Statement by Prof Harry Roberts of Louisiana State University's Coastal Studies Institute
In the northern Gulf of Mexico, the geology of the continental slope promotes the release of hydrocarbons from the seafloor, according to Harry Roberts, Boyd professor emeritus at Louisiana State University's Coastal Studies Institute. "Using three-dimensional, seismic data, over 22,000 natural seep sites have been mapped in the region, including quite a few in the vicinity of the Macondo well site," he said last week. Natural seeps can be active for years, constantly releasing gas and crude oil.
Roberts, who has been studying the northern Gulf's natural seeps since 1985, said he believes the blowout at the Macondo well had little effect on natural seep sites in the area.
In another opinion from LSU, emeritus professor of environmental sciences Ed Overton said "My understanding is that seeps caused by drilling and caps are infrequent relative to the large number of natural seeps in the Gulf."
~~~ end of quote
Reply by BK Lim (15 May 2012).
"Natural Oil Seeps" afterthoughts are being actively expounded by obviously pro-BP scientists and industry experts, in the futile attempts to absolve BP of billions in liability for the obvious regional environmental damage, economic disruption, slow genocide and untold wildlife suffering from the BP Macondo Oil spill disaster. Realistically, how could one shallow gas well blowout have caused so much damage?
There had been tens if not hundreds of shallow gas blowouts that had occurred in the history of the exploration industry. None had been as tectonically damaging as this "single gas blowout" fairy tale BP is trying to ram down our throat. Everyone of the industry experts who had actively abetted BP in this heinous crime of mass destruction (if not the crime of the century), should be thoroughly ashamed of themselves for prostituting themselves to the evil BP corporation.
Look at the big picture. Don't be like the blind men of Hindustan arguing over the elephant. BP want us to focus on the blowout on the night of 20 April 2010 when in reality, it was the series of deliberate powerful detonations which could only have produced such far-reaching tectonic damage beyond the 20-30 miles radius of the Macondo well location. The irrefutable evidence are presented in Facebook pages, Newsvine columns, Wordpress blogs and many other alternative news webpages by supporters of the Gulf Truth movement.
None of the main stream media has the guts to cross BP's line in the sand. So much for the free press and the truth in the Land of the Brave and Free. For more than 2 years, the Emperor has been wearing no clothes. Yet millions had been spent on bull@!$%# PR praising the Emperor's invisible fine golden robes. Humanity cannot be saved from such wanton needless and deliberate catastrophic disasters, if there is no will to fight such evil deception.
No doubt, there are thousands of natural seeps in the Gulf. These are called Natural Seeps precisely for their slow and limited volume discharge rate. For larger volume leaks, we call them "gas/oil columns" as the pressured releases push them several tens of metres above the seabed against hydrostatic pressure. Geology and geohazards geophysics are commonsense logical sciences. Unnatural seeps or a better term Instantaneous Massive Discharge (IMD), are hundreds to thousands of times larger in volume than natural seeps. Unlike natural seeps which can leak for years, the IMDs are normally short duration phenomena, lasting from a few minutes to a few hours.
The IMDs typically die down rather quickly to columnar discharges which then slowly weaken to the "pseudo-natural seeps" (continuous or periodic). In part III, we will discuss further the migration of oil to the shallow traps and how to differentiate between the natural seeps prior to the detonation on 22 April and the induced Unnatural seeps thereafter.
We seldom hear of massive oil sheens (tens of sq. miles) caused by real natural oil seeps especially in deep water. Due to the great depths (>3,000 ft) the tiny and low volume natural seeps would have dispersed and not discernible at the sea surface.
The 10 miles long sheen between Shell platforms (Mars & Ursa) reported on 12 March 2012 was an induced Unnatural Seep or more correctly a small IMD. Anyone who described it as a "natural seep" has serious fundamental flaws even if they do carry a PhD to their name. This will be explained in part III. The reasons are fundamentally simple and self-evident (field observation).
Were there any report of natural seeps causing tens of miles long sheen before the BP Macondo Oil Spill disaster?
