Abstract:

This dataset contains mass-to-charge ratio (m/z) and monoisotopic intensity peaks detected in the northern and southern Gulf of Mexico dissolved organic matter extracts using a Fourier transform ion cyclotron mass spectrometry (FTICR-MS). The instrument used was manufactured by Bruker Daltonics; Model: Solarix, 12T. The water samples were collected using a CTD-Niskin rosette aboard the R/V Justo Sierra cruise JS-0815 in the southern Gulf of Mexico on 2015-08-03 and aboard the R/V Weatherbird II cruise WB-0815 in the northern Gulf of Mexico on 2015-08-18. The R/V Justo Sierra cruise was led by chief scientist Dr. Steve Murawski and the R/V Weatherbird II cruise was led by chief scientist Dr. Dave Hollander. Mass-to-charge ratio (m/z) and monoisotopic intensity from a sediment core collected aboard the R/V Justo Sierra cruise JS-0815 in the southern Gulf of Mexico is available under GRIIDC UDI R4.x267.179:0006.

Suggested Citation:

Aprami Jaggi. 2019. Mass-to-charge ratio (m/z) and monoisotopic intensity from the water samples collected during R/V Justo Sierra and Weatherbird II cruises, JS-0815 and WB-0815, in the Gulf of Mexico from 2015-08-03 to 2015-08-18. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/n7-js11-zz71

Publications:

Chanton, J. P., Jaggi, A., Radović, J. R., Rosenheim, B. E., Walker, B. D., Larter, S. R., … Oldenburg, T. B. P. (2019). Mapping Isotopic and Dissolved Organic Matter Baselines in Waters and Sediments of the Gulf of Mexico. Scenarios and Responses to Future Deep Oil Spills, 160–181. doi:10.1007/978-3-030-12963-7_10

Purpose:

Identify and characterize the biogenic, abiogenic, petrogenic and pyrogenic sources of inputs and diagenetic alterations that may have occurred for the northern and southern Gulf of Mexico waters.

Data Parameters and Units:

The folder "N-GoM Water DOM" contains data collected in the northern Gulf of Mexico (N-GoM) and includes three excel files. All these files include organic characterization of the N-GoM water samples analyzed using FTICR-MS in three different ion mode (APPI = atmosphere pressure photoionization; ESI-N = electrospray ionization-negative; ESI-P = electrospray ionization-positive) in the form of the mass of organic compounds identified and their corresponding mono-isotopic intensities. Each file contains an analysis of surface and bottom waters from each site; Expt m/z (experimentally derived mass-to-charge ratio) is a dimensionless quantity formed by dividing the mass number of detected ions by its charge number. Monoisotopic intensity (Mono Inty) is the peak height of the most abundant isotopolog. The folder "S-GoM Water DOM" contains data collected in the southern Gulf of Mexico (S-GoM) and includes three excel files. All these files include organic characterization of the S-GoM water samples analyzed using FTICR-MS in three different ion mode (APPI = atmosphere pressure photoionization; ESI-N = electrospray ionization-negative; ESI-P = electrospray ionization-positive) in the form of the mass of organic compounds identified and their corresponding mono-isotopic intensities. Each file contains an analysis of surface and bottom waters from each site; Expt m/z (experimentally derived mass-to-charge ratio) is a dimensionless quantity formed by dividing the mass number of detected ions by its charge number. Monoisotopic intensity (Mono Inty) is the peak height of the most abundant isotopolog. Note: The files "N-GoM Samples in APPIp.xls" and "S-GoM Samples in APPIp.xls" includes the values in several cells with no headers. Those are the data used for calculations while doing the data analysis and can be ignored. The sample collection date and location information are as follows: Site Date of sample collection (yyyy-mm-dd) Latitude (decimal degrees) Longitude (decimal degrees) northern Gulf of Mexico 2015-08-18 29.125333 -87.260833 southern Gulf of Mexico 2015-08-03 19.370080 -92.317187

Methods:

The water samples were collected using a CTD-Niskin rosette. The collected water samples were immediately filtered using a 0.2 µm inline filter. The filtrate was acidified with hydrochloric acid (practical grade, Merck) to pH 2 and pumped through a 60 mL PPL cartridge (Agilent Bond Elut, 5 g) and extracted for dissolved organic matter (DOM). The DOM was then stored at -20°C in dark prior to analysis on the FTICR-MS. Extraction protocol: The solid phase extraction (SPE) extraction protocol for extraction of DOM from the sampled waters was developed by modifying and optimizing the methodology proposed by Dittmar et al. (2008). The collected water samples were immediately filtered using a 0.2 µm inline filter. The filtrate (~4 L for each site) was acidified with hydrochloric acid (practical grade, Merck) to pH 2 and pumped through a 60 mL PPL cartridge (Agilent Bond Elut, 5 g) at a flow rate of <40 mL/min. The DOM extracts were then eluted with 60 mL methanol (high-performance liquid chromatography; HPLC-MS grade) into pre-cleaned amber glass vials. Solvent blanks of methanol used for DOM extraction on the research vessel was analyzed on the instrument as a blank.

Instruments:

Bruker Daltonics Solarix 12T Fourier Transform Ion Cyclotron Resonance- Mass Spectrometer; CTD-Niskin rosette.

Provenance and Historical References:

Dittmar, T., Koch, B., Hertkorn, N., & Kattner, G. (2008). A simple and efficient method for the solid-phase extraction of dissolved organic matter (SPE-DOM) from seawater. Limnology and Oceanography: Methods, 6(6), 230–235. doi:10.4319/lom.2008.6.230

Individual Files: