The picture is consistant with a "Water Jet" type pile driver. The house at the stern would probably contain a large slow turning Gas or Diesel engine that could be used for two purposes: One as a propulsion engine if the barge is self propelled. (unlikely I think) Secondly, the engine would drive a water pump.
The "A" frame derrick at the bow......and it
may be a
Tripod with one of the legs hidden behind the left leg in the picture. The "other" slimmer thing hanging from the top of the derrick would be the water jet pipe (like a soda straw) with a hose running off the top of the pipe and sagging back off to the engine/pump house.
The piling would be hung off the top of the derrick with the water jet pipe hugging the side of the piling with the bottom end of the pipe near the bottom of the pile. Water is pumped down alongside the pile through the pipe at high pressure... dislodging the bottom material up and out of the "water drilled" hole ..allowing the pile to sink into the bottom. When the pile settles to the desired depth under its own weight, the jet pipe is withdrawn and the pump is turned off... allowing the walls of the hole around the pile to collapse around the pile and the work is done.
The front face of the wheelhouse seems to be at a different ..odd angle to what "appears" to the face of the derrick, ...which leads me to believe the what looks like an "A" frame is actually a tripod with the center/back leg (with ladder steps) ..on the centerline of the barge.
The picture is a little dark but I think there is a "donkey engine" ...or winch in front of the wheelhouse.
Last but not least: The barge seems to be grossly "Hogged" and will probably
open it's seams and sink, not long after the picture was taken.
NB