We will discuss more in Part II.
If there had been quite a few natural oil seeps in the vicinity of the Macondo well site as claimed by Prof Harry Roberts, USCG, NOAA and others, why did BP not map and locate them as required by offshore regulation and for their own safety requirement?
Did BP not care what they drilling into? Perhaps not. After all BP rushed to drill the Macondo well without adequate reservoir mapping and evaluation less than 6 months after acquiring the lease. There was no new 3D seismic data acquisition. In fact everything BP did on this so-called exploration well (we prefer to call it the sacrificial lame well) was totally opposite of BP's other 5 deep water exploration wells applied for in 2009.
Apparently these 5 exploratory wells which adhered to industry standard practices, were drilled safely while the only lame well which broke all the safety rules and ironically awarded the MMS Safety Award on the day of the explosion, blew. There are numerous other safety violations as well. It does not make any sense unless BP acquired the lease to blow it up in order to cause the primary objective of flooding the Gulf with oil. Then only it makes a lot of sense.
BP skipped the mandatory high resolution geohazards survey.
BP's safety assessment stated they were drilling 1000 ft away from the edge of a low-relief escarpment when in fact, the well location was on the mid-slope of a 7 x 4 km L-shape major escarpment which was a major indication of the geohazardous problems ahead.
In BP's one page summary, there were more than a dozen fundamental errors. It clearly showed that Safety is BP's least priority not BP's top priority as BP constantly misrepresented to BP's investors and shareholders in their annual reports.
In many countries, it would be a federal offence not to map the active gas/oil seeps prior to drilling. If indeed there were natural gas and oil seeps, it would also mean that the proposed well location was indeed very risky to drill. The most prudent standard practice would be to shift the well location to safer ground (a safe location at least 1 km away). If BP did not do that (as required by BP's own and International Safety Policy) then BP is guilty of gross or even criminal negligence. Exploration wells can normally tolerate such shifts since they are only exploratory.
If BP ignored the "Safety First, Move to Safe Location" prudence, then at the very least BP should have alerted MMS, the insurance company undertaking the risk coverage and the drilling crew who had to risk their lives, by highlighting the drilling risks posed by these shallow gas/oil seeps. By not doing so, BP had fraudulently failed its own OMS, the very program BP touted as the foundation for BP's new improved safety record.
By keeping silent and downplaying the gas hazards as negligible BP is guilty of insurance fraud and endangering the lives of all onboard the drilling rig without precautionary warning of the dangers they were about to face. BP's safety assessment also did not specifically address the potential drilling hazards posed by the presence of shallow hydrocarbons.
BP downplayed it as "the risk (chance) of encountering shallow gas". There is a world of a difference between the "high risks of drilling in close proximity of active oil seeps" and the "risk of encountering gas". BP did not assess the drilling risk at all. BP merely stated the chance (risk) of hitting gas in the sand-prone layers which might or might not be a drilling risk.
In BP's downplayed safety assessment, the probability (risk/chance) of hitting shallow gas is Moderate (about 50%) for two-sand-prone sequences in Unit6 and Low (<25%) in Units 4 -6 and Negligible (<10%) from seafloor to Horizon 60. In other words the chances of hitting shallow gas is negligible to moderate with the implication that even if gas is encountered it is limited to 2 disconnected sand-prone sequences.
Now isolated gas layers by their definition pose no serious drilling risk. For many fundamental reasons, these isolated sand-prone gas layers would have limited supply (recharge) and low volume-pressure. Further BP had stated so confidently that the well bore would not intersect any fault down to 5292 ft BML. So where is the hydraulic connection for quick recharge from the reservoir, a few thousand feet below?
BP's safety risk assessment (or the lack of it)
BP, through their schills and proBP scientists are now using the natural seeps, natural faults and natural "EVERYTHING" to absolve BP from further liabilities of the environmental mess they had created not from the
- "normal gas well blowout" on 20 April (21:45 CDT) which they intentionally triggered
- but from the sub-seabed detonation within the 3rd well at approx 17:22, 22 April and
- the small nuclear detonation above 18,000ft BSL within in Relief Well C at approx 23:33 CDT 1 Aug 2010.
The Instantaneous (gas/oil) discharges recorded at the USCG home base at Mississippi Delta (50 miles away along the regional NNW-SSE buried fault zone), massive oil slick stretching for more than 20 miles from the Macondo well and the oil slicks found offshore Florida's west coast were testaments of that 22 April detonation not the 20 April well blowout BP would have us believe.
It is unbelievable that BP's inconsistent and discrepancies-packed "1-well-3 leaks on a single Riser story" could fool so many of the world's leading scientists and industry professionals. Even the average Joe Public find such an illogical fairy tale hard to swallow. http://bklim.newsvine.com/_news/2012/02/10/10376833-part-1-the-farcical-3-leaks-on-the-broken-riser-story-cont
By the way oil seeps are rare and rarer still are massive oil discharges. If massive oil are found at such shallow depths beneath the seafloor, why did BP have to drill so deep? Their original target depth was 20,000 ft BSL or 15,000 ft BML.
Now, consider the realistic geohazards assessment if indeed gas/oil seeps were already seen on the seafloor.
If indeed natural oil seeps were actively seeping in the vicinity of the proposed well, that well would have to move location. No question about it. As drilling in the vicinity of the oil seeps would be extremely risky with unpredicted consequence or at the very least a nightmare well with massive circulation losses and humongous cementing problems. With massive oil at such shallow depths, the seismic data would be very limited in depth penetration. There is a lot more geological implication of shallow natural oil occurrences. Would Art Breman and Prof Harry Roberts really want to risk their professional credibility by pushing for the shallow oil occurrence at the Macondo prospect? Think about it.
It is thus criminally negligent for BP to ignore the dangers if indeed natural oil seeps were present. This is a double edge sword. In trying to absolve BP from the liability of the continuing leaks caused by BP's deliberate detonations on 22 April and 1 August 2010, BP is admitting to deliberate genocide and the crime of mass destruction.
Even the most powerful gas well blowout will not cause seafloor damage beyond a few kilometres. (more of this in part II). USCG reported a few isolated oil slicks immediately following the first well blowout on April 2010. These have to be checked out considering the number of documented lies USCG had been caught with for colluding with BP. But until 24 April 2010, no massive oil slicks were ever reported. Then suddenly on 25 April (less than 3 days after the massive sub seabed detonation at approx 17:22 CDT 22 April 2010), the satellite photo recorded more than 580 sq miles of thick oil slick.
How could such a massive oil slick over such a large area have originated from a 10-inch well which Art Berman had said was impossible to exceed 100,000 bpd? By their own recorded statement, BP had estimated the volume of spill to be between 64,000 to 110,000 barrels per day.
Much of the oil were discharged almost instantaneously from shallow traps beneath the Quaternary Deposits at the edges of the shelf, domes and fault zones. The oil had been accumulating since the start of the disastrous and indiscriminate drilling by BP in February 2010. The proofs were inadvertently recorded by so many events outside BP's PR bull$hit.
For example the mortality rate of the dolphins started to rise in Feb 2010 (2 1/2 months before the blowout) peaking in March- early April. This was the period of heaviest losses of drilling mud and cement to the seafloor, drilling through the GWSF zone not only once but 3 times in 3 wells. In March 2011, the mortality rate was again the highest coinciding with the IMDs that followed the Japan 9.0 quake on 11 March 2011. There were tens of miles of slick due to the IMDs not from the slow, low volume natural seeps. It is absurd even to suggest.
The huge quakes that occurred in Chile (8.8M, 27 Feb 2010, 06:34 UTC) and in Haiti (7.0 M, 12 Jan 2010 21:53 UTC) before the 20 April 2010 did not produce any oil slick even though they were nearer to the Gulf. This proves that the oil had not yet leaked from the Macondo Reservoir, migrated to the shallow traps beneath the Quaternary Deposit. Surely the detonation on 22 April 2010 could not be more powerful than these 2 quakes.
