Januari 09, 2017
it planet earth is a living planet even solid rock and moving as it seemsas an exciting life of its own home but rocks live in geologic time theirlives spend billions of years we humans canbarely glimpsed the living earth inactions 724 victor 430 w box yeah i can you give me an oldfaithful prediction please ok copy thank you itself 120 we're geological wonders through alandscape
the power the birth is most intense you're drawn to these places would make them the centerpieces of ourworld's great parks here on deep connection with planetearth is restoring the rocks we live on make up the birdsuppermost layer its continental crust the in recentyears scientists have been new insight into the nature of theserocks this is their story it is a new story to us but it is reallyis ancient as the earth itself i'll
the continental crust is the part of theearth we walk on it is so familiar that we often take for granted there's crust is intimately linked to the sustainability of all human lifeit's from the earth's crust that we get the mineral resources that we dependupon swells oil resources our water supply islinked to the earth's crust the minerals that plants require two togrow and to feed on on come from the earth's crust and soour ecosystems and all are living matter is dependent on yourscratched but
be worth did not always have a hardcrust on the planet first formed about four and a half billion years ago its surface was a morton see you firethe earth formed as part of the big bang the big explosion resulted in theformation of our solar system mass was strewn out all through spacebegan to accumulate together and probably the initial or was a prettyhot pretty inhospitable place and probably initially fairly homogeneousjust think it is a very hot materialeventually started to cool down
and probably in powders gone are layer cool air for it wasn't until some form aplate tectonics began that we probably begin to build continental crust to get canada across summit this down began to break oftenfall down into the potter in site interior partier thatprobably began to mail as it melted the melt thatcame off was slightly different kinda rock it was probablylighter loaded up to this down to the existingcrust
and born volcanoes but volcanic lava hardened to rock forming the first continental crust good it is now 35 miles thick in places thecontinental crust is much thicker than the crushed under the ocean which is less than nine miles that overall the crust is just a thin film onthe planet making up only one percent of theearth's total side below the crust is the mental which ismade up denser
harder rock that the center of the earthis the core a spear a buyer that is half the totalsize at the plan i'll a real good way to think about theearth's crust i think a real good analogy is dis think about in a and if you thinkabout the shell in the eighties very thin and their relationship to thesize of the egg and inside the egg there's a clear white the eight you canthink about that in a sense like the earth's mantle the second layer down and in the middleof the a guess
is the ok and that's a lot like the yourscore because that's about half the size of the acres in the open in our her score takes about half thesize but the earth's crust is where we live in is that outermost shell and that we derive all that we need for life and to makelife livable civilizations have been built withresources from the earth's crust knowledge about the nature of the crosshas been the keystone today scientists are probing ever deeperinto the mysteries over
this is the katy b drill site in bavariagermany using the largest onshore drill rig inthe world scientists and engineers have drill30,000 feet into the earth's crust it is the second deepest research drillhole in the world after one that measures 40,000 feet inrussia wanna these rock chords come from depp'shave several miles below the surface swim ktb scientists have begun toanalyze them with the most advanced methods roc analysis but they come from a very special partof the earth's crust
here we on old crust in very old contender crust whereusually only drool very shallow holes for what elementearly posits and in this old cross lies the key to theunderstanding of the evolution of the yours the oceansare quite young 200 million years maximum but the the continents up to four point fivebillion years old and in order to understand how the eartheverything came about we we have to look into this the well
into this deep boyd crust and this iswhy we choose this place here we need indirectup and direct place observation and this isall a grill in a very few places scientist can getto engine rocks without the aid of special equipment in the beartooth mountains of montanathe rocks are right at the surface i'll hearing impaired his we have someillness rocks in the world we have remnants approx formed as old asfour billion years ago
in these are mixed with somewhat youngerrocks im magnetic origin than ever range in agesabout 2.8 to 2.75 billion years many of these ancient rocks are made ofgranite granite contains the radioactive elements uranium which decays tulip this allows it to be dated with themachine called a mass spectrometer by measuring these elements in rocksfrom the bear tooth scientists confirm that they were amongthe oldest known rocks on earth i'll the rocks in the bear tooth forfour billion years old
