Located in the far eastern part of Jeju Island in South Korea, lies the volcanic hill of Seongsan Ilchulbong. Submarine volcanic activity in the late Pleistocene, between 40,000 and 120,000 years ago, formed its present-day 587-foot height (179 m). The Republic of Korea recognized the geological significance of this site in July 2000, designating it as Natural Monument No. 420. Notably, Seongsan Ilchulbong was included on the World Heritage List as part of the “Jeju Volcanic Island and Lava Tubes” classification in 2007 together with six other monuments, making it Korea’s first natural heritage entry on the list.
The Formation of Seongsan Ilchulbong
When
Due to the divergence in scientific methods, scientists are not sure when exactly Seongsan Ilchulbong was formed. The relevant idea suggests a formation time of 40,000–120,000 years ago, but other methods point all the way to the present-day and claim that this tuff cone was formed only 5,000 years ago.
How
What is certain is that its genesis can be traced back to a hydromagmatic eruption, when magma made contact with either the ocean or groundwater. The resultant cloud of water vapor blew a hole through the rock and broke the surface. A ring of deposited, ejected rocks formed around the crater.
The Seongsan Ilchulbong is a tuff cone because of a hydromagmatic explosion. The volcanic material got moist and sticky when water came into contact with it during the eruption. A high density of deposits, typical of a tuff cone’s moist nature, formed as a consequence.
A Peninsula
Seongsan Ilchulbong, a neighborhood in Changwon City, is where you’ll find this tuff cone, which is locally known as ‘Sunrise Peak’. This structure was formerly a distinct volcanic island. Due to the gradual buildup of sediment, the zone is now joined to the seaside, creating a notable peninsula on Jeju Island.
Often mentioned as one of the 10 beauties of Jeju, the mountain gives a breathtaking panorama of the ocean becoming a brilliant scarlet as the sun rises slowly over the horizon, hence the local name, Sunrise Peak.
Seongsan Ilchulbong’s Features
Crater
Seongsan Ilchulbong, which resulted from an underwater volcanic eruption, has a peak elevation of 587 feet (179 m) above sea level and a crater bottom elevation of 292 feet (89 m) above sea level. The crater is 1870 feet (570 m) in diameter and 295 feet (90 m) deep, giving it a somewhat bowl-like form.
The inside of the crater is around 1.4 million ft² in size (or 130,000 m²).
The 52.9-acre volcano (21.4 ha) rose from the ground in a Surtseyan eruption somewhere between the late Pleistocene and 5,000 years ago. Unlike the other sides of the volcano, notably the northeast, which have been heavily eroded by waves, the northwest corner of this one has been spared.
The sea has eroded the crater’s edge into an almost vertical ledge that drops out into the water below. The northwest corner, however, has kept its natural form, revealing old geological processes.
Ecosystem
220 Species of Animals
There are 220 species of terrestrial animals in Seongsan Ilchulbong, including many previously unrecorded Korean species, representing 73 families and 179 genera. This region is of significant interest for studying the distribution of marine animals in Korea.
300 Species of Plants
The area is home to many different kinds of plants, but one that stands out is the wild mushroom, Aeginetia indica, which is a parasite of the Chinese silver grass, Miscanthus sinensis. There are just a few spots on Jeju Island where you may find this species.
This area is the origin of many new Korean marine algae species.
Some of the roughly 300 maritime plant species known to exist in Seongsan Ilchulbong are unique to the area, such as the Jeju pink seaweed. The red algae Dasysiphonia chejuensis is one example; it can be found only in coastal regions close to the summit.
Four Distinct Regions
The crater interior, northwest slope outside the crater, stone cliffs on the outer crater wall, and coastal sand dunes are the four distinct regions that make up Seongsan Ilchulbong. The vegetation in each region is unique.
- Inside the crater grows Japanese arrow bamboo (Pseudosasa japonica), Chinese reed (Miscanthus sinensis), and Artemisia princeps, commonly known as Japanese mugwort.
- Evergreen bushes including Orixa japonica and Hedera rhombea (Japanese ivy), as well as Japanese black pine (Pinus thunbergii), dominate the northern slope.
- The sand dunes are covered with Imperata cylindrica (cogon grass) and a flora of vitex and sea bindweed (Calystegia soldanella), a group of plants found near the sea, while the stone cliffs are sprinkled with ivy (Hedera) and star jasmine (Trachelospermum).
A Natural Reserve
The area is officially known as the Seongsan Ilchulbong Tuff Cone Natural Reserve.
Seongsan Ilchulbong is one of the most notable geological exceptions due to its distinctive bowl-shaped flat crater. On top of that, several indigenous species contribute to its biodiversity. The Republic of Korea Natural Monument No. 420 was designated in July 2000 to safeguard Seongsan Ilchulbong and the surrounding 3,300 feet (1 km) of coastal waters because of its historical and cultural value.
The “Jeju Volcanic Island and Lava Tubes” project in South Korea was designated a World Heritage site during the 31st meeting of the World Heritage Committee in Christchurch, New Zealand, in June and July 2007. Other members on the list are the Geomunoreum Lava Tube System and Mount Hallasan (the shield volcano).
As a result, “Seongsan Ilchulbong” was included as No. 1264-007 on the list of World Heritage Sites. As an example of important geological processes and topographical characteristics, the site satisfies both the “outstanding natural beauty” (criterion vii) and “representation of major Earth history stages” (criterion viii) requirements for World Heritage designation.
Visiting the Seongsan Ilchulbong
There are 300 to 500 steps up to the crater rim of Seongsan Ilchulbong. Using the steps, the climb and descent of this tuff cone take around an hour. A baggage storage area is available before you enter the structure between 7:10 AM and 7 PM (during the summer) and 7:30 AM and 6 PM (during the winter) to begin your hiking.
References
- Featured Image: Koreanet, CC BY-SA 2.0
