sed_comp

 PI:              Bob Anderson
 of:              Lamont-Doherty Earth Observatory
 dataset:         Sediment composition
 project/cruise:  AESOPS/NBP96-4
 ship:            R/V Nathaniel B. Palmer

 Notes:  CaCO3 measured by coulometry.
         Opal measured by alkaline leach and spectrophotometry.
	 The concentrations reported are for biogenic opal, 
	 which includes 11% by weight water (SiO2*0.4H2O).

 Reference:  Mortlock R.A., Froelich P.N., 1989. A simple method 
             for the rapid determination of biogenic opal in pelagic 
	     marine sediments. Deep-Sea Research 36, 1415-1426.


 Parameter      Description                                   Units

 event          event number from event log
 sta            station number from event log
 lat            latitude, minus value means South             decimal degrees
 lon            longitude, minus value means West             decimal degrees
 core_type      type of coring instrument used,
                  where GC = gravity core
                  where MC = multi core
 depth_w        water depth                                   meters
 depth_core     depth in core, mid-point of interval          centimeters
                  sampled
 depth_core_sd  depth in core, standard deviation             centimeters
 CaCO3          calcium carbonate, weight percent             percent
 Si_opal        opal, weight percent                          percent
 Si_opal_dup    opal, duplicate analysis, weight percent      percent