Meghalayan Days
From my years working at the Geology Library at the University of Texas (for Dennis Trombatore, a wonderful person, R.I.P.) I have a smattering of knowledge in the area. Aside from hiding in the stacks reading fascinating and fusty old books (as we all did) I took some classes and then got a bit obsessed with the Roadside Geology series of books when I lived in the Southwest. (Halka Chronic fans unite!)
Someone put a copy of “Rancho La Brea: A Record of Pleistocene Life in California” from 1949 in my little free library so I am plugging through it. It is not telling a compelling story with great writing, but I love it anyway because it is a key to all the knowledge they had at the time, systematically arranged. The book goes through the history of its discovery, the geology and stratigraphy of the area, a catalogue of all the kinds of creatures and plants found, and a beautiful bibliography and index. I have a million questions and became suddenly an absolute hound searching for tar pit facts.
The wild thing you will instantly notice is this is pre “Continental Drift” ie plate tectonics, and pre radiocarbon dating. So everything is relative ages via stratigraphy and who knows how it all happened. (A bit handwavy on how or why the climate changed for example).
People had noticed the bones in the bubbling asphalt but not really grokked that they were not just cows and coyotes and deer but were instead from the Pleistocene. (We now know they were gathering bones from around 50,000 years ago till the present.)
I was wondering what the oldest tar pits are. Still the Pleistocene, though much older than La Brea! The oldest might be the Binagadi Asphalt Lake pits in Azerbajan, at 96–120 thousand years old.
Can you extract DNA from the teeth from the tar pits? Someone has thought of this and written a neat paper! https://pmc.ncbi.nlm.nih.gov/articles/PMC3936381/ (Summary: probably not.)
I remember being a bit disappointed when I heard that the proposal to start a new geologic time division for the Anthropocene (1952 – ) had failed. But I never thought to look at what changes had been accepted! OMG! So many changes! I learned the word “Eonothem“! (And will be looking for some occasion to use it.) So, I learned the more recent eras as the Cenozonic (divided into Paeleocene, Eocene, Oligocene, Miocene, Pliocene) then Quaternary ( Pliestocene, Holocene (now)). Y’all there are so many new stages in the Cenozoic! Is the whole idea of “stages” new? Help! I feel my brain itching to memorize it all. But nowadays I don’t just automatically remember new facts and would have to work at it. (Unlikely).
Anyway, we are now in the Meghalayan Age. In case you were wondering! It started around 4200 years ago, the catchily named 4.2 kiloyear event, which seems to be hotly disputed but which is also very interesting to read about!
Reading older science books can be especially mind expanding. You get a glimpse of the state of knowledge of a particular time that is otherwise hard to grasp. Maybe tomorrow I will go up on the hallway book ladder and get down some old Encyclopedia Brittanica volumes to see if there is an article on the tarpits. I can’t remember if I have the 11th edition or the 12th.
(It is the 11th, in 1911, and Rancho Labrea is mentioned in the Los Angeles entry as containing the Salt Lake Oil Fields – nothing about the tar pits .)