I'll start a new thread because the previous one is pretty old. Did not get a chance to post much on the data acquisition cruise off of Istanbul. I'll try a couple here, or maybe just this one.
We were collecting seismic reflection data across the North Anatolian fault system in Marmara Sea, offshore Istanbul. This method uses sound to reflect off the seafloor and also subsurface layers. The sound also reflects off the sea surface so you get "multiple" reflections. To see deeper than twice the two-way travel time of the sea floor, you need multichannel data, and then you process these data to attenuate the multiples. For marine multichannel data, you tow a streamer with groups of hydrophones.

The system on the Piri Reis is high-resolution. We used a small sound source, and towed a 600 m-long streamer, with up to a 100 m-long lead in cable. The problem for us/the captains is that one of the busiest shipping lanes in the world runs through Marmara Sea between the Dardenelles and the Bosphorus. While we were there, a tanker lost its rudder and ran into Istanbul while attempting to run through the Bosphorus. It damaged a park and building,bounced off and ran aground on the other side. You probably did not hear about it because as far as I know it did not leak oil etc.

So, the captains were really reluctant to cross the shipping lanes at first. It took a couple of days for them to get used to the traffic patterns...we crossed the shipping lanes with the streamer behind first about 100 km west of Istanbul. The Bosphorus is one way: 12 hours one way, 12 hours the other way. Many dozens of ships park in various parts of eastern Marmara Sea waiting for the Bosphorus to open. This is in addition to the 75 ships parked in front of Istanbul (where we also anchored). Finally, we were able to get data across the shipping lanes not too far west of Istanbul (Kumbergaz (sp?) Basin). We also acquired data southeast of Istanbul...but not crossing the Bosphorus-bound main shipping lanes (instead, crossing traffic headed towards Izmit bay/city, including high-speed ferries). We only collected data there during the day, before evening rush hour (we would head off towards the west/southwest to collect data afterwards)

While we were acquiring data 50 or so km west of Istanbul (maybe more), the largest annual yacht race in Turkey started. We/the captains were aware of this, and were collecting the last N-S line, headed south. We collect data at about 5 knots (9 km/hr). There was a good wind so the sailboats were going (much) faster. I was taking a break up top watching one of the lead boats, the most southern one...and it passed not all that far behind our tail buoy (end of streamer).

The French collected deep crustal seismic reflection data in eastern Marmara Sea a few years ago towing a 4.5 km-long streamer. But, it was their streamer, it wa stowed much deeper, they probably had Turkish Navy escort boat (?), and apparently there was a little less traffic then.

Anyhow, the equipment all survived our cruise.
Maybe some science later.
Chris