Gravity coring device after sampling Yellowstone Lake sediment

Gravity coring device on the rear deck of the R/V Annie after coring the floor of Yellowstone Lake, with dark mud coating the outside of the corer.  The 100-lb. green coring head is at the top, and the bottom of the barrel has a tapered stainless steel core cutter.  Mud-filled plastic core-liners are removed from the core barrel and replaced with a new core liner for the next core.  Thermal outriggers are the two fin-like appendages on the core barrel that hold recording thermistors for heat flow measurements.