As I near the end of my 5 weeks on the Liftboat Myrtle, I can reflect on the emotional rollercoaster that it has been being a part of the Chicxulub expedition. Our goals for this expedition were to:
1) core through the interesting climate zones within the early Cenozoic, including the Eocene when it was 7 degrees C warmer than today;
2) study recovery of life after the impact;
3) collect cores across the boundary were the impact layer formed within minutes to hours and to core deep into the peak ring of the crater to understand how impact cratering works as a geologic process, both here, and on other planets
4) take samples to look for life that evolved in the crater after the impact.
As a co-chief scientist, I constantly consider the overall success of the project. Will we accomplish these goals? Will we get enough of the right kind of rocks and downhole geophysical logs for each of the 30+ scientists in our Science Party that have competed to be a part of this project?
So to summarise my 5 weeks in a few milestones:
-Arriving on-board just in time to start downhole logging in the upper 500 m of the hole (WE WIN)
-Some difficulties getting back into the hole to start successfully coring (STRESS)
-Successfully coring through over 100 m of carbonate rocks that bury the impact crater and contain the recovery of life (WIN AGAIN)! There were windows here of serious excitement trying to figure out exactly where we were in the geologic time…not a lot of sleep as we approached critical boundaries!
-Surprise discovery of the K-Pg boundary 30 m shallower than we expected and an ensuing bet as to whether it was the actual boundary or if the boundary was still deeper in the hole (HEAD SCRATCHER)
-Discovering that in fact the top of the impact layer was shallower and thicker than expected (A WIN- specifically a bottle of single malt since we bet on it- can’t wait to collect onshore!)
-Lots of interviews with media taking care to keep the folks at home excited without saying too much (LEARNING EXPERIENCE)
-Second logging run at 700 m which itself was a roller coaster as we were down for three hours because of a blown fuse we didn’t even know existed, but then a great set of data (STRESS followed by WIN)
– The end of drill bit that required a step down to next size bit and pipe (JUST ANOTHER DAY AT THE OFFICE) and then resumption of coring at a faster rate than expected (WIN)
-Major media visit to the platform where we were able to convince skeptics that we in fact are doing science and not secretly drilling for oil (WIN)! Note oil requires burying organic matter for tens of millions of years in just the right pressure/temperature window; this spot on Earth got hit with an asteroid the size of Staten Island… no oil in the crater for obvious reasons! Also humans did land on the Moon, collected samples, and played some golf… let’s not denigrate the wins of our fellow humans with conspiracy theories, please!
-Drilling through impact breccia and into fractured basement rocks spawning lots of discussions about impact cratering processes (WIN AGAIN)!
-Wondering now what else we will find as we continue to drill (ANTICIPATION)…
So it has been quite a ride of excitement, stress, and discoveries; there are still 100s of meters to go into the crater until we reach our 1500 m target depth. Of our goals, we may have already succeeded in addressing at least parts of all of them, but we can’t stop now as we would only be scratching the surface of the peak ring. Who knows what other interesting things we will learn about Chicxulub, and impact craters generally, in the next 700 m of core!
I will be onshore for the final month of the drilling and my fellow co-chief scientist Jo Morgan is taking over. It is now my turn to follow the exciting events remotely until it is time for us all to go to Bremen in Germany and open up the cores to see them in all their glory. We will then roll up our sleeves and really get to work!
Before I go though, as with any scientific expedition, I feel blessed when I think of the people that share this few dozen meters of steel deck. The group of scientists, technicians, engineers, drillers, and officers and crew of the Myrtle, have been truly a pleasure to work with. I have learned a ton and hopefully helped folks to enjoy being a part of this history-making expedition.
Co-chief Scientist, Dr. Sean Gulick