Article reprinted from Earth Magazine
July 1, 2022
The 25th anniversary of Hong Kong's return to the motherland
The banks of the Fragrant River are gentle and gentle
Lion Rock under the mountains and rivers splendid
May the Pearl of the Orient be better tomorrow
Buildings under Lion Rock
Hong Kong, on the one hand, the city, on the other side, nature.
Hong Kong, as one of the most densely populated areas in China and even in the world, is always reminiscent of high-rise financial districts, bustling and fashionable shopping streets, but in addition to modern cities, it also has a rich natural landscape, beautiful mountains and rivers, peaks and peaks, birds and flowers, immersive, you can temporarily leave the hustle and bustle of the city, as if you are in a natural secret place.
Comparison of the natural environment of the reserve and the densely populated residential areas
In order to protect its precious natural heritage, Hong Kong has established a nature reserve since the 1970s, officially established the Hong Kong National Geopark in 2009, and joined UNESCO in 2011, becoming the seventh batch of global geoparks in the world and the 26th on the mainland.
In 2015, it was renamed the Uniform Marker adopted by the Hong Kong UNESCO Global Geopark
After more than 40 years of history, Hong Kong has a sound management system and sound facilities, with a total area of more than 440 square kilometers of various types of protected areas, accounting for more than 40% of Hong Kong's land area, and it is rare in the world for a highly developed international metropolis to have such a high proportion of protected areas.
Map of Hong Kong Geopark
Major geological monuments
The Hong Kong UNESCO Global Geopark (Hong Kong Geopark) is located in the eastern to northeastern part of the Hong Kong Special Administrative Region, with a land area of more than 150 square kilometers, and is based on country parks, marine parks and special areas.
Precious geological relics, beautiful island scenery and diverse ecological environment make it a natural geological museum and leisure destination. The Hong Kong Geopark has the world's famous hexagonal columns of acid volcanic rocks, typical rich sedimentary strata, and a variety of coastal landforms. According to the main rock species and geomorphological characteristics, it is divided into the Northeast New Territories Sedimentary Rock Park and the Sai Kung Volcanic Rock Park, and the geological characteristics of each scenic spot are unique and the geological resources are extremely rich.
The New Territories Northeast Sedimentary Rock Park, including Dongping Chau, Yin Chau Tong, Chi Mun and Chi Chau Wong Kok Tsui Scenic Area, is characterized by Paleozoic Devonian, Permian, Mesozoic Jurassic, Cretaceous to Cenozoic Paleogene strata, paleontology, sedimentary rocks and tectonic geological remains, exposing a variety of sedimentary rocks and paleontological fossils formed over more than 400 million years, showing Hong Kong's complete sedimentary strata, faults, folds and soft sediment deformation and other geological structures with excellent development, which can be called a typical outdoor sediment geology classroom.
Take a boat ride along the coastline of the northeast New Territories and dig deeper into the area to see the sights everywhere. The oldest rock in Hong Kong can be found in wong Chuk Kok Tsui and the northern shore of the Chimen Strait, formed in the Devonian Period about 400 million years ago, dominated by sandstone and conglomerate, and fossils of paleontology such as fish and bivalves have been found. From the sea, the original horizontal rock formations are squeezed into an almost vertical form, like a piece of red and white "pork belly".
Desponsian stratigraphic profile of Huangzhu Kok Tsui
Follow the coastline to the easternmost DongPing Chau, where the youngest rock in Hong Kong can be found, about 55 million years old, and the relatively well-preserved Cenozoic lacustrine sedimentary rock formations - siltstone, rock layers are stacked on top of each other, displayed between the sea and the sky, looking like a "mille-feuille cake" from a distance.
Thin layers of siltstone are formed by the regular deposition and consolidation of very fine sediments in saltwater lakes, containing large amounts of salt minerals, reflecting the climate change that alternated between semi-arid and relative humidity at that time. The rock formations have well preserved sedimentary structures such as wave marks, parallel stratigraphy, rhythmic stratigraphy, mud cracks, and rain marks, and also contain a large number of plant detritus fossils and insect fossils. These sedimentary rocks form thin, sloping layers that are jointed and weathered to create a variety of coastal landforms.