Thus while the oil had leaked (since March & April 2010) from the Macondo reservoir and accumulated in the shallow sub formation and Quaternary traps, it was a gradual gas-brine erosion-led process. The trapped shallow oil did not have sufficient pressure to overcome the hydrostatic pressure of both the sediment overburden and the water column. So the oil stayed trapped beneath the sediment cover. Even the gas blowout at the Macondo well on 20 Apr 2010 did not trigger their IMD. That confirmed how insignificant the gas blowout was in relation to the widespread massive tectonic damage that is apparent now.
Now why did BP and the proBP experts all hyped up such a small normal gas blowout by conjuring up high pressure, free flowing oil through the well when the base cement had not even breached yet? They must have been fed the technical details of the planned bottom-hole blowout prior to the "explosion" except that Mother Nature intercepted to produce a shallow gas blowout instead.
Details of the Macondo shallow gas blowout are given in part II of this article.
Having failed to produce the massive oil spill as planned, BP had no choice but to blow up the well at approx 17:22 CDT 22 April. That second powerful detonation breached the base cement to unleash the massive free flow of oil from the Macondo reservoir. That was why Adm Mary Landry said there was no oil emanating from the well head, BOP and the immediate vicinity of the well on the morning of 23 April 2010. The 25 April satellite photo showed that the oil did not leak only through BP wells. They came from IMD from the shallow traps at the edges of the Shelf and the salt domes. The pattern of the slicks also proved that these massive shallow oil accumulations could not have existed in January 2010 prior to BP's drilling activities from Feb - April 2010.
After the Gulf had been cleared of the surface slicks in Nov 2010, any new major slicks would have to be IMD from new oil traps that started accumulating since then. It is significant to note that BP spent months grouting the faulted leaks around the Macondo wells so that any new leaks would spread further away. BP want the public to stupidly look at well A as the only leak as the late Matts Simmons had warned.
Gas Seeps are less dangerous but with brine, the combined fluid erosion pave the way for oil migration to follow.
Gas seeps are less dangerous for many fundamental reasons which I will not go into details here. Still as I pointed out in my article published in
July 2010 and in my papers published in GSM before that, the gas-saturated weak sub-formation (GWSF) zone can be quite problematical in sealing the top hole section. At the very least, the poorly sealed top hole annulus will continue to lose drilling fluids (mud, cement & slurry) to the water column and the annulus grow bigger with erosion over time.
In the worst case scenario, the gas-saturated formation might be damaged by high pressure mud and subsequently collapse into the well bore. This happened in both well A (4000-5000 ft BML) and well B (8000 ft BML)
4. How BP’s Macondo Well blew.
Figure 4a illustrates a normal sealed (cemented) top-hole section of a well. Figures 4b to 4d illustrate the difficulty in sealing the top-hole section passing through a GWSF hazards section. The enlarged and irregular well-bore also acts like a vertical conduit connecting the open fractures (fissures) in an already fractured formation.
Loss Circulation is common as the heavier high pressured mud invades the fractured formation and in the process forces the formation fluid and gas deeper (laterally) into the formation and upwards into the overlying permeable sandy layers. But this is only a temporary equilibrium. As more gases and formation fluid are squeezed out and displaced, more drilling mud will invade the fractured formation. The GWSF zone in the vicinity of the well bore essentially becomes a hydraulically connected extended gas-charged pressurized (EGCP) zone; the extent of which depends on the drilling practices and geological nature of the GWSF hazards zone.
Drilling mud will be forced back into the well whenever the pressure in the well drop below the charged-up pressure in the EGCP zone and vice versa. This is the nightmare scenario drilling through the GSWF hazards zones.
Even if a well manages to “drill thru and safely cement” the top-hole section, the poorly cemented top-hole section in a hydraulically connected EGCP zone will continue to act like a dynamic “spring-loaded” charging system; just waiting to blow on the slightest mistake.
Despite the nightmares, Transocean’s drilling crew managed to control the well until it reached their targeted depth and oil reservoir. Displacing the drilling mud with seawater (too early) was a mistake that triggered the blowout.