نتایج جستجو برای: burial diagenesis
تعداد نتایج: 6420 فیلتر نتایج به سال:
Marine carbonates, precipitating from seawater through inorganic geochemical and biogeochemical processes, are considered to have recorded the signatures reflecting marine environmental conditions during their formation. However, they susceptible post-depositional diagenetic alteration. The redox chemical composition of fluid may be different those overlying seawater. Therefore, assessing wheth...
The speciation of iron in sediments and sedimentary rocks is a widely used proxy for the chemistry oxidation state ancient water bodies. Specifically, fraction reactive out total (Fe HR /Fe T ) pyrite pool PYR are thought to constrain presence sulfide column, respectively. This approach was developed tested against modern core-top sediments, but application requires consideration effects diagen...
The Lower Cretaceous Tuxen (lower Hauterivian – upper Barremian) and Sola (upper Barremian Albian) Formations in the Danish Central Graben (North Sea) constitute one of oldest chalk successions recorded globally, but have received little attention with regards to sedimentary facies depositional processes. This study presents first comprehensive carbonate analysis succession, retrieved from seve...
Snow affects the nutritional ecology of northern ungulates during winter through burial of important winter forages. We used nonlinear regression analyses to model snow-burial dynamics of blueberry (Vaccinium spp.) browse biomass, a key winter food item of Sitka black-tailed deer (Odocoileus hemionus sitchensis) in southeastern Alaska, USA. During November 2003–March 2004 we collected data from...
Among many disposal options of animal carcasses due to animal diseases including foot-and-mouth disease (FMD) and avian influenza (AI), on-farm burial has been the most frequently used one in Korea. Animal carcasses generate contaminants such as ammonium-N and chloride. This study aimed at testing biochar (BC) as a permeable reactive barrier (PRB) material in combination with fast growing tree ...
Previous retrospective studies report a core body temperature cooling rate of 3 degrees C/h during avalanche burial. Hypercapnia occurs during avalanche burial secondary to rebreathing expired air, and the effect of hypercapnia on hypothermia during avalanche burial is unknown. The objective of this study was to determine the core temperature cooling rate during snow burial under normocapnic an...
The carbon burial in vegetated sediments, ignored in past assessments of carbon burial in the ocean, was evaluated using a bottom-up approach derived from upscaling a compilation of published individual estimates of carbon burial in vegetated habitats (seagrass meadows, salt marshes and mangrove forests) to the global level and a top-down approach derived from considerations of global sediment ...
Nitrogen (N) uptake in streams is an important ecosystem service that reduces nutrient loading to downstream ecosystems. Here we synthesize studies that investigated the effects of urban stream burial on N-uptake in two metropolitan areas and use simulation modeling to scale our measurements to the broader watershed scale. We report that nitrate travels on average 18 times farther downstream in...
This paper presents a mineralogical and chemical investigation of shale deposits from the U.S. Gulf coast in order to document the mechanisms and reactions involved in the diagenetic conversion of smectite into illite. Cuttings from the 1,250 to 5,500 m stratigraphic interval of a well were sorted by grain size and analzyed by x-ray diffraction to assess chemical and mineralogical trends with d...
ABSTRACT Phanerozoic limestones are composed of low-Mg calcite microcrystals (i.e., micrite) that typically measure between 1 and 9 μm in diameter. These microcrystals, which host most the microporosity subsurface reservoirs, characterized by a variety microtextures. Despite overwhelming consensus diagenetic, origin various textures is widely debated. The commonly reported texture polyhedral ro...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید