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| Daily Report from Anthony Johnson
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| A bright new day, knowing that we are going to sail. The Langseth left the waterfront at 1050 PDT (1750Z); local traffic on the Columbia delayed removal of the last line. We sail out on a beautifully sunny day, many small craft fishing for salmon; harbor is calm, winds at 10 Kts. The run out the Columbia takes a couple of hours. After crossing the Columbia bar at ~1300 PDT we begin transit to the survey area. ETA at the first drop site is ~0900 PDT on August 23.
PIs meet with Anthony and David to discuss shooting parameters for the seismic survey. The MGL shoots on distance, preferably. That distance depends on ship’s speed and rep rate of the guns. For the undershoot lines we will want to achieve a shot offset time of ~210 s. At 4 Kts, that will be about 420 m.
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| Watches are started, schedule:
WatchSchedule.pdf
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| Various terms are used to describe the shooting:
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| Line name: ordered geographically per the experiment plan.
Sequence number: Increments sequentially with the beginning of each new line.
MGL0910_XX_{R1,R2,...} is the format of our line names. XX is the line name, the R1 and R2 are for reshoots.
Shot numbers will be unique throughout the experiment. For each sequence number, the first shot on the grid will be #021, where # is the sequence number; this is discussed in more detail in the appendices.
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