At www.yahoo.com/news/dinosurs-struggled-survive-long-asteroid-hit-19233514… … and www.yahoo.com/news/study-dinosaurs-were-declining-long-asteroid-hit-1902… … which has been widely reported on the Web and concerns a press release coinciding with publication of a paper on the subject which appears to use geochronology to say that dinosaurs were in decline before the K/T boundary event (and the Chicxulub asteroid or comet crash). This is all part and parcel of the mainstream desire to water down the catastrophism element – by sowing seeds of doubt (do we really need an asteroid strike to account for the demise of the dinosaurs).
The argument is that dinosaurs were not so numerous 5 to 10 million years prior to the event. Now, a new paper is shifting the boundaries to say they were in decline 50 million years before the asteroid hit. The paper is in April's issue of PNAS (2016) and it goes on to say they have no idea what might have caused such a decline (but I'm sure somebody will come up with an explanation soon). What about an asteroid and sediment layers forming very rapidly as of result of striking Earth and making a dent in the crust at Chicxulub. The 50 million years disappears very quickly in such an analysis. There is also the problem that palaeontologists have a small table to work from. Dinosaurs would have inhabited most of the planet – but their remains are piecemeal. It is all a bit of luck which dinosaurs are common to science and those dinosaurs that were common in the Jurassic and Cretaceous.
I'm sure that dinosaurs show a decline – but what are they looking at. Sediments laid down over millions of years or sediments that were all part and parcel of the catastrophic event? If the latter and then the decline is imaginary. If 50 million years are really involved we have a distinct problem. What would cause dinosaurs to decline without an accompanying event to push them over the edge. You could go on writing and publishing articles on such an event for years and years – and enjoy lots of speaker meetings. In the end all you would have is guesswork – and assumption (the stock in trade). An asteroid strike is terminal. Final. No arguments. An asteroid strike would also have decimated the geochronological record causing sediments in some parts of the world to form very quickly. One could compare the situation with Mount St Helens but mainstream tend to keep quiet about the laying down of vast streams of mud and debris (an instant sediment bed) which is a pity as what was learned from that volcanic explosion could be used to interpret what might have occurred at the K/T boundary event.