Saturday, December 7, 2013

Strange Woman Abroad: Chongqing Ichnology Conference - The Lotus Tracksite

Well, Dear Readers, it's time to resume the saga of our 2012 Chongqing Ichnology Conference and related field trips. We visited the Yangqing National Geopark Tracksite (we made a return trip in September 2013, but that is a story for another time), and the Shandong area tracksites within the quarries. Now we were whisked away from the cool dry climate of north-central China to the southern coastal region of Chongqing. This would be the last field work we did before the conference on November 29.

In northeastern BC I've had the privilege of working on some spectacular paleontology sites with glamorous scenery that inspires one to run through alpine meadows singing. The Lotus Tracksite is one of those sites. Situated outside of the city of Chongqing, it gives off a sense of idyllic rural peacefulness.
"The hills are alive with the sound of footprints! Lalalalaaaahaaaa!" (This is why I am a scientist and not a singer.) Mountain scenery of the Lotus Stockade Tracksite.
For the next four days, the bus would drive us to the rural center, and then we would walk along a path that went over brook and field.

We followed the path to the farmhouse in the upper right corner of the photo.

Laura Pinuela and Martin Lockley.

Lovely terraced farms.

Babbling brook with sediment from a recent rain.

A completely different style of growing crops than I was used to seeing growing up in southern British Columbia farm country.

I was not brave enough to try one of the fresh spicy peppers seen on this pepper plant. I hang my head in shame. (No one else tried one either, so I am in good company!)
Our party reached the farmhouse, but that was not the end of the trek. Oh no: we had to transport ourselves (and our field gear) from the base of the cliff to a natural fissure using a cement stairway.

Daniel Marty and the resident farm ducks. These ducks spent a great deal of time free-ranging in the fields. They are also a possible modern analog for a webbed bird footprint from the Cretaceous, named Uhangrichnus.

Our brief reprieve at the farmhouse. Lida Xing (left), Martin Lockley (right).
Can you see the tracksite from here? If I were going to hide from raiders, this would be the place.
Martin actually counted the steps: there are approximately 900 steps in the staircase. This is where I experienced a slight ping of culture shock, because around noon and in the afternoons we would see elderly people slowly walking up and down the entire stairway. They were doing this for exercise. Coming from a culture where everything is in walking distance yet people drive less than a kilometer to get a bag of potato chips, this impressed me.

So many steps...

The Lotus Tracksite from the stairs. Almost there!
If it wasn't for the staircase, I could not see any easy egress or regress to the Stockade. It was a perfect defensive post against raiders.

As the Lotus Stockade is now a heritage tourism destination (thanks to the work of Lida Xing), there were visitor friendly additions to the actual site (including the stairs). Wooden boardwalks are installed so that people can view the tracks without stepping on them. As the derelicts that ichnologists are, the first thing we did was physically explore the track surface.

Approaching the tracksite.

Wooden barricades keep distracted paleontologists corralled.
The Lotus Stockade has a fascinating history. The people who took shelter there 700 years ago noticed the large ornithopod tracks and the large-scale dessication features. They arrived a very astute explanation for the presence of these odd shapes: the ornithopod tracks were described as preserved impressions of lotus blossoms. One of the fascinating parts of ichnology is discovering all of the cultural explanations for footprints, and this is one of my favorites. Lida did a wonderful artistic interpretation of the story, and it became one of the logos for the Ichnology Conference.

The interpretation of ornithopod tracks as preserved lotus impressions does not require a large leap in imagination. Check out the original image here.

Now it was time to get to work. As these tracks are currently the subject of in-progress and in-press papers, I won't show too many of the details that are going to occur in said papers. However, there are two surfaces that we had to document in three days: the upper ornithopod track layer, and the lower bird layer.

The upper ornithopod surface, viewable through a plexiglass floor. Us delinquent ichnologists had special permission to crawl all over the surface.
We split into two teams. Rich, Martin, Laura, and I took the lead on the bird layer, while Daniel, Matteo, Hendrik, and Julien worked on the ornithopod layer. The two teams had slightly different procedures, but both ended with two large plastic tracings that matched up between the layers beautifully. Lida bounced between Team Ornithopod and Team Bird (my affectionate names for the groups - we were all one happy ichnology team) making sure that we had everything we needed for a three-day session of mass data collection. He also made sure we were fed: a constant supply of snacks were made available.

Here's how Team Bird tackled a several square meter surface that contains over 200 footprints (218 according to my field notes.) First, we found a very distinct footprint with a clear digit III preserved. The end of digit III was the anchor point for the next step. Second, we established a 1 meter by 1 meter grid system along the surface. We established the grid using fairly old-school techniques: a compass, a meter stick, and chalk.

Next, we physically gridded the entire track-bearing surface. We went through a great deal of chalk! We saved our welder's soapstone pens for the next step of physically outlining each and every footprint we could see on the surface. Establishing the physical grid took about half a day (we checked, double-checked, and triple-checked for repeatability) while the outlining of the prints took about another half of a day. It is a long process, but it makes the data collection all the more simple.

Next, we labeled each footprint according to the grid square in which it occurred (e.g. track B10-1, A2-7, etc.) Each print was photographed from multiple angles for future digitizing work, as well as each individual grid square. After the tracks were labeled and individually photographed, physical measurements were collected (I rarely collect data from photographs if I have the original specimens at hand.)

Rich McCrea (foreground) of Team Bird photographing gridded squares while Martin Lockley paints latex on a specimen for replication. Team Ornithopod is in the background.
Team Ornithopod tracing the upper surface.
We were all quite amazed when we found out that we didn't have to hike all the way back down to farmhouse for lunch. A hot lunch was brought up to us! Salted pork, cabbage and hot peppers, rice, and stewed pumpkin! You can see from the photos that we are all in our cold weather gear, and a hot lunch was most welcome.

A hot lunch at the Lotus Tracksite.
Team Bird spent the bulk of their time physically measuring prints and taking photos. It wasn't until November 28 that we joined the tracing party.

The final step: tracing the surface onto plastic sheets. Not only did we trace on the prints on the plastic map, but we traced on the corners of the grid squares for reference.

Other researchers and conference attendees arrived during our three day session at the Lotus Track, which allowed for more eyes on the surface.

Team Bird was finished the documentation of the lower surface late in the afternoon of the 28th. It's an odd feeling to be finished documenting a surface. I always feel as though I should be doing something else, but we had done everything we could do in the time frame available. We were done. Team Ornithopod continued into the evening, but they too were finished on the 28th. Now all we had to do was to put our finishing touches on our presentations and switch to conference mode! The conference was fascinating, and I am pleased to say that my presentation on the multivariate analysis of Mesozoic bird footprints was very well received.

The traced plastic maps, all bundled up and ready to head to the lab for interpretation.
My patience was well rewarded! I had finally seen and documented bird footprints! Not only that, but I had seen bird footprints in an area steeped with history. My co-authors and I are working on getting the paper that analyzes these prints ready for submission. Stay tuned!

That's it for now!

SW out.

2 comments:

  1. Love your report.
    This place seems amazing..

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    Replies
    1. Thank you! The Lotus Site has been etched in my mind as one of the icons of China's blend of paleontology and cultural heritage.

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