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Ophiolite

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Everything posted by Ophiolite

  1. All oil and gas wells employ casing and cement for the reasons previously noted. I am bemused by your belief that diagnosis is not a prerequisite of treatment. It is possible to adopt a Luddite position and oppose any technology that carries with it risk (i.e. all technology). If you wish to have the benefits of technology - and your use of the internet suggests you do - then you need to ensure that the technology is applied in as safe a manner as practical. That means the mechanisms of any undesirable outcomes are identified and mitigated. Therefore the cause of any aquifer contamination must be identified.
  2. When you've spent as much time investigating the Alien story as I have you finally get to the bottom of it. You find there a melange of hoax, self delusion, poor education, mental illness, weak humour, obsession and foolish error. You then, if wise, climb out as rapidly as possible.
  3. How many threads do you intend to start on the same topic darryl88? What is your aim? The majority of the mechanisms you have spoken of are recognised by the biological consensus and, indeed, were developed/discovered by the biological consensus. It is not earthshattering news to learn that evolutionary theory ..... evolves. Why do you think it is?
  4. As an outsider, but one with a long term, first hand knowledge of the US, the posts above have an unpleasant hint of gloating about them. The US and the world continue to face major issues of economics, security and environmental change. Solutions will not be found through advesarial name calling, but through bipartisan cooperation and attitudes that reflect an understanding of the other point of view. ..... No matter how little effort may appear to be made by 'the other side'. It would be nice to think some of that effort could be expressed here on this forum.
  5. Over many years of conversation, reading, debating, thinking, contemplating and other active and passive thought processes I have arrived at a world view. As a devout agnostic this is not a religious view, but it would not be out of place to call it a spiritual view. I suspect (very strongly suspect) that the importance of this worldview to how I conduct my life is directly comparable with the importance of their belief system to religious believers. I am quite certain that this worldview informs everything that I do, so that when I am practicing engineering analysis (which is as close as I get to doing science) I am at the same time doing (employing) my worldview. I see no reason that one could not, therefore, do science and religion at the same time. Indeed, I find it difficult to see how this could be avoided. As a former Christian I can see nothing in the protestant version of Christianity that would contradictory to doing good science. Indeed, the reverse is true. My former Christian viewpoint and my current worldview would both promote effective scientific investigation. I am puzzled by those who see this as a problem.
  6. I do hope you realise that any such selection will be subjective, unscientific, and of value only in as much as it provides you with a focus for your art work. On that basis and only that basis here you are: Cambrian - Trilobites Ordovician - Graptolites Silurian - Brachiopods Devonian - Ostracoderms Carboniferous - Labyrinthodontia Permian - Therapsids Triassic - Cynodonts Jurassic - Archaeopteryx Cretaceous - Triceratops Tertiary - Angiosperms
  7. If we promised to accept your word that all of this is true would we still have to read the details?
  8. Would you agree that the correct way to distinguish between the ideas that are 'true' and those that are 'false' is to require evidence in support of the proposed idea that is superior in some way to the evidence for the currently held idea? Since you seem to be a reasonable person I shall anticipate that you will reply 'yes to my question. Now, in the world of science how is a new proposal greeted? I work in engineering, not science. I'll tell you how new ideas are greeted here: with derision, condemnation and demands for secure evidence that they will generate greater profits. If the ideas are any good they survive that process. Now do you think in science we should somehow treat an idea and its proposer with kid gloves? We should be gentle and understanding and compassionate? Why? How does that help the idea? How does that help the proposer? How does that help science? How does that help humanity? I do a fool no favours by granting them the title genius.
  9. Practically all oil and gas wells contain multiple strings of casing. Typically the first string is there to prevent collapse of poorly consolidated surface sediments. The next string may be placed to protect aquifers. subsequent strings seal of troublesome formations: mobile salt' date=' overpressures, vuggy limestones, hydrophilic shales. Only the last string, the production string, penetrates the reservoir. So, in a typical well there are mutliple strings of casing and associated cement to provide isolation and protection. This turns out not to be the case. Most productive shales lie beneath unproductive shales, or other zero/low permeability rocks, such as evaporites. I am sure that this may occur. However, while we have instances of contamination of aquifers by hydrocarbons from completely different sources, we don't seem to have instances where it occurs as you are proposing. I stand ready to be corrected on this point by reasonable evidence. To justify that opinion you would need to submit more facts than you have to date. If we wish to prevent problems do you not think it wise we determine the root cause? If, as I suggest, the primary issue is of insufficient attention to casing and cementing design and implmentation rather than the fraking process itself then we really need to know that: it is a central distinction. Operators are obliged by law and by strong desire to avoid lawsuits to consider the integrity of aquifers. Where is your evidence that the operators did not employ due diligence? So let's stop driving cars, watching TV and flying to Cancun for holidays.
