Slicks From August 30 – Back Again Today?

Tropical Storm Lee is long gone, the clouds are clearing, and the MODIS/Terra satellite image taken of the Gulf this afternoon seems to show a patch of dark slick located in the same place as the slicks documented by Bonny Schumaker on her August 30 overflight and confirmed on a radar image taken that same day.  The dark patch under the yellow marker is roughly the same size, too, about 14 miles x 5 miles.  And as before, there is no obvious connection between this patch of slick and BP’s Macondo well site.  Maybe it’s coming from something else.  We just don’t know yet.

Weather permitting Bonny may fly out there again tomorrow.

Detail from MODIS / Terra satellite image taken September 9, 2011 showing dark patch in same location as oil slicks observed on August 30.

Gulf Overflight and Radar Image (August 30) Now in Google Earth

Our friends at SarSea created an interactive Google Earth file (get it here) that shows the flight path of Bonny Schumaker’s August 30 overflight and the photos and video she took of the oil slicks she observed during that flight. Here’s an overview that also shows the location of the Macondo well – the source of last year’s BP / Deepwater Horizon oil spill – and the 23051 Site where we’ve been watching a chronic leak from a cluster of wells that were damaged by Hurricane Ivan waaaay back in 2004, overlain on an Envisat ASAR radar satellite image that was taken at about 11pm that night:

Bonny Schumaker’s August 30 flight path and photo points, overlain on August 30 radar satellite image. Envisat ASAR image courtesy European Space Agency.

August 30 Oil Slicks In Gulf – Closest Facilities

Tropical Storm Lee is drenching the Gulf and has put the kibosh on any Gulf Monitoring Consortium investigations for the next few days (even radar satellite images will be screwed up by the heavy rain and gusty winds), so we’ll have to wait and see what next week brings.  In the meantime, one of our Facebook friends (thanks Judson!) prompted us to give a little more info about the oil and gas facilities closest to the August 30 oil slicks (shown as orange dots on this image):

BP’s Horn Mountain platform – located in Mississippi Canyon Block 127 about 8 miles east-southeast of the August 30 slicks, this manned “spar” structure was installed in 2002.  It is connected to the Destin natural gas pipeline system that was shut down on August 30 because it was producing too much liquid.

Exxon’s Mica subsea manifold – located in Mississippi Canyon Block 211 about 8 miles south-southwest of the August 30 slicks.  This structure on the seafloor produces oil and gas that is transported by pipeline to the Pompano platform about 27 miles away.  This “subsalt” discovery marked a milestone in Gulf production.

We don’t have any information that either of these facilities is experiencing any problems, but they are both closer to the August 30 oil slicks than the BP / Deepwater Horizon site, which is about 15 miles away.

Radar Satellite Image Shows Oil Slicks Seen August 30

An Envisat ASAR satellite radar image of the Gulf taken at about 10:50 pm local time on August 30 shows distinctive slicks corresponding with video and photos taken during an overflight earlier that day by Bonny Schumaker / On Wings of Care.  This image is complicated – NOAA/NODC data buoys in the area recorded very low wind speed (2-3 meters/sec) when the satellite passed overhead, near the lower limit for oil slick detection.  The thin spaghetti-like strands of dark slick throughout this area are most likely tendrils of natural surfactants that commonly appear on low-wind radar images of the ocean surface.  But the size, shape and appearance of a 14-mile-long slick that seems to originate at the 23051 Site matches many observations we’ve made on satellite imagery since we discovered a chronic leak at that location. And the large dark patch at the location of the August 30 overflight apparently confirms Bonny’s observations with an area of slick covering about 122 square kilometers. Given a minimum observable thickness on radar of 0.1 microns under these low-wind conditions, that would represent a minimum of 3200 gallons of oil.

First, here’s what the August 30 radar looks like.  The Mississppi Delta is the bright birds-foot pattern on the left edge of the image.  Water is medium-gray; slicks are black:

Envisat ASAR image taken August 30, 2011 about 10:50 pm local time. Image courtesy European Space Agency.

Here’s the same chunk of image with markers showing the chronically leaking 23051 site, the Deepwater Horizon wreckage site, and the location of Bonny’s August 30 oil slick photos and video. Seafloor pipelines in yellow; recently troubled Destin pipeline shown in brown; active oil and gas platforms and other structures, including seafloor manifolds, are orange dots; natural seep locations are green dots:

Same area with features of interest marked. Image courtesy European Space Agency.

Zooming in, here’s the August 30 radar image again showing a distinct patch of slick about 16 miles northeast of the BP / Deepwater Horizon oil spill site.  Orange dots are active oil and gas production facilities (platforms, manifolds):

Detail from Envisat ASAR image taken August 30, 2011 about 10:50 pm local time. Image courtesy European Space Agency.

Same area with other features marked for reference (pipelines in yellow, natural seeps are green dots). The brown highlighted pipeline is part of the Destin gas pipeline network, operated by BP, that was coincidentally (?) shut down on August 30:

Detail from Envisat ASAR image taken August 30, 2011 about 10:50 pm local time. Image courtesy European Space Agency.

Here’s what the same patch of Gulf looked like on a radar image taken four days earlier, on August 26.  A small, 4-mile-long slick is visible just above the word “wreckage” – it’s about equidistant from a subsea manifold in the area and a couple of natural seeps, so either of these could be the source.  But this slick doesn’t seem related to the large patch observed on August 30:

Detail from Envisat ASAR image taken August 26, 2011. Image courtesy European Space Agency.

As usual, we’ll keep looking at this area as we get new imagery and information, and will let you know what we learn.

Oil Slicks Sighted Yesterday 16 Miles from BP / Deepwater Horizon Spill Site

Bonny Schumaker from On Wings of Care has been very busy flying the Gulf lately.  Yesterday she flew out over the site of the BP / Deepwater Horizon oil spill.  About 16 miles northeast of the spill site, she ran across extensive oil slicks that look to us like a lot more than the typical natural oil seep normally produces.  Check out her report with a photo gallery and video.

There is a known seep location less than 2 miles to the south.  The nearest oil platform is 8 miles to the east; the closest pipeline is >5 miles to the northeast.  MODIS satellite images taken yesterday afternoon showed nothing unusual in the area, and the most recent radar image for the site was taken back on August 26.  We’ll keep looking and let you know what we learn.

Oil slicks on August 30, 2011 about 16 miles northeast of the BP / Deepwater Horizon spill site. Photograph courtesy Bonny Schumaker / On Wings of Care.
Location of oil slicks documented by Bonny Schumaker on August 30, 2011. BP oil spill site (Deepwater Horizon wreckage) shown for reference.
Map showing August 30 flight line (pale blue), seafloor oil and gas pipelines (yellow), oil and gas platforms (orange dots), natural oil seeps (green dots), and BP oil spill site relative to slicks observed on August 30. Backdrop is shaded-relief bathymetry (seafloor “topography”).