Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 


Forgot your password?
Close
typodupeerror
×
News Science

2.5 Mile Deep Hole Drilled Into San Andreas Fault 204

Posted by CowboyNeal from the heart-of-the-matter dept.
iandoh writes "Cool research: Geologists at Stanford University and the US Geological Survey have drilled a 2.5 mile deep borehole into the San Andreas fault. They've extracted over one ton of rock from 2 miles down, and they'll be installing sensors down the length of the borehole."
This discussion has been archived. No new comments can be posted.

2.5 Mile Deep Hole Drilled Into San Andreas Fault More

2.5 Mile Deep Hole Drilled Into San Andreas Fault

Comments Filter:

  • Lex Luthor is Pleased (Score:5, Funny)

    by hedgemage ( 934558 ) on Thursday October 04, 2007 @08:45PM (#20861753)
    Oh, sure, just do his work for him. Why not install some nuclear warheads down there while you're at it.

  • Only 2.5 miles? (Score:4, Insightful)

    by Harmonious Botch ( 921977 ) * on Thursday October 04, 2007 @08:47PM (#20861771) Homepage Journal
    The fault is between the Pacific Plate and the North American Plate, both of which IIRC are more than 50 miles thick. Why are we looking at only the upper 5%? ( Modern oil wells are drilled as deep as 6 miles or more now. )

    • Re:Only 2.5 miles? (Score:5, Insightful)

      by Protonk ( 599901 ) on Thursday October 04, 2007 @08:57PM (#20861877) Homepage
      Seems deeper than the average depth [doe.gov] of most oil and gas wells. Were you thinking of the depth of wells on the ocean floor from sea level?

      It does seem to be less than the record [findarticles.com] there. But we can hardly fualt (har har) the team for not digging the full 50 miles to the asthenosphere. :)

      • Re:Only 2.5 miles? (Score:5, Informative)

        by Harmonious Botch ( 921977 ) * on Thursday October 04, 2007 @09:45PM (#20862311) Homepage Journal
        A quick google revealed the following:

        The deepest oil well penetrates a mere six miles (ten kilometers) into the crust (the center of the Earth is about 4,000 miles [6,000 kilometers] deeper). Russian scientists dug the deepest hole on the planet in Siberia, but bottomed out at about 7.5 miles (12 kilometers) below the surface. The Mohole project, a 1950s-era U.S. plan, called for drilling a hole 25 miles (40 kilometers) down to the Mohorovicic discontinuity, the boundary between the hard rocks of the crust and the gooey mantle. Sadly, the only discontinuity Mohole ever encountered involved government funding.
        It gets harder and harder to drill deep into the Earth because rocks get softer and softer. Brittle at the surface, rocks become plastic at depth, and the pressure caused by the weight of the overlaying crust--about 52,800 pounds per square inch (3,700 kilograms per square centimeter) at a depth of ten miles (16 kilometers), says drilling consultant William Maurer--collapses deep wells, making further drilling impossible.
        • Wait, wait... they "bottomed out" at 7.5 miles? Somebody's not telling us something. Did they hit the table on which the earth sits? Or perhaps the impervious shell of a turtle?

          • Re:Only 2.5 miles? (Score:5, Informative)

            by ShatteredArm ( 1123533 ) on Friday October 05, 2007 @12:22AM (#20863641)
            Actually, their drill began melting. Heat is the biggest obstacle to drilling further than 7 or 8 miles into the earth.
            • That depends very much where you drill I suppose. A rough estimate would be that if the crust is twice as thick, temperature will rise half as fast.
              I seem to recall that oil wells are only found far away from fault lines (it would be nice to know for sure).
              • Well, for comparison, the Kora Borehole [wikipedia.org], which is the deepest achieved at 7.6 miles, was done at a point where the crust is estimated to be 22 miles thick.

              • Re: (Score:2)

                by jbengt ( 874751 )
                "I seem to recall that oil wells are only found far away from fault lines"

                Oil wells are found wherever someone drills them.
                But if you drill one near a fault, the oil will be long gone
                Oil's a liquid, it will flow out along the cracks.
                Oil and gas is usually found under layer of impervious rock shaped like an upside down bowl.
                That's what they look for in the seismographs.

          • Re: (Score:2)

            by donaldm ( 919619 )
            No they did not find any turtle shell, however I have it on good authority that they found some leathery grey substance but some guy's flashing UU badges came and took it. It's funny though no one saw what vehicle they came in.
          • But what if they drilled right through the unfortunate testudinate?

          • Re: (Score:2)

            by Goaway ( 82658 )
            No, it's well known that they stopped because they reached hell [vasa.abo.fi].
          • They struck the river Styx.

    • Re:Only 2.5 miles? (Score:5, Interesting)

      by tyrione ( 134248 ) on Thursday October 04, 2007 @08:58PM (#20861885) Homepage

      Modern oil rigs don't drill into one of the world's largest fault lines. This depth will give a very broad understanding, topologically the distribution of vibration analysis, fracture mechanics, etc., etc.

      Models will be developed to study and help with how the Earth expands and contracts.

      • Re: (Score:3, Interesting)

        by UbuntuDupe ( 970646 )
        Heh, if an oil company *did* dig this deep into the San Andreas Fault, I'm *sure* they would be applauded for the scientific discovery they've facilitated...
      • While this is possibly true, the real purpose of the drilling is not understanding, but prevention of earthquakes.

        Over five tons of sheep's bladders are going to be dumped directly into the hole. It is the firm belief of Arthur and all of his brave knights (and also Sir Robin), that this allow many more years of peace within this land...at least, as soon as the duck-weight based justice system is instituded.
        • This new learning intrigues me. Explain to me again how sheep's bladders can be employed to prevent earthquakes.
    • We aren't drilling 6 miles into the fault because any oil that might have been in there would have already oozed out onto the surface.

    • Re: (Score:2, Interesting)

      by skelly33 ( 891182 )
      Last summer I took a guided tour down into a hard-rock mine shaft several miles deep here in California. One of the questions that was asked was what happens if there is an earthquake and people are in the mine. The answer surprised me: they can't feel earthquakes down there, so the effect is nil.

      Apparently, we were told, the destructive force of earthquakes is carried along the upper couple hundred feet of the surface. I am reminded of a body of water that has waves and turmoil on the surface but which i

      • Re:Only 2.5 miles? (Score:5, Interesting)

        by Harmonious Botch ( 921977 ) * on Thursday October 04, 2007 @11:09PM (#20863037) Homepage Journal
        I suspect that they were lying to you to prevent panic. Mines are a favored place to study earthquakes. Indeed, being in a mine probably gets you closer to the epicenter, as most eathquakes are centered miles below ground.

        from iopd.og:

        Hundreds to thousands of small to moderate earthquakes per day are recorded in a typical deep mine; the strongest may reach an intensity of magnitude 5. Given that many of these earthquakes are controlled directly by the mining activity, their location, timing, and magnitude can be forecast, and instruments can be installed at sites where earthquakes of interest are predicted to occur. The mine infrastructure provides access to the earthquakes' source region and allows three-dimensional mapping of the fault zone. It also allows installation of a three-dimensional array of instruments 1-100 m from an anticipated hypocenter to monitor fault activity before, during, and after an earthquake. Most expected earthquakes exhibit a moment-magnitude range (-2 to 4) that bridges the scale gap between laboratory experiments and tectonic earthquakes in the crust. The mine infrastructure provides an opportunity to investigate the effects of fracturing during earthquakes on fault fluid, gas chemistry, and microbiological communities. These promising conditions have led to the building of an earthquake laboratory in the TauTona gold mine in January 2005 as part of the DAFSAM-NELSAM project
        From the Southern California Earthquake Center:

        Northridge earthquake had a hypocentral depth of 18 kilometers (11 miles), deep for a California earthquake, but considered shallow compared to other regions.
        ( In California even the earthquakes are shallow. )

        An interesting map is at http://seismo.berkeley.edu/istat/ex_depth_plot/ [berkeley.edu]

        • Re:Only 2.5 miles? (Score:4, Informative)

          by E++99 ( 880734 ) on Friday October 05, 2007 @12:16AM (#20863605) Homepage

          I suspect that they were lying to you to prevent panic. Mines are a favored place to study earthquakes. Indeed, being in a mine probably gets you closer to the epicenter, as most eathquakes are centered miles below ground.

          Yes, being a couple km down gets you probably closer to the epicenter. But since the weight pressure on the rock increases linearly with depth, it is reasonable to think that the movement in earthquakes decreases linearly with depth, until it reaches whatever movement was at the epicenter.

          Imagine if you took a large compression spring, held it vertically from the bottom, placing a rock on top. Any sudden movement you make with your hand (the epicenter), will result in an amplified oscillation of the rock (the surface), with linearly smaller movements along the spring. IANA earthquakeologist, but it seems to me like an roughly appropriate model.

          • Re: (Score:2)

            by mike2R ( 721965 )
            However, even if the main mine workings are deep enough to avoid damage, it does seem likely that the entrances and ventilation could be destroyed.
        • Indeed, being in a mine probably gets you closer to the epicenter,

          Don't hardly neither. The epicenter is on the surface by definition.

          RYOFP: Northridge earthquake had a hypocentral depth of 18 kilometers

          Hypocenter is the word you want.

          rj

        • Surface Waves [mtu.edu]


          Travelling only through the crust, surface waves are of a lower frequency than body waves, and are easily distinguished on a seismogram as a result. Though they arrive after body waves, it is surface waves that are almost enitrely responsible for the damage and destruction associated with earthquakes. This damage and the strength of the surface waves are reduced in deeper earthquakes.