but the earth is 4.5 billion years i v why is the first half billion years atthe group's history missing from the rock record i'll there's a dynamic planet and we have competing processes in the form plate tectonics driving the rock cycleand we can processes at the surface and your thehydrologic cycle and those two cycles conspire to wipeout the early history of the earth and so it's very rare to actually findpieces rock that are
actually soham the beer to serb parliament agentbuilder moms that includes the grand teton ranch in wyoming studies on the rocks in these oldrangers revealed that the face of the earth has changed dramatically over time this is key evidence in support ofgeology is most important theory plate tectonics plate tectonics theory holds that theearth's crust is broken into huge slabs called plates
the face of the earth changes becausethe plates flowed like raps on semi molten rocks below the force that moves the plates is he'dwhich emanates from the very heart of the earth ultimately the energy that goes intodriving the plates around is derived from the interior theearth and it's just a result other radioactivedecay the initial initial elements that wereinvolved in the formation and the nasa became the earth
to understand how he drives the platesscientist simulate the extreme conditions that exist at the center ofthe earth where temperatures reached seventhousand degrees fahrenheit connected the achieve these conditionswith the help of tiny bits of diamyd we can recreate conditions in theearth's core by using a diamond anvil cell we can actually squeeze materialsbetween the tips have to dine angles and we can achieve pressures on theorder of three or four million times the pressure at the earth's surface we can also achieve high temperatures inthe diamond anvil cell by heating with
an infrared laser in because they want to leave herescientists have learned that intense heat from the earth's core and mantle rises up toward the crust this causesthe metal to circulate along the bottom of the crust it is this circulation but movescontinents around and profoundly changes their shape andsize heat circulating deep in the earth cancause the cross to pull apart
all rift they'll in north america a rift sx the homelandat the native problem people in new mexico the global people who lived in the riogrande rift zone for thousands of years they have retained beach in traditionsand many still live in communities called problems the rio grande rift is named after thegreat rio grande river which cuts a deep gorge down the middleof the rift zone the river follows a broad valley in the rift which isflanked on both sides by lofty mountain
ranges this topography is common in rift zones as the earth's crust poles apart itstretches and becomes thinner magma swells up from a mental below causing the cross to bowl choppered andbreak apart broken crossed all blocks rise fall and tilt sideways creating valleysand mountains at the surface what on the cross poles apart formillions of years belizean rangers stretched to thehorizon
this is the case in the basin and rangeprovince of north america after spreading apart for $17 millionyears sections at the basin and range grown wider by one hundred percent thebasin and range bans drying desert country but thespreading bulging crossed has been worked up so high that it invites no during the winter most valleys in the basement rangeprovince are in close by mountains rain and melted snow drain into thesequotations inform lakes like mona lake in california the
on the shores of mono lake stand on rockformations called to for towers tutors are made ofcounseling deposited by underwater springs thetowers were one summer but siphoning of lake water for humanuse has left the two firs high and dry the presence of calcium rich bringsreveals another feature of crustal spreading volcanic activity when there's rifting there's typically a break in the crestat the crest itself has broken apart and prior to breaking apart it stretchesthen
stands and so as multi materials maketheir way up it's very easy for him to get throughthe crust and as they come through the crust wesee them as well k nelson in the past member volcanic eruptions have blanketed therift zones of north america with the players have lava and ash now hardened to colourful rock book and a crock was a building materialfor the engine problem people at the rio
grande grid in some places clips a volcanic rockform the back wall of dwellings a volcanic rock called carports often of the cave dwellerscould carve into it with simple hand tools if crustal spreading persist it can split a comment in half ocean waters move in this happened inafrica where the famous african rift opened agap between the compliment and saudi arabia
the red sea was born in north america the rio grande rift and basin and rangeprovince may or may not progressed to the ocean stage but the crust is spreading apart today creating a lively rugged landscape oneof the liveliest places associated with crustal spreading lies just north of thebasement range problems at a place called yellowstone but yellowstone national park is worldfamous for its bizarre volcanic
landscape on there are no active volcanoes heretoday but pastor options are among the largest ever produced on earth below yellowstone a column apart magma rises from themetal to within a few miles above the earth's surface the subterranean magma fuels hundreds ofgeysers in the park up thousands of other thermal featuresare found here in fact yellowstone park contains thegreatest concentration of magma driven
