earth science

Isalo III Formation

Isalo III 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 Isalo III Formation rather than just read about it. In short: The Isalo III Formation is a geological formation in Madagascar, off the eastern coast of Africa. It dates back to the Middle Jurassic.

Key takeaways

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

Reference excerpt

The Isalo III Formation is a geological formation in Madagascar, off the eastern coast of Africa. It dates back to the Middle Jurassic. The use of the term "Isalo III" is somewhat controversial as the two prior units Isalo I and II are Triassic cross-bedded sandstone units that form a continuous depositional sequence, while the "Isalo III" sandstones are not part of the same depositional sequence, and were deposited considerably later. and are perhaps better treated as part of several separate formations. It is traditionally divided into two subunits the lower, Bajocian aged Isalo IIIa unit also known as the Beronono Formation and the upper, Bathonian aged Isalo IIIb unit also known as the Sakaraha Formation or Sakahara Formation. The Sakaraha Formation consists of sandstones, marls and carbonates and represents a coastal plain environment, and is laterally equivalent to the predominantly carbonate Bemaraha Formation, which represents a coastal barrier lagoon complex. The formation is found in the northwest and in the southeast of the country and has provided a variety of fossils.

Fossil content Pterosaur teeth referred to Rhamphorhynchoidea are known from the formation.

Dinosaurs

Sauropods

Theropoda

Crocodyliformes

See also List of dinosaur-bearing rock formations List of fossiliferous stratigraphic units in Madagascar Geology of Madagascar

References

Bibliography Royo Torres, Rafael; Cobos, Alberto; Mocho, Pedro; Alcalá, Luis (2021). "Origin and evolution of turiasaur dinosaurs set by means of a new 'rosetta' specimen from Spain". Zoological Journal of the Linnean Society. 191: 201–227. doi:10.1093/zoolinnean/zlaa091. Bindellini, Gabriele; Sasso, Cristiano Dal (2019). "Sauropod teeth from the Middle Jurassic of Madagascar, and the oldest record of Titanosauriformes". Papers in Palaeontology. 7: 137–161. doi:10.1002/spp2.1282. S2CID 203376597. Dal Sasso, Cristiano; Pasini, Giovanni; Fleury, Guillaume; Maganuco, Simone (2017). "Razanandrongobe sakalavae, a gigantic mesoeucrocodylian from the Middle Jurassic of Madagascar, is the oldest known notosuchian". PeerJ. 5 e3481. doi:10.7717/peerj.3481. PMC 5499610. PMID 28690926. Geiger, Markus; Clark, David Norman; Mette, Wolfgang (2004). "Reappraisal of the timing of the breakup of Gondwana based on sedimentological and seismic evidence from the Morondava Basin, Madagascar". Journal of African Earth Sciences. 38 (4): 363–381. Bibcode:2004JAfES..38..363G. doi:10.1016/j.jafrearsci.2004.02.003. Weishampel, David B.; Dodson, Peter; Osmólska, Halszka, eds. (2004). The Dinosauria (2nd ed.). Berkeley: University of California Press. pp. 1–880. ISBN 9780520941434. Thevenin, A (1907). "Paléontologie de Madagascar. IV Dinosauriens" (PDF). Annales de Paléontologie. 2: 121–136.

Further reading É. Buffetaut. 2005. A new sauropod dinosaur with prosauropod-like teeth from the Middle Jurassic of Madagascar. Bulletin de la Société Géologique de France 176(5):467-473 S. Maganuco, C. Dal Sasso, and G. Pasini. 2006. A new large predatory archosaur from the Middle Jurassic (Bathonian) of Madagascar. Atti della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano 147(1):19-51 J. J. Flynn, J. M. Parrish, B. Rakotosamimanana, W. F. Simpson, and A. R. Wyss. 1999. A Middle Jurassic mammal from Madagascar. Nature 401:57-60 A. Ogier. 1975. Etude de Nouveaux Ossements de Bothriospondylus (Sauropode) d'un Gisement du Bathonien de Madagascar [Study of New Bones of Bothriospondylus (Sauropod) from a Locality from the Bathonian of Madagascar]. Sciences Naturelles, Université de Paris VI 1-111 M. Collignon. 1954. Decouverte de dinosauriens a Tsinjorano, district d'Ambato-Boeni [Discovery of dinosaurs at Tsinjorano, Ambato-Boeni district]. Bulletin de l'Académie Malgache 31:59-61

Illustrations

Worked examples

Example 1 — a first encounter with Isalo III Formation

Start with the simplest possible case. Write down what Isalo III 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 Isalo III 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 Isalo III 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 Isalo III Formation

In research: Isalo III 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 Isalo III 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: Isalo III Formation is common in secondary-school and first-year university syllabi. It links to neighbouring topics Bajocian Stage, Bathonian Stage, Geologic formations of Madagascar, so understanding it makes those chapters shorter.
In everyday life: Look for Isalo III 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 Isalo III Formation in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Isalo III 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 Isalo III Formation out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Isalo III Formation in simple terms?

The Isalo III Formation is a geological formation in Madagascar, off the eastern coast of Africa. It dates back to the Middle Jurassic.

Why does Isalo III 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 Isalo III 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 Isalo III Formation.