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Sciences of Igneous and Volcanic Processes

1. The paradigm of melt-dominated, long-lived magma chambers has been questioned recently, and instead it seems that transcrustal magmatic systems dominated by crystal mush are more likely. Describe and discuss the evidence that has led to this paradigm shift. Magma chambers are large pool of melt rock beneath the surface of earth. It has been believing for a long time that the magma chambers were magma filled reservoirs Where the melting evolution is regulated by removing the crystal settling or crystallizing along the walls of the chamber. The traditional paradigm on melt dominated long-lived magma chamber has been changing with the new evidence. Aggregating evidence from geophysical, geochemical, petrological, volcanological and geological observation is demonstrating new views of the classic magma chamber paradigm (Cashman et al., 2017). First thermal models of crustal magmatism shows that is difficult to generate and then sustain large bodies of magma with 40% of melt in the shallow crust. Volcanic eruptions with poor crystal magma demonstrate the presence of such bodies, but thermal models and geochronological and geochemical information require this to be a comparatively transitory physical state (Cashman et al., 2017). Secondly, studies in igneous petrology rocks shows a level of geochemical and textural complexity that cannot the related with the simple precipitation from a melt, but by a physical and chemical interaction of crystal residue with melt over long time periods of time in a thermally fluctuating mush environment. Furthermore, intrusive bodies originated from small laccoliths to large batholiths seems to have formed via amalgamation of many smaller and interacting pulses over more than 100 000 years. Evidence of famous volcanic eruptions suggested that disparate melt-rich lens or pockets the merge moments before or during the eruptions. Other than a gigantic chamber of pre-eruptive magma (Cashman et al., 2017). Finally, geophysical techniques, such as seismology, gravity and magnetotellurics, were noticeably ineffective in finding large melt-dominated areas in the shallow crust beneath most volcanoes of the arc. In places where large crustal geophysical anomalies exist, such as in the Alitplano -Puna in Bolivia, these more like large of partial molten body of rocks than liquid rich chambers (Cashman et al., 2017). Figure.1-Transcrustal magmatic system, where melt processing in the profound crust generates melts that are transported to mid- and ultimately upper crustal concentrations. The potential for temporary vertical connectivity in this scheme introduces the option of consecutive melt lens destabilization. The transcrustal magmatic system is dominated by crystal mush that are by located at or above the solidus and are equivalent to partially molten rock. Muses have their rheology controlled by deformation of crystalline framework that makes not eruptible in is totality. For the reason the mush behavior is sensitive to the absolute melt fraction. This is only real bellow 0.07, which establishes the transition of the fluid connectivity bellow which improves the strength of the crystal-melt aggregate with reducing melt fraction. as seen in Figure 2. However, mush fragments may erupt as glomerocrysts (crystals clots), cumulate nodules or restite. By contrast, eruptible magma is presented as crystal melting suspension (with or without exsolved volatiles). The transition from magma to mush takes places within a limited range of crystal content where the magnitude of bulk viscosity increases, and the crystal-melt suspension develops strongly non- Newtonian properties (Fig.1). The rheological transition occurs around 60%. By explaining the TMCS is possible to explain processes that represents internal controls on volcanic eruption such as: (1) relate physical processes of crystal-melt-fluid segregation to magmatic differentiation, (2) anticipate interactions between melts and fluids generated and stored at different depths, and (3) Determine the physical processes by which magma and related fluids migrate through the crust, accumulate in shallow chambers, and then erupt. Fig­ (2) Changes in magma (orange) and mush (gray) rheology as a function of the amount of fractional particles. The blue curve is calculated assuming a maximum packing fraction of 0.6 and a classic Roscoe-Einstein formula (10). Red curve uses the (12) formulation. Inset shows changes in mush intensity as a function of particle volume fraction; green dashed curve is experimental data using Western granite; purple dashed curve is experimental data using Delegate aplite. The idea of a magmatic system extends beneath upper crust is proven by geochemical cases for magma accumulation and processing in the deep crust. Most recent thermal and physical models claim an extensive igneous differentiation in the deeper parts of the crust. The melt storage in the lower crust may partially solve a problem in studies of magmatic systems because of the inability of geophysical imaging techniques to identify in large volumes of melt in the subsurface. These volcanic systems are underlain by electrically conduct zones of low velocity that are hotter than the surrounding crust and probably contain melt, for example: tomographic studies in the Yellowstone caldera in the USA identified a 10,000 km3 low-velocity body at 5-6o 17km depth, which underlain by an even larger lower crustal anomaly (Cashman et al., 2017). The geometry of melt distribution in lower and mid-crustal reservoirs is not well established. Melt fraction estimation based on tomography and magneto-telluric images have a resolution that are typically no better than 1km, therefore, melt regions are so small that cannon be detected. But a reasonable concept tells that the melt is heterogeneously distributed in the lower crust and includes microscale melt distributed along grain boundaries, while mesoscale differences in melt concentration are caused by compaction and large-scale vertically oriented melt-rich lens. The struggle of geophysical methods to identify rich bodies of melts in the upper crust suggests that large volumes of melt in upper crustal may be ephemeral. In the mid-ocean ridge, the melting lens is recognized as thin and sill as in form. In arc environment, the melt accumulations appear to be limited to the mid crust, where they feed multiple volcanoes. It was observed a low velocity zones are typically narrow a vertically elongate, averaged melt estimates are less than 10% and exsolved volatiles may be important at shallow levels in the middle of mid crust and individual volcanoes. Magma storage conditions can be inferred from the composition material’s compositions and textures (lava and pyroclasts). By using phase equilibria experiments, phase compositions and ratios can be matched to pre-eruptive magma storage circumstances, and bulk magma compositions are commonly used track magma evolution by crystal fractionation or assimilation Evidence for extensive entrainment of crystals all over the spatial extend of the magmatic system suggest that these methods not provide enough information describe most of the systems. The diversity of crystal “cargo” contained in the plagioclase, displayed the crystallization history is preserved in a complex compositional zoning that is show as shade gray in backscattered electron as shown at figure 2 (Cashman et al., 2017). The crystal core resided in a cooler but deeper part of the magmatic system before being transported by melt hotter to a shallow to temporary storage region and then to the earth’s surface. This information demonstrates that various crystals in a sample or even various zones inside a crystal, developed from isotopically distinct melts. It is difficult to visualize such little scale isotopic heterogeneity existing inside an enormous and continuous body of melt. Further insight into the nature of magmatic storage systems can be found in measured time scales of magmatic differentiation, crystal growth, and (pre-eruptive) residence time in the transporting melt. Dating zircon crystals helps estimating time scales of magma differentiation, which are sufficiently resilient to be recycled between individual magma batches. Looking at that, zircon dating suggested that differentiation time scales of 103 approximately 105 which is contrary to the idea of magma accumulation in the upper crust before volcanic eruption which is between 1 to 1000 years (Cashman et al., 2017). Fig. 2- Complex crystal history in magma from the volcano Mount St. Helens, USA. (A) Backscatter scanning electron microscope picture (inset) and isal distribution of plagioclase structure (as X An) in a single crystal from the eruption of Mount St. Helens in December 1980. The key structure (mode ~An 45) is significantly more advanced than that of the wide internal border area (mode~An 65) (Cashman et al., 2017). 2. Spreading rate imparts a first order control on the structure of the ocean crust. Describe the characteristics of slow spreading ridges and how these differ to ocean crust formed at a fast spreading rate. Include reference to morphology, structure, geophysical observations and geochemical variability. The Mid-Ocean Ridge is seafloor system of mountain formed of tectonic plates. Mid-ocean ridges are one of the most important geological processes that form the earth. They produce more than two-thirds of the world’s crust, are the main means of geochemical differentiation on Earth, and supply vast hydrothermal systems that affect ocean water chemistry and maintain vast ecosystems. (Steele et al, 2008). Around the global ridge system, new lithosphere is created at rates over a factor of ten. Such variability causes massive variations within the nature of the magmatic, tectonic and hydrothermal processes. Seafloor spreading is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge. The morphology of mid-ocean ridge is determined by the rate of spreading floor. There are quite distinct morphologies in the world