There is no physical container at the published coordinates. This is an EarthCache. To find this cache you must visit GZ and the second waypoint, make some observations, and send your answers to the cache owner.
One of the lesser-known attractions at Singapore's Gardens by the Bay is The Canyon. With free entry, The Canyon features the world's largest collection of naturally-sculpted rocks, along a 400M trail inspired by the shape of a dragon.
These stones were brought here from Shandong, a region in China famous for granite production. As you walk along the path you can see more than 60 naturally-formed shapes, selected by the landscape architect Jun-ichi Inada. The largest of these shapes is 9m across and the tallest is 7m high.
At the end of the trail nearest the Bay, at the second waypoint, there is a tall Huabiao, an ornamental stone column popular in Chinese architecture. This intricately carved monument, also made of Shandong granite, stands 10m tall and gives an opportunity to compare the naturally formed stone against one carved by humans.
Granite:
Granite is an intrusive igneous rock with large mineral grains that can be easily seen with the naked eye, and is most commonly found in white, grey, pale pink and black. Granite is a conglomerate composed of different minerals, primarily quartz, feldspar, mica, amphibole, and trace amounts of others. Typically, granite contains 20-60% quartz, 10-65% feldspar, and 5-15% micas (biotite or muscovite).
Granite Colours:
The colouring of granite is due to the relative proportion of different coloured minerals - largely due to the composition of the original source of molten rock that cooled to form the granite. Common minerals are:
- Quartz – milky white
- Feldspar – off-white or pale pink
- Biotite – black or dark brown
- Muscovite – metallic gold or yellow
- Amphibole – black or dark green
Geological History of Shandong:
We don't know exactly where in Shandong (also called Shantung, Jiaodong or Chiaotung) this granite was sourced. However, the area has been extensively studied by geologists. It features a peninsula bordered by sea to the North, South and East. Currently it has a temperate monsoon climate which occasionally sees sub-freezing temperatures, but summer is characterised by frequent intense rainfall. The highest point is Laoshan Mountain, a granite peak of some 1133M. Since the Late Paleolithic era (approx 10k years ago) the region has been covered by forest. There is complex geography with caves, peaks, fjords and waterfalls. This intricate and beautiful geography attracts many tourists to the area.
In the Late Pleistocene era (aka the Ice Age, approx 2.5M to 10k years ago) the region was covered in an ice sheet. The ice sheet was drawn towards the Yellow Sea by gravity, but was disturbed in its flow by the moutains of Laoshan, Dazhu and Xiaozhu in the coastal areas. As the ice flowed towards the sea it eroded the bedrock and created many glacial potholes, scouring grooves in the the tops of granite ridges, and forming large boulders. Complex landforms including extensive caves were created by the movement of glaciers and meltwater. Also, there are caves likely formed by bubbles of gas that were trapped in the magma that initially formed the granite landscape. However the caves in the Laoshan Granite are much larger than formed in this manner elsewhere in the world.
So how did these ornate shapes form?
We're more used to seeing granite in thick uniform slabs as bench-tops or in building stones. But that stone has been selected because of its uniformity. The stones here in The Canyon were selected because of their beautiful natural shapes.
The process by which large sections of rock break down into smaller ones is called weathering. There are a few major types of weathering:
- Mechanical or Physical Weathering: Physical processes affect the rock, such as changes in temperature, exposure to wind, rain, waves and so on. Water can seep into cracks into rocks and if it freezes, the expanding ice can force the cracks wider. When the ice melts, more water fits into the larger crack, freezes in the next cold cycle and forces the rocks further apart. Wind can blow sand against rocks to wear them down, while waves crashing into rocks, or water or ice flowing over rocks can break them down over time.
- Chemical Weathering: Exposure to chemicals from water or the atmosphere can break down rocks. Rainwater is often slightly acidic due to dissolved carbon dioxide, which can cause a chemical reaction when in contact with rock. Pollutants in the atmosphere from human activity can have a similar effect.
- Biological Weathering: This is caused by the movement of plants and animals - including humans. An animal could burrow under a rock, weakening it. A plant may grow its roots in a crack and expand it as they grow. Humans or animals walking over a particular rock surface can wear it down. Humans digging rocks out, shaping them to a particular need or moving them from place to place can also break down the rock from its original state.
To claim this Earthcache:
Begin at the published coordinates. Make your way along the trail to the second waypoint - the Huabaio or ornamental column. Along the way you will pass many ornamental granite stone shapes, several sculptures and a variety of exotic plants.
- Choose a stone shape where you can see the effects of weathering. Please take a photo of yourself, your GPS, or some personal item with your selected stone shape in the background. Attach this photo to your log.
- Consider the natural processes that formed the shape of the stone you selected. What evidence can you see of different kinds of weathering?
- The ornately carved tower at the second waypoint, with its man-made surfaces, provides an opportunity to observe the visible grains which are a feature of granite. Describe the background colours and the visible grains. Which minerals do you think are present?
Please send your answers to questions #2 and #3 to me, via the messaging system or via email. You may post your Found log immediately without waiting for my response. If I don't receive correct answers within 30 days of your Found log being posted, I may delete your log. Please don't post answers to the questions above in your log.