@article {2919,
	title = {Aquifer-Scale Observations of Iron Redox Transformations in Arsenic-Impacted Environments to Predict Future Contamination},
	journal = {Environmental Science \& Technology Letters},
	volume = {7},
	year = {2020},
	month = {Aug-12-2020},
	pages = {916 - 922},
	abstract = {Iron oxides control the mobility of a host of contaminants in aquifer systems, and the microbial reduction of iron oxides in the subsurface is linked to high levels of arsenic in groundwater that affects greater than 150 million people globally. Paired observations of groundwater and solid-phase aquifer composition are critical to understand spatial and temporal trends in contamination and effectively manage changing water resources, yet field-representative mineralogical data are sparse across redox gradients relevant to arsenic contamination. We characterize iron mineralogy using X-ray absorption spectroscopy across a natural gradient of groundwater arsenic contamination in Vietnam. Hierarchical cluster analysis classifies sediments into meaningful groups delineating weathering and redox changes, diagnostic of depositional history, in this first direct characterization of redox transformations in the field. Notably, these groupings reveal a signature of iron minerals undergoing active reduction before the onset of arsenic contamination in groundwater. Pleistocene sediments undergoing postdepositional reduction may be more extensive than previously recognized due to previous misclassification. By upscaling to similar environments in South and Southeast Asia via multinomial logistic regression modeling, we show that active iron reduction, and therefore susceptibility to future arsenic contamination, is more widely distributed in presumably pristine aquifers than anticipated.},
	keywords = {BANGLADESH, BENGAL BASIN, groundwater, PLEISTOCENE AQUIFER, POLLUTION, RELEASE, RIVER DELTA, Sediment, TRANSPORT, VIETNAM},
	issn = {2328-8930},
	doi = {10.1021/acs.estlett.0c0067210.1021/acs.estlett.0c00672.s00110.1021/acs.estlett.0c00672.s00210.1021/acs.estlett.0c00672.s00310.1021/acs.estlett.0c00672.s004},
	url = {https://apps.webofknowledge.com/InboundService.do?product=WOS\&Func=Frame\&DestFail=http\%3A\%2F\%2Fwww.webofknowledge.com\&SrcApp=search\&SrcAuth=Alerting\&SID=8AkJOJLKFU3j5nkGaRI\&customersID=Alerting\&mode=FullRecord\&IsProductCode=Yes\&AlertId=4d48b20a-7d27-4fa2-},
	author = {Nghiem, Athena A. and Shen, Yating and Stahl, Mason and Sun, Jing and Haque, Ezazul and DeYoung, Beck and Nguyen, Khue N. and Thi Mai, Tran and Trang, Pham Thi Kim and Pham, Hung Viet and Mailloux, Brian and Harvey, Charles F. and van Geen, Alexander and Bostick, Benjam{\'\i}n C.}
}
@article {2669,
	title = {The southern Gulf of Mexico: A baseline radiocarbon isoscape of surface sediments and isotopic excursions at depth},
	journal = {PLOS ONE},
	volume = {15},
	year = {2020},
	month = {Mar-04-2021},
	pages = {e0231678},
	abstract = {The southern Gulf of Mexico (sGoM) is home to an extensive oil recovery and development infrastructure. In addition, the basin harbors sites of submarine hydrocarbon seepage and receives terrestrial inputs from bordering rivers. We used stable carbon, nitrogen, and radiocarbon analyses of bulk sediment organic matter to define the current baseline isoscapes of surface sediments in the sGoM and determined which factors might influence them. These baseline surface isoscapes will be useful for accessing future environmental impacts. We also examined the region for influence of hydrocarbon deposition in the sedimentary record that might be associated with hydrocarbon recovery, spillage and seepage, as was found in the northern Gulf of Mexico (nGoM) following the Deepwater Horizon (DWH) oil spill in 2010. In 1979, the sGoM experienced a major oil spill, Ixtoc 1. Surface sediment δ13C values ranged from -22.4{\textperthousand} to -19.9{\textperthousand}, while Δ14C values ranged from -337.1{\textperthousand} to -69.2{\textperthousand}.