Dongping chau siltstone formation
"More stone"
There is also a very interesting attraction in the Northeast New Territories Sedimentary Rock Park, that is, yin chau tong in the northwest, which has a unique geographical environment, surrounded by mountains as a barrier, calm wind and waves, is a quiet paradise with no dispute with the world, the first time I visited Yin Chau Tong, I was surprised by the completely different atmosphere and the sense of tranquility and serenity, making it difficult to believe that I was in Hong Kong.
The geomorphological characteristics of Yinzhou Tang are reminiscent of the "Four Treasures of The Study Room", which is vividly known as the "Six Treasures of Yintang", the seal of Yinzhou, the umbrella of Huangpao Mountain, the brush of Baisha Tuttsui, the pen holder of Beacon Island, the thick ink of stone rows near Yinzhou, and the smooth sea water like paper.
Yinzhou Pond (stone row represents thick ink)
Left: Yinzhou (representing the seal), right: Huang baoshan (representing Luo Umbrella)
Beacon Island (stands for Beacon)
Sand Tsui (stands for brush)
Sai Kung Volcanic Rock Park, with the longest coastline in Hong Kong and the largest number of islands, has developed hexagonal columnar joints of acidic volcanic rocks rarely seen in the world. There was a massive volcanic eruption 140 million years ago, forming a large area of columnar joints during volcanic activity, the Grain Ship Bay Formation. The volcanic rock column covers an area of more than 100 square kilometers, the height of the exposed ground is 100 meters, the total thickness is more than 400 meters, the diameter of the stone pillar is about 1.2 meters on average, and the thickest can reach 3 meters, coupled with the rich and diverse coastal landforms, it has become the most representative geological relics of Hong Kong.
Most of the world's columnar joints generally develop in dark gray basalts with low siliceous content, such as the famous World Natural Heritage Giant's located in Northern Ireland, England, while the columnar joints in Hong Kong are rarely developed in light-colored rhyolite volcanic rocks with a silica content of up to 76%, and their scale and lithology are rare in the world.
The sea cliffs of Flower Hill in Grain Ship Bay are covered with neat columnar joints
The Hong Kong Geopark logo features columnar joints as the main design element
The East Dam of Bangi Reservoir is the best place to admire the columnar joints up close. Stroll along the geological trails of Bangi Reservoir and admire these world-class hexagonal rock columns and typical geological formations up close, as if going back in time, we can personally feel the earth's earth's earth over the past 100 million years. S-shaped twisted rock columns can also be seen in Dongba, which were still in a semi-plastic state 140 million years ago, and were slightly deformed due to external forces, forming a unique S-shape.
The East Dam of Bangi Reservoir
The place where the rock column bends is the most vulnerable place, and under the geological action, the rock column is cracked along here, and the underground magma enters along the fissure and pours into the stone pillar, forming a landscape of iconic geological relics in the Hong Kong Geopark.
S-shaped curved rock column
In addition to the acid volcanic rock hexagonal columns, the island of Qiao Tsui Chau in the Sai Kung area also has a variety of volcanic rocks that formed earlier than the hexagonal columns.
Bridge Tsui Chau
The coast of the sandbar at the western end of the island is covered with gravel, due to the rising and falling tides, the gravel is sometimes soaked in the water, sometimes exposed to the water in the sun, strong thermal expansion and contraction and a variety of weathering and erosion effects, resulting in a unique network cracked appearance on the surface of the boulder, which is loved by tourists because of the authentic food "pineapple bun" that looks like Hong Kong.
The surface is cracked with quartz dichocal boulders
Both parks can find a variety of coastal landforms, becoming a beautiful landscape of the Hong Kong Geopark. As sea levels rise, uplifting peaks are submerged and turned into numerous islands, and erosion and sedimentation further shape the long coastline, forming a variety of erosion and sedimentary landforms under the long geological action of internal and external forces, such as sea erosion arches, sea erosion columns, sea erosion platforms, sand mouths, island sandbars and sand beaches.
Sea erosion arch located in Hengzhou
Located on the large slippery surface of the Guozhou Islands
Big Wave Bay
One of the four bays of the Great Wave - West Bay
Biodiversity
In addition to the complex and diverse geological landscape, it is also home to a wide variety of wildlife.
