Day 11 (Thursday 16 September)   Datalogging is a long and fancy word for collecting data long term via computer.  Holes are drilled into the sea floor to either to collect a sediment core or place an ACORK inside and this is the perfect place to gather data from equipment that are mounted on long spear like structures.  The sensors collect data on characteristics such as density, porosity, temperature, resistivity, magnetism, radioactivity, and more.  There is also a sonic tool that makes a map of the particular spot using reflected sound.  Datalogging is helpful because cores sometimes have missing sections and bringing them to the surface causes the sediments to expand a bit due to pressure changes.  Datalogging is also helpful to match up the cores layers from one hole to another.   The Datalogger specialist is an engineer that gets to ‘play’ with some very expensive ‘toys’!   One difference between the JOIDES and an oil drillship/platform is that we don’t have a dedicated pipe to put the sensors downward so you can not be drilling and datalogging at the same time.  I bet that one day in the future we will all be gathering ocean floor sensor data on our iphones!