How about an elegant light grey suit? ..Will help you keep away the scorching Indian sun.
That's an unnamed senior Indian government official at a photo-op (source) leaning over a row of dinosaur eggs found recently from the Upper Cretaceous (about 80 million years ago according to the report) of the Narmada river valley central India.
The Narmada river flows westwards within an ancient rift zone which originated during early Proterozoic and has been reactivated to become a sedimentary basin several times thereafter. Mid-late Cretaceous was one such time of reactivation, several linear east west oriented basins forming in response to the crustal stresses generated as India wrenched itself away from Africa, then Madagascar and then Seychelles.
Mid late Cretaceous was a time of globally high sea levels. Marine incursions into these basins took place from the west, but there are fluvial (river) and lacustrine (lake) sediments also in the Cretaceous basins of central India. The recently found dinosaur eggs along with other reptilian fossils are from lacustrine and fluvial deposits preserved in the Dhar district of Madhya Pradesh.
The terrestrial Cretaceous sediments of central India have been yielding a rich trove of dinosaur and reptilian fossils. These are thin patchy deposits. Large portions of these deposits are likely buried under the Deccan basalts, entombed by lavas that began erupting around 65 mya. The deposits that do outcrop are being threatened by increased farming activities and urbanization. So, its really good to hear that the Madhya Pradesh government is planning on creating a dinosaur park which will hopefully protect at least some of these fossil sites.
Meanwhile.. I found this geological map of Madhya Pradesh from the Geological Survey of India Geology and Mineral Map series which is worth sharing.. below is a portion of the map showing western Madhya Pradesh. The red arrow indicates the general location of the Upper Cretaceous outcrops (blue) of Dhar district.
Click here for the full pdf version.
The Narmada river flows westwards within an ancient rift zone which originated during early Proterozoic and has been reactivated to become a sedimentary basin several times thereafter. Mid-late Cretaceous was one such time of reactivation, several linear east west oriented basins forming in response to the crustal stresses generated as India wrenched itself away from Africa, then Madagascar and then Seychelles.
Mid late Cretaceous was a time of globally high sea levels. Marine incursions into these basins took place from the west, but there are fluvial (river) and lacustrine (lake) sediments also in the Cretaceous basins of central India. The recently found dinosaur eggs along with other reptilian fossils are from lacustrine and fluvial deposits preserved in the Dhar district of Madhya Pradesh.
The terrestrial Cretaceous sediments of central India have been yielding a rich trove of dinosaur and reptilian fossils. These are thin patchy deposits. Large portions of these deposits are likely buried under the Deccan basalts, entombed by lavas that began erupting around 65 mya. The deposits that do outcrop are being threatened by increased farming activities and urbanization. So, its really good to hear that the Madhya Pradesh government is planning on creating a dinosaur park which will hopefully protect at least some of these fossil sites.
Meanwhile.. I found this geological map of Madhya Pradesh from the Geological Survey of India Geology and Mineral Map series which is worth sharing.. below is a portion of the map showing western Madhya Pradesh. The red arrow indicates the general location of the Upper Cretaceous outcrops (blue) of Dhar district.
Click here for the full pdf version.
interesting article...thanks for the info...
ReplyDeletei guess the Africa-India separation started ~160Ma in late Jurassic and not Mid-Late Creat!!!
Cheers!
SUB
hi SUB- yes thanks..you're right..I should have mentioned that there are earlier Jurassic basins possibly related to the break up with Africa proper.. there are successions of Mesozoic basins along the Narmada rift developed at various times .. and Mid-late Cretaceous is one phase, if one wants to relate it to an event then it would likely be the breakup with Madagascar?..
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