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Hydrate Ridge
Hydrate Ridge is an accretionary thrust clathrate hydrate formation, meaning it has been made of sediment scraped off of subducting oceanic plate. It is approx. 200 m (700 ft) high, and located 100 km (62 mi) offshore of Oregon. At hydrate formations, methane is trapped in crystallized water structures. Such methane transforms into the gaseous phase and seeps into the ocean at this site, which has been a popular location of study since its discovery in 1986. Hydrate Ridge also supports a methane-driven benthic community. Significance Hydrate Ridge and other hydrate formations store methane for extended periods of time. This methane can be released back into the ocean as a result of underwater seismic activity or other sudden movements. Methane is a potent greenhouse gas, and the study of hydrate formations can lead to information about their influences on the global carbon cycle and carbon sequestration. Because it is one of the most easily accessible hydrate formations in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Hydrate Ridge
Southern Hydrate Ridge, located about 90 km offshore Oregon Coast, is an active methane seeps site located on the southern portion of Hydrate Ridge. It extends 25 km in length and 15 km across, trending north-northeast-south-southwest at the depth of approximately 800 m.Liu, & Flemings. (2006). Passing gas through the hydrate stability zone at southern Hydrate Ridge, offshore Oregon. ''Earth and Planetary Science Letters,'' ''241''(1-2), 211-226. Southern Hydrate Ridge has been the site of numerous submersible dives with the human occupied ''Alvin'' submarine, extensive visits by numerous robotic vehicles including ''the Canadian ROV ROPOS'', ''Jason (US National Deep Submersible Facility)'', and ''Tiburon'' (MBARI), and time-series geophysical studies that document changes in the subsurface distribution of methane. It is also a key site of the National Science Foundations Regional Cabled Array that is part of the Ocean Observatories Initiative (OOI), which includes eig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrate Ridge
Hydrate Ridge is an accretionary thrust clathrate hydrate formation, meaning it has been made of sediment scraped off of subducting oceanic plate. It is approx. 200 m (700 ft) high, and located 100 km (62 mi) offshore of Oregon. At hydrate formations, methane is trapped in crystallized water structures. Such methane transforms into the gaseous phase and seeps into the ocean at this site, which has been a popular location of study since its discovery in 1986. Hydrate Ridge also supports a methane-driven benthic community. Significance Hydrate Ridge and other hydrate formations store methane for extended periods of time. This methane can be released back into the ocean as a result of underwater seismic activity or other sudden movements. Methane is a potent greenhouse gas, and the study of hydrate formations can lead to information about their influences on the global carbon cycle and carbon sequestration. Because it is one of the most easily accessible hydrate formations in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climate Change
Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global temperatures is Scientific consensus on climate change, driven by human activities, especially fossil fuel burning since the Industrial Revolution. Fossil fuel use, Deforestation and climate change, deforestation, and some Greenhouse gas emissions from agriculture, agricultural and Environmental impact of concrete, industrial practices release greenhouse gases. These gases greenhouse effect, absorb some of the heat that the Earth Thermal radiation, radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary gas driving global warming, Carbon dioxide in Earth's atmosphere, has increased in concentratio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cabled Observatory
A cabled observatory is a seabed oceanographic research platform connected to land by cables that provide power and communication. Observatories are outfitted with a multitude of scientific instruments that can collect many kinds of data from the seafloor and water column. By removing the limitations of undersea power sources and sonar or RF communications, cabled observatories allow persistent study of underwater phenomena. Data from these instruments is relayed to a land station and data networks, such as Ocean Networks Canada, in real time. On-board sensors Cabled observatories have the benefit of high-power cable connections that can support a variety of instrumentation at any time. Such instrumentation can include cameras and microphones that can take high-definition audio and video, standard sensors that measure pressure, temperature, oxygen content, conductivity, turbidity, and chlorophyll-a fluorescence, and custom sensors for specialized purposes. Over 200 instruments ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocean Observatories Initiative
The Ocean Observatories Initiative (OOI) is a National Science Foundation, National Science Foundation (NSF)]Major Research Facilitycomposed of a network of science-driven Ocean observations, ocean observing platforms and sensors (ocean observatory, ocean observatories) in the Atlantic and Pacific Oceans. This networked infrastructure measures physical, chemical, geological, and biological variables from the seafloor to the sea surface and overlying atmosphere, providing an integrated data collection system on coastal, regional and global scales. OOI's goal is to deliver data and data products for a 25-year-plus time period, enabling a better understanding of ocean environments and critical ocean issues. History As early as 1987, the ocean sciences community began discussions about the science, design concepts, and engineering of ocean research observatories, leading to the formation of the International Ocean Network (ION) in 1993. The ION national committee was formed in 1995 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microorganism
A microorganism, or microbe, is an organism of microscopic scale, microscopic size, which may exist in its unicellular organism, single-celled form or as a Colony (biology)#Microbial colonies, colony of cells. The possible existence of unseen microbial life was suspected from antiquity, with an early attestation in Jain literature authored in 6th-century BC India. The scientific study of microorganisms began with their observation under the microscope in the 1670s by Anton van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s, Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera, diphtheria, and anthrax. Microorganisms are extremely diverse, representing most unicellular organisms in all three domains of life: two of the three domains, Archaea and Bacteria, only contain microorganisms. The third domain, Eukaryota, includes all multicellular o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbiosis
