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Permafrost cores (4.5-7.5 m long) were collected April 10th-19th, 2018, along a geomorphic gradient near Drew Point, Alaska to characterize active layer and permafrost geochemistry and material properties. Cores were collected from a young drained lake basin, an ancient drained lake basin, and primary surface that has not been reworked by thaw lake cycles. Measurements of total organic carbon (TOC) and total nitrogen (TN) content, stable carbon isotope ratios (δ13C) and radiocarbon (14C) analyses of bulk soils/sediments were conducted on 45 samples from 3 permafrost cores. Porewaters were extracted from these same core sections and used to measure salinity, dissolved organic carbon (DOC), total dissolved nitrogen (TDN), anion (Cl-, Br-, SO4 2-, NO3 -), and trace metal (Ca, Mn, Al, Ba, Sr, Si, and Fe) concentrations. Radiogenic strontium (87Sr/86Sr) was measured on a subset of porewater samples. Cores were also sampled for material property measurements such as dry bulk density, water content, and grain size fractions.
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Geochemical data from sediments and porewaters from ferruginous and meromictic Brownie Lake, Minnesota, U.S.A.
The dataset is comprised of analyses of sediment cores and sediment trap samples from ferruginous and meromictic Brownie Lake, Minnesota, U.S.A from January 2018 through February 2021. The dataset includes bulk sediment characteristics including water content, grain size, major and minor elements. Voltammetric scans were collected on porewaters and lake waters. Sediment porewaters were analyzed for pH, total alkalinity, ferrous iron, and dissolved sulfur species contents. Sediment samples were maintained under the exclusion of oxygen for analysis by synchrotron-based X-ray absorption spectroscopy.
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- PAR ID:
- 10414328
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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