Feeling Like A Scientist

The truth is, most of my time researching science is spent in front of a computer either programming in MATLAB, making figures in Illustrator, or writing in Word.  Another large chunk of my time is spent out in the field collecting samples and recording data like water temperature.  A surprising small amount of my time is spent in the lab analyzing samples.  Even less of my time is spent conducting experiments actually in the lab.  This research project is the exception.  For this project I have to actually work in a lab conducting very controlled experiments.

A schematic of how the residence time (length of time) of seawater in marine sediment can vary with distance from the shore.  In this example seawater further away from the ocean in the sediment of the beach has a longer residence time than seawater in the beach closer to shore.

As can be read on the student's page (link above) the goal of my research project is to quantify how long seawater has been in marine sediment, something we call the residence time of seawater in marine sediment (more commonly known as the beach).  We care about how long seawater has been in marine sediment because the longer seawater is in marine sediment the more time it has to change composition (like becoming enriched in pollution) before it circulates back to the ocean (now enriched in whatever was in the sediment).

In Eilat, I am trying to simulate this in the lab with a column experiment.  In the experiment, I pass seawater through a column of local marine sediment at a known flow rate (using a peristaltic pump) and therein known residence time.  I then filter the water to collect the water constituents I care about measuring (in this case the element radium).  I also measure how much water passed through the filter so that I calculate a concentration of radium in the seawater after it passed through the column of sediment.   I run these experiments for several hours periodically checking the flow rate with a graduated cylinder and timer.  At the end of the experiment I run the filter on an instrument for radium concentration.

Hopefully by the end of summer I will know how the residence time of seawater in the column affects the radium concentration.