Under the auspices of the International Continental Drilling Program, the first effort to obtain a continuous core of rock from the deeply buried Chicxulub impact crater was initiated in December 2001. Known as the Chicxulub Scientific Drilling Project, the goal is to drill through the 500 to 1000 meter thick sequence of sedimentary rocks that cover the crater to obtain samples of impact breccias and impact melt created within the approximately 180 km diameter crater. Professor Kring at the University of Arizona (UA) is on the project's Science Team and a co-investigator of the project. In February, Kring and one of his UA undergraduate students, Jake Bailey, worked at the drilling site with their colleagues from Mexico's universities.
|The drilling site is called Yaxcopoil-1, because it is located near the Yaxcopoil hacienda in the Yucatan, Mexico. This view was taken on a cool clear morning. Often conditions are hot and steamy or wet with rain. Photograph by David A. Kring, NASA/UA Space Imagery Center.|
|The Drilling Team is composed of people from DOSECC (Drilling, Observation, and Sampling of the Earth's Continental Crust, Inc.), which was initiated by the NSF and the University of Hawaii, and Pitsa, a drilling contractor in Mexico. In this view they are working on a core sample that they pulled up from a depth of about 1,270 meters (roughly 4,200 feet). They will then hand the core barrel to the geology team from the University of Arizona who will extract it and begin processing the sample. Photograph by David A. Kring, NASA/UA Space Imagery Center.|
|University of Arizona undergraduate student Jake Bailey is washing a rock core sample that the geology team received from the drilling team. Each section of rock core that is recovered from the borehole is about 3 meters (10 feet) long. While the sample is being washed, it is supported in a long white tray. As the sample is being washed, the geology team makes an initial assessment of the core. They determine the type of rock that was recovered, measure it, examine it for faults and other features that can be used to interpret the structure of the deeply buried crater. Photograph by David A. Kring, NASA/UA Space Imagery Center.|
|University of Arizona's Professor Kring holding a long segment of rock core that was recovered from about 4,200 feet. This core is composed of several layers of sedimentary rock that either represent a mammoth block of rock in the crater's impact breccias or the fractured floor beneath the crater. It is a sample of the rocks that were hit by the asteroid or comet that produced the vast Chicxulub crater. It is composed mostly of anhydrite (a calcium sulphate mineral) which, when vaporized in an impact event, produces sulfur-oxide gases that can alter Earth's climate. When injected into the atmosphere by the impact event, the sulfur-oxide gases form aerosols which cooled the Earth's surface and then eventually rained out of the atmosphere as sulfuric acid rain. This was probably one of the more severe consequences of the impact event and is likely partly responsible for the extinction of dinosaurs and other species 65 million years ago. Photograph by Jake Bailey, NASA/UA Space Imagery Center.|
|A pile of metal core barrels that will be added one at a time as the drilling project reaches greater depths. While the UA team was at the drilling site, one of these 3 meter (10 feet) long segments was added to the drilling stem every 2 to 2.5 hours. The DOSECC and Pitsa drilling team was doing a fantastic job, recovering 35 to 40 meters each day. This exceeds the goal of 25 to 30 meters/day and is helping produce an exceptional core sample. Photograph by David A. Kring, NASA/UA Space Imagery Center.|
|Operations at the drilling site occur 24 hrs/day, 7 days a week, including holidays. This is a view of the top of the drilling rig when the University of Arizona team was working one of the nighttime shifts. The cylinder in the center of the rig is designed to apply pressure to the diamond drill bit to help it penetrate deeper into the Earth's crust. Photograph by David A. Kring, NASA/UA Space Imagery Center.|
|Lights are needed for the drilling team and for the geology team to continue operations during the night. In this view the air is clear, but ground fog often rolls through the Yucatan forest at night, adding an eery glow to the scene. Photograph by David A. Kring, NASA/UA Space Imagery Center.|
|The drilling team is working on the drilling platform to recover another segment of rock core during night operations. The computers that help the drilling team control the drilling are located in the white operations shack in the left portion of the image. Photograph by David A. Kring, NASA/UA Space Imagery Center.|
|The wellhead on the drilling platform, illuminated by lights during night operations. The drilling stem is the vertical cylindrical barrel in the center of the image. The diamond drill bit is thousands of feet below the drilling platform. The weight of the metal drillstem is so great, that the metal pipes stretch in deep boreholes like this one. Photograph by David A. Kring, NASA/UA Space Imagery Center.|
|Dr. Mario Rebolledo, a principal figure with the geology team from the Universidad Nacional Autonoma de Mexico (UNAM), with University of Arizona undergraduate student Jake Bailey. They are working on a core sample recovered during night operations. Photograph by David A. Kring, NASA/UA Space Imagery Center.|
|This is the rock core that contains the contact between the sedimentary rocks that bury the crater and the top of the rocks in the Chicxulub impact crater. The rocks that bury the crater are the light-colored (approximately white) rocks in the top left portion of the image. The first of the impact breccias recovered in the crater are the green rocks in the top right and bottom half of the image. This image was taken at the core processing laboratory at the University of Yucatan in Merida, where the rock core is transported from the Yaxcopoil-1 drilling site each day. Photograph by David A. Kring, NASA/UA Space Imagery Center.|
Graphic representation of the Chicxulub impact structure (For Download):
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A schematic diagram of a buried complex crater with
impact breccias overlying impact melt.
This is a generalized diagram of how the Chicxulub impact crater may be structured. It is buried beneath several hundred to one thousand meters of sediment, so drilling is needed to sample rocks from the impact crater. The Chicxulub Scientific Drilling Project is designed to drill through the overlying sediments, the impact breccias, the impact melt, and into the underlying impact-fractured rock.