Sediment δ15N values ranged from 2.8{\textperthousand} to 7.2{\textperthousand}, while the \%C on a carbonate-free basis ranged in value of 0.65\% to 3.89\% and \%N ranged in value of 0.09\% to 0.49\%. Spatial trends for δ13C and Δ14C were driven by water depth and distance from the coastline, while spatial trends for δ15N were driven by location (latitude and longitude). Location and distance from the coastline were significantly correlated with \%C and \%N. At depth in two of twenty (10\%) core profiles, we found negative δ13C and Δ14C excursions from baseline values in bulk sedimentary organic material, consistent with either oil-residue deposition or terrestrial inputs, but likely the latter. We then used 210Pb dating on those two profiles to determine the time in which the excursion-containing horizons were deposited. Despite the large spill in 1979, no evidence of hydrocarbon residue remained in the sediments from this specific time period.},
	keywords = {Gulf of Mexico, hydrocarbons, Oil spills, Oils, Petroleum, Sediment},
	doi = {10.1371/journal.pone.023167810.1371},
	url = {https://www.ncbi.nlm.nih.gov/pubmed/32294128},
	author = {Bosman, Samantha H. and Schwing, Patrick T. and Larson, Rebekka A. and Wildermann, Natalie E. and Brooks, Gregg R. and Romero, Isabel C. and Sanchez-Cabeza, Joan-Albert and Ruiz-Fern{\'a}ndez, Ana Carolina and Machain-Castillo, Maria Luisa and Gracia, Adolfo and Escobar-Briones, Elva and Murawski, Steven A. and Hollander, David J. and Chanton, Jeffrey P.},
	editor = {Potter-McIntyre, Sally}
}
@article {2782,
	title = {Farming strategies of 1st millennium CE agro-pastoralists on the southern foothills of the Tianshan Mountains: A geoarchaeological and macrobotanical investigation of the Mohuchahangoukou (MGK) site, Xinjiang, China},
	journal = {PLOS ONE},
	volume = {14},
	year = {2019},
	month = {May-06-2019},
	pages = {e0217171},
	abstract = {Archaeological evidence emerging over the past decade clearly illustrates that agro-pastoralists living along the foothills of major mountain chains in Central Asia (the so-called {\textquotedblleft}Inner Asian Mountain Corridor{\textquotedblright} or IAMC) facilitated the spread of domesticated grains through their direct involvement in farming. While the environmental conditions across the northwestern slopes of the IAMC provided adequate resources for incipient farming and herding as early as the mid-3rd mill. BCE, the development of local agricultural strategies on the extremely arid and eroded foothills on the southeastern, leeward side of the mountains remain comparatively less studied. Our study tackles this problem by combining geoarchaeological analysis with conventional macrobotanical identification in the investigation of a 1st-mill. CE agro-pastoralist farming site, Mohuchahangoukou (MGK), located on the arid foothills of the Tianshan range. Our results illustrate how ancient agro-pastoralists at MGK innovated irrigation systems both to combat water shortage and, importantly, to trap sediments carried by flood-water for crop cultivation. By synthesizing currently available data, we estimate that they managed to trap about 40 cm of fine-grained sediment within a span of 200 years or even less. These stone-built field systems helped water a diverse stand of crops and create deeper soils in an otherwise deflated landscape with thin desert soils. Since we detected high levels of salt concentration (>2 dSm-1) in the lower portions of all three test trenches we analyzed, we conclude that soil salinization might have affected the long-term sustainability of this form of irrigated field management. We also infer that, besides engineering efforts, the ancient agro-pastoralists at MGK had to resolve the scheduling conflicts between irrigated farming and animal herding through labor specialization.},
	keywords = {Agricultural irrigation, Agricultural soil science, agriculture, Archaeology, Crops, Geochemistry, Paleopedology, Sediment},
	doi = {10.1371/journal.pone.0217171},
	url = {https://dx.plos.org/10.1371/journal.pone.0217171},
	author = {Li, Yuqi and Storozum, Michael and Tian, Duo and Frachetti, Michael and Su, Kai and Wang, Xin},
	editor = {Islam, Rafiq}
}
@article {2838,