        • Re: (Score:2)

          by syrinje ( 781614 )
          Being underground gets you closer to the "Focus" of the earthquake - the epi-center is the point on the Earth surface directly above the focus. If the mine is in the liquefaction zone - you can put your head between your knees and kiss yourself goodbye. Yes, they were lying to you. On the other hand, a smaller hole deep underground might actually facilitate survival, and come out unscathed much like a bubble in a votex. YMMW :)
      • The answer surprised me: they can't feel earthquakes down there, so the effect is nil.

        As someone who has experienced a relatively minor tremor while underground, I can tell you the effect is definitely not nil

        In my case, it almost resulted in needing a change of trousers.

    • Re:Only 2.5 miles? (Score:5, Funny)

      by doktorjayd ( 469473 ) on Thursday October 04, 2007 @11:00PM (#20862963) Homepage Journal
      Modern oil wells are drilled as deep as 6 miles or more now.

      heh,

      and modern measures are in metric.
    • Drilling cost go up as square of depth. Oil companies can afford spend a hundred million to drill five miles below two miles of water. The NSF cannot afford really deep holes. The entire NSF earth science budget is lees than the average oil company single deep water hole.

  • Don't let them fool you! (Score:4, Funny)

    by Black Parrot ( 19622 ) on Thursday October 04, 2007 @08:47PM (#20861775)
    It's probably the CIA trying to recover a lost Soviet rock diver.
  • Let me tell you something. After digging that hole I am ready for a six-pack. And I wish they would have thrown in a pair of gloves, cuz I gots some serious blisters.

  • faulty logic. (Score:5, Funny)

    by User 956 ( 568564 ) on Thursday October 04, 2007 @08:56PM (#20861863) Homepage
    They've extracted over one ton of rock from 2 miles down, and they'll be installing sensors down the length of the borehole.

    I wouldn't want to be the guy who's in charge of monitoring sensory data from something called "the bore hole". that sounds like a really tedious job.
    • I wouldn't want to be the guy who's in charge of monitoring sensory data from something called "the bore hole". that sounds like a really tedious job.

      Better that than "the boar hole" ... those things can be really dangerous when you piss them off.

    • Re: (Score:2)

      by tkw954 ( 709413 )
      I remember seeing a section heading in a British Yellow Pages:

      Boring: See Civil Engineers

  • About time (Score:5, Funny)

    by Xeth ( 614132 ) on Thursday October 04, 2007 @08:59PM (#20861897) Journal
    I feel our economy will be well served by the extra 6 energy.
    • Damn, beat me to it. I'll spare y'all the obligatory joke about mindworm attacks.
    • Energy? You build the boreholes for the MINERALS, the energy is just a side benefit!
      • We require more vespene gas, not minerals or energy, dammit!

      • Re: (Score:2)

        by Xeth ( 614132 )
        Yeah, but I figured that didn't have the same contemporary "pop"; The U.S. seems to have more of an energy problem than a mineral problem (it's my understanding that soaring metals prices are just a side-effect of an all-around plummeting dollar).
  • They should dump a few tons of super glue down there. That'll fix her.

  • talc as a lubricant (Score:5, Insightful)

    by khallow ( 566160 ) on Thursday October 04, 2007 @09:08PM (#20861957)

    They drilled in a part of the San Andreas fault that creeps and doesn't generate big earthquakes. My take is that they're looking for a lubricant, something that allows the fault to slide. Another possibility would be merely that the fault doesn't have bends or splits in it unlike the faulting at the south end of the San Francisco Bay. The San Andreas fault runs along a chain of mountains south of Silicon Valley and then north through San Francisco, following the coast thereafter, while the Haywood fault runs along the base of mountains east of the Bay area from Milpitas to north of Oakland.

    If a lubricant is responsible for the fault creep, there are apparently several possibilities: water, serpentine [wikipedia.org] (which can be formed by weathering or metamorphization of several minerals including olivene/peridot), or talc (formed by serpentine exposed to water). If you have talc, you probably have the other two as well. Serpentine is a bit harder than talc (the latter is soft enough to easily scratch with a fingernail), but both deform easily under pressure. I seem to recall cases where serpentine has "bubbled up" over millions of years through denser rock, acting as a very slow moving fluid.

    As I see it, if we can understand how to lubricate faults, then it is possible to not just trigger faults, but also to ease pressure on a fault. Maybe the cost of the materials will make it infeasible, but we can consider it now.

    • Re:talc as a lubricant (Score:5, Funny)

      by dustwun ( 662589 ) on Thursday October 04, 2007 @09:17PM (#20862069) Homepage
      Does a reply to this involving 'Lubing the bore hole" get modded as funny, or troll?.. you be the judge....

