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horsetuna t1_j4ts8uz wrote

I don't know much about why they thought the peninsula formed. The current crater from the chixulub impact is half under the land and half under the sea, and does not seem to follow the coastline as it is today.

Mostly what convinced people was the timing and size. Before the Alvarez team (father and son) found the iridium in the KT boundary, there wasn't any evidence that there was a meteoric strike at the right time of the right size. After they found the iridium, they looked for other records from mining/gas companies, as people wanted the smoking gun .. the crater itself.

They calculated how big a bolide would be needed to coat the earth in such a way with this amount of iridium and then calculated the size of the crater, as well as the age.

The crater had actually been known for a while but the company that did the surveys wasn't keen on sharing their info due to competition concerns (not specifically about the crater iirc)

Finally once the crater was found, dated and confirmed it was accepted more or less. Better climate modelling showing the extent of the conditions also helped the case

Many think it wasn't the ONLY factor though. But a contributing one. The last straw that broke the camels back so to speak.

For instance the Deccan traps in India is the remains of a massive flood basalt that occured around the same time and likely contributed to the situation with the bolide (some claim the impact caused the volcanic eruption, the shock waves converging on the far side of the planet where India would have been at the time. But less evidence for that).

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CrustalTrudger t1_j4uqowa wrote

> Finally once the crater was found, dated and confirmed it was accepted more or less.

This ignores a pretty active literature stream that has persisted since the impact hypothesis was proposed (and which continues to this day) that questions whether this was the cause (e.g., McLean, 1985, Courtillo & Cisowski, 1987, Pope, 2002, Keller et al., 2004, Fastovsky & Sheehan, 2005, Keller et al., 2020, etc.).

> some claim the impact caused the volcanic eruption, the shock waves converging on the far side of the planet where India would have been at the time

This is generally not what is argued for. What has been suggested is that the impact may have triggered a large pulse of Deccan Traps volcanism, but the timing of the start of Deccan Traps volcanism is demonstrably before the impact (e.g., Renne et al., 2013, Schoene et al., 2014, Renne et al., 2015) but timing of the main eruptive pulse remains controversial, i.e., it may have occurred sufficiently after the impact to be unrelated (e.g., Sprain et al., 2019).

> But less evidence for that

This is debatable, viable kill mechanisms tied to either event are pervasive in the literature (as are people pointing out issues with the alternative kill mechanism(s)). Arguably, the idea that neither the Deccan Traps nor the Chicxulub impact alone would have caused the extinction, but that the occurrence of both in short succession was enough to start the cascade is becoming closer to a consensus view (e.g., Petersen et al., 2016, but also the Renne et al., 2013 and Schoene et al., 2019 papers cited earlier). Similarly, there are suggestions that the K-Pg extinction was relatively protracted, perhaps occurred in pulses, and started before the impact, but with a pulse in extinction linked to the impact (e.g., Tobin, 2017)

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cakedayCountdown OP t1_j4uqsgd wrote

This is great. Thank you so much.

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horsetuna t1_j4wchmy wrote

You're very welcome. Other people have also given some good ideas as well as more detailed explanations.

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No_Perspective4340 t1_j69dmrl wrote

This and other answers speak to something much broader about the sciences and really, most branches of academia.

It's one thing for a potentially game-changing fact or new data to be identified or noted. The actual conclusions based on said data can take decades, or maybe reach no resolution at all, or the conclusions may change based on new analyses, etc.

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