features in the world at any time magnum a once again rise tothe surface at yellowstone geysers will be replaced by volcanoesand memnoch the russians have lava and ash pastor options at yellowstone havethickened the group crossed with thousands of feet a volcanic ash inblood the entire dept at the colorful yellowstone river canyon has made avolcanic rocks where lava flows pile up in the canyon the river cascades 102 feet overwaterfalls
yellowstone dramatically shows allbalkan -ism thickens the car metal cross to the surface recently geologist to discover thebakken -ism also thickens the crushed in a different way from the bottom down up some well this is the cmo ball canning field apart of the basin and range province in california's mojave desert i'll i'll
here geologist comb the flights haveseen as dormant volcanoes looking for special rocks calledzealand's i'll very special localities like the cementvolcanic field have great permanent journalists tens of thousands so very importantlocalities you try to piece together what happeneda firm and lower crust i'll words and laugh the roots in the words analyst theindicate foreign rock fragments and the remains for and &lifshitz rock
the sir rocks that do not belong to the to the lab for thatbrought them to the surface single its were once part of the bottomof the earth's crust and even part of the metal they formedthe deep inter-lining a volcanic condoms on volcanoes come to life rising magmarips chunks of rock from aligning and carriesthem to the surface when you see the law at the circus you'll notice different looking rocksand
maybe white little white and black rocksthat come from deep in crest or those fascinating little green beauties little granular green clusterswhich are pieces in the mantle z looks are important because they giveus a direct look at the bottom side of the com- with the help of machines like theelectron microprobe single its reveal a fascinating newpicture at the bottom of the earth's crust home the traditional series called
the crust ends abruptly were and meetsthe denser rocks at the mantle disney sharp boundaries nickname the mobile and but seen a live show that the model wasa bit messier involved canuck regions but magma from the metal often rises to thebottom of the cross but then goes no further the mobile is obscured scientistsrecently learned that this was the start of an important process of crustalthickening
called underplaying underplaying us aprocess by which magma that's generated in the arsemantle is and into the earth's crust but at the base of the crust normally wethink i've magma as rising on way through the crust and coming out at the surface andvolcanoes but when underplaying and sediment making itall the way to the surface actually stops and ponds right at thebase of the crust work contact the upper mantle eventually
the magma from the metal hardens to rockand becomes new continental crust in this way under plating makes thecrust grow thicker from the bottom down it turns out that under plating is addednew cross to the bottom apartment all over the place here in the alps havenorthern italy geologists can actually see where thishappen billions of years ago this is the you bring your bottles of arug place where geologist must also be expert rock climbs be a bruise on his near the boundarywhere to crustal plates me
the european and african plains in millions have years ago italy a part of the african plate was anisland in the ancient mediterranean sea the african plate then move northcausing italy did dock with the carton of in during the collision rocks in the ancient sea floor hadnowhere to go but up now rise more than 12,000 feet above sealevel don't mind ranger northern italy
geologist once thought that the entirethickness of the cross grows out of the ground here exposing the mall the ab ripper panelson was a place with the mall could be /c the ball was thought to beso shop online that one could put a finger on it appeared that crushed rocks were onone side mantle rocks on the other but the moregeologist study the area the less that's the reason true your so malval including
he began to look as though all the rockshere were crustal rocks perhaps this was one of those placeswhere metal rocks have been transformed in the crustal rocks by underplaying to find out for sure geologist tookhundreds rock samples back to the lab for analysis okay man i think we're ready for thepressure vessel her in lab experiments the umbria rocks were subjected to theextreme conditions that exist at the bottom of the earth's crust
temperatures down their reach 1200degrees fahrenheit and pressures are 10,000 times greater that the serbs yep best with you these experiments confirmthat underplaying did indeed take place at the ab ripperbottles own scientists have also learned that under pleading and other processeshappening in the lower crust can have major effects at the earth'ssurface but we know that there's lots of things that go on down the lower crust that the earthand many of these things have a profound
influence on us as humans and surface at their rocksand minerals change when when they're subjected toheat and pressure rocks can melt the minerals in the rockscan in i change themselves into into dancerminerals and so the rocks themselves become heavier and all these things manifest themselveson the surface of the yr rocks melting give rise to magnitudereplicated in explosive volcanism minerals and rocks can dehydrate giving
