Monster worm and sea star frenzy December 2, 2009 Monster worm and sea star frenzy Deep under the Antarctic ice, a rare, colourful burst of starfish and 3m-long monster worms has been filmed by a BBC camera crew. Filmed in time-lapse, the extraordinary swarm of deep-sea creatures gathers to feed in a frenzy on the body of a seal, which had sunk to the ocean floor. Such a bounty of food may only occur once every ten years in the ice-cold waters of McMurdo Sound, Antarctica. The images were taken by divers filming for the natural history series Life. The time-lapse sequence revealed the feeding frenzy of hundreds of huge worms, starfish, brittle stars and sea-urchins. Reading Ch. 14 Final Exam date: TU, Dec. 15 Material covered: Ch. 13, 14, 15, 16
Recap Eastern margin Southern margin Interior Western margin Rifting, lava expulsion EX: The Palisades (NY-NJ) Southern margin Depositional basin, evaporites Gulf of Mexico Interior Erosion and deposition Navajo Sandstone (Zion NP) Western margin Undergoing compression Picking up exotic terranes http://ca.water.usgs.gov/groundwater/gwatlas/summary/geology.html http://homepage.ufp.pt/biblioteca/GlossarySaltTectonics/Pages/PageS.html http://www.planetware.com/picture/new-york-state-hudson-river-valley-us-ny156.htm
Sonoma Orogeny Island arc collision Forearc basin (Great Valley Grp) Volcanic & ocean sediments Accretionary prism (Fransciscan Cx) blueschists Foreland basin (Morrison Fmn) Volcanic & terrestrial sediments Picture of folded blueschists in CA http://www.geol.umd.edu/~tholtz/G102/102meso1.htm http://www.es.ucsc.edu/~afisher/Courses/Eart205/GradSeminarPhotos.html
Cordilleran Orogeny 1st phase: Nevadan orogeny Granitic magma intrusions Ex: Sierra Nevadas Ex: Idaho batholith http://www.eugenecarsey.com/camp/alabamahills/arches2.htm http://higheredbcs.wiley.com/legacy/college/levin/0471697435/chap_tut/chaps/chapter15-04.html
Cordilleran Orogeny 2nd phase: Sevier orogeny Low angle thrusts Spring Mtns, NV 2nd phase: Sevier orogeny Low angle thrusts Sevier thrust belt http://en.wikipedia.org/wiki/Image:Lasvegasgeography.jpg http://www.geology.wisc.edu/~chuck/Classes/Mtn_and_Plates/mt http://geology.isu.edu/Digital_Geology_Idaho/Module5/mod5.htmns_westernUS.html
Cordilleran Orogeny 3rd phase: Laramide orogeny Why?? Uplift of basement rock and overlying sediments Located further east Why?? Very shallow angle thrust No melting Transfer of compressional forces Sheep Mtn anticline, WY http://www.geol.umd.edu/~tholtz/G102/102meso2.htm http://www.geology.wisc.edu/~maher/air/air15.htm
Cordilleran Orogeny http://pubs.usgs.gov/dds/dds-81/Intro/TopographicData/DEM/DEM.html http://www.umt.edu/geosciences/faculty/sears/animation/latecretaceous.htm
Interior Craton Interior Seaway in late Cretaceous Covered ~1/3 land area Marine carbonate deposition Niobrara Fmn Oil, coal, gas origins Niobrara Fmn, KS Morrison Fmn Morrison formation with white/pink Navajo sandstone in distance. http://cedarandsand.blogspot.com/feeds/posts/default http://www.geo.wvu.edu/~wilson/geol1/lec43b/EHist7.htm http://esp.cr.usgs.gov/research/fossils/ammonites.html
Life in the Mesozoic: Marine Seafloor Paleozoic fauna gone Bryozoans, crinoids, blastoids, tabulates, fusulinids ‘Marine revolution’ Bivalves, gastropods took over Ex: Inoceramids Crinoids replaced by spiny or burrowing echinoids Reef builders Scleractinid corals dominate early Rudistids clams dominated later http://www.geo.vu.nl/~smit/inoceramus/inoceramid.htm http://www.ucmp.berkeley.edu/cnidaria/scleractinia.html http://www.geol.umd.edu/~jmerck/geol100/lectures/31.html http://www.humboldt.edu/~natmus/lifeThroughTime/Cretaceous.web/index.htm
Mesozoic Life: Water Column Ammonoids Changes in suture designs Zig-zag to U-shaped to branched Mesozoic index fossil Belemnites ‘ancient’ squids Planktonic life Diatoms Coccolithophores Foraminiferans: globigerinids http://www.abc.net.au/dinosaurs/fact_files/ea/sealife/belemnite.htm http://www.bedfordmuseum.org/collections/fossils/belemnites_2.htm
Marine Vertebrates Bony fishes Reptiles Primitive sturgeons Teleosts with mobile jaws, swim bladders Ex: Xiphactinus Reptiles Plesiosaurs Large reptiles Ichthyosaurs Completely aquatic (live births) Mosasaurs http://www.bbc.co.uk/science/seamonsters/factfiles/xiphactinus.shtml http://www.artistwd.com/joyzine/australia/articles/dinosaurs/freshwater_plesiosaur.php http://www.exn.ca/dinosaurs/story.asp?id=2000032152&name=creatures
Marine Vertebrates Megalodon (shark) Great White relative http://www.fossilien.de/seiten/haizaehne/megalodon.htm