Who Shaped the Land?
Who Shaped the Land?
The earliest rocks in Hong Kong have approximately 400 million years of history. The geological structure in Hong Kong was more stable back in those days when the rocks were located in the coastal lake district on the edge of the Mainland. Around 160 million years ago in the Jurassic period, Hong Kong had its most active geological movement where volcanos were strewn across the periphery of Hong Kong. 140 million years ago, an ash layer of over four hundred metres thick was deposited by an enormous volcanic eruption. During the cooling period of the ash, internal expansion caused by the volumetric contraction led to dispersion of the entire ash layer, which gave rise to the hexagonal volcanic columns juxtaposed vertically, and this is indeed the uniqueness of volcanic columns in the Hong Kong Geopark.
When people come across with grotesque rocks, they are always amazed by such god-sent creations. However, the shape of every rock is the logical conclusion for geologists. Professor CHAN Lung-sang is the first generation of geological expert born and raised in Hong Kong. He has been engaging in the studies of Geophysics for over forty years. He deduces the influences which different forces have in topological formation, through observation and research. To him, a one-metre thick rock may have ten thousand years of history inscribed in it; an ordinary rock may contain information of terrestrial history. For example, he once found on the rocks of Tung Ping Chau, the evidence of existence of cyanobacteria, an important creature which helps generate oxygen for the Earth
Apart from the hexagonal volcanic columns, many variegated sea caves have been formed by million years of weathering and marine abrasion on the rocky shores in Sai Kung, which have provided an ideal habitat for a multitude of creatures.
In addition, volcanic and diastrophic activities in the past have contributed abundant mineral resources to Hong Kong, which made the mining industry one of the financial mainstays in Hong Kong back in the day. Although the mining industry has passed its heyday, the old mine caves have transformed into a dark and undisturbed ambience - a survival space for the Ranidae family and bats. In Hong Kong, there are fourteen species of bats even if we only take into account those which are troglobites. The mine cave in Lin Ma Hang, Sha Tau Kok, was even zoned as "Site of Special Scientific Interest" (SSSI) after it was shut down in the 90’s.
Jackie, the apprentice of Professor CHAN, has conducted research on Hong Kong mining industry as a geologist. His dream is to revive the old mine caves, so that public can better understand the history of local mining industry. He believes that both public education and topological preservation are indispensable in protecting the prestigious natural landforms in Hong Kong.
Producer: Hung Ka-wing, Joseph
Assistant Producer: Chan Sin-yan, Cindy