Filters: Tags: organic matter (X)
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Solid organic matter (OM) in sedimentary rocks produces petroleum and solid bitumen when it undergoes thermal maturation. The solid OM is a 'geomacromolecule', usually representing a mixture of various organisms with distinct biogenic origins, and can have high heterogeneity in composition. Programmed pyrolysis is a common conventional method to reveal bulk geochemical characteristics of the dominant OM while detailed organic petrography is required to reveal information about the biogenic origin of contributing macerals. Despite advantages of programmed pyrolysis, it cannot provide information about the heterogeneity of chemical compositions present in the individual OM types. Therefore, other analytical techniques...
Lake Powell retains most of the phosphorus that it receives, leading to downstream phosphorus limitation. These data were compiled to examine controls on phosphorus cycling below Lake Powell in the Colorado River and from storm inputs from the Paria River. Objectives of our study were to determine how several forms of phosphorus, both organic and inorganic, were cycled under varying dissolved oxygen concentrations and pH, reflecting the range of values observed in the river over the years. These data represent nitrogen, phosphorus, calcium, and carbon concentrations, water quality parameters (pH, dissolved oxygen, temperature), sediment composition, total protein, and extracellular enzyme activity (alkaline phosphatase)....
These data were compiled to demonstrate new predictive mapping approaches and provide comprehensive gridded 30-meter resolution soil property maps for the Colorado River Basin above Hoover Dam. Random forest models related environmental raster layers representing soil forming factors with field samples to render predictive maps that interpolate between sample locations. Maps represented soil pH, texture fractions (sand, silt clay, fine sand, very fine sand), rock, electrical conductivity (ec), gypsum, CaCO3, sodium adsorption ratio (sar), available water capacity (awc), bulk density (dbovendry), erodibility (kwfact), and organic matter (om) at 7 depths (0, 5, 15, 30, 60, 100, and 200 cm) as well as depth to restrictive...
These data were compiled to demonstrate new predictive mapping approaches and provide comprehensive gridded 30-meter resolution soil property maps for the Colorado River Basin above Hoover Dam. Random forest models related environmental raster layers representing soil forming factors with field samples to render predictive maps that interpolate between sample locations. Maps represented soil pH, texture fractions (sand, silt clay, fine sand, very fine sand), rock, electrical conductivity (ec), gypsum, CaCO3, sodium adsorption ratio (sar), available water capacity (awc), bulk density (dbovendry), erodibility (kwfact), and organic matter (om) at 7 depths (0, 5, 15, 30, 60, 100, and 200 cm) as well as depth to restrictive...
This data set contains decomposition rates for litter of Salicornia pacifica, Distichlis spicata, and Deschampsia cespitosa buried at 7 tidal marsh sites in 2015. Sediment organic matter values were collected at a subset of sites. These data support the following publication: Janousek, C.N., Buffington, K.J., Guntenspergen, G.R. et al. Ecosystems (2017). doi:10.1007/s10021-017-0111-6. http://link.springer.com/article/10.1007/s10021-017-0111-6
Categories: Data;
Types: Citation;
Tags: Deschampsia cespitosa,
Distichlis spicata,
Pacific coast,
Salicornia pacifica,
carbon cycling,
This data table contains mean decomposition rates and mean carbon:nitrogen ratios for different litter types buried in 7 marshes during 2015. Note that C:N data are repeated for low and high marsh areas at each site in the table. These data support the following publication: Janousek, C.N., Buffington, K.J., Guntenspergen, G.R. et al. Ecosystems (2017). doi:10.1007/s10021-017-0111-6. http://link.springer.com/article/10.1007/s10021-017-0111-6
Categories: Data;
Types: Citation;
Tags: Deschampsia cespitosa,
Distichlis spicata,
Pacific coast,
Salicornia pacifica,
carbon cycling,
These data were compiled to demonstrate new predictive mapping approaches and provide comprehensive gridded 30-meter resolution soil property maps for the Colorado River Basin above Hoover Dam. Random forest models related environmental raster layers representing soil forming factors with field samples to render predictive maps that interpolate between sample locations. Maps represented soil pH, texture fractions (sand, silt clay, fine sand, very fine sand), rock, electrical conductivity (ec), gypsum, CaCO3, sodium adsorption ratio (sar), available water capacity (awc), bulk density (dbovendry), erodibility (kwfact), and organic matter (om) at 7 depths (0, 5, 15, 30, 60, 100, and 200 cm) as well as depth to restrictive...
Research examining organic-matter hosted porosity has significantly increased during the last ten years due to greater focus on understanding hydrocarbon migration and storage in source-rock reservoirs, and technological advances in scanning electron microscopy (SEM) capabilities. The examination of nanometer-scale organic-matter hosted porosity by SEM requires the preparation of exceptionally flat geologic samples beyond the abilities of traditional mechanical polishing which can deform or otherwise obscure organic surfaces. To meet this demand, broad ion beam (BIB) milling was introduced as a sample preparation technique for SEM petrographic analysis of geologic samples. But like with any sample preparation technique,...
Categories: Data;
Tags: Colorado,
Energy Resources,
England,
Geochemistry,
USGS Science Data Catalog (SDC),
This data table contains results for the 2014 mesocosm tests of inundation effects on decomposition. These data support the following publication: Janousek, C.N., Buffington, K.J., Guntenspergen, G.R. et al. Ecosystems (2017). doi:10.1007/s10021-017-0111-6. http://link.springer.com/article/10.1007/s10021-017-0111-6
Categories: Data;
Types: Citation;
Tags: Deschampsia cespitosa,
Distichlis spicata,
Pacific coast,
Salicornia pacifica,
carbon cycling,
Presented by Don Spalinger & Nathan WolfThis seminar focuses on our concepts of regulation of nutrient flows through tundra ecosystems and the effect that climate (or weather) has on these processes. Nutrient flow and climate, in turn, should regulate plant phenology and production, and thus caribou behavior and nutrition. We will present some ideas for assessing the landscape patterns of these processes and monitoring their impacts. Finally, we will provide examples of such assessment and monitoring processes from our work in Western Alaska over the past two years.​
Categories: Data;
Tags: ALPINE/TUNDRA,
ALPINE/TUNDRA,
CARBON,
CARBON,
CARBON CYCLE/CARBON BUDGET MODELS,
This data table contains summary data for temperature time series in near-surface sediments in high and low tidal marsh at 7 sites during 2015. These data support the following publication: Janousek, C.N., Buffington, K.J., Guntenspergen, G.R. et al. Ecosystems (2017). doi:10.1007/s10021-017-0111-6. http://link.springer.com/article/10.1007/s10021-017-0111-6
Categories: Data;
Types: Citation;
Tags: Deschampsia cespitosa,
Distichlis spicata,
Pacific coast,
Salicornia pacifica,
carbon cycling,
This table contains data on dry mass remaining in a subset of Salicornia pacifica and Deschampsia cespitosa litter bags removed over a series of time points spanning 6 months. These data support the following publication: Janousek, C.N., Buffington, K.J., Guntenspergen, G.R. et al. Ecosystems (2017). doi:10.1007/s10021-017-0111-6. http://link.springer.com/article/10.1007/s10021-017-0111-6
Categories: Data;
Types: Citation;
Tags: Deschampsia cespitosa,
Distichlis spicata,
Pacific coast,
Salicornia pacifica,
carbon cycling,
Here we report optical data collected as part of a collaborative study between USGS Pennsylvania Water Science Center, Pennsylvania Department of Environmental Protection and Water Mission Area Proxies Project. The optical measurements reported here were collected to aide in the characterization of water sources and mixtures and establish proxies (surrogates) for per- and poly-fluorinated alkyl substances within the Neshaminy Creek basin. Data are compiled into three tables: 1) full fluorescence spectra in vectorized format, 2) full absorbance spectra, and 3) summary file of commonly extracted optical indicators and field-based sensor arrays.
Categories: Data;
Tags: California,
California Water Science Center,
Environmental Health,
Geochemistry,
Organic Matter Research Lab,
The tundra biome is the dominant terrestrial ecosystem of the circumpolar north, and its fate in a rapidly changing climate is of high scientific and socioeconomic concern. One of those concerns is that the majority of caribou herds throughout the circumpolar north are declining, perhaps as a result of climate change. The principal objective of this research is to reveal the connections between soil nutrient cycling, forage quality and caribou habitat selection. This framework is underpinned by the concept that tundra ecosystem productivity is ultimately driven by the thermodynamics of the system induced by climate.
