Posts Tagged ‘dp’

Enigmatic Critter

November 24, 2010

Hyolithids are a poorly understood group of critters. They first appeared in the Cambrian and became extinct during in the Great Dying(Permian-Triassic extinction) at the end of the Paleozoic. The Great Dying was the most severe crisis for the biosphere that the planet has ever experienced… about 95% of all species perished!

There are numerous hypothesis to explain the extinctions(google it), but it was probably a combination of several catastrophic changes that killed off most life.

A few hyolithids that were recovered from the Millersburg mb:

Someday, I will devote a post to the extinction event.

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The Legend of Sleepy Lagoon

October 30, 2010

The “headless” trilobite:

An I. gigas that was found in the Clays Ferry Fm. in Anderson Co. Kentucky. When I found it, it was posterior-dorsal up. Wow, I was excited! Oh well…

Neat-none the less.

Rant!

June 27, 2010

… that I have posted elsewhere:

The rig belonged to Transocean Ltm., but it was BP that submitted, and then altered, the design of the well that led to the blowout.

It was BP that chose the risky option of using only 6 centralizers on the final string of casing when their own analysis demonstrated that channels would be created in the final cementing of that casement.

It was BP that told the Schlumberger crew that a cement-bond log on that final cement job was unnecessary even though it was clear that the practice was standard operation in the completion of wells, and would have found some of the flaws inherent in the design that led to the blowout.

It was BP that chose to ignore industry standards when it chose not to fully circulate the drilling mud which would have given indication of dangerous levels of formation fluids in the mud.

It was BP that chose to not install a lock down sleeve that would have provided another redundancy against communication of formation fluids through the well head.

It seems apparent that BP chose a sub-standard design that ignored standard protocol in an attempt to save a couple of days on-site. Their attempt, if successful, would have saved only a fraction of the total cost of the well bore, and in relation to the profits that the reservoir hold, not even a mere pittance.

No one, that I am aware of, is angry at the British people, but we are furious at the criminal neglect of a company that has long flouted industry standards, and chooses profits over people… going all the way back to its days as the Anglo Iranian Oil Company.

Concessions??? Yeah, right!

Sponge Encrusting Worm Tube Encrusting Bryzoa

June 10, 2010

At a crinoid garden that I have been working for a couple of years, I found this curious example of an epibiont on an epibiont.

First, a trepostomate bryozoan found its home, then some cornulites worm tubes found the bryozoan inviting.

Finally, the sponge.

When it was alive, it had to have been pretty cool looking with the worms sticking out of the sponge.

Width of photo about 3cm

Mag x10

You know the scale

Since, it was found at one of my crinoid “gardens”, here is a double from the same locality. I have pulled about 50 crinoids from this site(too lazy to check my notebook), and the Archaeocrinus sp. out number Pychnocrinus sp. by a substantial majority(again, too lazy to check my notebook), So these are probably Archaeocrinus sp.

Many of the crinoids at this site appear to be weathered, but they are from fresh exposures??? They are found in a thin lens of mudstone within a calcarenite/calcirudite. They are early Late Ordovician. Some researchers postulate that the abrupt changes in facies in the Central Kentucky region is due to weird structural crap associated with tensional forces at the close of the Taconic Orogeny to the east.

So, that leaves me wondering… were these critters left high and dry in their shallow lagoon/inlet by a regression, and then covered by a transgression??? It seems plausible. They could have laid there for months, or longer, since there were no land critters to pick at the carapaces.

Do you have another scenario??? Let me know.

Anyway, here is the double.

Width of photo about 10cm

Here is one that I have shown before. It is from a fresh exposure, so it can’t be weathered.
Width of photo about 6cm

Structural Inversion and the Origin of a Late Ordovician Carbonate Buildup:

The Ordovician Earth System

Correlations Across A Facies Mosaic…

Kill Pill Vol.1

May 25, 2010

Tomorrow BP will attempt to “top kill” the well that is spewing-who knows how much-oil into the Gulf of Mexico(GOM). BP estimates somewhere around 5000 bbs/day are escaping from the collapsed riser and blowout preventer(BOP), but researchers at Purdue, using estimates from live feeds, estimate the flow somewhere between 40000-100000 bbs/day.

The Purdue results appear to be high; top producing wells in the GOM generate about 50000 bbs/day. This well’s location is in an area(Miss. Canyon Block 252) of the gulf that isn’t as productive as some other areas. So, I tend to accept BP’s estimates… within a margin of error, of course.

The “top kill” procedure involves pumping drilling mud into the BOP in pressures greater than the escaping oil and gas. The ideal is that the pressure from the pumps combined with the weight of the overlying column of mud will displace the hydrocarbons in the production string of casing from the well head to the base of the well, and then fill the casements-effectively blocking the leak. Cement will then be pumped into the string to seal the well… if all goes according to plan.

And, therein is the problem-nothing has gone according to plan. BP, and others, have speculated that the reason for the initial blow out was that a poor seal in the contact between the production casing and the protective casing at the base of the well. Apparently, the blow by was noted by engineers when mud pit volume increased out of proportion-well logs indicate that twice they stopped pumping mud in the two hours before the blow out!

In yesterday’s press briefing, BP noted that in finding cause of the blow out, the “investigation is focused on the following seven mechanisms.”

1. The cement that seals the reservoir from the well;
2. The casing system, which seals the well bore;
3. The pressure tests to confirm the well is sealed;
4. The execution of procedures to detect and control hydrocarbons in the well, including the use of the BOP;
5. The BOP Emergency Disconnect System, which can be activated by pushing a button at multiple locations on the rig;
6. The automatic closure of the BOP after its connection is lost with the rig; and
7. Features in the BOP to allow Remotely Operated Vehicles (ROV) to close the BOP and thereby seal the well at the seabed after a blow out.

Regarding 3 above: rumor has it that a well known, and very expensive geotech firm was on the platform to do cement-bond logs, and that in a hurry to get off site(so the completion crew could move in???), BP’s top guy on-site put a stop order on the c-b logs. One thing is known-the geotech firm confirmed that they pulled their people 6 hours before the blow out- which was 14 hours after the final cement job for the seal started pumping.

There are other rumors floating around that the well was “kicking”… hard, and that for that reason, a “dump kill” was recommended hours before the blow out.

I guess that we will find out in Congessional hearings.

There are a lot problems with the “top kill” plan. Some have speculated that the mud, under those pressures, will fracture the formation, and that this will lead to greater flow at the base. Fracking wells is a common procedure to increase production in reservoirs, but as the sediments in the gulf are very permeable(around 30%), and barely consolidated, it doesn’t seem that if the formation does frak, that it would a problem.

Though, a real possibility is that blockages in the string will force the mud out the BOP, eroding what constraints are inhibiting the flow. Another danger could be a blow out in the containment string near the surface… if the seals are bad, and there are blockages, the mud could force its way into the containment nearer the surface where that part of the string doesn’t generally encounter those types of pressures.

BP estimates for success are 60-70%. If unsuccessful, a “junk” shot will be attempted in which various sized rubber balls will be injected into the system; If that fails, an attempt will be made to cut off the top of the damaged BOP and affix the Lower Marine Riser Package(Top Hat) to the clean surface.

I wish the crews luck tomorrow. Hopefully, by tomorrow night the well will be sealed… but I doubt it. From the opinions of engineers and geologists, that I have read, this thing might be flowing until the relief wells are finished in the late summer.

Note: I am not a petroleum geologist, and I do not work in the industry. If I have misconstrued anything, or is there is more to add, let me know in the comments.