Located on the coast of South China, Hong Kong has a diverse ecological environment and is on the East Asia-Australasia bird migration route, and many migratory birds come to Hong Kong in winter. It is home to one-third of All China's bird species, and nearly 500 species of birds can be seen at different times and places throughout the year.
White-bellied sea eagle
"Seeing the flat boat swaying, Qianjun first makes water and cloud medium", the Geopark is full of free-flying egrets, and you can also find a variety of terns and Hong Kong's largest carving, the white-bellied sea eagle, which visits Hong Kong every summer and thrives here.
tern
In addition to birds, dragonflies and butterflies are also common animals in the Geopark, shuttling through the delicate flowers, dancing in wetlands and streams, competing for beauty, making this place more enchanting and beautiful.
Butterfly (the largest butterfly species in Hong Kong)
Blue-fronted sparse-veined dragonfly
If you want to say the most representative wild animal, it is the Lok little tree frog unique to Hong Kong, which has a short body and an adult body length of only 1.5 cm, which is the smallest frog in China, usually living near water sources, perched on the ground or in dead leaf piles.
Lu's little tree frog
Hong Kong's subtropical climate and marine environment are suitable for tropical and temperate animals, so it is rich in marine life, with 1,000 species of fish recorded. The water quality in the eastern part of Hong Kong is good, especially suitable for coral growth, and the Hong Kong Geopark has produced a large coral community with all 84 species of stony corals and 23 species of soft corals in Hong Kong.
madrepore
Soft corals
Historical and cultural heritage
Walk through the Hong Kong Geopark, travel through the centuries of time and space, read historical stories, and explore the humanistic history integrated in this natural heritage, where a unique culture is being nurtured and developed.
Ancestors flourished here as early as the Stone Age, and Neolithic (6,000 years ago) stone tools and ceramics have been found in the Yazhou area. Until the Song Dynasty, the Hong Kong area was sparsely populated, mainly the Li, She, and Yue ethnic groups, and later there were Central Plains people who escaped war and went south to settle in the plains of northwest Hong Kong. The northeast New Territories and Sai Kung areas covered by the Geopark are sparsely populated in the early days due to their remote and remote location due to their mountainous and remote locations.
The Hong Kong Geopark preserves a number of villages founded in the mid-19th century or even the 15th century, mainly fishing villages and Hakka villages. Due to their remote location and most of them located in protected areas, the village buildings have been preserved, and most of the village houses are built of green bricks and mud bricks, and some of them retain agricultural tools that are rarely seen by urban people. Although the permanent population of Ji'ao is less than 50 people, the villagers still strive to maintain traditional life and customs, leaving behind a rich historical and cultural heritage.
Chiao Island (In the 1960s, Chiao Island was a thriving island with about 6,000 fishermen and Hakka residents. ）
The Hou Shan Forest Area, where most Hakka villages in the New Territories are concentrated, is the best-preserved forest area in Hong Kong, and the ancestors of these original Hakka residents mostly moved from all over South China hundreds of years ago, believing that the mountains are the place of life, so most of the villages are built on the mountains. Trees surround the village in a half-moon shape, forming a "feng shui forest", and the villagers believe that this forest can protect the village and bring good luck.
Feng Shui forest can not only protect water and soil, prevent mud and rock flow, as a natural barrier can block the cold and dry northeast monsoon, but also has the function of fire insulation, can slow down the spread of wildfires, dense broad-leaved forests can also regulate the microclimate, improve the living environment. After more than 300 years of protection, it has important humanistic and ecological value.
Feng Shui forest behind Lychee Wo Village
Winding geological landscape
Majestic coastal landscapes
Lush and flourishing forest vegetation
Precious and abundant wildlife
Unique history and culture
Fusion collides here
It has formed a unique Hong Kong Global Geopark
It has also witnessed the vicissitudes of Hong Kong's geological history over the past hundreds of millions of years
Acknowledgements: Information and photos provided by the Hong Kong Agriculture, Fisheries and Conservation Department.
This article was first published in Earth, No. 6, 2020, with abridged and revised image source: Hong Kong Agriculture, Fisheries and Conservation Department
Editor-in-charge: Bian Yueyue
Typography: Yin Lu
Review: Li Wenhui