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Teichichnus
''Teichichnus'' is an ichnogenus with a distinctive form produced by the stacking of thin 'tongues' of sediment, atop one another. They are believed to be fodinichnia, with the organism adopting the habit of retracing the same route through varying heights of the sediment, which would allow it to avoid going over the same area. These 'tongues' are often quite sinuous, reflecting perhaps a more nutrient-poor environment in which the feeding animals had to cover a greater area of sediment, in order to acquire sufficient nourishment. ''Teichichnus'' is recognized as a series of tightly packed, concave-up laminae, and lacks an outside border or lining, which distinguishes ''Teichichnus'' from the ''Diplocraterion'' ichnogenus An ichnotaxon (plural ichnotaxa) is "a taxon based on the fossilized work of an organism", i.e. the non-human equivalent of an artifact. ''Ichnotaxa'' comes from the Greek ίχνος, ''ichnos'' meaning ''track'' and ταξις, ''taxis'' meaning .... Exte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trace Fossils
A trace fossil, also known as an ichnofossil (; from el, ἴχνος ''ikhnos'' "trace, track"), is a fossil record of biological activity but not the preserved remains of the plant or animal itself. Trace fossils contrast with body fossils, which are the fossilized remains of parts of organisms' bodies, usually altered by later chemical activity or mineralization. The study of such trace fossils is ichnology and is the work of ichnologists. Trace fossils may consist of impressions made on or in the substrate by an organism. For example, burrows, borings ( bioerosion), urolites (erosion caused by evacuation of liquid wastes), footprints and feeding marks and root cavities may all be trace fossils. The term in its broadest sense also includes the remains of other organic material produced by an organism; for example coprolites (fossilized droppings) or chemical markers (sedimentological structures produced by biological means; for example, the formation of stromatolites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lost Hills Oil Field
The Lost Hills Oil Field is a large oil field in the Lost Hills Range, north of the town of Lost Hills in western Kern County, California, in the United States. Production While only the 18th-largest oil field in California in size, in total remaining reserves it ranks sixth, with the equivalent of over producible reserves still in the ground, according to the California Division of Oil, Gas and Geothermal Resources (Chevron Corp., the principal operator, estimates considerably more oil in the ground). Production at Lost Hills has been increasing steadily: as of the end of 2006, it was California's second fastest-growing oil field, exceeded only by the nearby Cymric Field. The Lost Hills field also contains considerable reserves of natural gas. In 1998, one of the field's gas wells was the site of a spectacular blowout, producing a pillar of fire which burned for 14 days and was visible more than away. Setting The Lost Hills Field underlies a long, low range of southeast-t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
California
California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the most populated subnational entity in North America and the 34th most populous in the world. The Greater Los Angeles area and the San Francisco Bay Area are the nation's second and fifth most populous urban regions respectively, with the former having more than 18.7million residents and the latter having over 9.6million. Sacramento is the state's capital, while Los Angeles is the most populous city in the state and the second most populous city in the country. San Francisco is the second most densely populated major city in the country. Los Angeles County is the country's most populous, while San Bernardino County is the largest county by area in the country. California borders Oregon to the north, Nevada and Arizona to the east, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electromagnetic Spectrum
The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies. The electromagnetic spectrum covers electromagnetic waves with frequencies ranging from below one hertz to above 1025 hertz, corresponding to wavelengths from thousands of kilometers down to a fraction of the size of an atomic nucleus. This frequency range is divided into separate bands, and the electromagnetic waves within each frequency band are called by different names; beginning at the low frequency (long wavelength) end of the spectrum these are: radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays at the high-frequency (short wavelength) end. The electromagnetic waves in each of these bands have different characteristics, such as how they are produced, how they interact with matter, and their practical applications. There is no known limit for long and short wavelengths. Extre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UV Light
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the Sun. It is also produced by electric arcs and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights. Although long-wavelength ultraviolet is not considered an ionizing radiation because its photons lack the energy to ionize atoms, it can cause chemical reactions and causes many substances to glow or fluoresce. Consequently, the chemical and biological effects of UV are greater than simple heating effects, and many practical applications of UV radiation derive from its interactions with organic molecules. Short-wave ultraviolet light damages DNA and sterilizes surfaces with which it comes into contact. For ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ichnogenus
An ichnotaxon (plural ichnotaxa) is "a taxon based on the fossilized work of an organism", i.e. the non-human equivalent of an artifact. ''Ichnotaxa'' comes from the Greek ίχνος, ''ichnos'' meaning ''track'' and ταξις, ''taxis'' meaning ''ordering''.Definition o'ichno'at dictionary.com. Ichnotaxa are names used to identify and distinguish morphologically distinctive ichnofossils, more commonly known as trace fossils. They are assigned genus and species ranks by ichnologists, much like organisms in Linnaean taxonomy. These are known as ichnogenera and ichnospecies, respectively. "Ichnogenus" and "ichnospecies" are commonly abbreviated as "igen." and "isp.". The binomial names of ichnospecies and their genera are to be written in italics. Most researchers classify trace fossils only as far as the ichnogenus rank, based upon trace fossils that resemble each other in morphology but have subtle differences. Some authors have constructed detailed hierarchies up to ichnosup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sediment
Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone ( sedimentary rocks) through lithification. Sediments are most often transported by water ( fluvial processes), but also wind (aeolian processes) and glaciers. Beach sands and river channel deposits are examples of fluvial transport and deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans. Desert sand dunes and loess are examples of aeolian transport and deposition. Glacial moraine deposits and till are ice-transported sediments. Classification Sediment can be classified based on its grain size, grain s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fodinichnia
Fodinichnia (singular fodinichnion) are trace fossils formed by deposit feeders as they excavate the sediment in search of food.Allaby A & Allaby M (1999) Oxford Dictionary of Earth Sciences. They tend to have repeated patterns (e.g. '' Chondrites'') or spreites (e.g. '' Rhizocorallium''), the shape reflecting the systematic feeding strategy used by the organism as it scours the sediment. Deposit feeding often results in structures with no overlapping parts, as the deposit feeder optimises its nourishment intake by avoiding going over the same area more than once. This avoidance behavior is called phobotaxis. The shape of fodinichnia can yield evidence of the depositional environment of the sediment in which they were made. For example, a trace with highly sinuous branches may reflect nutrient-poor conditions where the organism needed to ingest more sediment in order to acquire the same amount of nutriment that a straighter branch in a nutrient-rich environment would. Reference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diplocraterion
''Diplocraterion'' is an ichnogenus describing vertical U-shaped burrows having a spreite (weblike construction) between the two limbs of the U. The spreite of an individual ''Diplocraterion'' trace can be either protrusive (between the paired tubes) or retrusive (below the paired tubes). Some ichnospecies have both types (e.g., ''Diplocraterion yoyo''). The presence/absence of funnel-shaped openings should not be used as an ichnotaxobase due to the high probability that the upper portions of the trace may have been eroded away. Observation of the orientation of ''Diplocraterion'' in the field is frequently used to determine the way up of rock strata at outcrop. There are several ichnospecies of ''Diplocraterion''. Ethology The various ichnospecies of ''Diplocraterion'' provide a good example of how ethology (animal-substrate interactions and behavior) can be interpreted from trace fossils. ''Diplocraterion'' is a classic example of equilibrichnia (equilibrium traces). Thes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
