There is a great deal of concern about  the possibility that cracks in the well casing and rock formation surrounding the BP Gulf Oil spill could lead to oil leaking from cracks in the seafloor. The chronology of the IXTOC blowout in 1979 reveals that an underground blowout caused oil to leak from cracks in the seafloor.

Some experts deny that there are  cracks in the rocks surrounding the leaking oil well even thoughMMS documents show that BP has reports a series of cracks in the well casing and surrounding rock formation as far back as February.

It is true  that   BP has reported cracks in the sea floor and well casing and that there have been a series of well control events or blowouts that have occurred during the drilling of  the Macondo oil well that is now leaking millions of gallons of oil every day into the Gulf of Mexico.

The first report of cracks in the  rocks surrounding the well and in the well itself were in February and were concurrent with  the first in a series of “well control events” or blowouts.

Since the initial February blowout, according to the findings of an interim investigation released by congress there have been a total of 5 “well control events” or blowouts including the final blowout that led to the Deepwater Horizon rig explosion and collapse.

Time line from the interim investigation revealing that the BP well had 5 blowouts during the drilling of the well

Details of the time line of the Macondo Well Blowouts are as follows:

  1. February 17-23: BP reports cracks in well casing and leaking of hydrocarbons into the surrounding rock formation. It took BP 3 attempts to fill the cracks with cement before the well control event was brought under control.
  2. March 2-5: BP reported another well control event that took 3 days to bring under control
  3. March 8-14: BP reported a well control event that took 7 days to get under control. A series of BP internal emails released by Congress showed
  4. April 4-7: Well control event took 3 days to bring under control.
  5. April 20: Well control event leading to explosion and collapse of the Deepwater Horizon oil rig.

A recently released report from the the research ship Thomas Jefferson (Contracted by the National Oceanic and Atmospheric Administration (NOAA), which has been mapping oil and gas beneath the surface of the sea near the leaking oil, shows just how much worse the BP well blow out could be.

The report of the data collected by the Thomas Jefferson from June 3rd to June 11th revealed a series of oil and and or natural gas leaks have been found coming from the sea floor near the leaking BP Gulf Oil Spill well.

As Matt Simmons stated, the ship logs reveal that the Thomas Jefferson  was denied permission to investigate near the well, first being denied permission to get closer than 5 nautical miles and finally being granted permission to come within 3 nautical miles.

Daily Chronology

June 3-
Departed New Orleans 0600, transited down the Mississippi. Installed the new multi-sensor freefall fish and Turner crude oil sensor on the Moving Vessel Profiler. Tested the MVP off SW pass, verified data was received and logged and mechanical portion performed as expected. Conducted a shallow (20m) then a deep (600m) CTD cast to test winch, brakes, CTD and all sensors, and hone water sampling protocols. Began transit to spill site at 2200.

June 4-
Tied into NOAA Ship Gordon Gunter data by repeating three transects in the vicinity of natural gas seeps and taking a CTD at a site Gordon Gunter reported high fluorescence at around 1100m. Echosounder records were considered comparable. Interestingly, TJ’s cast did not show a comparable fluorescence anomaly. Additional sonar work in the vicinity of GU “hot spots.”Requested permission from SIMOPS to enter 5 NM circle to increase the probability of finding higher concentrations of oil from which to derive a sonar signature. Permission was denied. Last cast of the day (Cast TJ-07) showed a prominent anomaly at around 1100m with high CDOM and low DO. Recognition of pattern in sonar return hypothesized to be indicative of the anomalous water mass.

June 5-
Additional sonar work outside 5 NM, looking for patterns consistent with previous observations. First cast of the day (TJ-08) showed a prominent anomaly at around 1100m. Bow thruster inoperable part of the day, making precise cast placement difficult. Transfer of water samples to shore via crew boat. Permission granted to enter to 3 NM. Perimeter sonar and MVP line at 3NM.

June 6-
Block of transects conducted SW of wellhead. One CTD cast inside this area was negative. Similar acoustic signature not seen in this area. Returned to area of high fluorometer hits (TJ07, TJ08). Repeat cast in this area showed no anomaly. Took on water from crew boat. Zig-zag search pattern toward the SW, in the direction of the ADCP deep current. Faint acoustic anomaly detected along slope. CTD Cast 13 in this area showed traces of fluorescence and a distinct layer of low DO at depth. Departed area to transit inshore for 100m transect.

June 7-
Begin 100m transect, first east to Mobile, then west to the Mississippi Delta. Casts conducted about 6 times per hour. Refined on board processing and visualization tools. Took one cast in an area of anomalous fluorescence at around 40m depth. High CDOM and low DO to match. MVP casts continue to west.

June 8-
Decontaminate TJ hull, transfer samples ashore, exchange crew, press visit. Depart 1100 to begin baseline transects west. Additional MVP fluorescence anomalies noted. No time to investigate.

