Updates from expedition to probe the world's deepest sinkhole

Jackson School of Geosciences writer Marc Airhart joined an expedition to a series of water-filled sinkholes, including the world’s deepest - El Zacatón - in March and May 2007. Read his Dispatches from Zacatón as they first appeared in the Houston Chronicle’s SciGuy blog:

Part 1: March 8-14, 2007

Preparing for a journey into the unknown (March 08, 2007)
I'm heading to Mexico this morning to help document an amazing research project at the world's deepest known water-filled sinkhole, or cenote. The research will help scientists determine the physical and chemical processes that have formed a unique and immense cave system, better understand how microbes live in extreme environments and develop technology that might someday aid the search for life beyond Earth. Continue …

Clock is ticking for DEPTHX team (March 10, 2007)
I awoke on my first morning in Mexico to a rooster crowing, followed by song birds lilting and finally a burro baying in the little village across the river. The scientists and engineers, about a dozen from Texas, Pennsylvania and Colorado, ate some cereal, downed some coffee and headed off to work. It took years of preparation to get to this point in the mission. Now that the robot and the scientists are all here and the last few months of funding are left, time is in short supply.
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The Goat Head Theater (March 11, 2007)
Hello from Sistema Zacatón. Saturday, day two of the current mission, the scientists and engineers here made enough progress in solving a series of engineering problems and some mysterious new glitches that they were actually able to start doing a little science. Continue …

Hands-on science (March 12, 2007)
Today I got to do a little hands on science. It must have been some momentary lapse of reason. Or maybe boredom had set in. But they agreed to let me maneuver the robot for a couple of minutes. They handed me the joystick, which I was delighted to learn is a Nintendo video game controller. Engineers don't like reinventing something that already works. Continue …

Oh my darling -- vehicle lost! (March 14, 2007)
I'm now back home in Austin, Texas nursing a few nasty chigger bites (in the end, it's the chiggers that gave me the most trouble, not the ticks) and marveling at the amazing experiences I had in Mexico observing the DEPTHX mission. For my final entry, I have to mention the events of Sunday night and Monday morning, March 11 and 12. Continue …

Postscript (March 14, 2007)
The DEPTHX team is now wrapping up this month’s mission. Monday evening (March 12th), they successfully landed on the bottom of La Pilita at over 100 meters deep, collected core samples from the rock wall using the sample arm and sampled sediments at the bottom using two “pooper scoopers” (really just inexpensive metal dust pans attached to the underside of the robot). The team gave DEPTHX a challenge Tuesday afternoon (March 13th): they wiped the robot’s memory so that it was as if it had never been in La Pilita before and forced it to make its own map and maneuver its way around the cenote from scratch. It worked! They still need to make some improvements, but the team is very optimistic about their ability to be successful when they return in May to release DEPTHX into Zacatón.

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Read Marc's further adventures at Geology.com:

Part 2: May 14-22, 2007

Pre Trip Report (May 11, 2007)
I am returning to Mexico on Wednesday, May 16. This time around, DEPTHX will dive three times deeper than it has ever gone before to explore the depths of Zacatón, where no human has ventured. What might it find? New forms of life? Hydrothermal vents like those in Yellowstone or deep on the sea floor? Side caves that connect Zacatón to other caves and sinkholes? Lost Aztec gold? Continue …

The Bottom of Zacatón (May 17, 2007)
When I arrived at Rancho La Azufrosa last night (Wednesday), the DEPTHX team was wrapping up a very successful day. The robot had just made the first ever map of the bottom of El Zacatón using its sonar sensors. Finally, a picture of the mysterious depths that eluded two divers 13 years ago was coming into focus. Continue …

Not all caves are created equal (May 18, 2007)
We took a field trip to Caverna Cuarteles, a large dry cave a short walk from the ranch. Bats flitted above our heads and spider-like insects hid from the beams of our headlamps as we moved from room to room admiring the rocky daggers, veins and curtains decorating the ceiling. Here and there, massive tree roots thrust down through the rock seeking water. Continue …

Put a Lid On It (May 19, 2007)
There's a sequel to the geologic story of how these sinkholes formed. Some appear to be in the process of closing up at the top as crusts of travertine (a form of calcium carbonate) form at their surfaces. It's a bit like the skin on a can of paint that has been left open in the sun. For the paint, it might take a day or two. In this case, the process probably takes thousands of years. Continue …

The Hits Just Keep on Coming (May 22, 2007)
Now that I’ve returned home to Austin, it’s amazing to think how much the team has already accomplished. By any measure, it’s been a smashing success.
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At Last, Back in the Water (June 20, 2007)
I had the good pleasure of sitting down with Marcus Gary, a doctoral candidate at the University of Texas of Austin and one of the primary members of the DepthX team, to talk about what happened after I left Mexico on Monday, May 21. After several days out of commission, the DepthX crew was finally able to return to work on Friday, May 25.
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Marcus Gary a scientist from the University of Texas at Austin wrote his own online record of this DEPTHX mission. Check out his excellent daily updates:

• Marcus Gary's page for the DEPTHX-Zacatón expedition.

For more information about the Jackson School, contact J.B. Bird at jbird@jsg.utexas.edu, 512-232-9623.