Impact Effects: Chicxulub
Please note: the results below are estimates based on current (limited) understanding of the impact process and come with large uncertainties.
Note that the estimated environmental consequences of the Chicxulub impact have been projected onto the present-day Earth. They therefore show the approximate consequences of a Chicxulub-scale impact if it happened today. The position of the major landmasses 65 million years ago was somewhat different than it is today. Reconstructions of the continents at that time are available here
Estimated Chicxulub Parameters:
- Projectile diameter: 12.00 km ( = 7.45 miles )
- Projectile Density: 3000 kg/m3
- Impact Velocity: 20.00 km per second ( = 12.40 miles per second )
- Impact Angle: 90 degrees
- Target Density: 2700 kg/m3
- Target Type: Liquid water of depth 500.0 meters ( = 1640.0 feet ), over crystalline rock.
- Energy before atmospheric entry: 5.43 x 1023 Joules = 1.30 x 108 MegaTons TNT
- The average interval between impacts of this size somewhere on Earth during the last 4 billion years is 1.0 x 108years
Major Global Changes:
- The Earth is not strongly disturbed by the impact and loses negligible mass.
- The impact does not make a noticeable change in the Earth's rotation period or the tilt of its axis.
- The impact does not shift the Earth's orbit noticeably.
- What does this mean?
- The crater opened in the water has a diameter of 141 km ( = 87.7 miles ).
- For the crater formed in the seafloor:
- Transient Crater Diameter:
85.7 km ( = 53.2 miles )
- Transient Crater Depth: 30.3 km ( = 18.8 miles )
- Final Crater Diameter:
154 km ( = 95.4 miles )
- Final Crater Depth: 1.35 km ( = 0.836 miles )
- The crater formed is a complex crater.
- The volume of the target melted or vaporized is 4660 km3 = 1120 miles3
- Roughly half the melt remains in the crater, where its average thickness is 808 meters ( = 2650 feet ).
Tell me more...
Click here for a pdf document that details the observations, assumptions, and equations upon which this program is based. It
describes our approach to quantifying the important impact processes that might affect the people, buildings, and landscape in the
vicinity of an impact event and discusses the uncertainty in our predictions. The processes included are: atmospheric entry, impact
crater formation, fireball expansion and thermal radiation, ejecta deposition, seismic shaking, and the propagation of the atmospheric
Earth Impact Effects Program Copyright 2010, G.S. Collins, Robert Marcus, and H.J. Melosh.
These results come with ABSOLUTELY NO WARRANTY