DOSECC Projects

• Continental Margins ( 3 Articles )
• Current and Future Drilling Projects ( 6 Articles )
  

  DOSECC Projects Map 

• Lake Drilling ( 10 Articles )
  Lakes are dynamic response systems that record the complex interaction between land and aquatic environments and their respective ecosystems. Lake sediments are among the best continental archives to establish time series changes in lithology, sedimentology, geomagnetism, terrestrial and aquatic paleoecology, carbon-cycle elements, and geochemical and isotopic signatures. By establishing coherent regional paleoclimate patterns, data can be compared across continental climate zone transects and on global scales to test global earth system modeling and hypotheses of climate change.

  Lake sediments offer certain tangible advantages over other climate archives; both modern and ancient lake deposits are widely distributed and accessible over the continents. Sedimentation rates of these archives are typically high and continuous, and the sediments contain a variety of signals sensitive to geosphere, hydrosphere and biosphere components. Because lakes also exhibit individual complexities, it is important to reconstruct paleoclimate records from a network of sediment cores in order to understand how each unique lake system is responding to regional and global forcing.

  DOSECC has three drilling systems in operation that are designed to accomplish a variety of projects in lakes and shallow marine environments. DOSECC designed and built the GLAD800 and GLAD200 lake coring systems and completed several coring projects (see links above).

  The projects have been completed with high core recovery rates and have fostered studies of climate history, seismic hazards and environmental assessment. In addition, DOSECC designed and built an active heave compensated drilling rig (AHC800) that can be used in large lake and shallow marine settings. In addition, we have Dynamic Positioning capabilities that can be used on platform barges or ships where it is necessary to maintain position "over-hole" during coring operations.

• Meteor Impacts ( 5 Articles )
• Volcano Monitoring ( 8 Articles )
  Subsurface monitoring of tectonic processes and the prediction of volcanic eruptions has obvious societal as well as scientific importance. DOSECC installed instrument packages containing borehole strain meters and three-component seismometers at three sites around Mauna Loa volcano on the Island of Hawaii and on the island of Montserrat.

  Current technology for borehole strainmeters and tiltmeters can detect strain and tilt changes of less than 1 part per billion over periods from milliseconds to months allowing for both detection of volcanic events at great distances and a temporally complete record of volcano deformation. These instruments provide substantially better data than continuous GPS systems which have relatively poor resolution (at best ~3mm horizontal, ~10mm vertical), are contaminated by long period noise (e.g., 20-minute period multipath noise), and present data reduction complexities that make real-time analysis of the results difficult and unreliable.

  Borehole seismometers likewise obtain improved data resolution by avoiding surface noise. Observations of Long Period events in the Long Valley Caldera suggest that similar events related to magma movement in Hawaii may be recorded by a borehole seismometer, located at a depth of several hundred meters, with noise levels 1000 times below surface values. Observation of these events for volcano monitoring is a critical element in the Volcano Hazards Program priorities.

• Other Projects and Programs ( 12 Articles )