    • Re: (Score:3, Insightful)

      by dodongo ( 412749 )

      while the Haywood fault runs along the base of mountains east of the Bay area from Milpitas to north of Oakland

      It's called the Hayward fault, and it experiences plenty of creep all along the East Bay. The last quake greater than 4 that happened on it was basically across the street from my apartment. Trust, it's moving, and generally nonviolently (though noticeably at times). In fact, it runs through the middle of Memorial Stadium [wikipedia.org] in Berkeley, which is built in two halves that have crept about a foot and

      • Re: (Score:2)

        by dodongo ( 412749 )
        I should note that while it is creeping, it's also the strongest candidate for major quakeage based on many recent San Francisco doomesday predictions.

        • Re: (Score:2)

          by khallow ( 566160 )
          IIRC, the problem is that most of the fault doesn't creep, but is locked. I think the part you refer to near Berkeley is between two locked segments. One of the worst case scenarios is that both segments go at the same time.

      • Re: (Score:2)

        by E++99 ( 880734 )

        In fact, it runs through the middle of Memorial Stadium in Berkeley, which is built in two halves that have crept about a foot and a half offset since the stadium's construction.

        Talk about home field advantage! "Upon further review, the 10-yard-line is now 11 yards from the goal line, and the first down is voided. Bears' ball!"
  • Can someone please explain how to unlock this feature ? Is it similar to the Hot Coffee mod ? Where can I download it ? I've been playing San Andreas for years but have never encountered any kind of drilling mission or mod.

  • Dear God, No! (Score:3, Funny)

    by cmcguffin ( 156798 ) on Thursday October 04, 2007 @09:22PM (#20862115)
    Keep the Mole Men down there where they belong!

  • 2.5 miles down? (Score:3, Funny)

    by jollyreaper ( 513215 ) on Thursday October 04, 2007 @09:56PM (#20862403)
    No, thank you. I'm not checking there for a hidden package.

  • Silica Gel reducing friction in fault zones? (Score:4, Interesting)

    by Diamonddavej ( 851495 ) on Thursday October 04, 2007 @09:57PM (#20862413)
    My favored culprit for drastic friction reduction during faulting is lubricating Silica Gel; finely crushed quartz in the active fault zone reacts with water forming fluidic silica gel. There is excellent laboratory evidence of silica gel lubrication in simulated fault zones (see Mineral Gel May Reduce Rock Friction to Zero During Earthquakes, http://www.nsf.gov/news/news_summ.jsp?cntn_id=100325 [nsf.gov]. All that is needed is field evidence, and I think I have it.

    • Re: (Score:2)

      by Speare ( 84249 )

      My favored culprit for drastic friction reduction during faulting is lubricating Silica Gel; finely crushed quartz in the active fault zone reacts with water forming fluidic silica gel.
      And I have it on good authority that it's best to spray highways with huge vats of chicken fat and banana peels just before rush hour...

    • My favored culprit for drastic friction reduction during faulting is lubricating Silica Gel;
      Just make sure you don't eat it!
    • Y'all are wimps. Here in Colorado we used to produce earthquakes by lubricating old faults with chemical WMD's including nerve gas [nyx.net] because everyone knows the best thing to do with nerve gas is pump it into a hole just outside of an enormous city.

      Some friends of mine had a gold mine that kept collapsing -- they got most of their gold from a slip area at a fault line, and that's what was moving. The snag was: why were the earthquakes happening once a month, on Saturday morning? People started asking questi
    • Astroglide http://www.astroglide.com/ [astroglide.com]
      WD-40 http://www.wd40.com/ [wd40.com]
      Wet http://www.stayswetlonger.com/ [stayswetlonger.com]
  • All adjacent areas are reporting increased energy and mineral production. Peculiar worms have also been reported in the area.

  • Brilliant (Score:3, Funny)

    by Whiteox ( 919863 ) on Friday October 05, 2007 @04:34AM (#20865079) Journal
    Idiots!
    What a dumb move.
    Geophysicist Nerd 1: "Hey let's drill a hole 2.5 miles into a known fault!"
    Geophysicist Nerd 2: "OK! Let's do it."
    drill drill drill drill drill drill drill drill drill drill drill drill drill drill drill drill
    Nerd 2: "Now what?"
    Nerd 1: "Ummm... How about we put some sensors down there?"
    Nerd 2: "Hey! Why not!!!"
    Nerd 1: "Errmmm... Shit! We've only got 1000ft of wire!"
    Nerd 2: "Damn!"
    .
    .
    "Hey! What's that really hot red stuff bubbling out of the hole?"
  • "Borehole", isn't that a slang word for a jerk who hogs a meeting?
  • Did Stanford just buy up some real estate in Nevada?

Slashdot Top Deals

A committee takes root and grows, it flowers, wilts and dies, scattering the seed from which other committees will bloom. -- Parkinson

Close