Here is a copy of a letter I wrote that was published in Dive Magazine in the UK. I thought I'd post it here to see if anyone had similar experiences.
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On a recent diving holiday in Egypt I shared a taxi with a stranger going to Dahab. After some chatting I found out that they worked as a Marine Mammal Observer(MMO) for an organisation in the UK. Intrigued, I asked them more about their job.
It transpired that they worked on a contract basis for oil companies who do seismic surveys and exploration. Seismic survey work involves detonating explosive charges above the surface of the water approximately every 10 seconds. The resulting noise level for each is over 200Db. The shockwaves are monitored as they rebound, to build up a picture of the ocean floor.
The MMO's job is to survey the ocean surface during these surveys and call a halt to the operations if a marine mammal is seen within 500m of the vessel. Can this be seen as anything more than a token gesture?
In June 2007, on a trip to the Philippines, I personally experienced the underwater effects of a seismic survey. I was diving off Bohol when a survey operation took place 25 - 35 km to the north near Cabilao. I was stunned at severity. I first thought that someone was dynamite fishing nearby, but the perfect regularity of the shockwaves soon left me in no doubt about what was taking place. The underwater effects were enough to leave me with a severe headache for several hours after my dive. What would it have done to me if I were only 500m away! This has to stop!
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The following is another account of the same seismic survey from a local Filippino fisherman.
'At the hearing on June 27, a Cabilao fisherman gave his testimony that the previous week he had gone spearfishing while the seismic survey was conducted in the seas off Sibonga, Cebu, more than ten kilometers away, and that upon diving he heard the underwater explosions, which at a depth of three fathoms were distinct and at which he began to feel vibrations in his abdomen and upper torso. At a depth of five fathoms the explosions were louder and the vibrations of his abdomen and upper torso grew stronger and at that moment he decided to surface. Since that incident he only went spearfishing on the other side of Cabilao Island, away from where the explosions came.'
extract from : Seismic Survey Chronicles (Part I) | PROCESS-Bohol, Inc. Official Website
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I was limited to 250 words in my letter due to magazine restrictions. I can confirm though the feeling described in the other article. I felt my insides vibrate. I could literally feel the shockwaves pass through my internal organs. It is like nothing else I have ever experienced as well as extremely unpleasant and disconcerting.
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On a recent diving holiday in Egypt I shared a taxi with a stranger going to Dahab. After some chatting I found out that they worked as a Marine Mammal Observer(MMO) for an organisation in the UK. Intrigued, I asked them more about their job.
It transpired that they worked on a contract basis for oil companies who do seismic surveys and exploration. Seismic survey work involves detonating explosive charges above the surface of the water approximately every 10 seconds. The resulting noise level for each is over 200Db. The shockwaves are monitored as they rebound, to build up a picture of the ocean floor.
The MMO's job is to survey the ocean surface during these surveys and call a halt to the operations if a marine mammal is seen within 500m of the vessel. Can this be seen as anything more than a token gesture?
In June 2007, on a trip to the Philippines, I personally experienced the underwater effects of a seismic survey. I was diving off Bohol when a survey operation took place 25 - 35 km to the north near Cabilao. I was stunned at severity. I first thought that someone was dynamite fishing nearby, but the perfect regularity of the shockwaves soon left me in no doubt about what was taking place. The underwater effects were enough to leave me with a severe headache for several hours after my dive. What would it have done to me if I were only 500m away! This has to stop!
------------------------------
The following is another account of the same seismic survey from a local Filippino fisherman.
'At the hearing on June 27, a Cabilao fisherman gave his testimony that the previous week he had gone spearfishing while the seismic survey was conducted in the seas off Sibonga, Cebu, more than ten kilometers away, and that upon diving he heard the underwater explosions, which at a depth of three fathoms were distinct and at which he began to feel vibrations in his abdomen and upper torso. At a depth of five fathoms the explosions were louder and the vibrations of his abdomen and upper torso grew stronger and at that moment he decided to surface. Since that incident he only went spearfishing on the other side of Cabilao Island, away from where the explosions came.'
extract from : Seismic Survey Chronicles (Part I) | PROCESS-Bohol, Inc. Official Website
----------------------------
I was limited to 250 words in my letter due to magazine restrictions. I can confirm though the feeling described in the other article. I felt my insides vibrate. I could literally feel the shockwaves pass through my internal organs. It is like nothing else I have ever experienced as well as extremely unpleasant and disconcerting.
