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Pleistocene Glacio-Eustatic Fluctuations and Global Correlation of Continental Margin Sediments

This study investigates the possibility of globally correlating continental margin sediments during Pleistocene glacio-eustatic fluctuations using the seismic stratigraphic model. It aims to determine if genetically related sedimentary units bounded by unconformities can be used as a chronological tool and if there is a one-to-one correlation between regional unconformities and global average sea level.

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Pleistocene Glacio-Eustatic Fluctuations and Global Correlation of Continental Margin Sediments

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  1. Can continental margin sediments be globally correlated during Pleistocene glacio-eustatic fluctuations? Cecilia M. McHugh Queens College City University of New York & The Graduate Center of CUNY

  2. Scientific Ocean Drilling History • Project Mohole: 1958-1966 • Deep Sea Drilling Program: 1968-1983 • 1968-1973: US funded • 1973-1983: International • Ocean Drilling Program: 1985-2003 • Integrated Ocean Drilling Program: 2003-2013 • International Ocean Discovery Program: 2013-2023

  3. Multiple Platforms • JOIDES Resolution • Operated by the U.S. • Riserless Platform • Chikyu • Operated by Japan • Riser Platform • Mission Specific Platforms • Platform chosen based on scientific objective • Operated a consortium of European countries

  4. Types of platforms IODP operates • Riser drilling provides an extension from the sea-floor to the platform including a blowup preventer. You can drill deeper and safer if there is gas • Special platform can be any type of platform that is required to full fill the needs of the program for example, ice breakers

  5. R/V Joides Resolution

  6. Life on board

  7. Practice Drills

  8. Fun and games Fun things

  9. Marine Life

  10. Ship has a big hole in the middle “moon pool”. The pipes go from the dereck through the drilling platform, moon pool to the sea-floor and beneath

  11. Drilling Operations

  12. Liners 9.5 m long are split in 1.5 m sections and in halves: working and archive

  13. Photographed, described, put into D-Tubes and refrigerated

  14. How to Participate • Sail as shipboard scientists and technicians • Serve on IODP science advisory panels • Serve on the US Science Advisory Committee • Request samples and data for research • Graduate student opportunities: • Apply to sail • Schlanger Ocean Drilling Fellowships • Assist in post-cruise research http://usoceandiscovery.org

  15. Scientific Ocean Drilling Sea Level on Passive Margins • Initially DSDP Legs 80 (Ireland) 93 and 95 to the New Jersey Continental Margin • Ocean Drilling Program Sea-Level Transect Legs 150, 150X and 174A, 174AX to the New Jersey Continental Margin • Integrated Ocean Drilling Program Expedition 313 to the New Jersey Continental Margin • Integrated Ocean Drilling Program Expedition 317 to the Canterbury Basin offshore the Southern Island, New Zealand

  16. Scientific Ocean Drilling Sea Level on Passive Carbonate Margins • DSDP Legs 133, 194 (Australia) 166 (Bahamas)

  17. Collaborators • Craig Fulthorpe • Greg Mountain • Ken Miller • Jed Damuth • Peter Blum • Koichi Hoyanagi • Hilary Olsen • Science Party ODP Legs 150, 150X, 174A • Science Party IODP Expeditions 317 • Yolanda Choi • Katherine Mishkin • Jennifer Rios • Alexandrea Fortin • Diana Morgan • Corinne Hartin • Helene Gould • George Lozefski • Dee Breger • Lenny Canone • Pat Malone

  18. Background

  19. Big Questions • How do continental margins form and evolve in response to Pleistocene glacio-eustatic fluctuations? • Sedimentation in continental margins is controlled by global average sea level change • As a result of shoreline migration it is very challenging to correlate events across a margin • The seismic stratigraphic model proposed by oil industry is powerful in that it provides a means of linking shallow and deep water settings within a glacio-eustatic cycle or longer time spans (e.g., Vail et al., 1977)

  20. We want to test the Seismic Stratigraphic Model • Depositional sequence formed by genetically related sediments bounded above and below by unconformities (Vail et al., 1977) • A chronostratigraphic unit related to global average sea level (eustasy) high stand low stand transgressive maximum flooding surface sequence boundary Adapted from Van Wagoner et al., 1999

  21. Big Questions • Can the seismic stratigraphic model sequences (genetically related sedimentary units) that are bounded by unconformities be used as a chronological tool? • Is there a one-to-one correlation between the formation of regional unconformities and global average sea level (eustasy)? • Can margin wide unconformities be globally correlated?