  10. A nice summary of the scientific method, silica. Unfortunately it seems that lovelife11 was a drive-by poster. His (her) venture into science and philosophy seems to have ended, at least for the moment.
  11. 1. Please provide citations of peer reviewed research that confirms that there is "extensive photographic evidence of unknown flying objects disobeying current physics laws". 2. Please explain why you believe any eye witness testimony is reliable. Again, citations to peer reviewed research demonstrating the value of any eye witness testimony would be appreciated.
  12. In addition to the information you have gleaned and Moontaman has supplied, you should point out to your friend that there is no requirement for Martian methanogens to behave like terrestrial ones, or to have the same metabolic pathways. I am from that minority who think the Vking labelled release experiment probably did detect life. However, I find the atmospheric methane no more than intriguing: I don't think it adds to tthe probability of Martian life.
  13. It's three decades since I did machine language programming, but my recollection is that numbers were expresses as binary floating point. A portion of the computer word is reserved for an exponent.
  14. I think it was established more than a decade ago, via simulation, that there were plenty of stable planetary orbits in binary systems.
  15. Those readers who routinely read research journals for their studies or work will be aware of the sub-text that is sometimes present. Such sub-text may subtly question current paradigms, or be a veiled attack on other researchers, or hint at deeper implications of the research, or place caveats on the findings of the paper. Perhaps the most famous example is Darwin’s single line in On the Origin of Species: “Much light will be thrown on the origin of man and his history.” That is not so much a tangled bank, as the seeds of a tangled web whose tendrils still extend today towards the light. What started me on this line of thought was stumbling on this brilliant sentence in the abstract of a paper on planetary accretion discs. “Disc modelling is in some sense more of an art than a science, and since a steady disc can be constructed for almost any combination of viscosity and radiation process the possibilities for extending one's list of publications are almost endless.” Delightful: one senses a sly dig at rival researchers who have pursued exactly such a course. So, do you have other examples of such sub-text that might amuse, shock, or enlighten? If so, post away.
  16. 100% means all of the entity or number observed/under consideration. 100% of 7 is 7. 100% of pi is pi. Therefore your questions are of no substantive meaning.
  17. This sounds interesting Ziven. Several years ago I played around with expressing several theories of behaviour in equation form. I did not intend this as a serious attempt to mathematically analyse behaviour: I was looking for a shortcut to develop character behaviour in a novel I was working on. Your approach seems more deliberately limited and therefore more practical and more serious. I look forward to your further posts on the matter.
  18. Steven, are you aware that practicing scientists in their training are required to come up with new ideas, not simply indulge in rote learning? Are you aware that an academic reasearch scientist's career depends upon him generating and demonstraing new ideas? Are you aware that a scientist in industry retains her job only on the basis that she produces new ideas for her employer? In short, your understanding of how science and scientists work is faulty. To Anilkumar: I have been engaged with several science forums for many years. In that time I have witnessed hundreds of proposed 'theories' which were either self evidently wrong, or fairly rapidly were shown to be so. There is a character to the way such ideas are presented that raises doubts at the outset. Repeated exposure to the association of that character and the poor quality of the 'theories' leads one to the reasonable position that most (almost all) 'theories' proposed on science forums are bollocks. Would you agree with this assessment?
  19. I don't ban anyone, nor do I set the rules for this or any other forum. If I did, then I think being consistently rambling, silly and boring would be good reasons to ban someone. Do you think we should encourage loose thinking, ill considered ideas and intrinsically dull posting? Do you seriously welcome such posts? Or do you think that illusio's posts were cohesive, thought provoking and intriguing? I was not attacking illusio, but the quality of his posts. The distinction may seem to be a small one, but it is - I think - important. If illusio feels he has been attacked, he is free to subscribe to any other science forums I participate in and send me a pm. I have no idea how you arrived at this conclusion. I have made no estimation of the members of this forum. I have identified rambling on the part of one member in more than one post and in more thant one thread. That is an objective observation. I have not extended that observation to a deduction concerning the capacity of the membership at large. The more I think on it the more bizarre I find your suggestion that I have done so. Again, you seem to be confusing an observation concerning a post with an observation about the author of the post. If I wished to insult illusio I would have done it when I was sure he was on hand to read the insult.
  20. Well Michael, I have a comment. I noted this thread was still running and came here in order to post a question: why the heck are we entertaining such utterly pointless nonsense from someone incapable of delivering a single coherent, intelligent, interesting contribution to the forum? If you think his posts had value and were deserving of attention please pm me. I can give you the url's of forums where such nonsense is celebrated.