rise to water and co2 which are implicated in formation gold andsilver copper deposits all of these processes which have their origins deepin the crust have manifest themselves on the surfaceof the earth in ways that are very important to our survival as humanbeings or to the longevity of our civilizations in the san francisco bay area the crustmantle boundary plays a ruled in a destructive scenario
all the loma prieta earthquake up 1989 damage was heavy in and around sanfrancisco but the quakes at the center was more than sixty milesaway in between relatively minor damage occurred up it turns out that loose soils were afactor in the severity of ground shaking in san francisco but scientists think there may have beenanother factor some seismic waves generated during thequake went down struck the mojo at an angleand then bounced back under sent
francisco apparently these bouncing waves weremore destructive than waves traveling straight through the earth's crust a large quake is predicted to strike theheavily populated east side of san francisco bay whichlies above the hayward fault because so many people are at risk earthquake scientist conducted anexperiment to predict what might happen when that quick finally strikes from the1989 loma prieta earthquake we noticed that indeedseismic energy does
go down strike mojo and come back andany them system we wanted to see here in the eastbay along the hayward fault if a similar type none would occur and that since we can't wait for thenext earthquake one other thing so there's one outgenerated around we but explosive sources in highprobability areas areas we know are very likely to generate alarge earthquake in the near future and we wanted to see how the energy withtravel from those locations to north inberkeley
oakland and at the populated areas andalso to the south and the san jose area 7 6 for for 3 to 1 from the sunday with people would have aa large earthquake sign energy from that earthquake with traveldown strike the mojo and surface underneaththe oakland berkeley area i'm and from our indications this then shaking would be very intense muchmore so
then was observed from the 1989 lomaprieta earthquake coming on the san up to scientist earthquakes are a sourceof valuable information when a big quake occurs anywhere onearth scientist get a glimpse at the entire inner structure of the planet but mostof what we know about the earth's deep interior has beenderived from studies a birth weights summer the deeper search quakes occurquite deep 700 kilometers deep and waves just like throwing a rock intoa pond water they the earthquakes release energy createwaves these ways travel
all the way through the year through thecenter the earth their recording on the other side of the world and by studying these waves havetraveled this is the job the seismologists turning them around theworld we've learned that the interior this layered it's not just one singlehomogeneous mass but its comprise a player's at different compositions am in while earthquake reveal a rough picture of theplanet's interior scientists often need
more detailed information about theearth's crust one other methods of getting it isthrough aeromagnetic surveys up the instruments in thespecially-designed plane detects the magnetic fields in crustal rocks cautions decade reviews ok many rocks in the cross contain magneticminerals such as magnet to
by analyzing the magnetic variation tothese rocks scientists can detect unseen geologicfeatures very deep in the earth's crust them the plane flies low and slow over theterrain to collect data and i'm recently an aeromagnetic survey was flown overnorth america's west coast the objective to explore the differencesbetween continental and oceanic crust as flight lines have data are piecedtogether on a map
an incredibly complex picture of theearth's crust on full slow yet there is no heed to this complexityin the subdued to rain around seattle washington a major west coast city it is only through magnetic surveys and other geologic studies that thestartling subterranean seen beneath the west coast israel the to crustal plates overlap each other below seattle oneplate makes up the ocean floor
and where it meets the continent itbends and dives underneath it this is called a subduction zone sometimes the two plates lurched towardeach other unleashing the tremendous job at the surface on it good friday 1964 on north america's strongest quake onrecord struck near anchorage alaska leveling the seaside city so tremendouswas the shock but it was felt in florida
some 5,000 miles away the alaska quakewas a subduction zone earthquake we need the mountainous terrain aroundanchorage the group is restless here the pacific ocean floor subductingbelow the calm the most powerful earthquakes on herthird triggered by subduction of the earth's crust a subduction zone runs along northamerica's west coast from alaska along the coast of canadaall the way to keep them in the scene when california subduction scopes a beautiful ruggedcoastline when it occurs at the commons
age this is because over time the subductingplate grinds forcefully on the plate above as it slides underneath the topleadership upward in response of mountain ranges are built along thecoast like the olympic range in washington after millions of years the subductingplate sinks deep into the hot metal where it begins to melt magma forms andsometimes rises through ruptures in the
