discovering the past to predict and protect the future

Kinuyo Kanamaru

Contact:

Dept. of Geo Sciences
University of Massachusetts
611 North Pleasant St.
Amherst, MA 01003-9297
Phone: (413) 545-0659
Email: kinuyok@geo.umass.edu

Research:

Dec. 23, 2008 By Kinuyo

My research aims to develop a new approach for identifying seasonal to decadal-scale climatic events in terms of frequency and intensity using the elemental composition of sediment. The major and minor elemental compositions of the sediments are used to determine sediment provenance, which in turn may be useful to identify paleo-seismic events.

As a part of the IMAGES VIII (International Marine Past Global Changes Study) program, a 51-m long core, MD02-2490, was retrieved from Saanich Inlet, a silled fjord on southeastern Vancouver Island (Fig. 1). The sediments of the core are investigated using an ITRAX X-ray fluorescence (XRF) core scanner for elemental composition. The analysis is supplemented by micron-scale investigation in thin sections using backscattered electron microscope image (BSEI) measurements. Selected individual laminae on thin sections are analyzed by energy dispersive spectroscopy (EDS) to provide a better understanding of seasonal sediment provenance. An age model is established using four dating techniques: 1) stratigraphic dating, 2) tephrochronology (Mazama ash, Fig. 2), 3) radiocarbon dating, and 4) laminae counting.

Southeastern Vancouver Island is currently experiencing growing urban pressures from increased demands for marginal land use as future development sites continually expand. Further, the region is precariously situated over an active subduction zone. Therefore, the region is exposed to potentially suffering increased human, economic, and urban calamities. To prevent any impending damage to the human population, urban landscape, and economic infrastructure, it is critical to identify the frequency and magnitude of past geologic events.

FIGURES

Fig. 1. Saanich Inlet and its environment, indicating the location of sampling points: A) Saanich Inlet, B) Location map of coring sites; MD02-2490 (closed square), ODP1033 and 1034 (open square). Stations O, M, L, J, H, and B are from a hydrological study conducted by Herlinveaux (1962).


Fig. 2. Stratigraphic marker layers. A) Mazama ash layer containing volcanic grass shards and B) A base of a thick massive silty clay deposit embedded from 41.9 to 42.92 m reveal an erosional basal contact inclined at approximately 20° - 30°.


Advisor: Raymond S. Bradley, Climate System Research Center, Geoscience Department, UMass, Amherst

Co-advisor: Pierre Francus, Institut National de la Recherche Scientifique, Centre Eau, Terre et Environnement, Québec, Canada