Rocks, waves, and wonder: BEd(GEOG) students explore Sai Kung’s natural treasures

On 11 April, 15 students from the Bachelor of Education (Honours) (Geography) (BEd(GEOG)) programme and two students from a non-BEd(GEOG) programme embarked on a long-awaited fieldtrip to Sai Kung. The excursion proved intellectually stimulating as students observed and applied textbook knowledge to explain geological formations. Excitement abounded as they navigated dark, narrow sea arches, and enjoyment was found as the ferry sailed through the breathtaking waters of what is often called the “Back Garden of Hong Kong”. It was truly a once-in-a-lifetime experience that participants will remember for many years to come.

The fieldtrip forms a core component of the Geomorphology and Hydrology course (Code: GGP4010) jointly offered by the Department of Science and Environmental Studies (SES) and the Department of Social Sciences and Policy Studies (SSPS) within the BEd(GEOG) programme. On the morning of 11 April, students, together with course instructor Dr Irene Cheng Nga-yee from SES, and other supporting staff from both departments boarded a ferry at Sai Kung Public Pier. The group headed south to Port Shelter, where they observed, identified and sketched coastal landforms, noting both natural and erosion features, and human modifications to the landscape. Dr Cheng encouraged students to consider how natural forces such as wind, water currents, tectonic movements, and volcanic activity have shaped the region’s evolution.

The ferry next took the group to Tiu Chung Chau (aka Jin Island), where students used geological tools to measure the height of a sea arch on the Island. The ferry anchored at a distance from the sea arch approximately equal to the estimated height of the cave. Students then employed a clinometer to measure the titling angle from the ferry to the top of the arch. A group of students reached the arch by a small boat and measured the actual distance between the ferry and the cave using a rope.

“With the titling angle and the actual distance measured, students can apply tangent formula to estimate the height of the arch,” explained Dr Cheng. Inside the arch, students observed and estimated the difference between the low and high water marks. “The course taught them how sea arches are formed through erosion, primarily by waves, along coastlines. The fieldtrip offered them a valuable opportunity to apply their geological knowledge to explain the formation of an arch. It was an excellent learning experience for them,” she said.

Another exciting moment of the fieldtrip came when the ferry reached Sha Tong Hau (aka Bluff Island). Students transferred in small groups to a smaller boat to pass through Sha Tong Hau Cave (aka Bluff Island Cave). Here, participants sketched the cave and explained how natural forces contributed to its formation. The final stop was Nam Fung Bay (aka Ma Tau Wan) where students conducted beach studies.

“Cave is a misnomer. Sha Tong Hau Cave and other famous caves in Sai Kung are actually sea arches. They are tunnels in the sea that people can pass through from one end to the other,” explained Gordon Shum Tsz-chun, a fourth-year student from the BEd(GEOG) programme. “As Sha Tong Hau Cave is narrow and dark, passing through it requires a sense of adventure. It was quite a special experience,” he recalled, still excited by the memory of traversing the sea tunnel.

Like Gordon, Esther Lau Po-yue also found the fieldtrip both inspiring and exhilarating. “When the ferry sailed through the waters of Sai Kung, we were able to closely observe and sketch the effects of coastal erosion. At Nam Fung Bay, we studied the characteristics of beach sediments and measured the area of the beach by dividing it into small regions using straight transect lines from the water’s edge to the beach’s end. I noticed that the gradient of the beach increased as we approached its boundary,” said the fourth-year geography major.

Esther has a keen interest in physical geography, as the subject provides insight into Hong Kong’s geology. “I am particularly interested in geological courses such as Geomorphology and Hydrology. From these courses, I have learnt about the various types of rocks in Hong Kong, and how they were formed. For instance, I discovered that a volcanic eruption occurred 140 million years ago in Sai Kung, creating the area’s unique geological features. The fieldtrip allowed us to observe these features up close,” Esther said.

“Sai Kung is renowned for its world-class geological formations. The fieldtrip gave students the opportunity to apply theoretical knowledge to real-world geological studies. By observing geological features directly in the field, students gained a deeper understanding of the effects of geological processes. They also practised drawing geological sketches, reading maps, and using various geological tools and techniques to measure natural features. Seeing physical geography in real life is a transformative and highly rewarding learning experience,” Dr Irene Cheng from SES said.

Participating in a fieldtrip in an area celebrated for its picturesque coastal views, rolling green hills, rugged cliffs, and crystal-clear waters created fond memories that will last a lifetime for many students. “We are grateful to both SES and SSPS for organising this study tour. As the ferry approached the East Dam of the High Island Reservoir, we were captivated by the beauty of the natural landscape. We all thoroughly enjoyed the excursion. As the ferry travelled from one island to another, we worked on course assignments, chatted, took selfies, and marvelled at the wonders of nature. It was a day packed with excitement, joy, and learning,” Gordon said.

Click here to learn more about the Bachelor of Education (Honours) (Geography) programme, and here for information on the Bachelor of Social Sciences (Honours) in Sociology and Community Studies and Bachelor of Education (Honours) (Geography) double-degree programme.