	title = {Slope failures within and upstream of Lake Quinault, Washington, as uneven responses to Holocene earthquakes along the Cascadia subduction zoneAbstract},
	journal = {Quaternary Research},
	volume = {89},
	year = {2018},
	month = {Jan-01-2018},
	pages = {178 - 200},
	abstract = {Investigation of Lake Quinault in western Washington, including a reflection seismic survey, analysis of piston cores, and preliminary mapping in the steep, landslide-prone Quinault River catchment upstream of the lake, reveals evidence for three episodes of earthquake disturbance in the past 3000 yr. These earthquakes triggered failures on the lake{\textquoteright}s underwater slopes and delta front, as well as subaerial landsliding, partial channel blockage, and forced fluvial sediment aggradation. The ages of the three Lake Quinault disturbance events overlap with those of coseismically subsided, coastal marsh soils nearby in southwest Washington that are interpreted to record ruptures of the Cascadia megathrust. Absent from Lake Quinault, however, are signals of obvious disturbance from five additional subduction earthquakes inferred to have occurred during the period of record. The lack of evidence for these events may reflect the limitations of the data set derived from the detrital, river-dominated lake stratigraphy but may also have bearing on debates about segmentation and the distribution of slip along the Cascadia subduction zone during prior earthquakes.},
	keywords = {Cascadia, Earthquake, lakes, Paleoseismic, Sediment},
	issn = {0033-5894},
	doi = {10.1017/qua.2017.96},
	url = {https://www.cambridge.org/core/product/identifier/S0033589417000965/type/journal_article},
	author = {Leithold, Elana L. and Wegmann, Karl W. and Bohnenstiehl, Delwayne R. and Smith, Stephen G. and Noren, Anders and O{\textquoteright}Grady, Ryan}
}
@book {2724,
	title = {Using Stable and Radiocarbon Analyses as a Forensic Tool to Find Evidence of Oil in the Particulates of the Water Column and on the Seafloor Following the 2010 Gulf of Mexico Oil Spill},
	year = {2018},
	pages = {639 - 650},
	publisher = {Elsevier},
	organization = {Elsevier},
	abstract = {Over 600 million liters of oil and copious amounts of methane were released into the Gulf of Mexico between April 20, 2010 and July 15, 2010. We used stable and radiocarbon analyses as a forensic tool to trace these hydrocarbons from the Deepwater Horizon (DwH) well into suspended particulate organic carbon (POCsusp), sinking particulate organic carbon (POCsink), and sedimentary organic carbon on the seafloor. POCsusp samples were considerably depleted both in δ13C and Δ14C relative to surface production, with δ13C and Δ14C values as low as -37.2{\textperthousand} and -618{\textperthousand}, respectively. POCsink time series data revealed a modern Δ14C value due to a large diatom bloom in early September 2010, but values became depleted as oil contaminated particles continued to descend in the water column until the end of the year. Sediment cores collected in the vicinity of the DwH wellhead revealed evidence of oil contamination in the surface layer (0{\textendash}1 cm), as indicated by a depletion in Δ14C values compared to the layers below the surface. In addition to providing evidence of oil contamination using stable and radiocarbon analyses, our study was consistent with the existence of a pathway by which spilled oil was deposited onto the seafloor.},
	keywords = {Deepwater Horizon, isotopes, methane, Petrocarbon, POCsin, POCsusp, Sediment},
	isbn = {9780128044346},
	doi = {10.1016/B978-0-12-804434-6.00029-X},
	url = {https://linkinghub.elsevier.com/retrieve/pii/B978012804434600029X},
	author = {Bosman, Samantha H. and Chanton, Jeffrey P. and Rogers, Kelsey L.}
}
@article {2844,
	title = {A 7000-year history of coastal environmental changes from Mexico{\textquoteright}s Pacific coast: A multi-proxy record from Laguna Mitla, Guerrero},
	journal = {The Holocene},
	volume = {27},
	year = {2017},
	month = {Sep-08-2017},
	pages = {1214 - 1226},
