Landslides In The Canal

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Culebra Cut

A few weeks ago, when we were driving to one of our dig sites, we noticed a dip in the road that hadn’t been there the previous week. When we returned to the site the next week the dip was lower by at least six inches. The following week I decided driving down that road was not in our best interest but we wanted to investigate. We were able to document cracks and fissures that were several feet long and 4-12 inches wide. The next week there were men surveying the area and the week after that there were excavators and backhoes. I had read about the massive landslides during the construction of the canal and was aware that due to the geology of the area they are an ongoing problem. It was fascinating and I have to admit a bit disconcerting to watch the progression of the landslide and the remedial measures that were taken in response. I was so intrigued I did a little bit of research.


Landslides have always been a problem in the Panama Canal, most notably in the 13-km long section at the southern end of the canal known as the Culebra Cut (also known as Gaillard Cut). The special wonder of the canal is Culebra Cut. It cuts through the continental divide and is the high, hard rock basaltic slopes and the lower, soft shale/clay slopes of the Cucaracha and Culebra Formations that can be seen in picturesque photos of the canal. All the rain and humidity softens the shale into mud and clay. The instability of the mud and clay results in continual landslides. David McCullough in “Path Between The Seas”, his famous book about the building of the Panama Canal, states that all technical problems were small compared to the slides in the cut. Workers on the canal would arrive in the morning and months of digging, as well as equipment, would be completely wiped out by thousands of cubic yards of dirt and rock from slides. The massive slides in the cut also played a big part in the French Canal Company’s inability to complete the canal.
In 1915 the second year of operation, the canal was hit with two major landslides that struck simultaneously. Both the east side and west side of the Culebra Formation slid, resulting in the closure of the canal for seven months. In 1986 a geotechnical advisory board was formed after a major reactivation of the East Cucaracha slide encroached into the navigational channel of the canal and caused a closure of twelve hours.
In 1988 a report was issued by Luis D. Alfaro on the risk of landslides in Gaillard Cut. He researched all of the slide events that were documented up to 1986, thirty-one in all. In his report he suggests dividing the cut into zones of relative uniform geological environments to help monitor and document movement. We use these zone names at our dig sites. Today the slopes are monitored constantly through instrumentation and field inspections so remedial measures can be implemented if movement is detected.

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Culebra Cut

The good news for us is that there is now a newly scraped-clean excavation site for us to investigate for fossils. We went there twice last week and discovered shark teeth, croc teeth, and a bunch of invertebrate fossils. image

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Fossil Friday 8/28/15: A Fossil Fruit and its Tree

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For today’s Fossil Friday, we have two plant fossils belonging to the genus Parinari in the family Chrysobalanaceae. Paleontologists always get excited when they find fossils from multiple parts of an organism, like finding the jawbone and vertebrae of a mammal, or in this case, the wood and fruit of the same tree. Continue reading

Panama Trip and Squirrel Fossils

As the other interns have previously stated, our trip to Panama over Spring Break was a huge success! Here’s my take on it:

Panama City was an amazing place to visit and I thoroughly enjoyed exploring the city. My favorite part however was the time spent in the field. I mostly spent my time at Las Cascadas. Many cool fossils were found (protoceratid skull, snake vertebrae, horse teeth, and many more) and although it was hot we had a great time. I thoroughly enjoyed myself. I also was able to explore a few marine sites and find various crab and shrimp fossils which was really fun and different for me. Below are some pictures from the trip.

Nathan doing what he does best!

Nathan doing what he does best!

Continue reading

Cleaning up after spring break

And we’re back! A ton has happened since our last post. A huge group of our scientific partners at the University of Florida spent a week helping us collect fossils in Panamá. It was a wild time, with many folks downing Gatorades to stay hydrated in the blazing afternoon sun. Our combined efforts led to many fossil finds!

Jeremy with his humerus at Centenario 2 of the Cucaracha Formation

Jeremy with his humerus at Centenario 2 of the Cucaracha Formation

Anyhow, we are picking up where we left off. Last time, I described the heavy lifting we did to clean off one of our fossil localities and increase productivity. After we moved all of that sediment, Jeremy found the distal end of a humerus, possible from a fossil rhinoceros! We’ve continued down this path, moving to a new exposure of the Cucaracha Formation.

We just finished up a two-day project to revive our Centenario 6 locality – a fossil collection site where previous researchers have found unique fossils crucial to our understanding of American biogeography. The effort was literally massive. We must have busted up and shoveled nearly one thousand pounds of rocks and sediments with our rock hammers and pickaxes.

When we started...

