Active Projects

 

UPPER NEWPORT BAY

Photo of mudflat and marsh in Upper Newport Bay.

Photo of mudflat and marsh in Upper Newport Bay.

D. Cortez collecting a core from the mudflat.

D. Cortez collecting a core from the mudflat.

T. Nguyen on the boat after collecting cores.

T. Nguyen on the boat after collecting cores.

 

Objectives:

  • Quantify seasonal sediment deposition/erosion.
  • To assess vulnerability to sea level rise by measuring sedimentation throughout the bay. 

Preliminary Findings:

  • Sediment deposited in the upper reaches of the bay during the winter is remobilized during the summer
  • Accumulation is keeping pace with relative sea level rise, but at specific locations accumulation is influenced by climate, or morphological changes

Publications:

TBA

Contributors:

  • D. Cortez (BA - CSUF), D. Van Orman (BS - CSUF), T. Nguyen (BS - CSUF)

Recent Work:

  • New cores collected June 2017 from mudflats sites!
  • Recent presentation at H2O Conference by J. Carlin (May 2017 - Irvine, CA)

LOS PENASQUITOS LAGOON

Objectives:

  • Investigate buried shell layers to determine if they are characteristic of an oyster reef community
  • Determine the driver for the shift from an open bay to a salt marsh environment

Preliminary Findings:

  • Shells within shell deposit are ecologically consistent with an oyster reef community
  • Shell characteristics may not support an in-situ reef, but if the shells were transported, it is likely not a great distance

Publications:

TBA

Contributors:

  • S. Dickson (MS - CSUF)

Recent Work:

  • Samples being prepped for radiocarbon analysis (June 2017)!
  • New cores collected in January 2017
Collecting cores in the marsh in January 2017.

Collecting cores in the marsh in January 2017.

Winter rains result in a flooded marsh even at low tide adding a new challenge to fieldwork!

Winter rains result in a flooded marsh even at low tide adding a new challenge to fieldwork!

Buried the pipe!  This core extends down more than 3 m below the surface of the marsh.

Buried the pipe!  This core extends down more than 3 m below the surface of the marsh.


seal Beach Wetlands

Map of core location in the wetlands.  

Map of core location in the wetlands.  

Paleoenvironmental reconstructions of what the wetlands might have looked like when different sedimentary units were deposited (from A. Aranda MS Thesis, 2016).

Paleoenvironmental reconstructions of what the wetlands might have looked like when different sedimentary units were deposited (from A. Aranda MS Thesis, 2016).

OBJECTIVES:

  • Utilize wetland stratigraphy to identify paleoseismic events associated with the Newport-Inglewood Fault Zone
  • Quantify the amount of co-seismic subsidence that occurs during these events

Preliminary Findings:

  • At least 3, and possibly as many as 6 co-seismic events have been preserved in the stratigraphy over the past ~2,500 years
  • Results suggest that these events require a large magnitude earthquake (>6.4 Mw)
  • Preliminary estimates of subsidence in the wetlands during such events may be 1 m or more

Publications:

Leeper, R., Rhodes, B., Kirby, M., Scharer, K., Carlin, J., Hemphill-Haley, E.,     Avnaim-Katav, S., MacDonald, G., Starratt, S., Aranda, A., 2017. Evidence for coseismic subsidence events in a southern California coastal saltmarsh. Scientific Reports 7, 44615.

Contributors:

  • R. Leeper (MS - CSUF), A. Aranda (MS - CSUF), S. Plaza (AS - Cypress College), R. Koga (BA - CSUF), M. Adler (MS - CSUF)

Recent Work:

  • Samples being prepped for radiocarbon analysis (June 2017)!
  • Foram identification underway on cores from 2013 and 2016
  • Core SB049 data shows 2-3 possible event contacts - analysis contiues