earth science

Shackleton Limestone

Shackleton Limestone 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 Shackleton Limestone rather than just read about it. In short: The Shackleton Limestone is a Cambrian limestone formation of the Byrd Group of the Ross Dependency in Antarctica. The age of the formation is established to be Cambrian Stage 3, dated at ranging from 520 to 516 Ma.

Key takeaways

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

Reference excerpt

The Shackleton Limestone is a Cambrian limestone formation of the Byrd Group of the Ross Dependency in Antarctica. The age of the formation is established to be Cambrian Stage 3, dated at ranging from 520 to 516 Ma. This period correlates with the End-Botomian mass extinction. Fossils of trilobites and Marocella mira and Dailyatia have been found in the formation, named after Ernest Shackleton, who led a failed expedition into Antarctica. At time of deposition, the Antarctic Plate has been established to be just south of the equator as part of the supercontinent Pannotia, contrasting with its present position at 82 degrees southern latitude.

Geology The formation, named by Laird in 1963, crops out in the Churchill Mountains, part of the Transantarctic Mountains of southwestern Antarctica. The most complete exposures are in the Holyoake Range. Paleontological data and carbon isotope stratigraphy indicate that the Shackleton Limestone ranges from lower Atdabanian through upper Botomian. The formation is a thick carbonate deposit with a lower unit of unfossiliferous interbedded quartzite and limestone, overlies the Late Proterozoic argillaceous turbidite Goldie Formation and underlies the Starshot Formation. Other lithologies noted in the Shackleton Limestone are marble with breccia, conglomerate, sandstone and shale. The abrupt transition from the Shackleton Limestone to a large-scale, upward coarsening siliciclastic succession records deepening of the outer platform and then deposition of an eastward-prograding molassic wedge. The various formations of the upper Byrd Group show general stratigraphic and age equivalence, such that coarse-grained alluvial fan deposits of the Douglas Conglomerate are proximal equivalents of the marginal-marine to shelf deposits of the Starshot Formation. The sandstone-rich lower member of the Shackleton Limestone is exposed at Cotton Plateau beneath Panorama Point, where it consists of up to 133 metres (436 ft) of interbedded white- to cream-weathering, vitreous, quartz sandstone and brown-weathering, white, fine-grained dolomitic grainstone. These beds are in fault contact with the adjacent Goldie Formation. The formation postdates the Beardmore Orogeny of the Neoproterozoic, and was deformed by the Ross Orogeny.

Fossil content The formation has provided fossils of trilobites such as Holyoakia granulosa, Pagetides (Discomesites) spinosus, Lemdadella antarcticae, Kingaspis (?) convexus, Yunnanocephalus longioccipitalis, and Onchocephalina (?) spinosa. Other fossils found are Marocella mira, and Dailyatia odyssei and D. braddocki.

See also List of fossiliferous stratigraphic units in Antarctica Geology of Antarctica Fremouw Formation

References

Bibliography Elliot, David H (1975), "Tectonics of Antarctica: A Review" (PDF), American Journal of Science, 275-A: 45–106, retrieved 2018-05-22 Laird, M.G.; Mansergh, G.D.; Chappell, J.M.A. (1971), "Geology of the Central Nimrod Glacier area, Antarctica", New Zealand Journal of Geology and Geophysics, 17 (3): 427–468, Bibcode:1971NZJGG..14..427L, doi:10.1080/00288306.1971.10421939, retrieved 2018-05-22 Myrow, Paul M.; Pope, Michael C.; Goodge, John W.; Fischer, Woodward; Palmer, Alison R. (2002), "Depositional history of pre-Devonian strata and timing of Ross orogenic tectonism in the central Transantarctic Mountains, Antarctica" (PDF), GSA Bulletin, 114 (9): 1070–1088, Bibcode:2002GSAB..114.1070M, doi:10.1130/0016-7606(2002)114<1070:DHOPDS>2.0.CO;2, S2CID 17130391, archived from the original (PDF) on 2018-05-23, retrieved 2018-05-22 Palmer, A.R.; Rowell, A.J. (1995), "Early Cambrian trilobites from the Shackleton Limestone of the Central Mountains", Journal of Paleontology Memoir, 69: 1–28, doi:10.1017/S0022336000061424, retrieved 2018-05-22 Skovsted, Christian B.; Betts, Marissa J.; Topper, Timothy P.; Brock, Glenn A. (2015), "The early Cambrian tommotiid genus Dailyatia from South Australia", AAP Memoir, 48: 1–117, Bibcode:2015ectg.book.....S, retrieved 2018-05-22 Stump, Edmund; Gootee, Brian; Talarico, Franco (2006). "Tectonic Model for Development of the Byrd Glacier Discontinuity and Surrounding Regions of the Transantarctic Mountains during the Neoproterozoic — Early Paleozoic" (PDF). Antarctica. Berlin/Heidelberg: Springer-Verlag. pp. 181–190. doi:10.1007/3-540-32934-x_22. ISBN 978-3-540-30673-3.

Illustrations

Worked examples

Example 1 — a first encounter with Shackleton Limestone

Start with the simplest possible case. Write down what Shackleton Limestone 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 Shackleton Limestone 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 Shackleton Limestone 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 Shackleton Limestone

In research: Shackleton Limestone 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 Shackleton Limestone 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: Shackleton Limestone is common in secondary-school and first-year university syllabi. It links to neighbouring topics Cambrian southern paleotropical deposits, Conglomerate formations, Dolomite formations, so understanding it makes those chapters shorter.
In everyday life: Look for Shackleton Limestone 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.

Affiliate

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

How to study Shackleton Limestone in 20 minutes

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

Frequently asked questions

What is Shackleton Limestone in simple terms?

Why does Shackleton Limestone 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 Shackleton Limestone?

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 Shackleton Limestone.