  22. Background: Prior to drilling

  23. What is preserved in the sedimentation record? Accommodation space: sediment supply, climate, global average sea level (eustasy) and total subsidence climate sediment supply eustasy= global average sea level sediment loading compaction uplift thermal cooling Total Subsidence

  24. What is preserved in the sedimentation record? • Total subsidence accounted for • For ODP and IODP studies the focus was on passive margins that have undergone thermal subsidence • Backstripping: remove the effects of loading Steckler et al., 1999

  25. Obtain seismic grids Determine accommodation space Sea-floor

  26. Seismic stratigraphers define the depositional sequence based on angular terminations of stratal surfaces; onlap, downlap, toplap

  27. Based on these background studies and techniques regional unconformities and sequences are mapped MCS profiles ODP Leg 174A Mountain et al., 2007

  28. Addressing the Questions by drilling: Linking seismics to the lithology • Find out if there is a one-to-one correlation between global sea level and seismic sequences • Must establish correlations of unconformities across margins • Facies successions must be identified and dated at proper resolution • Evaluate the role of accommodation space in sediment preservation

  29. Lithology – Seismically Defined Sequence Boundaries New Zealand IODP 317 Fulthorpe, Hoyanagi, Blum and the Expedition 317 Scientists, 2011 Fulthrope et al., 2011

  30. I. Define unconformities-sequence boundaries from the lithology • Physical evidence • Sharp unconformable contacts • Lag gravels, phosphorites • Shell beds/hash • Rip-up clasts • Mass-wasting • Extensive burrowing and bioturbation • Missing lithofacies from faciessuccession • Dramatic paleodepthchanges • Must show geographic distribution (not local surface) Pleisto MIS-16 610 ky Plio Mio Pleisto MIS-15 680 ky IODP 317 - Site 1352 Fulthorpe et al., 2011

  31. II. Identify typical Pleistocene lithofacies succession IODP Expedition 317 Canterbury Basin, New Zealand McHugh et al., 2017

  32. Interpret Pleistocene facies succession within a sea-level context McHugh et al., 2017

  33. III. Develop a chronology from deep sea benthic foraminiferal

  34. The chronology is obtained by constructing an oxygen isotope record or d18O: Reflects the ratio of heavy to light isotopes Stable isotopes of oxygen 16O 8 neutrons and 8 protons (17O 9 neutrons and 8 protons) 18O 10 neutrons and 8 protons The ocean past and present contains both kinds

  35. The d18O reflects the ratio of heavy to light isotopes: Mainly ice volume

  36. Correlate our oxygen isotope record to a previously developed and dated d18O record PLIOCENE LR04 Benthic d18O stack Lisiecki and Raymo 2005

  37. Once the scale is developed we date it through biostratigraphy Plant-like protists Animal-like protists calciumcarbonate(CaCO3) coccoliths forams appx 1 µm appx 50 µm biogenicsilica(bSiO2) diatoms radiolaria appx 50 µm appx 50 µm

  38. Example of nannoplankton abundance and ages E. Huxleyi Site 1352 P. Lacunosa Fulthorpe et al., 2011

  39. For older strata we use 87Sr/86Sr isotopes- Polarity Chrons • For older part of the record Miocene, Oligocene, Eocene, Sr isotopes have been successfully used (Browning et al., 2008) with resolution of more than 1My • Magnetostratigraphy

  40. Final Product is a chronology constructed from deep sea benthic foraminiferal d18O records -Oligocene and younger agrees well with sea level astronomically tuned Cibicidoides records - astronomically tuned Cibicidoides records adjusted to Pacific values Miller et al. (in prep).

  41. Study Areas • Canterbury Basin offshore the South Island, New Zealand • New Jersey margin, Western Mid-Atlantic Ocean • Both margins are mid-latitude siliciclastics • Classic passive margins that have undergone thermal subsidence (New Zealand younger) • Are comparable because the same geophysical data acquisition techniques, interpretations and litholgic analyses were used • Both are slope sites

  42. Canterbury Basin Sea-level Expedition 317

  43. New Zealand Fulthorpe et al., 2011 • Sedimentation influenced by local currents: Northward flowing Southland Current, Antarctic Circumpolar Current, variable SubantarcticFront, strong long shore currents • Downslope processes • Distal tectonics related to the formation of the Alpine Fault and rise of the New Zealand Alps in Miocene Transect of Sites across shelf and upper slope (85-340 m) Lu and Fulthorpe, 2004

  44. New Zealand • Lu and Fulthorpe (2004) interpreted 19 Mid-Miocene to Recent sequence boundaries U1-U19 • The focus is on the Pleistocene sequences U13-U19 with eroded and incised paleoshelves with more pronounced rollovers • We drilled a transect of Sites across the shelf and upper slope Fulthorpe et al., 2011

  45. Lithology: Focus on Pleistocene for age resolution Fulthorpe, Hoyanagi, Blum and the Expedition 317 Scientists, 2011 Fulthorpe et al., 2011

  46. New Zealand slope Site 1352 • Correlated the elemental chemistry to calcium carbonate and grain size to define lithofacies • Ca/Ti as terrigenous proxy • Ca/Sr as marine proxy McHugh et al., 2017 McHugh et al., 2017

  47. Interpret Pleistocene facies successions within a sea-level context McHugh et al., 2017

  48. Correlate sequence boundaries interpreted from the seismicswith basal contacts (Types 1 and 2) obtained from the lithology McHugh et al., 2017 There are more basal contacts than sequence boundaries

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