in the north are inhabited islands, while the rest are uninhabited islands.

The largest island is Nanchangshan Island, with an area of 12.3 square kilometers. The smallest island is xiaogaoshan Island, with an area of 0.0008 square kilometers. The highest island is Gaoshan Island, with an altitude of 202.8 meters; the lowest island is dongzuishi Island, with an altitude of 7.2 meters. The longest distance between North and South Islands is 56.4 km, and the widest distance between East and West islands is 30.8 km.

Island formation

Miaodao archipelago, located in the east of Bohai Sea subsidence zone, is a branch of Changbaishan system and a part of Jiaoliao uplift.

In the late Proterozoic, the islands were not separated from each other, and connected with the north and south land, commonly known as "Jiaoliao shield". During the Yanshanian tectonic movement 140 million years ago and the later Himalayan orogeny, a series of nee, NNW, NNE and NE trending faults occurred successively. From then on, the ancient continental block fault depression separated into the embryonic form of islands, thus forming the Bohai Strait.

Since the late Pleistocene, there have been three major transgressions and regressions, and the islands have experienced successive "carving". After the "Lushan glacial period" about 100000 years ago, the climate entered the warm stage of interglacial period. The glaciers melted, the ocean water increased, and the sea water rose, exceeding the Shanya gully between Jiaozhou and Liaohe, flowing to the ancient Bohai lake and North China Plain, and even drowning Cangzhou (historically known as "Cangzhou transgression"). Since then, the fractured Jiaoliao shield has become an island in the sea.

The surging sea water occupied the Bohai Sea for tens of thousands of years. From the "Dali ice age" about 70000 years ago, the land was suddenly cold and ice and snow were confined. Most of the land precipitation from seawater evaporation could not flow back to the sea. The sea water gradually withdrew from the Bohai Basin. In the past, the sea floor became land, and the Miaodao islands were connected with the Qianli plain and became hills on the land.

The cold climate began to warm 45000 years ago, and transgression occurred again. The scale of this transgression is larger than that of the previous one, extending to the territory of Xianxian County in Hebei Province (historically known as "Xianxian transgression") and leaving traces of this transgression along the coast of Bohai Sea. For example, the sea erosion cave left by this transgression is located at an altitude of 100 meters in Shedao, Liaoning Province. At present, Beigou commune in Penglai county is about 4 kilometers away from the coast on the north slope of the west of the Yingkou of beilinyuan. It still has intact quartzite sea erosion topography and 5-6 meters high sea erosion column. At the altitude of 60-70 meters in Miaodao archipelago, there are traces of sea erosion. After the Xianxian transgression, it still tends to regress.

In the Holocene, the climate entered the warm period after the ice age. A lot of glaciers melt and the sea level rises again. During the ice age, the Bohai Sea, once a swamp grassland, became a vast sea again. The Bohai Coast has been pushed into Huanghua, Jinghai and Tianjin (historically known as "Huangqi transgression"). The sea erosion line reaches Jiuzhang cliff of beichangshan island and "Banpo" of Beizhuang of Daheishan Island (both about 15 meters above the present sea level). After this transgression, large-scale regression began. It was not until 1300 years ago (early Tang Dynasty) that the coastline of the island was slightly higher than that of the modern island. The whole archipelago is still in a slight change of "rising from south to North".

geology

Dudao in Changdao County is adjacent to Liaodong uplift in the north and Jiaodong uplift in the south. It is adjacent to the Bohai depression in the West. The exposed strata are Penglai group of Upper Proterozoic, which is a set of low metamorphic rock series. The island land structure is simple, the strata are mostly monoclinic, the fault scale is small, and the magmatic activity is weak.

stratum

It is the Penglai group of the Upper Proterozoic. Baoshankou formation: the lower part is dominated by sericite phyllite, intercalated with greisen, Zitie feldspar quartzite and feldspar quartzite. The upper part is mainly composed of purple and cyan gray slate intercalated with feldspar quartzite and quartzite. It is mainly distributed in DAZHUSHAN, Xiaozhushan, Cheyou, Duzi, Gaoshan, Houji and Duji islands. Fuzikuang formation: the lower part is mainly interbedded with greenish gray and purple slate and quartzite. The upper part is interbedded with quartzite and slate, which is thick. Distributed in Daqin, Xiaoqin, beihuangcheng, nanhuangcheng, Nanchangshan, beichangshan, Daheishan and Xiaoheishan islands.

Upper Tertiary: Basalt erupted in two stages. In the lower part, the stomatal structure is well developed, and there are phenocrysts locally, which are ILLITIZATION olivine. The upper part is dark gray black, slightly dense and hard basalt with occasional phenocrysts, which are pyroxene and edinized olivine. It is distributed in the west of Daheishan island and the West Valley of Beizhuang village, with a maximum thickness of 70m. Pillow structure and volcanic bomb can be seen in the field, and unconformity covers the "Penglai group" strata.

QUATERNARY: most of the islands are distributed, especially in Daqin Island, Tuoji Island, Daheishan island and Nanchangshan Island, which are gradually thickened from south to north. The quaternary system can be divided into eluvium, Deluvial diluvium and marine deposit according to its genesis.

The eluvium is composed of gravel and brownish red clay

Chinese PinYin : Miao Dao Lie Dao