Categories: Data,
Publication;
Types: Citation;
Tags: ALPINE/TUNDRA,
ALPINE/TUNDRA,
CARBON,
CARBON,
CARBON CYCLE/CARBON BUDGET MODELS,
These data were compiled to demonstrate new predictive mapping approaches and provide comprehensive gridded 30-meter resolution soil property maps for the Colorado River Basin above Hoover Dam. Random forest models related environmental raster layers representing soil forming factors with field samples to render predictive maps that interpolate between sample locations. Maps represented soil pH, texture fractions (sand, silt clay, fine sand, very fine sand), rock, electrical conductivity (ec), gypsum, CaCO3, sodium adsorption ratio (sar), available water capacity (awc), bulk density (dbovendry), erodibility (kwfact), and organic matter (om) at 7 depths (0, 5, 15, 30, 60, 100, and 200 cm) as well as depth to restrictive...
These data were compiled to demonstrate new predictive mapping approaches and provide comprehensive gridded 30-meter resolution soil property maps for the Colorado River Basin above Hoover Dam. Random forest models related environmental raster layers representing soil forming factors with field samples to render predictive maps that interpolate between sample locations. Maps represented soil pH, texture fractions (sand, silt clay, fine sand, very fine sand), rock, electrical conductivity (ec), gypsum, CaCO3, sodium adsorption ratio (sar), available water capacity (awc), bulk density (dbovendry), erodibility (kwfact), and organic matter (om) at 7 depths (0, 5, 15, 30, 60, 100, and 200 cm) as well as depth to restrictive...
The use of field-deployable fluorescence sensors to better understand dissolved organic matter concentrations and composition has grown immensely in recent years. Applications of these sensors to critical monitoring efforts have also grown to encompass post-fire monitoring, wastewater tracking, and use as a proxy for various contaminants. Despite the growth, it is well known that these sensors are subject to various interferences and require corrections for temperature, turbidity, and concentration effects. Although temperature corrections are widely applicable across sensors, the turbidity and concentration corrections can be site-specific and/or sensor-specific. The corrections can even be subject to changes in...
Categories: Data;
Tags: DOC,
USGS California Water Science Center,
USGS Science Data Catalog (SDC),
Water Quality,
biota,
These data were compiled to demonstrate new predictive mapping approaches and provide comprehensive gridded 30-meter resolution soil property maps for the Colorado River Basin above Hoover Dam. Random forest models related environmental raster layers representing soil forming factors with field samples to render predictive maps that interpolate between sample locations. Maps represented soil pH, texture fractions (sand, silt clay, fine sand, very fine sand), rock, electrical conductivity (ec), gypsum, CaCO3, sodium adsorption ratio (sar), available water capacity (awc), bulk density (dbovendry), erodibility (kwfact), and organic matter (om) at 7 depths (0, 5, 15, 30, 60, 100, and 200 cm) as well as depth to restrictive...
The nanoscale molecular composition of kerogen is a challenging parameter to characterize given the chemical and structural complexity exhibited by this important biopolymer. However, kerogen composition will strongly impact its reactivity and so is a critical parameter to understand petroleum generation processes during kerogen catagenesis. The recent advent of tip-enhanced analytical methods, such as atomic force microscopy-based infrared spectroscopy (AFM-IR), has allowed for the major compositional features of kerogen to be elucidated at spatial resolutions at or below 50 nm. Here we apply AFM-IR to examine inertinite, an important kerogen maceral type, from an immature Eagle Ford Shale sample. Our data show...
Categories: Data;
Tags: Atomic force microscopy-based infrared spectroscopy (AFM-IR),
Energy Resources,
Geochemistry,
Organic matter,
Shale,
Solid bitumen is a petrographically-defined secondary organic matter residue produced during petroleum generation and subsequent oil transformation. The presence of solid bitumen impacts many shale reservoir properties including porosity, permeability, and hydrocarbon generation and storage, amongst others. Furthermore, solid bitumen reflectance is an important parameter for assessing the thermal maturity of formations with little to no vitrinite. While the molecular composition of solid bitumen will strongly impact associated parameters such as the development of organic matter porosity, hydrocarbon generation, and optical reflectance, assessing the molecular composition of solid bitumen in situ within shale reservoirs...
Categories: Data;
Tags: Energy Resources,
Geochemistry,
Oil and gas resources,
Organic matter,
Shale,
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