Booklet of Sangkulirang Mangkalihat Aspiring National Geopark

THE

SANGKULIRANG-

MANGKALIHAT

ASPIRING NATIONAL GEOPARK

EAST KALIMANTAN, INDONESIA

Support Y20, Indonesia, 2022

The Sangkulirang-Mangkalihat Aspiring Geopark Profile




Administratively, the Sangkulirang-Mangkalihat Aspiring Geopark area is located in East
Kutai Regency and Berau Regency, East Kalimantan Province.

The geological tectonic history of this area cannot be separated from the formation of
the Mangkalihat Peninsula and the Kutai Basin. The Mangkalihat Peninsula is located in
the northern part of Kalimantan, physiographically this height separates between the
Kutai basin (in the south) and Tarakan (in the north) and is part of Sundaland.
Mangkalihat was one of the north
ern microcontinents of Gondwana at the beginning of
its development, crossing the equatorial zone in the Jurassic period (> 160 million years
ago) as a result of the expansion of the CenoTethys Ocean (Metcalfe, 1994; Satyana,
2003). In general, the rocks that are found on the Mangkalihat Peninsula consist of
clastic sedimentary rocks and carbonate sedimentary rocks. This is characterized by
the appearance of karst hills, which are very unique and become the main assets of the
geological sites in the Sangkulirang-Mangkalihat Aspiring Geopark area. In addition,
there are also traces of human life in the past in this karst area, which are shown in
ancient paintings, in the form of handprints and animal drawings on the cave walls.

Besides karst landscapes, this area also has other interesting geological diversities,
such as: 1) the occurrence of hot springs in East Kalimantan, which is geologically non-
volcanic; 2) deltaic deposits, where most of the depositional environment in this region
is marine environment; 3) ultramafic rocks, which are part of the Jurassic Ophiolite
Rock Unit (> 160 million years ago); and 4) deep-sea sediments, which are the result of
the accretion of the Mangkalihat microcontinent to the Sunda continent (Sundaland) in
the period 150 to 60 million years ago (late Jurassic - early Tertiary).

There are currently 29 geological objects (geosites) proposed to the Ministry of Energy
and Natural Resources of the Republic of Indonesia for geological heritage designation.
These geosites are divided into 8 clusters (figure 1), namely the Suaran cluster, the
Biatan-Batu Putih cluster, the Bidukbiduk-Tanjung Mangkalihat cluster, the Merabu
cluster, the Gunung Gergaji cluster, the Baay-Pengadan cluster, the Batu Lepoq cluster,
and the Batu Onyen cluster. Determining geological heritage is very important as it
serves as one of the prerequisites for designating a geopark. Meanwhile, the inventory
of geological objects in the Sangkulirang-Mangkalihat aspiring geopark area is still

being carried out, so the geological heritage will increase in number1in the future.

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The Sangkulirang-Mangkalihat Aspiring Geopark GEOSITES MAP






Figure 1. Distribution of geosites to be designated as geological heritage

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PROPTHOESEPDRGOPEOOSHEEDRIGTAEOGHEESRIITTEASGE SITES






Picture 1. Ultramafic outcrop (ophiolite).
Ultramafic window outcrop that is part of the Jurassic Ophiolite Rock Unit.
Ultramafic rocks that are uplifted by regional tectonic processes and come
into contact with seawater so that the mineral constituents become
serpentine minerals



























Picture 2. Deep sea sedimentary outcrops (chert)
Deep-oceanic sedimentary outcrops (chert) from the Late Jurassic to the

Early Cretaceous of the Telen Formation. The chert occurs1 at a depth

below the limit of the carbonate compensation depth (CCD) layer with a
depth of more than 4000 m. These rocks were then brought to the surface
by regional tectonic processes.

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PROPOSED GEOHERITAGE SITES




Picture 3. Gabbro outcrop (ophiolite)
This outcrop is part of the Cretaceous ophiolite. The lithology has
been fractured intensively. Gabbro is the most abundant rock in
the oceanic crust

Picture 4. Tiga Bidadari
Waterfall

This site is located in the Golok
Formation from the late
Miocene-Pliocene age. The
basic lithology of this waterfall
is marl. The waterfall has two
levels and the height of the first
level is about 30 m.

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PROPOSED GEOHERITAGE SITES




Picture 5. Karst landscape which is the most outstanding
landscape of Sangkulirang Mangkalihat Geopark

Picture 6. Karst Landscape
The limestones in the Mangkalihat Heights were formed when this
area was inundated due to the expansion of the Makassar Strait in
the Middle Eocene age (50 million years ago). Carbonate rocks
were deposited in shallow marine environments, either as clastic
limestone deposits, isolated reefs, to deep sea redeposition
environments. The oldest Eocene limestones are located in the
westernmost part and gradually get younger towards the east and
north. The youngest limestone in this region is the Miocene-
Pliocene on the Domaring Formation

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PROPOSED GEOHERITAGE SITES




Picture 7. Karst Landscape From Air
The limestones in the Mangkalihat Heights were formed when this area
was inundated due to the expansion of the Makassar Strait in the
Middle Eocene age (50 million years ago). Carbonate rocks were
deposited in shallow marine environments, either as clastic limestone
deposits, isolated reefs, to deep sea redeposition environments. The
oldest Eocene limestones are located in the westernmost part and
gradually get younger towards the east and north. The youngest
limestone in this region is the Miocene-Pliocene on the Domaring
Formation

Picture 8. Bottle Tower
The Bottle karst is one of the most unique forms of Sangkulirang
Mangkalihat Karst. It is the formation of a karst tower with a circular
hole at the top with a depth that reaches the bottom of the tower.

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PROPOSED GEOHERITAGE SITES




Picture 9. Ancient Historical Painting
There are historical artwork in the shape of handprints and animals inside

the cave of the Sangkulirang-Mangkalihat karst area. These paintings are the

uniqueness of the Karst. The paintings are known to be 40,000 years old.

Picture 10. The deltaic sediment
of Latih Formation

The deltaic deposits in the

Sangkulirang-Mangkalihat area

belong to the Middle Miocene

age on the Latih Formation with

alternating lithology of

sandstone and claystone with a

cross bedding structure, parallel

lamination, thin carbon inserts,

and clay concretions.

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PROPOSED GEOHERITAGE SITES




Picture 11. The hot spring
The occurrence of non-volcanic hot springs that come out at limestones in the
Sangkulirang – Mangkalihat Karst Area are controlled by a northwest-southeast
trending structure which is estimated as a fault activity.

Picture 12. The Dome Karst
A complex form of dome and cockpit karst are found in
downstream/coastal karst. Karst hills tend to be rounded due to the
intensive melting process in all directions.

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PROPOSED GEOHERITAGE SITES




Picture 13. Tebo Lake or Polje
Polje or wide pool with relatively flat bottoms, form a very impressive

landscape in the Kulat karst block. Locals refer to Polje as Tebo.

Picture 14. Labuan Cermin
Lagoon on the coast of Biduk-Biduk. The water is very clear so that we
can see the bottom of the lake. There are two types of water in this
lagoon: salt water from the sea and fresh water from karst springs.
Uniquely, the two types of water do not mix with each other but
separate naturally. The presence of fresh water is on the surface of the
lake with a depth of about 0‐4 meters then the rest is salt water

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