earth science

Kaili Formation

Kaili Formation 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 Kaili Formation rather than just read about it. In short: The Kaili Formation (simplified Chinese: 凯里组; traditional Chinese: 凱里組; pinyin: Kǎilǐ zǔ) is a stratigraphic formation which was deposited during the Lower and Middle Cambrian (~513 to 506 million years ago). The formation is approximately 200 metres (660 ft) thick and was named after the city Kaili in the Guizhou province of southwest China.

Key takeaways

Kaili Formation 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 Kaili Formation to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Kaili Formation from memory before moving on to harder problems.

Reference excerpt

The Kaili Formation (simplified Chinese: 凯里组; traditional Chinese: 凱里組; pinyin: Kǎilǐ zǔ) is a stratigraphic formation which was deposited during the Lower and Middle Cambrian (~513 to 506 million years ago). The formation is approximately 200 metres (660 ft) thick and was named after the city Kaili in the Guizhou province of southwest China. The depositional environment of the Kaili Formation is not entirely known, and there are two hypotheses for its formation. It may have been a nearshore marine environment with 'normal' levels of oxygenation; or it may have been a deeper water environment further from the shore, on the open continental shelf; in this setting oxygen would not be available below the surface layers of the deposited sediment. The trace fossil assemblages in the formation suggest that it was below the wave base and was reasonably well-oxygenated.

Fossils The faunal assemblage is highly diverse, comprising some 110 genera among 11 phyla; of these, some 40 genera are also found in the Burgess Shale, and some 30 are also found in the Maotianshan Shale. Trilobites and eocrinoids with hard parts that are easily preserved are the most common fossils, but many animals with only soft tissues are also preserved. For example, the arthropod Skania similar to the Ediacaran Parvancorina of the Neoproterozoic age Ediacara Hills of South Australia has been found at the Kaili site. The middle part of the Kaili Formation, the Oryctocephalus indicus Zone, contains a Burgess Shale-type Lagerstätte with many well-preserved fossils known collectively as the Kaili Biota. In terms of age, this biota is located between the two most important and famous Cambrian Lagerstätten: the middle Lower Cambrian Maotianshan Shale (containing the Chengjiang Biota), also from China: and the Middle Cambrian Burgess Shale, known from Canada. Some other notable fossils discovered at Kaili are putative invertebrate eggs and embryos, trace fossils of the genus Gordia (not to be confused with the Gordian worms), as well as Naraoia, chancellorids, Microdictyon, Wiwaxia, and Marrella. Furthermore, the possible moss Parafunaria is also known, marking the earliest likely fossil of land plants. However this fossil has been disputed, as its Cambrian age means more conclusive proof is needed to determine whether it truly is a moss. The Kaili Formation is subdivided into three trilobite zones:

Bathynotus holopygous–Ovatoryctocara granulata Zone Oryctocephalus indicus Zone Olenoides jialaoensis Zone

Paleobiota

Animals

Other taxa

GSSP for the Cambrian Series 3 An outcrop of the Kaili Formation, the Wuliu-Zengjiayan section, was a candidate for the GSSP for the beginning of the 5th stage of the Cambrian. The FAD of two trilobites from the formation are proposed to be the official stage boundary, Oryctocephalus indicus and Ovatoryctocara granulata. Both can be correlated with formations of similar age in Siberia and China. In 2018, GSSP for the Miaolingian series (Cambrian Series 3, "Middle" Cambrian) as well as the Wuliuan stage was finally defined in this formation.

References

Illustrations

Worked examples

Example 1 — a first encounter with Kaili Formation

Start with the simplest possible case. Write down what Kaili Formation 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 Kaili Formation 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 Kaili Formation 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 Kaili Formation

In research: Kaili Formation 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 Kaili Formation 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: Kaili Formation is common in secondary-school and first-year university syllabi. It links to neighbouring topics Cambrian China, Cambrian System of Asia, Cambrian northern paleotemperate deposits, so understanding it makes those chapters shorter.
In everyday life: Look for Kaili Formation 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.

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How to study Kaili Formation in 20 minutes

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

Frequently asked questions

What is Kaili Formation in simple terms?

Why does Kaili Formation 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 Kaili Formation?

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 Kaili Formation.