“Hidden ‘Jurassic World’ Buried Underneath Australia”

Guest geology/geophysics drive-by by David Middleton

H/T to Dr. Willie Soon

Cool story, stupid headline…

Scientists Found a Hidden ‘Jurassic World’ Buried Underneath Australia
The subterranean remains of 100 volcanoes formed some 180 million years ago were detected under a major petroleum hotspot.

By Becky Ferreira
Aug 14 2019

A trove of 100 Jurassic-era volcanoes has been discovered deep underneath a petroleum-rich region of central Australia, according to a new study.

The ancient volcanoes formed between 180 and 160 million years ago, just as the prehistoric supercontinent Gondwana—of which Australia was once a part—began to break apart. For millennia, this underground volcanic landscape lay buried underground, eluding detection.

[…]

These deposits have been a hotspot of oil and gas production since the 1960s, and the region is currently Australia’s largest onshore source of hydrocarbons, which made the new find particularly surprising.
According to the study authors, finding such an epic volcanic landscape in an area that has already undergone substantial data collection “raises the prospect of other undiscovered […] volcanic provinces both in Australia and in other continental areas worldwide.”

Some 1,400 oil wells have been drilled in this area over the past half-century, some of which turned up igneous rocks that suggested ancient lava might be preserved in the sediment.

[…]

Vice

There’s a “Jurassic world” buried under just about every Cretaceous and younger “hotspot of oil and gas production” in the world… The Jurassic is almost always below the Cretaceous… unless the beds have been overturned, it’s in an overthrust belt or it’s Jurassic-aged mobile salt. The Gulf of Mexico features a Jurassic desert buried 20,000′ below the seafloor, places where there are 1,000’s of feet of Jurassic salt above Cenozoic “rocks,” and mysterious volcanoes too… Plus… If the Gulf of Mexico ever froze, there would be enough ice to replace the Greenland ice sheet… That’s like eleventy gazillion Olympic-sized swimming pools.

The headline may have been stupid, but, the science is way cool! They were able to make fairly detailed maps of what appear to be volcanic features by integrating seismic, gravity and well data…

IMAGERY FROM THE GONDWANA RESEARCH PAPER. IMAGE: UNIVERSITY OF ABERDEEN/UNIVERSITY OF ADELAIDE

A pre-print full version of their paper can be accessed here.

The “Warnie volcanic province” is actually in between two hydrocarbon basins…

The Cooper and Eromanga Basins of South Australia and Queensland are the largest onshore hydrocarbon producing region in Australia. Igneous rocks have been documented infrequently within end of well reports over the past 34 years, with a late Triassic to Jurassic age determined from well data. However, the areal extent and nature of these basaltic rocks were largely unclear. Here, we integrate seismic, well, gravity, and magnetic data to clarify the extent and character of igneous rocks preserved within Eromanga Basin stratigraphy overlying the Nappamerri Trough of the Cooper Basin. We recognise mafic monogenetic volcanoes that extend into tabular basalt lava flows, igneous intrusions and, more locally, hydrothermally altered compound lava flows. The volcanic province covers ~7500 km2 and is proposed to have been active between ~180–160 Ma. We term this Jurassic volcanic province the Warnie Volcanic Province (WVP) after the Warnie East 1 exploration well, drilled in 1985. The distribution of extrusive and intrusive igneous rocks is primarily controlled by basement structure, with extrusive and intrusive igneous rocks elongate in a NW-SE direction. Finally, we detail how the WVP fits into the record of Jurassic volcanism in eastern Australia. The WVP is interpreted as a product of extension and intraplate convective upwelling above the subducting Pacific Slab. The discovery of the WVP raises the possibility of other, yet unidentified, volcanic provinces worldwide.

[…]

Hardman et al., 2019

Just because I expect this to be mentioned in numerous comments: No! These are not the hydrocarbon source rocks of the Cooper Basin. The Cooper Basin is much older and lies unconformably below the Eromanga Basin.

Kuske et al., 2016

Nor are they the source rocks for the younger Eromanga Basin.

Kuske et al., 2016

How could a volcanic field get between two sedimentary basins?

