Dec 09, 2010|
At first, Hong Kong was dry land, with a few rivers crisscrossing the arid landscape. A few hundred million years later, the terra firma on which we now stand morphed into a shallow, swampy sea. Fast-forward a bit more, and violent volcanoes spewed lava and rock everywhere. A desert followed—and, finally, the mountainous coastal environment we know today.
For geologist Bernie Owen, Hong Kong is paradise. A professor at Hong Kong Baptist University, he has devoted his life to studying rocks, from the sands of the beaches to the boulders of mountains. For Owen, it’s a way to understand the reason this place looks as stunning as it does.
“Geology and landscape are much the same thing, once you start reading it,” he says. “There’s a pattern to Hong Kong. Here in this landscape, we have hundreds of millions of years to play with.”
And play we did. Once a year, Hong Kong’s Royal Geographical Society taps Owen to share his expertise on a day-long boat tour; this year, the outing was in the far northeastern New Territories. The trip is usually oversubscribed, with a long waiting list. But on a gorgeously clear December Saturday, I was lucky enough to tag along with a couple dozen Jack Wolfskin-clad would-be explorers.
We set sail from Ma Liu Shui, quickly leaving blocky residential towers behind in favor of the open sea. Into the microphone Owen yells above the wind: “If we did this
journey 8,000 years ago, you’d just be going along a river!” The adventurers chuckle, and then resume the position behind their telephoto lenses.
After passing the Plover Cove reservoir, one of Hong Kong’s main water sources, we dock at Lai Chi Chong, located in a northern cove of lush Sai Kung West Country Park. Chock-full of stripy sedimentary rocks, the picturesque beach is clear evidence that this area was once an active volcanic lake. Some of the strata—created when moving water laid down layer after layer of pebbles, gravel and sand—became beautifully twisted and jagged when movements of the earth’s crust interrupted the normal deposit process before the sediments had hardened. “It’s a visual earthquake,” says Owen. “You can see the earthquake in the rock.”
“The rocks I’m standing on are 142 million years old,” Owen intones dramatically, explaining the source of the vivid colors: feldspar layers weather to become white; and the reddish bands are iron that has essentially rusted in our hot, humid climate. In parts, quartz has infiltrated cracks, leaving an artistic vein-like web.
But just down the beach, rocks look completely different. Deep grey and striated, these clay, silt and mud stones originated from the depths of the volcanic lake, where there wasn’t much oxygen. And around the corner, massive boulders dot the shoreline, the result of a landslide.
It’s not all fun and fleece jackets. Thomas Bauer, an assistant professor of tourism management at Hong Kong Polytechnic University and a member of the Royal Geographical Society’s executive committee, tsks as we spy mounds of garbage heaped up along the beach. Shaking his head, he laments the fact that the government promotes Hong Kong’s natural beauty to tourists—but at the same time fails to keep it clean. We fill up bags of trash and file back onto the boat.
Next stop: Port Island, where red sandstone rocks slope at a steep angle, giving geologists reason to believe that Hong Kong was chock-a-block with sand dunes 100 million years ago. Based on a particular layer snaking through a cliff, Owen can tell that there was once a river snaking through the desert. More importantly, this is where we anchor to inhale lunch and down a few beers.
We cut westward through choppy waters and make a beeline for Bluff Head, where the oldest rocks in Hong Kong, all folded and tilted so they’re almost vertical, have hung out for about 400 million years. After a drive-by we continue through Double Haven. Nearby Double Island is known for its textbook thrust faults, in which older rocks are pushed up above newer ones, upsetting the natural order. We motor past so-called sombrero islands, larger chunks of rock that have been worn down all around the perimeter by typhoons and destructive salt crystals. They are not long for this world, though, given the weather’s continually harsh lashings.
Owen doesn’t just have his nose to the ground—he is a font of knowledge of all things environmental: where the best coral is; why the famed pink dolphins only swim in certain spots; where you used to be able to mine lead, iron, graphite, tungsten and silver across the SAR. There’s even a little drama. He has run-ins with massive snakes about once every six weeks, and has braved remote outposts such as Kenya and Malawi for research. He’s written guides to the Geopark, and penned a detailed account of the different geological and topographic points of interest that can be seen along each stage of the 100-kilometer MacLehose Trail. There’s human history among the geologic history, too. In a quiet nook near Bluff Head called Governor’s Beach, he saw Chris Patten, the last British governor of Hong Kong, leaving the lagoon. If he didn’t live here, he tells me, he’d be somewhere like Botswana.
Near the Chinese shore, the horizon turns hazy. We dock once more—this time at Ap Chau, a tiny island ringed by a rocky beach. Its main attraction: a couple of flats inhabited by wrinkled old men. Well, there are also rugged cliffs, with their component rocks jutting out at all angles. They accumulated here 60 to 70 million years ago, when the spot was at the base of a mountain range from which large angular stones fell. Meanwhile, modern-day waves have dug out a picturesque arch in a layered cliff. But in this environment, nothing is permanent. Owen says erosion will win out soon, causing the arch to collapse.
In Hong Kong, old buildings get torn down and new ones spring up in what seems like days; construction is omnipresent. Such is the transience, too, of Hong Kong’s geologic environment—it just changes more slowly. Eight thousand years ago, the waters our boat traverses were replaced by a rainforest on a hilltop; 18,000 years ago there was no water to be found at all. (You had to walk 100 kilometers south of present-day Hong Kong Island just to get to the beach.)
“I reconstruct history, being a detective from clues in the sediments,” Owen explains. “It’s a series of things you have to think about in order to understand the landscape. All just to explain one boulder on the beach.”
It’s hard to access these spots—you basically have to charter a boat—but here are some organizations that offer field trips:
Hong Kong Royal Geographical Society, www.rgshk.org.hk
Geological Society of Hong Kong, www.geolsoc.org.hk
Hong Kong Geographical Association, www.hkga.org