1 week 6 days
Expedition 344: Costa Rica Seismogenesis Project
Costa Rica Siesmogenesis Project A, Stage 2 (CRISP-A2)
23 October to 11 December 2012
Days at sea: 3 transit + 44 operation days
Panama City, Panama to Puntarenas, Costa Rica
Co-Chief Scientist: Robert Harris (College of Earth, Oceanic, and Atmospheric Sciences, Oregon State University, USA)
Co-Chief Scientist: Arito Sakaguchi (Institute for Research on Earth Evolution, JAMSTEC, Japan)
Expedition Project Manager/Staff Scientist: Katerina Petronotis (IODP-USIO, Texas A&M Univeristy, USA)
Logging Staff Scientist: Alberto Malinverno (Lamont-Doherty of Columbia University, USA)
Education Officer: Dena Rosenberger (El Capitan High School, USA)
Have you ever felt an earthquake? The magnitude 9.0 earthquake in Japan in March of last year brought earthquakes into the news in a big way! Costa Rica just had a magnitude 7.6 earthquake in September of this year. These two events happened along a plate boundary where one plate is pushed under another plate, called a subduction zone. Join Expedition 344 scientists as they try to understand how earthquakes form (seismogenesis) where plate boundaries exist, specifically in subduction zones.
During the 47-day expedition, the JR scientists will try to understand how and when the Cocos plate (in the Pacific Ocean) started pushing under the Caribbean Plate, which holds Guatemala, Honduras, El Salvador, Nicaragua, Costa Rica, and Panama. These countries make a land bridge that connects North America and South America (see map). The CRISP (Costa Rica Seismogenesis Project) Expedition will try to find out what is happening with these plates as they push under each other along the area called the Costa Rica Subduction Zone. This expedition will continue where the first CRISP Expedition (Expedition 334, from March 13 to April 13, 2011) left off.
Specifically, the upcoming expedition (CRISP 2) will:
1. Recover good quality sediment cores on the incoming plate (the Cocos plate)
2. Drill at the frontal prism sediments and decollement (see diagram below)
From: Long-term hydrogeochemical records
in the oceanic basement and forearc prism at
the Costa Rica subduction zone.
Diagram courtesy of M. Kastner (SIO)
Specifically, the scientific objectives are:
1. Determine when the Cocos Plate started being pushed under the Carribean Plate and how that might have affected earthquake formation.
2. Determine when the volcanos and mountains in Central America formed.
3. Determine when some of the volcanos in Central America stopped erupting.
This expedition will focus on sampling the rocks and fluids at the subduction zone, and measuring the temperature and stresses that might cause the plates to slip and cause an earthquake.
About 5 million years ago, the subduction of the Cocos Plate under the Caribbean Plate caused the volcanic land bridge to start forming between North America and South America. Sixty-eight volcanoes, many still active, are included in this chain. When this land bridge formed, the climate of the entire planet was affected. The Atlantic Ocean and the Pacific Ocean were no longer connected, and the Gulf Stream started flowing north along the eastern side of North America. Animals and plants were now able to travel between the two continents, as well, introducing new species to both.
For a wonderful explanation of plate tectonics, watch National Geographic's "Colliding Continents"
To read the full scientific prospectus, go to: