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.

Problems With Major Gas Pipeline in Gulf

Yesterday BP shut down a major natural-gas pipeline in the central Gulf of Mexico because it’s producing too much liquid.  Today they announced the shutdown will be extended because of a potential tropical storm brewing in the Gulf. The Destin pipeline (here’s a nice map) is a major piece of offshore oil and gas infrastructure, collecting natural gas from platforms in the Mobile, Viosca Knoll, Main Pass and – wait for it – Mississippi Canyon areas.  The cause of the fluid buildup, and the type of fluids involved, was not reported.  It’s not uncommon for natural gas wells to also produce liquid gas condensate, an assortment of hydrocarbon liquids, in various quantities.

Oil and gas pipelines in the central Gulf of Mexico (yellow). Locations are marked for recently sighted oil slicks and the epicenter of a shallow (5.1 km depth) magnitude 3.5 earthquake that struck on February 18, 2011 (data from USGS).

Now allow us to indulge in some wild speculation:  IF there is seawater in the pipeline (and we don’t know that), it could mean that some part of the offshore Destin pipeline network has been damaged.  It may just be coincidence that one of the feeder lines on the Destin map, labeled R-13, is the closest pipeline to the oil slicks observed in the Gulf during an overflight two days ago, reported in our blog yesterday.  This is the yellow line on our map located about 5.7 miles northeast of the location where slicks were observed.  And there was a shallow, magnitude 3.5 earthquake very close to the Destin pipeline, just off the mouth of Mobile Bay, back in February.  Maybe the line got a little shook up by that small quake.  Is it possible that the slicks documented in this area on August 30 are in some way related to the shutdown of this pipeline?

Anyone have more information to share?

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”).

Marsh Fire Near New Orleans – Smoke Plume Over City

A quick update – yesterday’s MODIS satellite image shows the plume of smoke from a burning marsh blowing to the south-southwest, affecting a big chunk of the city of New Orleans and parts of the Jefferson, Lafourche and Terrebonne parishes:

Detail from MODIS satellite image taken August 28, 2011 showing smoke from burning marsh drifting over eastern and southern new Orleans.

Thick smoke was drifting yesterday over the communities of Chalmette, Braithwaite, Marrero, Galliano, Chauvin, Dulan and Theriot, then heading out over the Gulf, making a visible plume that extended nearly 300 miles from the source of the fire – much longer than the smoke plume we observed while the Deepwater Horizon rig was burning last April.