When we started…

In order to continue finding fossils, you have to work to expose layers where bones are most-concentrated – a result of the environmental conditions where the sediment was being laid down millions of years ago.  This unit (Cucaracha, ~19 Ma) has produced incredible finds, including part of a jaw from a “bear-dog This a carnivorous mammal that originated in the “Old World”, and an Antracothere, which is an artiodactyl ungulate closely related to hippos and which is a sister taxa of whales. These fossils are critical clues, not only because fossil carnivores from this period are incredibly rare, but also because both of these fossils strongly link the mammals living in Panamá during the Miocene to those living contemporaneously in North America. The more evidence we find, the better our picture of Panamá and its role in the relationship between North and South America before the closure of the isthmus. Also, we’re looking to find some monkeys to better complete the picture.

Our newly restored locality!

Our newly restored locality!

Stay tuned for more! And Go Gators!

Panama!

…Aaand we’re back!
PCP-PIRE intern Justy Alicea ready to be lifted to the jungle canopy.

PCP-PIRE intern Justy Alicea ready to be lifted to the jungle canopy.

After over a week in Panama, we are back in Gainesville, a little tanner and a little wiser. We learned a great deal on this trip and had a great time along the way. We were up at sunrise, worked as giant freighters passed up and down the canal all day and got to know Panama City and each other a little better.

The peaceful Sloth. One of the many locals encountered on our trip.

The peaceful Sloth. One of the many locals encountered on our trip.

We traveled all day Saturday, but we officially started the trip off on Sunday with a tour of the jungle canopy, where we saw iguanas,  monkeys and sloths, the group favorite. They were incredibly cute. We all wholeheartedly agreed we needed sloths in our lives. We then went to Punta Culebra, where we were able to get up close with local starfish, sea turtles, pelicans and rays.

The week itself was all work. We woke up and got ready to meet at 630 for breakfast, piled into a taxi van to the Smithsonian Tropical Research Institute (STRI) by 7, gathered equipment and field trucks, and drove to the canal. We were out in the field by 9. We’d spend all day digging, taking lunch around 12 and back at it until 3. Then we’d all jump back in the trucks covered in dirt and sweat and drive back to STRI to drop off our equipment, jump back in the taxi van, and be back at the hotel by 430. We’d all go shower and meet back up by 630 for dinner, where we’d go as a big group or break off into smaller groups depending on food preferences.  We hung out together after dinner and then be in bed in time to do it all over again the next day.
Shrimp claw. You can just make out the pincers on the left side.

Shrimp claw. You can just make out the pincers on the left side.

We found a lot of really nice fossils throughout the various localities we worked, from plants to sharks to horses and rhinos. It was intense, often heavy work. By noon the temperature was in the 80s-90s and if there was no breeze or cloud cover along the canal, fatigue set in quick. I almost learned the hard way that not even water is enough for dealing with that kind of heat and we kept electrolytic drinks handy at all times.
Some of the PCP-PIRE Spring break cohort in action.

Some of the PCP-PIRE Spring break cohort in action.

We ended the trip with a visit to the newly opened BioMuseo on Friday and a walk around the old Spanish ruins of Casco Viejo on Saturday. The small, modern museum was great. Highly interactive, artistic and informative, the museum had some well designed halls. The “Panama-rama” and the great biotic interchange halls were especially impressive and they left a sense of wonder and drama about the impact of this thin stretch of land connecting 2 continents on the world. It perfectly summed up the mark this trip left on all of us.

Adventures in Panama!!

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Dawn, Justy, Me, Andrea, and Will

It’s been a little more than a week since my last blog, and boy a lot has happened… Last week I and another 14 participants from the Florida Museum of Natural History visited Panama for spring break. Our goal was to extract fossils from the canal and gain experience in the field.

Sunday, March 1

Our first day in Panama we woke up early to visit the tropical canopy of Parque Natural Metropolitano, and use the crane access system to propel us towards the canopy of the trees. Nathan, Chris, Victor, Mike, aOLYMPUS DIGITAL CAMERAnd I were the first to ascend; at the tree top we could see in the far distance the whole of Panama City, we saw the never ending race of the skyscrapers reaching towards the heavens. We also saw a sloth peacefully sleeping in the branches, a flock of toucans flying as the wind, and beautiful blossoms covering the canopy. When we reached the ground we went for a hike and saw howler monkeys playfully jumping from branch to branch in the tropical forest.  We ended the day at Punta Culebra where we saw the sunset in the Pacific.

