Qingdao is located in the south of Shandong Peninsula, east longitude119 30 ′ ~100 ′, north latitude 35 35 ′ ~ 37 09 ′, bordering the Yellow Sea in the east and south, Yantai in the northeast, Weifang in the west and southwest. The total area of the city is 1 1293 square kilometers. Among them, the urban area (Shinan, Shibei, Licang, Laoshan, Qingdao West Coast New District, Chengyang and Jimo Seven Districts) is 5,226 square kilometers, and Jiaozhou, Pingdu and Laixi are 6,067 square kilometers.
Geological landform
Qingdao is a coastal hilly city with high terrain in the east and low terrain in the west, convex in the north and south, and concave in the middle. Among them, mountains account for about 15.5% of the city's total area (the same below), hills account for 2. 1%, plains account for 37.7%, and depressions account for 2 1.7%. Coasts are divided into three basic types, namely, rocky coast alternating with headland, harbor muddy coast and bedrock gravel coast. In shallow waters, there are underwater shoals, modern underwater deltas and marine erosion plains.
The tectonic location is the northeast margin of Jiaonan Uplift and the south-central part of Jiaolai Depression, the secondary structural unit of Neocathaysian Uplift. The whole Paleozoic strata and some Mesozoic strata are missing in the area, but the volcanic rocks of Cretaceous Qingshan Formation are developed and widely exposed. Magmatic rocks are mainly Yuejishan gneiss granite in Proterozoic Jiaonan period, Ai Shan granodiorite and Laoshan granite in late Mesozoic Yanshan period. The urban areas are all located on this granite, and the building foundation conditions are excellent. The regional structure is dominated by fault structures. Since Tertiary, the uplift of fault blocks with relatively stable integrity has dominated this area, and the uplift range is generally small.
mountain range
There are three mountains in Qingdao. The southeast is Laoshan Mountain, which is steep and its main peak is 1 132.7 meters above sea level. It starts from Mrding in the west and ends in Qingdao in the north. In the north is Daze Mountain (736.7m above sea level, which belongs to all the mountains in pingdu city and some peaks in Laixi City). In the south is the Jiaonan Mountain Group, which consists of Dazhu Mountain (486.4m above sea level), Zhuxiao Mountain (724.9m above sea level) and Tiecha Mountain (595. 1m above sea level). There are Fushan Mountain (elevation 384m), Taiping Mountain (elevation 150m), Qingdao Mountain (elevation 128.5m), Signal Mountain (elevation 99m), Fulongshan Mountain (elevation 86m) and Shuishui Mountain (elevation 80.6m).
river
There are 224 rivers in Qingdao, all of which are rain sources in the monsoon region, and most of them are independent streams entering the sea. There are 33 large rivers with a drainage area of 100 square kilometers, which are divided into three major river systems: Dagu River, Beijiaolai River and Binhai River.
Dagu River system includes main stream and tributaries. The main tributaries are Xiaogu River, Guwu River, Liuhao River and Nanjiaolai River. Dagu River is the largest river in the city. It originates from Fushan Mountain in Zhaoyuan City, flows into Qingdao from north to south, passes through Laixi City, pingdu city, Jimo District, jiaozhou city and Chengyang District, and reaches Nanmatou Village in Jiaozhou. The length of the main stream is 179.9 km, and the drainage area is 61310.3 km2 (of which the south Jiaolai river basin is 1500 km2), making it the largest water system in Jiaodong Peninsula. The average annual runoff of Dagu River is 66 1 100 million cubic meters. Before 1970s, this river had strong seasonal runoff, summer flood and sharp increase of annual water volume. After that, except for the flood season, the middle and lower reaches have been cut off.
Beijiaolai river system includes main stream and tributaries. The main tributaries are Zehe River, Wanglonghe River, Xianhe River and Baisha River, with a total drainage area of 19 14.0 square kilometers. Beijiaolai River originates from the northern foot of the watershed in Yaojia Village, Liaolan Town, pingdu city, flows northward along the border between pingdu city and Changyi City, and joins Laizhou Bay in Damiaojia Village, xinhe town, pingdu city. The main stream is 100 km long, with a drainage area of 3978.6 square kilometers. The average annual runoff of rivers is 253 million cubic meters, and the average annual sediment concentration is 0.24 kg/cubic meter.
Coastal rivers refer to rivers that enter the sea alone, and the larger ones are Baisha River, Moshui River, Wang Ge Zhuanghe River, Baima River, Liji River, Zhoutuan River and Yanghe River.