The San Francisco Peaks volcanic field of Arizona might just be a modern analogy for the The Warnie Volcanic Province. 10’s of millions of years in the future, parts of it might just be covered by a future sedimentary basin, sandwiched between two basins like the Warnie Volcanic Province.

Zion National Park Project Forever

References

Hardman, Jonathon P.A., Simon P. Holford, Nick Schofield, Mark Bunch, Daniel Gibbins, “The Warnie volcanic province: Jurassic intraplate volcanism in Central Australia”. Gondwana Research, Volume 76, 2019,
Pages 322-347, ISSN 1342-937X, https://doi.org/10.1016/j.gr.2019.06.012.

Hardman, Jonathon, Simon Holford, Nick Schofield, Mark Bunch, and Daniel Gibbins. 2018. “The Warnie Volcanic Province: A Jurassic Volcanic Province in Central Australia.” EarthArXiv. December 12. doi:10.31223/osf.io/9zmty.

Kuske, Tehani J., Lisa Hall, Tony Hill, Alison Troup, Dianne Edwards1, Chris Boreham and Tamara Buckler. “Source Rocks of the Cooper Basin”. Search and Discovery Article #10829 (2016)**


Advertisements

42 thoughts on ““Hidden ‘Jurassic World’ Buried Underneath Australia”

  1. Gondwana was still basically intact 180 to 160 Ma. Australia was rotated about 90 degrees from its current orientation, so that its present south coast was attached to eastern Antarctica, which lay farther north than now. New Zealand bordered Australia. India and Madagascar joined northern Antarctica and southeastern Africa. Eastern South America was united with western Africa.

    Marsupials could and did travel between Australia and South America. Australia was last bit to rift free from Antarctica. They remained conjoined even after the end of the Mesozoic Era, although Oz moved to its present orientation (but not position) by the Late Cretaceous, as Antarctica rotated to move farther south.

    The Indian Plate’s race across the Indian Ocean to collide with the Eurasian Plate, building the Himalayas in the smash-up was at high speed (in geologic terms). At the time of the K/Pg Mass Extinction Event, it was over the Reunion Hotspot, which transit cause the Deccan Trap flood basalt eruptions, thought by some to have contributed to the non-avian dino-dooming MEE.

    • John Tillman
      August 18, 2019 at 2:35 pm

      Thanks for the quick geologic summary which I think even Ian Plimer would be impressed with.
      So…did the impact cause the Reunion hotspot to (re)activate or is it just a rough temporal coincidence of sorts. Who or what did in the dinos?

      • The impact didn’t cause the hotspot.

        It was already there. Strange as it seems, it appears that the Deccan Traps didn’t cause the dino doom, plus marine reptiles, ammonites, etc.

        It’s all down to the Yucatan impact.

        • It is rather odd, but despite a number of younger LIP:s not one after the CAMP c. 200 mya ago has caused a major or even minor extinction. And there has been some huge ones. Karroo-Ferrar, Paraná-Etendeka, Kerguelen, Deccan, Ontong Java, North Atlantic-Iceland, Ethiopia-Afar, Snake River.

          The Siberian Traps and CAMP are the only LIP:s credibly connected to extinctions, what made them unique? And, no, erupting through organics-rich sediments is not the explanation. That applies to the North Atlantic LIP as well.

          • PS

            It strikes me that not everybody knows what a LIP is. It stands for Large Igneous Province, which is an enormous outpouring of basalt, typically millions of cubic kilometers, all erupted during a geologically quite brief interval.

            Eruptions typically occur through long fissures, and Iceland is the only place where this kind of eruption occurs today, though on a relatively small scale.

      • Yes, in Early and Middle Jurassic time, only Laurasia had separated from Gondwanaland across the rifted Central Atlantic.

    • So far Ozraptor, fom West Oz, is known only from a partial left shin bone.

      More Queensland Rhoetosaurus material is being discovered as time goes by. Its affinities are controversial, but probably lie, no surprise given its age and location, outside the more derived Neosauropoda.

