Earthquake Mitigation Measures Minimizing or avoiding the risks from earthquakes involves three subject areas. First is the ability to predict their occurrence. While scientists cannot routinely predict earthquakes, this area is of growing interest and may be a key factor in reducing risks in the future. This information is used to address the third area of earthquake risk reduction-mitigation measures. Following a discussion of prediction, assessment, and mitigation, the types and sources of earthquake information are presented. Earthquake Prediction A report on an erroneous prediction of an earthquake in Lima, Peru, states:
Freshwater Fishes of Iran, Species Accounts
Abstract Sediments were collected from ten lakes and wetlands in the Upper Columbia River watershed of northeast Washington in Samples were analyzed for lead, zinc, arsenic, cadmium, copper, antimony, mercury, total organic carbon, and grain size. Lead also was analyzed in a selected sediment core for age-dating and assessment of sedimentation rates. The current study builds upon findings from a broader areal investigation of northeast Washington lakes conducted in The study reported comparatively elevated metals concentrations in lake sediments from portions of the study area generally in the vicinity of the Upper Columbia River valley.
Historical transboundary air pollution from the Trail smelter in British Columbia was identified in the study as the probable, predominant area-wide source of upland lakes sediment contamination metals in the vicinity of the Upper Columbia River valley.
Colorado Geology Photojournals A Tribute to Colorado’s Physical Past and Present Right: Trees and snow mark major Laramide uplifts in green and white while salmon pink marks the Colorado Plateau in this true-color satellite image of Colorado and surrounding states, courtesy NASA, ^Visible Earth.
Understanding Lakes Knowledge of the formation and history of a lake is important to understanding its structure. The current chemical and biological condition of a lake depends on many factors, including: In Minnesota, there are 12, lakes larger than 4 hectares 10 acres. The glaciers that covered much of the state until about 12, years ago created most Minnesota lakes. Glaciers formed lake basins by gouging holes in loose soil or soft bedrock, depositing material across stream beds, or leaving buried chunks of ice that later melted to leave lake basins Figure 1.
When these natural depressions or impoundments filled with water, they became lakes. Figure 1 After the glaciers retreated, sediments accumulated in the deeper parts of the lake. These sediments entered the lakes from tributaries and from decomposed organic material derived from both the watershed and aquatic from plants and algae.
An average Minnesota lake contains meters of such sediment in its deeper parts. Lake sediment deposits provide a record of a lake’s history. Paleolimnology is the study of lake sediments.
Lead concentration profiles in lead dated Lake Ontario sediment cores
The results were published by Juggins et al. Sediment Coring Sediment cores were collected from the deepest section of each lake using either a Glew or a Mackereth mini corer, operated from an inflatable boat. Core Preparation and Lithostratigraphy Cores were extruded in the laboratory and sectioned at 0. Basic lithostratigraphic analyses, notably dry weight, loss on ignition LOI and wet density, were performed on sub-sections of the core material.
Genus Abramis Cuvier, The bream genus comprises 4 species found in Europe, Asia Minor and the Caspian and Aral Sea basins. There are 2 species in Iran but see also Blicca and Vimba.. The genus is characterised by a strongly compressed and deep body, a scaleless keel between the vent and pelvic fins, a scaleless groove on the back in front of the dorsal fin but not behind the fin.
Davidson Abstract The effectiveness of erosion control methods is difficult to measure, hampering the development of management practices and preventing accurate assessment of the value of erosion control structures over time. Surface erosion can vary widely over an area, particularly if gully erosion is present, and the use of sediments transported in streams for quantifying erosion is hindered by the highly variable nature of fluvial sediment loads.
When a watershed drains into a lake, accumulated sediments have the potential to yield information about historic rates of sedimentation that can be used to evaluate the effectiveness of previous erosion control measures. In the present study, sediments from five natural oxbow cutoff lakes in the Mississippi River alluvial floodplain were dated using lead decay rates and bomb-pulse derived cesium with the goal of relating trends in sedimentation rate to reductions in erosion due to management practices.