Symbiosis (Ancient Greek : living with, companionship < : together; and ''bíōsis'': living) is any type of a close and long-term biological interaction, between two organisms of different species. The two organisms, termed symbionts, can for example be in Mutualism (biology), mutualistic, commensalism, commensalistic, or parasitism, parasitic relationships. In 1879, Heinrich Anton de Bary defined symbiosis as "the living together of unlike organisms". The term is sometimes more exclusively used in a restricted, mutualistic sense, where both symbionts contribute to each other's subsistence. This means that they benefit each other in some way. Symbiosis can be ''obligate'' (or ''obligative''), which means that one, or both of the organisms depend on each other for survival, or ''facultative'' (optional), when they can also subsist independently. Symbiosis is also classified by physical attachment. Symbionts forming a single body live ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microbial Mat
A microbial mat is a multi-layered sheet or biofilm of microbial colonies, composed of mainly bacteria and/or archaea. Microbial mats grow at interfaces between different types of material, mostly on submerged or moist surfaces, but a few survive in deserts. A few are found as endosymbionts of animals. Although only a few centimetres thick at most, microbial mats create a wide range of internal chemical environments, and hence generally consist of layers of microorganisms that can feed on or at least tolerate the dominant chemicals at their level and which are usually of closely related species. In moist conditions mats are usually held together by slimy substances secreted by the microorganisms. In many cases some of the bacteria form tangled webs of filaments which make the mat tougher. The best known physical forms are flat mats and stubby pillars called stromatolites, but there are also spherical forms. Microbial mats are the earliest form of life on Earth for which there ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calyptogena Magnifica
''Calyptogena magnifica'' is a species of giant white clam found clustered around hydrothermal vents at abyssal depths in the Pacific Ocean. Description The systematics of the family Vesicomyidae is unclear because of the small number of specimens collected, the variability between specimens of the same species and their wide dispersal in isolated, deep water locations. The morphology of ''Calyptogena magnifica'' resembles another member of the genus, '' Calyptogena elongata'', the type locality of which is several hundred miles further north. ''C elongata'' is only known from three small specimens and the size of mature individuals is unknown. The two valves of ''Calyptogena magnifica'' are oval or slightly kidney-shaped and about two times as long as they are high. The umbones are towards the anterior end of the valve and the growth rings are most noticeable near the margins. The shell material is thick and the exterior is white and usually chalky in appearance. The periost ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Hydrate Stability Zone
Gas hydrate stability zone, abbreviated GHSZ, also referred to as methane hydrate stability zone (MHSZ) or hydrate stability zone (HSZ), refers to a zone and depth of the marine environment at which methane clathrates naturally exist in the Earth's crust. Description Gas hydrate stability primarily depends upon temperature and pressure, however other variables such as gas composition and ionic impurities in water influence stability boundaries. The existence and depth of a hydrate deposit is often indicated by the presence of a bottom-simulating reflector (BSR). A BSR is a seismic reflection indicating the lower limit of hydrate stability in sediments due to the different densities of hydrate saturated sediments, normal sediments and those containing free gas. Limits The upper and lower limits of the HSZ, as well as its thickness, depend upon the local conditions in which the hydrate occurs. The conditions for hydrate stability generally restrict natural deposits to polar regions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cold Seep
A cold seep (sometimes called a cold vent) is an area of the ocean floor where seepage of fluids rich in hydrogen sulfide, methane, and other hydrocarbons occurs, often in the form of a brine pool. ''Cold'' does not mean that the temperature of the seepage is lower than that of the surrounding sea water; on the contrary, its temperature is often slightly higher. The "cold" is relative to the very warm (at least ) conditions of a hydrothermal vent. Cold seeps constitute a biome supporting several endemic species. Cold seeps develop unique topography over time, where reactions between methane and seawater create carbonate rock formations and reefs. These reactions may also be dependent on bacterial activity. Ikaite, a hydrous calcium carbonate, can be associated with oxidizing methane at cold seeps. Types Types of cold seeps can be distinguished according to the depth, as shallow cold seeps and deep cold seeps. Cold seeps can also be distinguished in detail, as follow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismic Wave
A seismic wave is a mechanical wave of acoustic energy that travels through the Earth or another planetary body. It can result from an earthquake (or generally, a quake), volcanic eruption, magma movement, a large landslide and a large man-made explosion that produces low-frequency acoustic energy. Seismic waves are studied by seismologists, who record the waves using seismometers, hydrophones (in water), or accelerometers. Seismic waves are distinguished from seismic noise (ambient vibration), which is persistent low-amplitude vibration arising from a variety of natural and anthropogenic sources. The propagation velocity of a seismic wave depends on density and elasticity of the medium as well as the type of wave. Velocity tends to increase with depth through Earth's crust and mantle, but drops sharply going from the mantle to Earth's outer core. Earthquakes create distinct types of waves with different velocities. When recorded by a seismic observatory, their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