      • On the outer limits of the Mesozoic world, Oz had a distinctive mix of dinos, fairly diverse, thanks to a variety of polar, subpolar and temperate environments, possibly just poking into the subtropics. Leaving out some suspected dubious names.

        Saurischia

        Therapoda

        Ozraptor, Middle Jurassic
        Kakuru, Early Cretaceous
        Rapator, Early Cretaceous
        Timimus, Early Cretaceous
        Australovenator, Late Cretaceous

        Sauropoda

        Rhoetosaurus, Middle Jurassic
        Austrosaurus, Early Cretaceous
        Diamantinasaurus, Late Cretaceous
        Wintonotitan, Late Cretaceous
        Savannasaurus, Late Cretaceous

        Ornithischia

        Ornithopoda

        Leaellynasaura, Early Cretaceous (possibly a more basal ornithischian)
        Qantassaurus, Early Cretaceous (ditto; both polar dinos)
        Galleonosaurus, Early Cretaceous
        Atlascopcosaurus, Early Cretaceous
        Diluvicursor, Early Cretaceous
        Muttaburrasaurus, Early Cretaceous
        Fostoria, Late Cretaceous
        Weewarrasaurus, Late Cretaceous

        Thyreophora

        Kunbarrasaurus, Early Cretaceous
        Minmi, Early Cretaceous

        Cerapoda

        Serendipaceratops, Early Cretaceous (probably not a ceratopsian, which were most likely restricted to the Northern Hemisphere, but of some other ornithschian clade)

        With the continuing break up of Pangaea during the Cretaceous, the globally fairly uniform Jurassic dino fauna took on distinct continental and island differences.

    • Theropods are also known from Chatham Islands. Zealandia was the easternmost part of Australia back then. Though these are Late Cretaceous.

      • Wow. What are the odds of that, on such a small area?

        The two main islands also have a scattering of dino fossils from latest Jurassic to end Cretaceous.

        And of course NZ is blessed with the squamate-related tuatara, the only surviving member of its order, which flourished in the Late Triassic and Early Jurassic.

  2. Growing up in AZ I was always fascinated by the escarpment as one drove north from Phoenix. Could you put a pointer to the AZ cross section so that one could enlarge it some?

    • We have the set of four cross sections framed, hanging in our home office. The posters were about $5 each from various national park bookstores.

  3. We do need continuous monitoring of the volcanic field under Antarctica, lest we are told we need a global carbon tax based on lack of data.

  4. Well it’s not our place to hog all this geological wonderment as somebody has to keep the global lights on-
    https://www.msn.com/en-au/news/australia/australia-is-third-largest-exporter-of-fossil-fuels-behind-russia-and-saudi-arabia/ar-AAFZ1fg
    Meanwhile the Labor Opposition who wanted to introduce a carbon tax in the past and bangs on regularly about climate change faces up to where its redistributive bread is buttered-
    https://www.msn.com/en-au/news/australia/labor-backs-resistance-to-coal-mine-ban/ar-AAFWJXq
    Never come between pinkos and a bucket of money so adios Greenies and welcome to the bipartisanship.

  5. I hope Australia’s lunatic greens don’t hear about this. They’ll be wanting to stop all mining to “preserve” the volcanoes. Don’t scoff – when it comes to our green loons, we’re talking gold-medal class.

  6. I’m familiar with some of the gas fields in the Cooper Basin. What I found unusual was the high BHT of the wells in the Moomba field. These wells, with a depth of around 10,000′ would have bottom hole temperatures in the 380 degrees F and a few as high as 400 degrees. This was double the temperature gradient I was used to seeing in the US.

    Maybe they were sitting on top of a volcano?

    • SMS
      August 18, 2019 at 8:37 pm

      Global warming has clearly reached new depths. We’re all doomed!

  7. 10’s of millions of years in the future, parts of it might just be covered by a future sedimentary basin

    In the AOC future, the Earth is fried in 12 years so it doesn’t matter.
    In the Carlin future, the Earth shakes humanity off like bad case of fleas.