	abstract = {The lack of multi-millennial multi-proxy paleoenvironmental reconstructions from Mexico{\textquoteright}s Pacific coast has limited our understanding of the regional response to climate change and sea-level rise. A 479-cm core covering the last 6900 years was extracted from Laguna Mitla in the state of Guerrero on Mexico{\textquoteright}s Pacific coast. Beginning as a Rhizophora-dominated salt pan ~6900 yr BP, at ~6500 yr BP, the site transitioned to a mangrove swamp dominated by Laguncularia, which lasted about 300 years. The beach barrier formed from ~6200 to 5200 yr BP, during which time, the site existed as an intermittently sheltered bay, the result of large, rapid changes in wave energy associated with the shifting barrier location and changes in stability. After the beach barrier was stabilized at ~5200 yr BP, water level at the coring site became a function of precipitation rather than sea level. Since that time, deposition has alternated between peat, laid down in a mangrove swamp, and clay intervals characterized by high concentrations of titanium and a predominantly regional pollen signal, representing open-water lagoon phases. Seven periods of increased water level, varying in duration, occurred during the backbarrier period, with El Ni{\~n}o-Southern Oscillation (ENSO) likely the main climatic mechanism causing these periodic shifts in the paleo-precipitation levels. We suggest that the deepest water levels detected over the last ~3200 years correlate with periods of increased ENSO activity. The spatial distribution of tropical cyclone rainfall, which represents a significant percentage of total annual precipitation along Mexico{\textquoteright}s Pacific coast, may explain the inconsistencies between our record and paleoclimatic records from Mexico{\textquoteright}s interior, but more work is needed to test this hypothesis.},
	keywords = {El Nino-Southern Oscillation, Laguna Mitla, mangroves, Pacific coast of Mexico, Paleoclimate, paleoenvironmental reconstruction, pollen, Sediment, tropical cyclones, x-ray fluorescence},
	issn = {0959-6836},
	doi = {10.1177/0959683616687379},
	url = {http://journals.sagepub.com/doi/10.1177/0959683616687379},
	author = {Bianchette, Thomas A and McCloskey, Terrence A and Liu, Kam-biu}
}
@article {2528,
	title = {A high resolution record of rare earth element compositional changes from the mud deposit on the inner shelf of the East China Sea: Implications for paleoenvironmental changes},
	journal = {Quaternary International},
	year = {2017},
	month = {Jan-01-2017},
	abstract = {A paleoenvironmental reconstruction of the East China Sea (ECS) is presented using rare earth element (REE) analysis of sediments from Core MZ02, which was retrieved from the inner continental shelf{\textquoteright}s mud area. The analytic results show that the total REEs in the fine sediment vary between 137.76 μg/g and 231.53 μg/g with an average value of 187.69 μg/g. Obvious changes were found during the process of sedimentation. By comparing with the REE compositions from the potential provenances, the ratios of (La/Sm)ucc and (Gd/Yb)ucc revealed that the sediments were mainly derived from river detrital outputs of the Changjiang (Yangtze River), Minjiang and mountainous rivers from western Taiwan Island. The contributions of terrestrial materials from these three main provenances were controlled by sea level change and the Taiwan Warm Current (TWC)-Chinese Coastal Current (CCC) system, which is mainly driven by the East Asian monsoon. The high sedimentation rate during the transgression period between the late Pleistocene and early Holocene (13000{\textendash}9800 a B.P.) was caused by a well-proportioned mixed provenance from Changjiang, western Taiwanese rivers and Minjiang sediments, due to the lower sea level and the location of the foreshore-nearshore face. Because of the stronger sediment reworking and erosion at the shelf edge during the early Holocene (9800{\textendash}7300 a B.P.), the strengthening summer East Asian monsoon transported the Minjiang and western Taiwanese river material northeastward, and it became the main sediment source for fine sediments in the shallow sea region of the ECS, while the Changjiang provided a relatively minor amount of detrital sediment to the shelf. The increasing strength of the TWC might have played an important role in sediment dispersal and deposition on the ECS inner shelf during the period 7300{\textendash}3500 a B.P., thus mountainous river material became the dominant sediment on the shelf of the ECS. Furthermore, the results indicate that the East Asian monsoon and the weakening of the TWC were linked to an abrupt increase in Changjiang-derived terrigenous detritus material since 3500 a B.P.; the source and sink pattern during this period is consistent with the modern sedimentation environment.},
