Fireball from Space Gave Birth to Odd, Flat-Topped Hill in Karoo

Cape Times (South Africa), February 22, 2013 | Go to article overview

Fireball from Space Gave Birth to Odd, Flat-Topped Hill in Karoo


BYLINE: Roelof Bezuidenhout

As the 45m long earth-crosser, 2012 DA14, hurtles by and in the wake of the meteor strike in Russia's Ural Mountains last weekend, it is interesting to review the damage caused by a meteorite, half the size of 2012 DA14, which smashed into the Great Karoo 250 000 years ago and blasted out a crater 640m wide and 300m deep.

The missile probably vapourised instantly from friction heat, triggering a shock wave that would have registered over maximum on the Richter scale and spewing debris for kilometres around. A dense cloud of dust is likely to have covered the whole area for at least a few months. Over centuries, the crater slowly filled with mineral-rich water which eventually evaporated, leaving a limestone fill now raised above the sparse veld.

The mudstone ridge that at first surrounded the impact zone has weathered away, leaving the harder limestone protruding above the terrain. From the air, the formation shows up as a round, white patch almost touching the Bull River, at a spot 50km south of Graaff-Reinet.

The impact site, known as Kalkkop, is one of the least-known astrological and geological curiosities in South Africa. Meteorite impact sites that have survived erosion over the millennia are extremely rare, and Kalkkop is only the third to have been positively identified in southern Africa. The others are the larger - and of the same age - Tswaing Crater (formerly Pretoria Saltpan Crater) and the Roter Kamm Crater in Namibia, which contains a 60 ton monster of iron and nickel.

The peculiarities of Kalkkop have been sporadically studied since 1943. At one time it was included on a list of drilling targets for an oil search. But the drill core taken attracted little interest and was thrown away. With it went evidence of Kalkkop's origin. Kalkkop remained just an odd, flat-topped hill in the middle of nowhere - until the early 1990s when geologists working for the Geological Survey started a more comprehensive drilling project.

The new drill core presented a profile consisting of a thick layer of lake-deposited limestone, underlayed by fragmented bedrock of the type often encountered in impact structures. …

The rest of this article is only available to active members of Questia

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items

Items saved from this article

This article has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this article

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited article

Fireball from Space Gave Birth to Odd, Flat-Topped Hill in Karoo
Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Help
Full screen

matching results for page

    Questia reader help

    How to highlight and cite specific passages

    1. Click or tap the first word you want to select.
    2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
    3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

    OK, got it!

    Cited passage

    Style
    Citations are available only to our active members.
    Buy instant access to cite pages or passages in MLA, APA and Chicago citation styles.

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

    1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

    Cited passage

    Thanks for trying Questia!

    Please continue trying out our research tools, but please note, full functionality is available only to our active members.

    Your work will be lost once you leave this Web page.

    Buy instant access to save your work.

    Already a member? Log in now.

    Author Advanced search

    Oops!

    An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.