plant a bomb this creates another powerful forcecaused by subduction saint helens in washington erupted meetyou 1980 subduction triggered the eruption whichdevastated the landscape for miles in all directions i'm i'm a dense forest was blown over bythe blast and buried under pick players a volcanicash mount saint helens is one of many powerful volcanoes that were built bysubduction along north america's west coast
majestic mount rainier stands 50 milesfrom seattle up mark baker washington rises near theus-canadian border to the south crater lake an organ was ahuge volcanic peak before an eruption blew its top of seven thousand years ago way many times in the geologic past thesevolcanoes have erupted far more powerfully than mount saint helens as long as subduction drives the crustal plates below besleeping giants will surely awaken again
and again the granite domes the assembly nationalpark in california mimic the shape of the volcanic peaks inthe pacific northwest subduction created both but the domesabusive a deformed in a different way granite is a rock that owes itsexistence to subduction it forms when a subducting plate meltsand magma rises up through the overlying plight but the magma often fails to makeit to the surface and a volcanic eruption instead it cools and hardens deep withinthe crust
forming granite this is called a granite batholith well this is the process that form yourseventies granted we see these rocks today because a roachin strip thousands of feet of birth of the top of the sierra nevadabatholith another granite batholith was exposed byerosion in the state a vital but geologist working in the area werepuzzled to find rocks that were formed by subduction subduction generally occurs at the
educomp but these rocks are 350 milesaway from the nearest coastline to the west how to the end up so far inland clues came from the rugged hell's canyonarea just to the west to be idaho batholith on the banks of the snake river geologist found huge piles a volcanicrocks called pillow lavas these rocks formed where molten lavapoured into the ocean but
pillow lavas are forming today on theisland of hawaii lover is arriving from a small tent onthe volcano killer whale from this fiery cauldron mall thinkershave lava flowing underground tunnels to the pacific ocean shoreline world underwater the lava seems to be fightingto stay mold but it cools quickly hardening into pillow shape rock way well when they found the same kinds rocks andhell's canyon geologist at a problem
a crucial ingredient in the rocksformation the ocean was missing these rock scene wildly outof place 1 for their work in hells canyon you wouldmore rocks that had formed in the ocean these rocks are really rich in the maybe a possible there thing on that onehere's another one fossil so creatures that live ontropical coral reefs were found alongside the volcanic rocks measure
coral reefs only formed near the equatorbut hells canyon is thousands of miles north at the acquitted geologist for now certain that the rocksand hell's canyon were formed in a far-off exotic location at that time the landscape look much different thanit does now in fact we think that there were probably chains or chains islands out in the northasian-pacific we don't even know exactly where theywere but
so different than what we see today inhells canyon and you can probably think about a a stringer violins maybe 20 or 30 a.m.out in the ocean maybe for several hundred miles some ofwhich had bought enough once in a while gold box deals with iraqand when they erupted the more power on through things in the air probably 8 10 twenty miles on funny blot out thesun for a while they were so explosive but the debris that we see from thosevolcanoes
are mostly what i've been happy on in hells canyon for the injured hell'scanyon islands to move from the tropics all the way to their present location inido there must have been profound movements of the earth's crust or plates and about $130 million years ago the westcoast of north america was located in western idaho and the volcanic islands of hells canyonwe're a group of islands offshore the mainland a subduction zoneexisted along the coast
as the ocean played subducted below thecomment the injured islands which were attached to the moving plate moved closer and closer to the coast the finally the island's collided with thecompound when the island's joined the common ittook a long time it may have taken a hundred millionyears for the process to occur a small and if we livewe wouldn't even know is occurring and even during the time the dinosaursprobably about as long as the dinosaurs
lived is how long it took for these islands to joined to northamerica subduction has been active ever sincebringing in more islands and parts of the sea floor the the west coast north america grew larger bit by bitthese new pieces of continental crust recalled exotic touring well in alaska at the edge of the originalcontinental landmasses
sits mountain ali north america'shighest null to the south and west all the land isexotic added to the comment by subduction it anchorage is built on the chugachstirring a beautiful exotic land that was once part of the ocean floor farther south along the canadian girls ahuge island will become a new exotic terrain of north america subduction is pushing vancouver islandcloser and closer to the mainland and eventually they will collidevancouver island might be renamed
