ArticleslgStudy

earth science

Krakatoa archipelago

Krakatoa archipelago is a earth science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Krakatoa archipelago rather than just read about it. In short: The Krakatoa Archipelago is a small uninhabited archipelago of volcanic islands formed by the Krakatoa stratovolcano located in the Sunda Strait, nestled between the much larger islands of Java and Sumatra. As of 2018, the archipelago consists of four main islands: Verlaten (a.k.a.

Krakatoa archipelago — main illustration
Krakatoa archipelago — illustration

Key takeaways

  • Krakatoa archipelago belongs to earth science; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Krakatoa archipelago to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Krakatoa archipelago from memory before moving on to harder problems.

Reference excerpt

The Krakatoa Archipelago is a small uninhabited archipelago of volcanic islands formed by the Krakatoa stratovolcano located in the Sunda Strait, nestled between the much larger islands of Java and Sumatra. As of 2018, the archipelago consists of four main islands: Verlaten (a.k.a. Sertung) to the northwest, Lang (a.k.a. Rakata Kecil, or Panjang) to the northeast, Rakata (what remains the main island) to the south, and the currently volcanically active Anak Krakatoa in the north-centre. Together, the islands are a part of the Indonesian island arc system, created by the northeastward subduction of the Indo-Australian Plate. As part of a dynamic volcanic system, the islands have been continuously reshaped throughout recorded history, most notably in the 1883 eruption of Krakatoa. Administratively, the Krakatoa Archipelago lies entirely within Lampung, Indonesia and forms a part of Ujung Kulon National Park.

Geology

Krakatoa is an active stratovolcano located in Indonesia, and lying on the far western rim of the Pacific "Ring of Fire." Krakatoa is a notably powerful volcano, with the 1883 eruption being one of the deadliest and most destructive volcanic events in all of recorded history.

Geography

Current Islands Verlaten Island (a.k.a. Sertung) – Verlaten is a rather low island with a hill in the middle. Other than some minor collapse in the southeast (closest to the main island of Krakatoa), Verlaten suffered little damage in the 1883 eruption. Instead, it grew almost 3 times in area due to pumice fall, although most of the gain was quickly eroded away. After the 1883 eruption, Verlaten developed a low spit of land to the north-east with a brackish lake near the end. This lake became a waterfowl haven but has since been breached by wave erosion. Lang Island (a.k.a. Lesser Krakatoa, or Panjang) – Lang, by contrast, is quite hilly. It suffered only slightly in the 1883 eruption; it actually grew in area from massive pumice fall, although most of the additional area washed away within several years. Rakata (a.k.a. Greater Krakatoa) – Standing 813 metres (2,667 feet) tall, it was the largest and southern-most of three volcanoes that formed the now destroyed island of "Krakatoa" (the others being Danan and Perboewatan), and the only one not obliterated in the eruption of 1883. However, Rakata did lose its northern half in that eruption - leaving just its southern half. The exposed cliff is quite striking visually, partially of a large exposed dike terminating in a large lenticular extrusion at the middle of the almost vertical cliff. The feature has been called "the Eye of Krakatoa." Anak Krakatoa – Following the 1883 eruption, Krakatoa's lava dome was entirely beneath the surface of the ocean. However, in December 1927, an eruption led to a new island that rose above the waterline. The eruptions were initially of pumice and ash, and that island and the two islands that followed were quickly eroded away by the sea. Eventually a fourth island named Anak Krakatau (meaning "child of Krakatoa" in Indonesian) broke water in August 1930, and produced lava flows more quickly than the waves could erode them.

Former islands Poolsche Hoed (Dutch: "Polish Hat") – a former small rocky islet between Krakatoa Island and Lang Island, which was destroyed in the 1883 eruption. The name was apparently derived from its appearance from the sea: a sharply angled point, similar to the old-styled caps worn by Poles. Calmeyer (sometimes spelled Calmejer) – a former island created from volcanic products from the 1883 eruption of Krakatoa, in the Sebesi Channel between Krakatoa Island and Sebesi, which was a fairly shallow area (about 20 meters before the eruption). Calmeyer was somewhat higher than Steers, at about 6.5 meters at the highest spot. The two rather quickly were eroded away by wave action; Calmeyer had broken up into about half a dozen smaller islets by the time of Rogier Verbeek's visit in October 1883, and was gone within two years. Sandbanks bearing the names still remain. Steers (island) – a former island created from volcanic products from the 1883 eruption of Krakatoa, in the Sebesi Channel between Krakatoa Island and Sebesi. Steers was the slightly larger of the two, but never was more than three meters above the waterline. They were rather quickly eroded away by wave action, and were gone within two years. Sandbanks bearing the names still remain.

Gallery

See also Sebesi

References

Simkin, Tom and Richard S. Fiske (1983). Krakatau, 1883—the volcanic eruption and its effects. Smithsonian Institution Press. ISBN 0-87474-841-0. Rupert Furneaux (1964). Krakatoa. Prentice-Hall. ISBN 1111751633. {{cite book}}: ISBN / Date incompatibility (help) Quammen, David (1996). The Song of the Dodo: Island Biogeography in an Age of Extinctions. New York: Simon & Schuster. pp. 141–151. ISBN 0-684-82712-3.

Illustrations

Krakatoa archipelago illustration
Krakatoa archipelago: The change in topology after the 1883 eruption
The change in topology after the 1883 eruption
Krakatoa archipelago illustration
Krakatoa archipelago illustration
Krakatoa archipelago illustration

Worked examples

Example 1 — a first encounter with Krakatoa archipelago

Start with the simplest possible case. Write down what Krakatoa archipelago claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In earth science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Krakatoa archipelago before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Krakatoa archipelago ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Krakatoa archipelago

In research
Krakatoa archipelago appears in earth science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Krakatoa archipelago in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Krakatoa archipelago is common in secondary-school and first-year university syllabi. It links to neighbouring topics Active volcanoes of Indonesia, Archipelagoes of Indonesia, Calderas of Indonesia, so understanding it makes those chapters shorter.
In everyday life
Look for Krakatoa archipelago outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Krakatoa archipelago” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Krakatoa archipelago in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Krakatoa archipelago means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Krakatoa archipelago out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Krakatoa archipelago in simple terms?

The Krakatoa Archipelago is a small uninhabited archipelago of volcanic islands formed by the Krakatoa stratovolcano located in the Sunda Strait, nestled between the much larger islands of Java and Sumatra. As of 2018, the archipelago consists of four main islands: Verlaten (a.k.a.

Why does Krakatoa archipelago matter?

Because it connects several earth science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Krakatoa archipelago?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Krakatoa archipelago.

Tags

  • Active volcanoes of Indonesia
  • Archipelagoes of Indonesia
  • Calderas of Indonesia
  • Islands of the Sunda Strait
  • Krakatoa
  • Subduction volcanoes
  • Submarine calderas

Keep exploring