earth science

Oxfordian age

Oxfordian age 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 Oxfordian age rather than just read about it. In short: The Oxfordian is, in the ICS' geologic timescale, the earliest age of the Late Jurassic Epoch, or the lowest stage of the Upper Jurassic Series. It spans the time between 161.5 ± 1.0 Ma and 154.8 ± 0.8 Ma (million years ago).

Key takeaways

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

Reference excerpt

The Oxfordian is, in the ICS' geologic timescale, the earliest age of the Late Jurassic Epoch, or the lowest stage of the Upper Jurassic Series. It spans the time between 161.5 ± 1.0 Ma and 154.8 ± 0.8 Ma (million years ago). The Oxfordian is preceded by the Callovian and is followed by the Kimmeridgian.

Stratigraphic definitions The Oxfordian Stage was called "Clunch Clay and Shale" by William Smith (1815–1816); in 1818 W. Buckland described them under the unwieldy title "Oxford, Forest or Fen Clay". The term Oxfordian was introduced by Alcide d'Orbigny in 1844. The name is derived from the English city of Oxford, where the beds are well developed, but they crop out almost continuously from Dorset to the coast of Yorkshire, generally forming low, broad valleys. They are well exposed at Weymouth, Oxford, Bedford, Peterborough, and in the cliffs at Scarborough, Red Cliff and Gristhorpe Bay. Rocks of this age are found also in Uig and Skye. The base of the Oxfordian Stage is defined as the point in the stratigraphic record where the ammonite species Brightia thuouxensis first appears. A global reference profile for the base (a GSSP) had in 2009 not yet been assigned. The top of the Oxfordian Stage (the base of the Kimmeridgian) is at the first appearance of ammonite species Pictonia baylei. In the Tethys domain, the Oxfordian contains six ammonite biozones:

zone of Epipeltoceras bimammatum zone of Perishinctes bifurcatus zone of Gregoryceras transversarium zone of Perisphinctes plicatilis zone of Cardioceras cordatum zone of Quenstedtoceras mariae

References

Notes

Literature Brongniart, A.; 1829: Tableau théorique de la succession et de la disposition la plus générale on Europa, des terrains et roches, qui composent l'écorce de la terre, Paris.(in French) Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; 2004: A Geologic Time Scale 2004, Cambridge University Press.

External links GeoWhen Database - Oxfordian Jurassic-Cretaceous timescale, at the website of the subcommission for stratigraphic information of the ICS Stratigraphic chart of the Upper Jurassic, at the website of Norges Network of offshore records of geology and stratigraphy

Illustrations

Worked examples

Example 1 — a first encounter with Oxfordian age

Start with the simplest possible case. Write down what Oxfordian age 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 Oxfordian age 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 Oxfordian age 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 Oxfordian age

In research: Oxfordian age 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 Oxfordian age 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: Oxfordian age is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1827 introductions, Culture in Oxford, Geological ages, so understanding it makes those chapters shorter.
In everyday life: Look for Oxfordian age 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 “Oxfordian age” →

Affiliate

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

How to study Oxfordian age in 20 minutes

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

Frequently asked questions

What is Oxfordian age in simple terms?

Why does Oxfordian age 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 Oxfordian age?

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 Oxfordian age.