the vancouver peninsula my scientists now believe that much ofwestern north america is exotic in general most herbal and west to theamerican and canadian rocky mountains is made a big xotic continental crustthe rockies themselves were created when subduction first began millions of years ago atthat time the comment ended here and it had a relatively flat coastlinebut when the oceanic plate began to dive below the comment coastal lands were shocked upward tocreate this majestic
range of martin's ok western north america is perhaps theworld's best example of a common pieced together by tectonic forcessubduction rifting and under plating all played apart in this drama love continental group the and wat tectonic forces create thecontinental crust where the cross shows itself for the service a difference in a forces around theworld scolding
carving and even destroying thistectonic handiwork what these are the fortunes overruled the boulders erosional artist is water it works onthe cross to the former waterfalls rivers and rainy wanna be europe's most dramatic watersculpted to rains is found in the southwestern united states and good
head this is bryce canyon in southern utah it is part of the colorado plateau agreat blog the earth's crust that was parchedupward by plate tectonic forces water carve this very lansing in thesoft red rocks albright's in some areas of the colorado plateau running water cuts deep canyons throughsolids and stop at canyon de chez geology students get apowerful lesson in the processes have canyon formation
this land here was all horizontal but their streams runningthrough it and there is cholera uplift the coloradoplateau and when this up what is happening thisyear is still running through creating this came to say so we can do so here today in mystic quite on time million two years in as students explore the geology ofcanyon the shi'a they discover something unusual in thecliffs above
centuries ago native american peoplebuilt their dwellings in the knock some sense dawn clips marched caves a carved out by thecombined forces of surface water and groundwater 0 well cool the grandparent all canyons is thegrand canyon in arizona cool it is almost too much to believe thatthis mile-deep spectacle was sculpted by water but in geologic time
the years are many the colorado riverhas worked with al rest through the ages some when water freezes to weis anotherpowerful larosa forces created glaciers got the earth's surface with astronger hand and flowing water i'll glaciers covered vast parts of theearth during the ice ages which ended about 10,000 years ago up when they retreated they left thedistinctive mark on the landscape i'll know where is the signature %uhglaciers so striking as a new assembly
national park yosemite valley gets its movie you shape profile from the action of glaciers up you thousands of years ago glacier filled the entire valley up eventually the glacier retreatedrevealing the bold and the workers movie nights well up when the glaciers retreated fromyosemite at the close of the last ice
their melting ice field deep pockets onthe ground to form beautiful alpine lakes good the clips mirrored in their waters seemas permanent as the sky above but that was just an illusion for this gentle substance called waterwill reduce these rocky cathedrals to nothing flatness is the goal erosion 0 were plate tectonic forces to suddenlystop building mountains water erosion would reduce the land to alevel playing
0 only sand dunes rise above the plane's piled up by the blowing winds and there is another force that is greatlymodifying the earth's surface the group human population is increasing at alarming rates andwithin are huge appetite for resources from the group crossed are we damaging the cross beyond repair if you if we damage the crust there arelotsa back to geologic processes that can undo the damage i think the criticalissue is
are we extracting resources from thecrust sustainable rate the answer to that is of course is no we're not we're extractingresources at a much greater rate than they can possibly be replenished and this gets back to theissue love love the geologic versus human timescales we perceive the earth is being here forever as on human timescaleand yet the geologic processes that are required to replenish resources that were using a very rapid arare very rapid pace
a require millions and millions andmillions of years so we are in fact damaging the crust ofthe earth and in ways that it relates to thesustainability of our civilizations and and us as a humankind world you may very well deplete the resourcesthat the crust is provided we may even abuse the earth's crust inways that lead to our own extinction on but the process is that regeneratethe crust originate many miles below the surfaceit is unlikely that humans will be able
to influence those processes good plate tectonics will carry on i new continental crust will be created atsubduction zone offshore islands will be welded on twocontinents to become exotic terrain comments will be split and stretch wideralong with so europe will live on forever changing theexpressive features
a bit rocky face me well good well all bring said day thing
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