June 9-
Baseline transects moving west. Calibrated the echosounders so absolute values can be compared between vessels and over time. Slip ring failed on CTD winch, last cast of transects skipped to stay on schedule and fix the slip ring while transiting.

June 10-
Winch level wind failed on first cast of the day. Instrument recovered by manually moving the level wind. Cannot be repaired on board without appropriate parts. Remaining casts cancelled. Extra few hours spent finishing hydrographic surveys in fairways and approaches to Galveston.

June 11-
Arrive in Galveston 1000

3D Model Of Leaks On Gulf Of Mexico Seafloor Near BP Oil Leak Compiled From Data Collected By The Thomas Jefferson


Oil and or natural gas leaks (red and yellow columns) mapped by Thomas Jefferson, and by Gordon Gunter (purple cylinders) along with CTD stations showing high fluorescence or possible oil and gas anomalies (brown, green and white spheres). The Deepwater Horizon well site is in background (red cylinder) and distribution of Bottom Following Reflectors is represented by orange lines.

NOAA has said that the leaks on the sea floor graphed in the 3D model above “appear to be pre-existing seeps that occur naturally and are unrelated to the spill” and have labeled leaks as such in the Thomas Jefferson report.

But how NOAA came to the determination that these leaks on the sea floor are natural seeps needs to be questioned.

The report indicates that the ships that collected the data mapped the leaks on the seafloor with sonar with a simple alteration.

The altered sonar allowed the ships to track submerged hydrocarbons by detecting higher than normal levels of oxygen depletion.

The ships then dropped canisters in the water to take samples of the water at various depths to confirm the sonar anomalies were indeed hydrocarbons.

None of these methods would allow an actual determination that the leaks found on the sea floor were indeed natural or pre-existing.

It is also questionable why NOAA would label such seeps as “appear to be natural or pre-existing” while saying that the other anomalies found floating in the water column beneath the sea surface need further testing to verify that they are indeed oil and need to be confirmed as coming from the blown BP well.

Perhaps even more alarming is that the reports from the Thomas Jefferson seem to confirm a good part of what Matt Simmons has stated to the media including the existence of leaks miles away from the BP leak. The Thomas Jefferson was denied permission to investigate the source of underwater plumes it had located.

As the Houston Chronicle reports there are concerns that the series of blowouts that have occurred on the BP well would cause oil to leak into cracks in the surrounding sea floor.

Marvin Odum, president of Houston-based Shell Oil, the U.S. arm of Royal Dutch Shell, told the Houston Chronicle last week that the integrity of the well casing is a major concern. Odum and others from the industry regularly sit in on high-level meetings with BP and government officials about the spill.

If the well casing burst it could send oil and gas streaming through the strata to appear elsewhere on the sea floor, or create a crater underneath the wellhead – a device placed at the top of the well where the casing meets the seafloor – that would destabilize it and the blowout preventer.

Whether or not the leaks mapped by the Thomas Jefferson  found on the sea floor are natural or have been caused by the BP well blowout still needs to be determined.

But in either case there still exist additional concerns that the oil and gas leaking from the BP well could be finding a path into those leaks, natural or not,  making the situation worse as Washington’s blog notes.

Obviously, if there are natural oil or gas seeps nearby, there are already pre-existing channels up to the seafloor … so that may very well be the path of least resistance for the subterranean oil to flow up to the seafloor.

Therefore, if there were a substantial breach in the well bore, nearby natural oil and gas seeps could very well increase in volume.

Similarities to IXTOC Well Blowout in 1979

The chronology of IXTOC well blowout as presented in IXTOC I OIL SPILL ECONOMIC IMPACT STUDY clearly shows that a single underground blowout caused oil to leak from cracks in the seafloor.

In the spring of 1977, Petroleos Mexicanos (PEMEX) contracted Performaciones Marinas del Golfo S.A. (PERMARGO) to conduct exploratory drilling in the Chac area of the Bahia de Campeche in the Gulf of Mexico. PERMARGO contracted SEDCO, Inc. of Dallas, Texas in August of 1977 to supply a semisubmersible oil drilling rig under a bareboat charter (equipment, rig and supplies). In a separate agreement, PERMARGO contracted SEDCO for the personnel to assist PERMARGO in the operation of the rig. The location of the rig was (19° 20′ N, 92° 25′ W).

On June 2, between midnight and 0300 LT, the IXTOC I lost its downward hydrostatic pressure as the drill bit entered either a cavern or a highly porous section of the geologic formation. Engineers did not detect any oil or gas and elected to observe the well. On June 3, at 0230 LT, the oil well began to emit drilling mud. The workers activated the cut-off devices on the ocean floor, but these devices failed to work properly and did not stop the rapid upsurge of pressure.

