The recent eartquake R 6 in Nicobar proved a great bonanza for the drillers in the Arabian sea.
The reflected waves from the cavern caused a diffraction pattern indicating good circularity and above all were able to generate a focal point of small raduis which is the center of the deep basin.
The time convolution integrals inicate that the
wave had to transverse a distance more than was first extrapolated. This will be good news as will enable the Owners to now drill near the circumfrence for field dilenantion.
Oracle: As you well know a location for drilling is selected based on a seismic survey using compressed air detonations from a towed array.
These reflected sound pressures are 230-250db at a distance of 1 metre from source.
The sea Noise is 80-120 db and intensifies with depth.
Earthquakes are 240db at 10-15 Hz within hundreds of kilometers from source. Because of a density change between the canyon wall and the resevoir rock there is a reflection that is used to determine the extent of the field from the time delay.
> I would hazard a guess that it is one of the few remaining sleeping giants.
That, combined with a brillant petro-geologist (JPR) with all "the right" contacts in India, undoubtly makes GGR well worth the premium people have been paying for the stock. Seems it just takes a while to "figure it out."
DeepEarthWorm: Welcome to the GGR message board. It's always good to receive additional geoscience input from informed posters such as yourself.
I am looking forward to reading your future posts as we watch the development of GSPC/GGR's Krishna Godavari Basin (KG Block) play.
bs572 does not come accross as one who is "the source" for rare tidbits of talk from India, but as one who has a good source over there. He, not unlike any of us, has to sort out the wheat from the chaff... which can be difficult at times. Some of it is bound to be baloney. Knowing that's probably the situation, I'm hesitant to be too critical of what little he posts here. Perhaps this merely affords him a sounding board, to help him sift through what he is hearing and to learn what sort of details can or do add validity to what he is hearing. If so, I say, post more of what your hearing, bs572. Together, with some of the other brains here, maybe some of it will occasionally give us either "an edge" or the reassurance of knowing more of what we really have here.
I've been watching this board with a mix of amusement and awe at the speculation of those with no concept of hydrocarbon plays (e.g. woody), those with mistaken concepts (e.g bs572), and those who with some real knowledge (e.g. Oracle).
I'm not a finance player ...all I have is my pocket allowance. I'm an earthworm and I assure you that there is no way you can delineate a field using a natural earthquake as a source... It is hard enough with conventional seismic where there are controls on the source and there are many receivers arranged in a planned regular array.
The Nicobar earthquake was located far away, with an unknown, uncontrolled source, there would be all kinds of other formations altering the waveform as it travelled, and furthermore, even if a vsp tool happened to be downhole its geometrical arrangement prohibits it from being useful in delineating anything latterally.
An earthquake derived or any other vsp could be used to calibrate seismic velocities and the resulting calibrated velocites could be used to fine tune previously collected seismic.
The stuff about the Arabian Gulf makes no sense. There are earthquakes in Iran all the time.. no need to get excited about some small earthquake in the Nicobar Islands. - And they are NOT used to delineate reservoirs.
It will be very interesting to see how this pans out. The KG basin and its plays are somewhat analagous to the West African basins -probably with higher sedimentation rates and higher pressures. I would hazard a guess that it is one of the few remaining sleeping giants.
The Deccan plays are quite exotic and completely different from anything I have heard of. The basalt will make them tricky to hunt using traditional methods.... but the play concepts seem sound.
mgrvik: Its a fact that drilling on the Coastal regions is at a halt because of weather conditions.
Howvever a lot of analysis and systems Engineering work is being done to get ready for the next phase which is dileanating drilling to fine tune the extent and capacity of the field.
In addition, GGR has another parcel and soon that will make the news.How soon; your guess is as good as mine.!
I have to admit that sometimes bs postings make my head spin and seem a bit bizarre. But here is the scary thing, call it knowledge or call it luck, he is usually on to something. Newcomers, don't take my word for it. Go back and check his posts.
slippery: I dont think anyone here appreciates the invaluable data nature provides in an earthquake record thru a zoned portion of the earths crust.
The entire area of any large Hydro carbon prospecting site has its impedance recorded both by aerial survey and local shock wave analysis. Unfortunately, this is neither homogenious or continuous. It is completely discreet data thru which impedance contours are drawn.
At the time of an earthquake, the sesimic recorders on the Drill platform record both the P and S wave and whats more the noise due to interference from the reflected waves from the boundaries of the gas resevoir. Beacause of low impedance in the gas/oil Resevoir the wave speed changes. The Graphs from the seismic recorders which are in the time domain have to be decomposed by Fourier analyses to give us the wave speeds and the different amplitudes. This data is then transformed into the space domain using the Convolution integral. Having this space , frequency and time data of the travelling pulse thru the Gas resevoir it is feasible to revise and update the impedance of the resevoir data and dilineate the boundaries and densities.
The perimeter of the gas field is important because if it extends beyond ones property there is need to quickly lower the resevoir heights to prevent ones neighbours from gaining the benefits. This is exactly what Mr Sadaam was intent on doing when he set up drill spuds on his side of the boundary near Kuwait.
Earthquakes are nature's gifts to oil prospectors and only the best know how to handle that.
A great bonanza? Well, if there ever was going to be a time or a hole to "get lucky" with, and "just so happen" to have testing equipment in the hole the same time as a R6 seismic event comes along... I suppose this would be the one.
Why do I always love to hear from you bs572?
Any word on the progress of the testing?
(Please consider posting more often than you do.)