A 520-year paleolimnological grain size and ITRAX record from Harvey Lake, New Brunswick, Canada
Cite this dataset
Patterson, R. Timothy (2022). A 520-year paleolimnological grain size and ITRAX record from Harvey Lake, New Brunswick, Canada [Dataset]. Dryad. https://doi.org/10.5061/dryad.8cz8w9gpw
This grain size data was derived from a 250 mm long gravity Glew Maxi core (HL-2017-GC-2) collected from near the mouth of Herbert's Cove, Harvey Lake, New Brunswick Canada (45°43’42.535” N; 67°01’23.739” W) at a water depth of 4.5 m. The core was subsampled on-site at 2 mm resolution using a Glew core extruder before transport to Carleton University for subsequent analysis. Subsamples were analyzed using a Beckman Coulter LS 13 320 laser diffraction grain size analyzer equipped with a universal liquid module. The resultant triplicate grain size data were averaged using a script within Matlab which generated the data archived here. The data was then analyzed using End Member Mixing Analysis and three distinct end members were recognized EM01, Mode = 05 μm; EM02, Mode = 27μm; EM03, Mode = 58 μm). Subsequent radiocarbon dating revealed that deposition spanned the last 520 years of deposition. During this interval there were 12 major storms (EM03) and analysis of precipitation data from the Harvey climate station indicated that ~110 mm of rain was required for the deposition of EM01 in Harvey Lake. The deposition of EM02 was derived from the yearly spring freshet runoff.
In preparation for grain-size analysis, 118 sediment subsamples from core HL-2017-GC-2, collected in July 2017, from 4.5 m water depth were processed at mm-stratigraphic resolution. 30% H2O2 was added to subsamples and then placed in an 80oC water bath to oxidize organic matter. Analysis of randomly selected samples treated using 10% HCl indicated that sediment carbonate content was insignificant so an HCl pretreatment was deemed unnecessary and not used. Following the H2O2 pretreatment, subsamples were analyzed using a Beckman Coulter LS 13 320 laser diffraction grain size analyzer equipped with a universal liquid module. Subsamples were hand agitated to suspend the sediments and then pipetted into the analyzer until an obscuration of 10±3% was achieved. This slurry was then circulated within the module for sixty seconds prior to the first of three replicate runs. Each sample was analyzed in triplicate resulting in grain size distributions potentially ranging from 0.4-1500 µm. The triplicate analyses were averaged for each sample and Gradistat v8 was subsequently used to generate summary statistics for the grain-size distribution data. The grainsize data were used as inputs for subsequent End Member Mixing Analysis (EMMA) where three recognized end members (EM01, Mode = 05 μm; EM02, Mode = 27μm; EM03, Mode = 58 μm) were derived from particle size data. ITRAX XRF results characterizing Glew Core 2 (2017.HC.HL.GC-2) from Herberts Cove, Harvey Lake were also measured for each subsample horizon. The Bacon age model estimated dates of deposition for each analyzed horizon are also presented, and those associated with major storms (EMO3) are shaded gray. Due to age model uncertainties there may be errors associated with the derived dates. Rainfall totals during the open water season (April-November), where >75 mm fell during single or multi-day events, were recorded from three sequential Government of Canada Climate Stations positioned in Harvey Station Station, New Brunswick spanning from 1920-2004. Lesser amounts associated with hurricane remnants known to have tracked across the area are also included.
There were some sampling gaps in the core at 0, 96, 170, 186, 190, 192, 212, 214 mm.
Natural Sciences and Engineering Research Council of Canada (NSERC), Award: RGPIN05329
Natural Resources Canada (NRCan) Clean Technology Grant, Award: CGP-17-0704
Carleton University Multidisciplinary Research Catalyst Fund , Award: 187536