It was found that the radioisotope dating methods were best used in concert with known dates for implementation of management practices. Changes in sedimentation rate over time frames as short as 12 years were detectable. Larger lakes showed smaller changes in sedimentation rate relative to smaller lakes.
Introduction This family contains by far the most species in the Iranian freshwater ichthyofauna and is divided into two files Abramis to Cyprinus here , and Garra to Vimba see both in Contents. The carp or minnow family is one of the most widespread and speciose families of fishes in the world, certainly the most speciose in fresh water and possibly the largest family of vertebrates the Gobiidae may be the first.
The family is found in North America, Eurasia and Africa.
Radiocarbon dating (also referred to as carbon dating or carbon dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon.. The method was developed in the late s by Willard Libby, who received the Nobel Prize in Chemistry for his work in It is based on the fact that radiocarbon (
But the city’s water department sees it as a potentially high-level hazard, requiring a permit and annual inspections that can be a big surprise, especially to homeowners who are inheriting an irrigation system along with a new house. As gardeners get their systems turned back on for spring, here are some things they need to know about staying within the law and maintaining a healthy water supply to their homes — and their neighbors’.
What does the city government require for operation of a sprinkler system? A permit must be obtained for the system when it is installed. At that point, the city has a record of the sprinkler system. Then, every year, the backflow preventer on the system must be checked by a registered inspector who reports the inspection to the city. Every five years, along with the inspection, the backflow valve must be rebuilt, because its parts start to deteriorate.
If a backflow preventer is not installed or isn’t working properly and there is a loss of water pressure, anything that is in the pipes and anything that is pooled around a sprinkler head — including bacteria-infested soil and pesticides — can be sucked backward into the water supply. It’s similar to drinking out of a straw: As long as you’re sucking on the straw applying pressure , the liquid goes into your mouth.
When you let up on the pressure — stop sucking — the liquid goes backward into the cup. The contaminants can travel farther than the house that has the sprinkler system — they can affect neighboring houses as well. Among common causes of a loss in water pressure are waterline breaks and fire. How many people comply with the backflow inspections?
Mass-production of Cambro-Ordovician quartz-rich sandstone as a consequence of chemical weathering of Pan-African terranes: Earth and Planetary Science Letters, , Formation and evolution of lateritic profiles in the middle Amazon basin:
News Dive into the world of science! Read these stories and narratives to learn about news items, hot topics, expeditions underway, and much more.
Paralyzed when someone asks what GIS can really do? Looking to diversify your business and services? Precision Farming — Harvesting more bushels per acre while spending less on fertilizer using precision farming and software. How to win the farm using GIS 2. Disease Control — Combating the spread of pests through by identifying critical intervention areas and efficient targeting control interventions. Swiss Alps Farming — Cultivating south-facing slopes in the Swiss Alps using aspect data because it shelters from cold and dry winds which is critical to successful crop growth.
Colorado Geology Overview
Long and Dr E. The main objective of the IPCS is to carry out and disseminate evaluations of the effects of chemicals on human health and the quality of the environment. Supporting activities include the development of epidemiological, experimental laboratory, and risk-assessment methods that could produce internationally comparable results, and the development of manpower in the field of toxicology.
At the Weggis station, the core dating yielded sediment accumulation rates of about g dry wt. m −2 y −1 with the lead method, averaged over a sediment depth of 4–20 cm; accumulation was about g dry wt. m −2 y −1 with the marker method, averaged over 0–33 cm.
These formations may have resulted from carcass burial in an anoxic environment with minimal bacteria, thus slowing decomposition. Stromatolites Lower Proterozoic Stromatolites from Bolivia , South America Stromatolites are layered accretionary structures formed in shallow water by the trapping, binding and cementation of sedimentary grains by biofilms of microorganisms , especially cyanobacteria.
