And not far down the rabbit whole one finds: The author of the study often cited by oil companies for above narrative, felt impelled to publish a clarifying statement: https://luyendyk.faculty.geol.ucsb.edu/Seeps%20pubs/Luyendyk...
Maybe stricter guidelines against operational "routine" spills led to a reduction of the sticky spots, plausible?
You are projecting your biases. There was no "drilling is good for the environment" narrative. I was recounting an interesting fact about the environment there.
Many of these seeps are under considerable pressure as there is substantial natural gas mixed in. The seepage rate of each has been mapped and studied for many decades. It has long been observed that the introduction of drilling appears to substantially reduced the seepage rate at many of these underwater sites. Drilling wells significantly reduces natural pressure in these reservoirs, likely leading to the observed reductions in seepage.
[0] https://en.wikipedia.org/wiki/1969_Santa_Barbara_oil_spill
And some of it, if not most of it is not natural seepage but early environmental catastrophes in the 50s and 60s, particularly around Summerland.
(Source ex-resident)