Monday, March 2

We spent most of Monday’s morning at the offices of STRI filling out paper work for our access to the canal as well as transportation. During the afternoon we headed towardOLYMPUS DIGITAL CAMERAs the canal where we met the field interns (Jeremy, Sophie, Adam and Sonia) and their mentor Jorge, who gave us a tour to the different excavation site. We started at the Centenario Bridge then move to the Las Cascadas Formation. At the Las Cascadas Formation I followed Nathan and Chris towards the fossilized leaf deposits while the others stayed at the bottom layers looking for vertebrate remains. At the leaf site the outcrop was divided in a top layer of oxidized sediments and a bottom grayish layer. Nathan tells us that that last time he visited the site he had found fossilized leaves in the oxidized layers.  So I sit and commence to excavate with him, but the outcrop crumbles in my hands and I don’t seem to find anything. After a while I decide to excavate in the grayish layer just for curiosity, so I grab my hammer, hit the outcrop with all my strength and take out a big block, when I flip it I discovered the most beautifully preserved leaf. In my excitement I show it to Nathan and he practically starts jumping with joy on one leg!  We then visited the Empire site looking for some crabs. AtOLYMPUS DIGITAL CAMERA this locality we had to be aware of our surrounding because it was being worked with bulldozers extracting sediments. It made it difficult for us to extract fossils with all the dust in the air that would get stuck in our eyes, but that still didn’t stop us for making great findings. We ended the day at Hodges Hill collecting fossilized wood.

Tuesday, March 3

Chris, Nathan, Roger, Will, Cristina, and I went back to the Las Cascadas Formation to the leaf site. Roger, Will and Cristina were looking for arthropods; Nathan, Chris and I were looking for botanical fossilized remains, and we spent most of the day there digging a quarry.

Wednesday, March 4

For the first half of the day I was with Nathan and Chris collecting fossilized wood in Hodges Hill. We found a large trunk and some crabs. In the afternoon Victor and I were sent to the Las Cascadas Formation to dig up some vertebrate fossils while Roger, Nathan, Chris, Cristina and Jorge went to the east side of the canal to explore the new sites containing fossilized crabs and leaves. Once I was in the Las Cascadas Formation all I could find was fossilized roots, so every time I would call John  to check what I had found he would say it was a root. After I had gotten tired of the spot I was given to excavate I decided to move towards the shale. At first all I could find was matrix when suddenly I come across something shiny, I called out for Jon saying “Jon I found something!!” He tells me “What is it?” I respond “I don’t know”. Jon sends Aldo to check what I haOLYMPUS DIGITAL CAMERAd, after a while of Aldo looking at it Jon asks “Well, what is it?” Aldo responds “I think you might need to look at this” Jon practically came running towards us to see what we had. To make a long story short there are three possibilities of what my findings are. Jon and Aldo strongly believe it might be a horse tooth but we won’t know for sure until the whole tooth has been cleared from the surrounding matrix…. I knew I had found something.

Thursday, March 5

This time I went with the group from the day before to the east side of the canal. After the previous day of exploring the site Nathan had an idea of where the fossilized leaves and fruits might be, so Nathan, Chris, Jorge, Sonia and I started exploring the jungle of elephant grass, it was so high and thick that we could barely move through it. We had to use our hammer or throw ourselves in the grass to lower it down and make a path; we couldn’t use a machete becauseOLYMPUS DIGITAL CAMERA we had left it at the west side of the canal so we had to manage with what we had… made me feel like if we were in an episode of Man vs. Wild! After walking through the grass we finally found the site.

Friday, March 6

Cristina, Sophie, Nathan, Chris and I tried to enter the east side of the canal again but our permit had expired so we had to return to the west side of the canal. We notified the others of our group and made an exchange of people, Chris for Jeremy. So Jeremy, Nathan, Cristina and I went to Empire site to find some fruits, we spend half of the day there and found plenty of seeds. During the late afternoon we visited the Biomuseo.

Saturday, March 7

We renewed our permits and spent the day at the east side of the canal digging a quarry for the new leaf site and collecting good samples. At the end of the day Nathan, Justy and I went to Casco Viejo and explored Panama City. We had a great time on our last day in Panama.

Visiting Panama has been an extraordinary experience filled with new adventur10988434_857802634281131_7377436034996016052_oes, experience and culture. Plus, now that we have collected so many fossilized leaves I can try to identify them and compare them to the ones of Tennessee. Also, we can make a booklet of the collected leaves for when we return to Panama so that we can find them again in the field and can easily know which leaf was discovered.

Until next time!

Spring Break in Panama

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Photo of the Spring Break Panama Canal participants at the Canopy Crane.

This week 15 additional people descended on the Panama Canal – the University of Florida Spring Break crew has arrived. For the majority of participants, this is their first experience in Panama.  We arrived Saturday afternoon and took Sunday as a tourist day to see the sights – the canopy crane and Punta Culebra were both great activities.

The first group is hooked up to the crane, which lifts them into the tree canopy.

The first group is hooked up to the crane, which lifts them into the tree canopy.

The view from the crane.

The view from the crane.

This iguana was sunbathing in the treetops.

This iguana was sunbathing in the treetops.

Punta Culebra

Vista at Punta Culebra.

Monday morning brought us to the Panama Canal.  We depart our hotel at 7AM, get to the canal around 8:30, and work until 3:30.  Quite a few fossils have been found – lots of new vertebrate, invertebrate, and paleobotanical samples are filling the lab at STRI!

AndreaVictorRachel Emperador

Andrea De Renzis, Victor Perez, and Rachel Narducci search the Empirador Formation for sharks teeth and invertebrate marine fossils.

Dawn Mitchell searches for vertebrate fossils in the Las Cascadas Formation.

Dawn Mitchell searches for vertebrate fossils in the Las Cascadas Formation.

Museum Intern Will Tifft takes a swing at a difficult layer of Las Palmas along the Panama Canal.

Museum Intern Will Tifft takes a swing at a difficult layer of Las Palmas along the Panama Canal.

Fossil Friday 1/16/15: A fossil camel

VP 236939 occlusal

An occlusal view (showing the biting/grinding surface of the teeth) of UF 236939, a partial dentary of Aguascalientia panamaensis. From this view, you can see that this dentary includes the left and right canines (c1), the right premolars (p1-3), and the right molars (m1-3). The lowercase letters denote that these teeth are lower teeth while the numbers describe the position in the mouth. (Photo © VP FLMNH)

This Fossil Friday I would like to introduce you to a floridatraguline camel from the early Miocene Las Cascadas Formation of the Panama Canal Area, Aguascalientia panamaensis. An interesting fact about this fossil is that both the first premolar and first canine are caniniform, a feature shared among the camels of the genus Aguascalientia. Floridatraguline camels (subfamily Floridatragulinae) are an extinct subfamily of llama-like camels characterized by elongated snouts and relatively primitive dentitions. In the early Miocene their distribution in the rest of North America was restricted to subtropical areas such as Florida, Mexico, and Texas.

To find out more about this specimen and other floridatraguline camels, read the publication describing them here.

Preparing a Fossil Dugong from the Panama Canal

Fossil prep tools

Preparing a fossil requires a variety of tools, some of which are shown here. Top left to bottom right: spray water bottle, lubricating oil for airscribes, acetone, PVA, carbide picks, brushes, a PaleoAro and a microjack (airscribes of different sizes and strengths), dust mask, goggles, and ear muffs for noise protection.

The first project I got started on at FLMNH was preparing a fossil dugong from the Culebra formation of the Panama Canal. My main focus has been on a cluster of vertebrae that are held together by a carbonate and siltstone matrix. The process of preparing this fossil is rather slow going because the matrix is extremely hard and nearly the same color as the bone. To help distinguish them, the fossil is sprayed or brushed with water to remove dust and help bring out the color of the bone. While it is damp, I use carbide picks and airscribes (basically handheld jackhammers) to remove the matrix. The goal at this step of preparation is to remove as much matrix as possible while leaving a thin layer just above the bone and to leave any areas where it is too difficult to distinguish between bone and matrix. Next, a thin layer of PVA, a glue reversible with acetone, is added to protect the bone when it is placed in a diluted formic acid bath. The acid breaks down some matrix but does not damage the bone, although some etching can occur over time. The fossil is then soaked in running water to remove any remaining acid and the PVA is removed to begin the process of manually removing matrix over again. Broken pieces of bone often become loose after the bath and must be secured with glue before continuing.

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The fossil lab station where Dawn prepares the dugong vertebrae. She uses a surgical microscope that can easily pivot to get multiple views of the fossil while she uses tools to remove matrix.

Preparing this fossil has taken a lot of time and the effort of many people, and it still requires much more before it is finished. But progress is being made; when I started I couldn’t see through the neural canal of one vertebra, but now I can! Once preparation is completed, this fossil promises to provide us with interesting new information on Miocene dugongs from the Panama Canal area.

To learn more about the dugong fossil, check out this article written by former PCP-PIRE intern Sarah Widlansky: http://www.flmnh.ufl.edu/panama-pire/archived-enews/2014/v4i1r/.

Wesley von Dassow at GSA

Summer 2014 PCP PIRE intern Wes von Dassow presents this morning on the field course in the Azuero Peninsula in Panama. He is viewing it from the vantage point of international collaboration, as the bilingual geological field camp was run by Universidad de Los Andes in Colombia and attended by Colombians, Panamanians, and Americans. Former interns Michelle Barboza and Robyn Henderek (who presented on Sunday) were also in attendance.

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