While older, Archean fossil remains are presumed to be colonies of cyanobacteria , younger that is, Proterozoic fossils may be primordial forms of the eukaryote chlorophytes that is, green algae. One genus of stromatolite very common in the geologic record is Collenia. The earliest stromatolite of confirmed microbial origin dates to 2. The most widely supported explanation is that stromatolite builders fell victims to grazing creatures the Cambrian substrate revolution , implying that sufficiently complex organisms were common over 1 billion years ago.
Factors such as the chemistry of the environment may have been responsible for changes. Cyanobacteria as well as extremophile Gammaproteobacteria are thought to be largely responsible for increasing the amount of oxygen in the primeval earth’s atmosphere through their continuing photosynthesis. Cyanobacteria use water , carbon dioxide and sunlight to create their food.
CCA Environment Plan
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The rescue exercises, intended to simulate real-life medical evacuations, are the result of a joint agreement between the two maritime organizations which became official Oct. Nunan, commander, 9th Coast Guard District, said at the time the agreement was announced. Flag-fleet on the Great Lakes. It will pay dividends for our sailors and for those in other parts of the country, as the Coast Guard aviators leave the Great Lakes better trained and more proficient.
Tregurtha, one of the vessels that has participated in a handful of hoist exercises on Lake Huron this season. He says the training is very relevant to what might happen on a bulk carrier moving cargo nonstop from March to January. Participating in these exercises has also been a welcome break in the day-to-day routine for his crew of nearly two dozen mariners.
Read more and view photos at this link: The foot steamer sank abruptly on Sept. Sixteen of the 21 people on board died, along with the cows and one bull that had been loaded onto the boat from Canada’s Manitoulin Island, which lies east of Michigan’s Drummond Island in the U. The five survivors – the captain, three sailors, and the cows’ owner – drifted on a raft for 60 hours.
Dating of Sediments using Lead The naturally lead isotope Pb may be used to date aquatic sediments and peat bogs. The method is suitable for dating approximately years back. Service DHI offers dating of sediment cores by means of the Pb method and may assist with sampling in both marine and freshwater systems. The sediment samples must remain totally undisturbed during sampling to obtain the best possible dating.
Subsequently, they are cut into slices of approximately 1 cm and dried, whereupon the content of dry matter and possibly the loss on ignition are determined. The result of the dating is delivered in the form of a report stating the age of the sediment, the rate of sedimentation, the mixing depth and the mixing intensity.
Higher sedimentation rates of 4–7 mm yr −1 were found in the central part of the lake at 47 and 65 m and in the northern bay at 18 and 41 m depth. At both these sites the Pb profiles were strongly disturbed in the upper zone of the sediment cores, whereas the Cs pattern remained intact.
Raft of totora on Lake Titicaca in the island of the Sun Bolivia Uros The “Floating Islands” are small manmade islands constructed by the Uros or Uru people from layers of cut totora , a thick buoyant reed that grows abundantly in the shallows of Lake Titicaca. According to legend, the Uru people originated in the Amazon and migrated to the area of Lake Titicaca in the pre-Columbian era , where they were oppressed by the local population and were unable to secure land of their own.
There are two mountain peaks, called Pachatata Father Earth and Pachamama Mother Earth , and ancient ruins on the top of both peaks. The hillsides that rise up from the lake are terraced and planted with wheat , potatoes , and vegetables. Most of the small fields are worked by hand. Long stone fences divide the fields, and cattle and sheep graze on the hillsides.
There are no cars on the island and no hotels. Since machines are not allowed on the island, all agriculture is done by hand. A few small stores sell basic goods, and there is a health clinic and 6 schools. Electricity was produced by a generator and provided limited power a couple of hours each day, but with the rising price of the petroleum, they no longer use the generator. Most families use candles or flashlights powered by batteries or hand-cranks.