  21. We're human. We don't do things like that.
  22. Your understanding, as you noted, is incomplete. You have correctly identified some key contrasting characteristics of shale gas and conventional oil and gas reservoirs. The latter have comparatively high porosities and, crucially, high permeabilities. The former have modest porosities and low permeabilities. The objective of the fracturing is to improve that permeability. Increasingly conventional oil and gas reservoirs are smaller and of lower permeability, so that multiple wells and horizontal wells through the reservoir are needed to achieve adequate production levels. The technologies developed for these wells is now being applied to access the shale gas plays. Your concept of the mobility afforded the hydrocarbons by fracturing is a distorted one. The point I emphasised in my opening post applies here - just as it does to conventional oil and gas reservoirs. It is essential that through proper planning, and implmentation of that plan, that the casing and cementing program, and the completion program, properly isolate the reservoir from other portions of the well. Fracturing per se does not give an unlimited licence to the hydrocarbons to migrate indiscriminately. These are not trials. Companies are assuredly not losing money. (I'm sure as in any business venture there are exceptions.) You do not achieve a 600% increase in shale gas output through conducting trials. You do not have hundreds of rigs engaged in drilling into shale plays in the Williston Basin, the North East states and the Permian Basin as part of a trial.
  23. But I am a Dallas Cowboy fan and my daughter was born in Dallas, which would make her spawn ^(-2). And I lost $666 over a number of games betting they would come back and win in the last two minutes from a seventeen point deficit. We destroyed the Oilers by thought power alone. The Texans are next. .
  24. Not exactly - and I stress this is just my opinion, but it is an opinion informed by thirty years in the drilling industry. The frakking has almost nothing to do with it. I suspect insufficeintly robust casing and cementing programs, or ones that are not properly implemented are the root cause. These should isolate the aquifers from any other part of the borehole, including the production zone, which will also be isolated. If the cement job is poor then migration of fluids could occur between any zone and any other. High pressure gas would naturally tend to migrate upwards, and eventually penetrate the aquifer. The solution, if my suspicion is correct, is then to raise standards on cementing processes rather than to question the frakking. For example I hear vigorous objections to the fluid used to fracture the shale. Frankly this is irrelevant. If the job is done correctly, that fluid will never come anywhere near the aquifers. If it does reach them, then no matter how benign it is the process is faulty.
  25. Between 2006 and 2010 shale gas production in the US increased by 600%. The process involves drilling into gas rich shales then fracturing these to provide sufficient permeability to bring production rates up to commercially viable levels. Gas shales have relatively low porosities, typically less than 10%, and very low permeabilities. Much of the gas is adsorbed on the clay surfaces, though some is present in the pore space. Hydraulic fracturing at very high pressures generates very long fractures that penetrate deep into the formation and provide a conduit for free and adsorbed gas to reach the borehole and production tubing. Claims have been made that the fracturing has led to contamination of much shallower aquifers. Although I have not studied specifics of individual applications, I have provisionally concluded - based on industry experience - that if contamination is occuring then, in most instances, it will be a consequence of poor well planning (casing setting depths, grades, cement program etc.), or poor implementation of that plan, especially a poor cement job, rather than a direct consequence of the fracturing, or fracing process. This article from PNAS offers another possible source, a natural one, for aquifer acontamination. Warner, N.R et al "Geochemical evidence for possible natural migration of Marcellus Formation brine to shallow aquifers in Pennsylvania." PNAS July 24, 2012 vol. 109 no. 30 11961-11966 Abstract The debate surrounding the safety of shale gas development in the Appalachian Basin has generated increased awareness of drinking water quality in rural communities. Concerns include the potential for migration of stray gas, metal-rich formation brines, and hydraulic fracturing and/or flowback fluids to drinking water aquifers. A critical question common to these environmental risks is the hydraulic connectivity between the shale gas formations and the overlying shallow drinking water aquifers. We present geochemical evidence from northeastern Pennsylvania showing that pathways, unrelated to recent drilling activities, exist in some locations between deep underlying formations and shallow drinking water aquifers. Integration of chemical data (Br, Cl, Na, Ba, Sr, and Li) and isotopic ratios (87Sr/86Sr, 2H/H, 18O/16O, and 228Ra/226Ra) from this and previous studies in 426 shallow groundwater samples and 83 northern Appalachian brine samples suggest that mixing relationships between shallow ground water and a deep formation brine causes groundwater salinization in some locations. The strong geochemical fingerprint in the salinized (Cl > 20 mg/L) groundwater sampled from the Alluvium, Catskill, and Lock Haven aquifers suggests possible migration of Marcellus brine through naturally occurring pathways. The occurrences of saline water do not correlate with the location of shale-gas wells and are consistent with reported data before rapid shale-gas development in the region; however, the presence of these fluids suggests conductive pathways and specific geostructural and/or hydrodynamic regimes in northeastern Pennsylvania that are at increased risk for contamination of shallow drinking water resources, particularly by fugitive gases, because of natural hydraulic connections to deeper formations.
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