The surge of pressure bent the drill pipe, and as a result, the crews were unable to control the well by lowering or raising the deformed drill pipe. Oil and gas gushed from the drill pipe to a height of 30 metres above the platform floor. Within moments, the platform caught fire and the crew abandoned the rig. The fire destroyed the SEDCO rig, causing it to collapse. Eventually, the rig sank to the ocean floor and caused more damage to the drill pipe and the well casing.

Initial efforts to cap the well did not succeed. The Red Adair Co. of Houston, Texas did succeed in closing the well casing and extinguishing the fire, but the well ruptured below the casing and caused a second blowout. Because of the danger to the ships, the fire was relit. Observers noted that the volume of oil and gas was larger and that the fire was brighter than before the attempt.

In September, Brown and Root, Inc. of Houston, Texas constructed a large steel cone, called the Sombrero. The Sombrero would be placed over the IXTOC well and be connected to a separater/diverter to isolate the oil from the water. The first time the Sombrero was taken to the location, it was damaged by high seas and had to be taken back to Houston for repairs. After repairs, the Sombrero was taken back out and installed over the well. The Sombrero did not function properly when it was in place. This was attributed to (1) the turbulence around the well head–which carried the oil around the Sombrero and (2) the escape of some of the oil from cracks in the sea floor that were adjacent to the well’s cracked casing.

During mid-June, PEMEX began drilling the IXTOC IA and the IXTOC IB. The IXTOC IB made contact with the IXTOC I in late November. PEMEX reduced the flow of the oil well by pumping steel balls and low density mud into the well. PEMEX was able to cap the well on March 25, 1980.

The Regional Response Team (Coastal Region VI) and National Oceanic and Atmospheric Administration met on July 13 and developed several plans of action : (1) To obtain samples of oil at the edge of the slick and gather wind and current data, (2) to conduct a vulnerability analysis of the Texas coast to determine the priorities of the environments and (3) to continue to monitor the oil slick movement. Several universities were preparing to conduct biological and geological analyses of the oil slick’s impact on the Texas coastline.

In late July, the available information indicated that the slick would enter the U.S. waters in early August. Clean-up equipment was deployed along the areas that were deemed to be vulnerable, and more equipment was en route. The U.S. Coast Guard boomed the Brazos Santiago Pass and several other inlets to the ecologically sensitive Laguna Madre area. Oil skimmers were deployed in front of the Brazos Santiago Pass, Port Mansfield, Port Arthur, and Port O’Conner.

On August 6 and 7 tar balls began to wash ashore onto Padre Island hotel beaches. Clean-up crews scraped the oil from the beaches by using Vac-Alls, graders, and front-end loaders. The oiled sand was dumped into a pit on Padre Island.

While the surface oil was controlled, divers found submerged oil in concentrations of up to 3600 particles per cubic metre in depths of up to 12 metres. The Coast Guard deployed a heavy nylon net to trap submerged particles at the Port Mansfield cut.

The oil stopped washing up on to the Texas shoreline by mid-September. The seasonal change in the wind and off shore currents began to reverse the northward flow of oil. Overhead reconnaissance flights indicated that there were large clear areas of water accompanied with smaller, occasional sheens of oil. The Coast Guard reduced the clean-up operation, but retained contractors on the scene until the end of the hurricane season. In mid-September, Hurricane Fredrick removed up to 95% of the oil that had accumulated on the Texas beaches. In November, tar balls were again sighted in the Corpus Christi and Brazos Santiago Pass areas. The Coast Guard reported that there were no new slicks in the area and suggested that the tides may have uncovered the weathered IXTOC I oil in the subtidal zone.

There is a great deal of conjecture on the effectiveness of the oil clean-up effort. In order to assess the environmental and economic impact of the spilled oil, a cooperative state and federal program was developed to determine the extent of the damages. The damage assessment program was prepared by the NOAA and the U.S. Environmental Protection Agency–Region 6. The cooperating federal agencies were the Bureau of Land Management, the Fish and Wildlife Service, the National Park Service, and the U.S. Geologic Survey. The cooperating state agencies included : The Department of Water Resources, the Bureau of Economic Geology, the Parks and Wildlife Department, the General Land Office, Corpus Christi State University, Texas A & I University, Texas A & M University, and the University of Texas. The program proposed to monitor the movement of the spill, analyze the rate of uptake of hydrocarbons within various resources, and conduct damage assessment studies for various resources. The schedule of the budget is 4.2 million–first year with the remaining 5.6 million over the following two years.

The BP well has had at least  6 such blowouts including the one that occurred during top kill which reportedly caused the well to blowout 1000 feet below the surface.

It should also be noted that Top Kill procedure performed during the Macondo blowout is equivalent to the capping of the well during the IXTOC blowout.

The Top Kill procedure in essence plugged filled the top of the well with mud which acted as a lid that contained oil inside of the well and prevented it from escaping from the top of the well.

So it appears that, as Rachel Maddow reports, the Deepwater Horizon blowout is history repeating itself all over again, just this time its much worse.

Source:  Alex Higgins

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