Cataloging Microfossils of Yakutat Bay, Alaska

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Cataloging Microfossils of Yakutat Bay, Alaska
Alexander D. Ullrich Dept. of Geology Appalachian
St. University Boone, NC
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Field Setting

• Yakutat Bay, Alaska
• Hubbard Glacier-
• Tidewater glacier emptying into Disenchantment
  Bay, AK.
• High turbidity high sed. discharge
• Low salinity
• Summer discharge causes thick mud layers
• Iceberg calving causes winter diamicton layers

Study Area
http//northlandsvs.com/
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Catalog of foraminifera

• Distal Multicore chosen
• High-density, high diversity
• Picked 300 individual population

Multicore 8
Multicorer on R/V Alpha Helix tailfan
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Microfossils

• Tiny remains of bacteria, fungi, animals, plants,
  and protists
• Extremely useful as environmental indicators
• Foraminifera in particular
• Species indicate salinity, high/low energy,
  bathymetry, DO content, temperature
• Seasonal variation

http//woodshole.er.usgs.gov/epubs/bolide/ancient_
cataclysm.html
http//ijolite.geology.uiuc.edu/02SprgClass/geo117
/Ocean20images/Microfoss.html
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Foraminifera

• Single-celled protists with shells (tests),
  called forams or bugs (Phylum Protozoa)
• Consume algae, diatoms, other protists by
  extending protoplasm through aperture in test
  (psuedopodia)
• Protoplasm is inside test chamber (chambers added
  as foram grows)
• Often used in age-dating and correlation of rock
• Extant species used to interpret environments and
  climates

http//www.soton.ac.uk/bam2/col-index/fossi-linde
x/Forams/Eelco/med-agean2/pages/pl-02.htm
Pseudopodia
Protoplasm
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Results Genera and Species Classification
Distinguishing features of a genus

• Planktic vs. Benthic

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Results Genera and Species Classification
Distinguishing features of a genus

• Planktic vs. Benthic
• Agglutinated test vs. secreted test

agglutinated
secreted
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Results Genera and Species Classification
Distinguishing features of a genus
Limbate

• Planktic vs. Benthic
• Agglutinated test vs. secreted test
• Limbate/Costate structures

Costate
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Results Genera and Species Classification
Distinguishing features of a species

• Morphology of Aperture

(Echols and Armentrout, 1980)
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Results Genera and Species Classification
Distinguishing features of a species

• Morphology of Aperture
• Coiling of test
• Planispiral
• Involute
• Trochospiral

http//www.andreaperl.de/14_69_ammoniahtml.html
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Results Genera and Species Classification
Distinguishing features of a species

• Morphology of Aperture
• Coiling of test
• Evolute
• Involute
• Trochospiral
• Streptospiral
• Other morphological features (costate protrusion,
  limbate thickness, papillate presence, etc.)

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Plate 1 Abundant Genera

• 1,2,3. Elphidium sp.A, 1000x
• 4,8. Buccella sp. A, 1000x
• 5,6. Epistominella sp. A, dextral, 1000x
• Epistominella sp. A, sinistral, 1000x
• 9,10. Cassidulina minuta, 1000x
• 11, 12. Neogloboquadrina pachyderma, 1200x,
  1100x
• 13, 14. Nonionella stella, 400x
• 15, 16. Nonionella labridorica, 400x

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Plate 2 Limited Genera

• 1,2. Cribrostomoides sp. A, 1000x
• Spiroplectammina sp. A, 1300x
• Lagena sp. A, 500x
• Triloculina sp. A, 700x
• Triloculina sp. B, 400x
• Bulimina sp. A, 400x
• Bulimina sp. A, 200x
• Fissurina sp. A, 1000x
• Fissurina sp. A, 700x
• Uvigerina sp. A, 250x

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Plate 3 Forams under a light microscope

• 1,2. Nonionella labridorica, 40x
• 3,4. Nonionella stella, 40x
• 5,6. Buccella sp. A, 51x
• Epistominella sp. A, 51x
• Bulimina sp. A, 51x
• Cribrostomoides sp. A, 32x
• Cassidulina limbata, 40x
• Cassidulina norcrossi, 40x
• Cassidulina sp. A, 40x
• Cassidulina minuta, 64x

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Conclusions
Goals included

• Gaining experience in SEM techniques and theory

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Conclusions
Goals included

• Gaining experience in SEM techniques and theory
• Foram picking techniques

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Conclusions
Goals included

• Gaining experience in SEM techniques and theory
• Foram picking techniques
• Start gathering images of representative genera
  for catalog

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Conclusions
Goals included

• Gaining experience in SEM techniques and theory
• Foram picking techniques
• Start gathering images of representative genera
  for catalogue
• All goals were accomplished during semester

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Conclusions
Goals included
Questions

• Gaining experience in SEM techniques and theory
• Foram picking techniques
• Start gathering images of representative genera
  for catalogue
• All goals were accomplished during semester

• Genera/species change from distal to proximal?

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Conclusions
Goals included
Questions

• Gaining experience in SEM techniques and theory
• Foram picking techniques
• Start gathering images of representative genera
  for catalogue
• All goals were accomplished during semester

• Genera/species change from distal to proximal?
• Environmental changes shown by distribution
  within sediment?

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Conclusions
Goals included
Questions

• Gaining experience in SEM techniques and theory
• Foram picking techniques
• Start gathering images of representative genera
  for catalogue
• All goals were accomplished during semester

• Genera/species change from distal to proximal?
• Environmental changes shown by distribution
  within sediment?
• Seasonal variation?

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• Future Research Senior Thesis
• Targeting specific foraminifera species as
  environmental indicators
• Specifically
• Elphidium excavatum forma clavatum
• Elphidium frigidum

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References

• Lipps, J.H., 1981, What,if anything, is
  micropaleontology? Paleobiology, v. 7, no. 2,
  pp. 167-191.
• Echols, R.J., and Armentrout, J.M., 1980,
  Holocene foraminiferal distribution patterns on
  the shelf and slope, Yakataga- Yakutat area
  northern Gulf of Alaska Proceedings of the
  Quaternary depositional environments of the
  Pacific Coast Pacific Coast Paleogeography
  Symposium, no. 4, pp. 281- 303.
• Bergen, F.W., and ONeil, P., 1979, Distribution
  of Holocene foraminifera in the Gulf of Alaska
  Journal of Paleontology, v. 53, no. 6, p.
  1267-1292.
• Quinterno, P., Carlson, P., and Bruce F. Molnia,
  1980, Benthic foraminifers from the eastern Gulf
  of Alaska Quaternary depositional Environments
  of the Pacific Coast Pacific Coast
  Paleogeographic Symposium 4,

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Special Thanks to

• Dr. Ruth Dewel, Dept. of Biology, ASU
• Dr. Ellen Cowan, Dept. of Geology, ASU
• Dr. Steven Hageman, Dept. of Geology, ASU
• Dr. Sarah Zellers, Dept. of Geology, MSU
• FEI Systems Technicians
• The 2005 SEM Lab class