	keywords = {East China Sea, Mud deposit, Paleoenvironmental, Provenance, Rare earth element, Sediment},
	issn = {10406182},
	doi = {10.1016/j.quaint.2016.09.056},
	url = {https://doi.org/10.1016/j.quaint.2016.09.056},
	author = {Mi, Beibei and Liu, Shengfa and Shi, Xuefa and Li, Xiaoyan and Pan, Hui-Juan and Chen, Min-Te and Wang, Xuchen}
}
@article {2003,
	title = {Input of particulate organic and dissolved inorganic carbon from the Amazon to the Atlantic Ocean},
	journal = {Geochemistry Geophysics Geosystems},
	volume = {6},
	year = {2005},
	note = {909pwTimes Cited:17
Cited References Count:21
},
	month = {Mar 18},
	abstract = {We report concentrations and isotope measurements (radiocarbon and stable carbon) of dissolved inorganic carbon (DIC) and suspended particulate organic carbon (POC) in waters collected from the mouth of the Amazon River and the North Brazil Current. Samples were collected in November 1991, when the Amazon hydrograph was at its annual minimum and the North Brazil Current had retroflected into the equatorial North Atlantic. The DIC D 14 C results revealed postbomb carbon in river and ocean waters, with slightly higher values at the river mouth. The low DIC delta(13)C signature of the river end-member (-11\%) demonstrates that about half of the DIC originated from the remineralization of terrestrially derived organic matter. A linear relationship between DIC and salinity indicates that DIC was mixed nearly conservatively in the transition zone from the river mouth to the open ocean, though there was a small amount (<= 10\%) of organic matter remineralization in the mesohaline region. The POC Delta(14)C values in the river mouth were markedly lower than those values from the western Amazon region (Hedges et al., 1986). We conclude that the dominant source of POC near the river mouth and in the inner Amazon plume during November 1991 was aged, resuspended material of significant terrestrial character derived from shelf sediments, while the outer plume contained mainly marine-derived POC.},
	keywords = {accumulation, amazon, C-14, carbon cycling, CO2, continental-shelf, poc, radiocarbon, river system, Sediment, total co(2), water},
	isbn = {1525-2027},
	doi = {10.1029/2004GC000842},
	author = {Druffel, E. R. M. and Bauer, J. E. and Griffin, S.}
}
@article {2049,
	title = {Characterization of Siberian Arctic coastal sediments: Implications for terrestrial organic carbon export},
	journal = {Global Biogeochemical Cycles},
	volume = {18},
	year = {2004},
	note = {806knTimes Cited:99
Cited References Count:51
},
	month = {Mar 10},
	abstract = {Surface sediments were collected during the 2000 TransArctic Expedition along the Siberian Arctic coastline, including the Ob, Yenisey, Khatanga, Lena, and Indigirka estuaries. Sediments were characterized for elemental composition (total organic carbon, TOC, black carbon, BC, and total N, as well as major and trace elements), isotopic signature (delta(13)C, delta(15)N, Delta(14)C, epsilon(Nd), Sr-87/Sr-86), and organic molecular composition to better understand river export variations over the large spatial scale of the Siberian Arctic. On average, 79 +/- 9\% of the total C in sediments was organic while 21 +/- 9\% was inorganic. BC made up 9 +/- 4\% of the TOC pool, with a general increasing trend from west to east along the Siberian coast. The combined Nd- and Sr-isotopes (epsilon(Nd) and Sr-87/Sr-86) were used to define two distinct sediment sources between east and west Siberian regions with the Khatanga River as a boundary. Data from pyrolysis-GC/MS of the sedimentary organic carbon (SOC) indicated an increase in the freshness of the organic matter from west to east on the Siberian Arctic coast, with increasing relative abundance of furfurals (polysaccharides) with respect to nitriles. Values for the delta(13)C of SOC ranged from -27.1\% (mostly terrigenous) to -23.8\%, while delta(15)N increased from east to west (3.1 to 5.2\%) with a significant correlation with C/N ratio. Values for the Delta(14)C of SOC ranged from -805 to -279\%, with a consistent trend increasing from the east (Indigirka River) to the west (Ob River). These D 14 C values corresponded to a 14 C age of 2570 +/- 30 yBP in the Ob estuary and 13,050 +/- 50 yBP in the Indigirka estuary. Most importantly, D 14 C values were significantly correlated with the ratio of BC/TOC (R-2 = 0.91, n = 6), consistent with the distribution pattern of increasing permafrost zone from the west to the east along the Siberian coast. Together, our results suggest that older OC was derived from the release of recalcitrant BC during permafrost thawing and riverbank and coastal erosion, likely enhanced by ongoing environmental changes in the northern ecosystem.},
	keywords = {arctic ocean, BLACK CARBON, climate, CO2, continental-shelf, flux, isotopic composition, lena river, MATTER, ocean, organic carbon, quantification, Sediment},
	isbn = {0886-6236},
	doi = {10.1029/2003GB002087},
	url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2\&amp;SrcAuth=Alerting\&amp;SrcApp=Alerting\&amp;DestApp=WOS\&amp;DestLinkType=FullRecord;UT=WOS:000220432900001},
	author = {Guo, L. D. and Semiletov, I. and Gustafsson, O. and Ingri, J. and Andersson, P. and Dudarev, O. and White, D.}
}
@article {2083,
	title = {Penetration of anthropogenic carbon into organic particles of the deep ocean},
	journal = {Geophysical Research Letters},
	volume = {30},
	year = {2003},
	note = {709dpTimes Cited:12
Cited References Count:29
},
	month = {Jul 23},
	pages = {1744},
	abstract = {[1] In the late 1980s, bomb C-14 was present in suspended particulate organic carbon (POC) from the North Central Pacific (NCP) and Sargasso Sea ( SS) throughout most of the water column, demonstrating that deep POC had exchanged with atmospheric CO2 in the past 30 years. Upon reoccupation of these sites in 1999 and 2000, respectively, we observed that the delta(13)C values of suspended POC were lower than those measured a decade earlier. This demonstrates that anthropogenic CO2 from fossil fuel and biomass burning has penetrated a major organic matter pool in the deep ocean. Delta(14)C measured in the suspended POC showed similar or higher values in the deep Sargasso Sea and decreased values in the deep NCP compared to those measured previously. We use a box model to show that the differences in the radiocarbon results are likely due to the presence of resuspended sediment that is laterally advected from the continental margin to the deep Sargasso Sea.},
	keywords = {bomb radiocarbon, C-14, CO2, delta-c-13, MATTER, NORTH PACIFIC-OCEAN, SARGASSO SEA, Sediment, variability, water},
	isbn = {0094-8276},
	doi = {10.1029/2003GL017423},
	author = {Druffel, E. R. M. and Bauer, J. E. and Griffin, S. and Hwang, J.}
}
@article {911,
	title = {Identification of a novel alkenone in Black Sea sediments},
	journal = {Organic Geochemistry},
	volume = {32},
	year = {2000},
	note = {id: 1719},
	pages = {633-645},
	abstract = {We report the identification of a novel long-chain ketone in Holocene Black Sea sediments. Based on chemical properties, and chromatographic and mass spectrometric characteristics, this compound has been identified as a di-unsaturated C36 ethyl ketone. Further analyses indicated the position and configuration of the double bonds, and the novel alkenone was determined to be hexatriaconta-(16E,21E)-dien-3-one. While this compound is present in only trace quantities in Unit I sediments, it is the most abundant alkenone in portions of Unit II. Its presence thus apparently pre-dates the invasion of Emiliania huxleyi in the Black Sea. The down-core profiles and isotopic compositions suggest that the precursor for the C36:2 alkenone may be distinct from that of the C37-39 alkenones, however the biological origin of this novel compound is presently unknown.},
	keywords = {Alkenone, Black Sea, Haptophytes, Holocene, Sediment, Structure characterization},
	doi = {10.1016/S0146-6380(01)00019-5},
	author = {Xu, L. and Reddy, C. M. and Farrington, J. W. and Frysinger, G. S. and Gaines, R. B. and Johnson, C. G. and Nelson, R. K. and Eglinton, T. I.}
}
