Despite being a densely populated and highly developed city, Hong Kong has a rich and fascinating geological heritage, including spectacular landforms, such as the redbeds on Port Island, sedimentary formations in Tung Ping Chau, and jointed rock columns on High Island and the Ninepin Islands.
To enhance public knowledge about Hong Kong's geology and different types of rocks, the Hong Kong Science Museum is holding an exhibition entitled "Hong Kong Geology 360" which will run from today (May 17) to August 16 at the museum lobby. Through the display boards and 28 exhibits, visitors can learn about the geological history of Hong Kong, fold and fault structures, landscapes, minerals, rocks and fossils, and the application of geology in Hong Kong.
"Hong Kong Geology 360" is jointly organised by the Department of Earth Sciences and the Stephen Hui Geological Museum of The University of Hong Kong, the Geotechnical Engineering Office of the Civil Engineering and Development Department, the Geological Society of Hong Kong and the Science Museum. The exhibition aims to give the public an overview of the geological environment in Hong Kong, promote greater interest in earth sciences and raise the awareness of the need to preserve our geological heritage.
Hong Kong and its adjacent area was probably a mountainous region 100 million years ago. Over time, the mountains were levelled by erosion and weathering processes. Rock materials were broken down into sediments, which were transported by wind and water and deposited in bays and along rivers. The current landform of Hong Kong is the combined result of many factors and processes that have operated and interacted with each other continuously. The topography is essentially controlled by tectonic processes that affected the entire region, rock types and geological structures.
Mirs Bay basin on the east and the Pearl River Delta to the west of Hong Kong are both rifted basins formed by extension of the crust. Volcanic rocks, which are generally more resistant to erosion and weathering, form the highest hills in Hong Kong. The less resistant mudstones and schists are located in the low-lying areas in Yuen Long.
Faults and folds are structures produced by deformation of the crust. Subjected to external forces, rocks may bend, break or flow. The deformation of a rock layer depends on several conditions such as its material, temperature, pressure, presence of water and the rate of deformation.
The first fossil discovery in Hong Kong was made in the 1920s by CM Heanley, a physician and amateur geologist. The fossil was an ammonite, a marine animal that lived during the Mesozoic Era. Geologists use fossil records to reconstruct the ancient environments and the history of geological evolution. Fossils can now be found in several rock formations in Hong Kong.
To tie in with the exhibition and to enable the public to learn more about Hong Kong geology, a series of lectures and visits to be conducted in Cantonese have also been organised.
The Science Museum is located at 2 Science Museum Road, Tsim Sha Tsui East, Kowloon. It is open from 1pm to 9pm from Monday to Friday and from 10am to 9pm on Saturdays, Sundays and public holidays. It is closed on Thursdays (except public holidays). Admission for the "Hong Kong Geology 360" exhibition is free.
For further information on the exhibition and related programmes, visit the Science Museum's website at http://hk.science.museum. For enquiries, call 2732 3232.
Ends/Sunday, May 17, 2009
One of the exhibits on display - "Siltstone". Siltstone is a fine-grained sedimentary rock. This piece of siltstone comes from Ping Chau in Mirs Bay. The sedimentary rocks on Ping Chau belong to the youngest rock formation (about 50 million years) in Hong Kong.
One of the exhibits on display -"Granite". Granite is the most common intrusive igneous rock in Hong Kong. It is found in many urban areas, such as the northern shore of Hong Kong Island and Kowloon Peninsula. This piece of granite comes from Wan Chai.
One of the exhibits on display -"Conglomerate". Conglomerate is a coarse-grained sedimentary rock. This piece of conglomerate contains rounded quartz pebbles. It comes from Bluff Head, a headland at the northern tip of Tolo Channel where the oldest rock formation (about 400 million years) in Hong Kong is exposed.
One of the exhibits on display - "Tuff". Tuff is formed from deposition of ash from a volcanic eruption. It is more resistant to weathering than granite, and therefore produces the higher summits in Hong Kong. This piece of tuff comes from Tai Mo Shan, the highest peak in Hong Kong.