    The future is the multiverse of possibilities driven by probability… very much like a Schrodinger Wave Function, but entangled on a vast scale. The past is frozen, observed, a quantum coherence collapsed. Unalterable by the flow of entropy and energy we call time. The cosmologists who write and talk of multiverses in past have their arrow of time reversed… sign error in their math.

  8. Wait a minute… did some cane toad toking roo rustler actually name the basin “eromanga”? As in Japanese for “porn comic”?

    • Probably not.

      “The name of the town Eromanga goes back as far as about 1860. The name is thought to have come from an Aboriginal word that means “hot gale plain” or “windy plain”, though the language and dialect is unknown” : wiki

    • My former father-in-law actually came from Eromanga. In view of kate’s post, maybe that should read “was born in Eromanga”?! As far as I know, he didn’t speak Japanese.

  9. David, you put a smile on my face this morning

    I haven’t heard the use of “eleventy” or “eleventeen” since I was a youngster and early teen when my grandfather would use it. It was used as a descriptor of a pretty good bit without a quantifiable amount.

  10. The original article needed an editor:
    Second paragraph:
    “For millennia, this underground volcanic landscape lay buried underground, eluding detection.”
    David—Clear review of the geology–TKS

  11. Australia has mostly been geologically stable for a very long time and has some incredibly old landscapes.
    One of my favorites is the Murchison River gorge in WA. At first it looks like a run-of-the-mill canyon, eroded by a smallish river in Ordovician sandstone, but when you look closer you will find remnant Cretaceous limestone down in the gorge.

    Apparently the gorge was originally formed by a river running north from central Gondwana sometime back in the Triassic or Jurassic, then came an Early Cretaceous transgression and the sea covered the landscape with limestone, including the gorge. Then from the Late Cretaceous the seas retreated, the limestone was eroded away, and finally a new river re-dug the same canyon cleaning out most, but not all, the limestone.

    And near Adelaide you can find glacially striated rocks, but not striated during the current glacial age, but during the previous one c. 300 million years ago.

    Or Tunnel Creek in Kimberley, where you can walk along an underground river right through the Napier Range, which is actually a Devonian Barrier Reef that goes round much of Kimberley.

    Who knows, in another 100 million years, those Jurassic volcanos will perhaps have been exhumed again?

  12. Can you recommend to me one or more geology text books that I could read to educate myself in general geology, tectonics and the rearrangement of both continents and ocean circulation pathways? Something preferably written without recent CO2 revisionism so explaining the actual geological processes? Do such books exist that are accessible to someone with a science background but not geology? Thanks!

        • I love going through my old textbooks looking for global warming and ocean acidification… Because this is what I find…

          Suggestion that changing carbon dioxide content of the atmosphere could be a major factor in climate change dates from 1861, when it was proposed by British physicist John Tyndall.

          […]

          Unfortunately we cannot estimate accurately changes of past CO2 content of either atmosphere or oceans, nor is there any firm quantitative basis for estimating the the magnitude of drop in carbon dioxide content necessary to trigger glaciation. Moreover the entire concept of an atmospheric greenhouse effect is controversial, for the rate of ocean-atmosphere equalization is uncertain.

          Dott, Robert H. & Roger L. Batten. Evolution of the Earth. McGraw-Hill, Inc. Second Edition 1976. p. 441.

          FORECASTING THE FUTURE. We can now try to decide if we are now in an interglacial stage, with other glacials to follow, or if the world has finally emerged from the Cenozoic Ice Age. According to the Milankovitch theory, fluctuations of radiation of the type shown in Fig. 16-18 must continue and therefore future glacial stages will continue. According to the theory just described, as long as the North and South Poles retain their present thermally isolated locations, the polar latitudes will be frigid; and as the Arctic Ocean keeps oscillating between ice-free and ice-covered states, glacial-interglacial climates will continue.

          Finally, regardless of which theory one subscribes to, as long as we see no fundamental change in the late Cenozoic climate trend, and the presence of ice on Greenland and Antarctica indicates that no change has occurred, we can expect that the fluctuations of the past million years will continue.

          Donn, William L. Meteorology. 4th Edition. McGraw-Hill 1975. pp 463-464

Comments are closed.