ridge system that represents different constructional processes. Studying the velocity of spreading rates, ocean ridges have been divided into fast-, intermediate-, and slow-spreading, each with different morphologic characteristics. The changes caused by the spreading rate still on debate because occur too long for direct observations. The fast spreading ridges are characterized by a continuous volcano of axial shield that is affected by transforming faults and places where the spreading center experiences en echelon and overlapping offsets (Macdonald and Fox, 1983). Results from recent Seabream bathymetric information suggests segments of the East Pacific Ridge have 100 km of axial shield volcano perfectly continuous, usually with a narrow summit graben less than 500 m wide. In the other hand, the slow spreading ridge have a discontinuous string of volcanoes of varying height and morphology in the axial in the axial nonvolcanic zone. Only the gross tectonics structure of the rift valley shows transform to transform continuity. This distinction in morphology is compatible, with an underlying axial magma chamber which is relatively continuous between ridges offsets at fast spreading rates (Mutter and Karson, 1992) . The topography across fast spreading ridges is more subtle than the topography of slow spreading ridges. Researchers believe that the heat of magma is important on the morphology of the ridge. The slow spreading ridges has a slow rate supply of magma that is not enough to create large fissure eruption the oceanic plate cools, resulting of the subduction the crest of the ridge. In contrast, the rate of slow spreading ridges magma is considerable higher, in which keeps the plates warmer and the crest of the rise does no subside. Furthermore, the slow spreading ridges has hundreds of seamounts form in the rift along the crest of the ridge, different from volcanism at fast spreading ridges that is subaerial fissure erupts connected with volcanic rift zones (Kearey et al,.2009. The slow spreading ridge has a rough and faulted topography created in the rift valley is largely preserved in the older ocean basin, while the fast spreading rates there are not rift valley but is observed a triangular shaped axial high with a topography relatively smooth with a fine scale horst and graben structure (Mutter and Karson, 1992) . Figure.3 -Bathymetric ocean ridge profiles at fast and slow spreading rates. EPR, East Pacific Rise ; MAR, Mid Atlantic Ridge. Neovolcanic area bracketed by Vs, area of fissure by Fs, extent of active fault. Models to explain the formation of oceanic lithosphere suggested that is required a magma chamber beneath the ridge axis where the magma erupts to created lava flows and dykes of layers 2. Then, the magma inside the chamber solidifies to format most of a third oceanic layer 3. Detailed seismic surveys at ridge crests using refraction, reflection, and tomographic techniques has been used to seek the presence of such magma chamber. Survey carried at fast spreading east pacific rise show a region of low seismic velocities in the lower crust, 4-8 km wide and evidence for the top of a magma chamber at varying depths. Some observation suggests an invert correlation between magma chamber depth and spreading rate, because the magma chamber is less at 14°S compared to 9°N on the East Pacific Rise. This came across when in experiment the volume in which the P-wave velocity is less than 3 kms-1 is a melt lens and where the velocity is greater than 5kms-1 is regarded as solid, as shown in figure 4. In contrast, most of seismic study in slow fast spreading Mid Ocean Ridges recognize low velocity zones but lacks evidence of melt or magma chambers. However, Calvert (1995) made a study and by isolating reflections from a data of Detrick et al. (1990) presumed magma chamber at a depth of 1.2 km and with of 4 km, but other studies also suggest that the process of crustal accretions in slows-spreading ridges is similar to the fast spreading ridges but the magma chambers involved are short-lived instead of a steady state. A melt lens grows in fast-spreading ridges where there is a sufficiently high rate of magma supply for it to continue at the top of the mush zone. This lens may stretch across the ridge crest for tens of kilometres but is only 1–2 km broad and tens or hundreds of meters thick. Slow-spreading ridges are presumed to have limited magma supply for a melt lens to develop and that eruptions only occurs when there are periodic influxes of magma from the mantle (Rona et al., 2013). Figure.4 – Variation of P wave velocity in the oceanic crust at the East Pacific Rise crest at 9 ° 30′N, deduced from extended spread (ESP) and prevalent seismic depth point profiling. Shaded area shows a region with a high proportion of melting. An interpretation of velocities in terms of rock units and an indication of the extent of the area of anomalously low seismic velocities (LVZ) The composition in the lithology and chemistry of basalts generated at mid ocean ridges shows a link with the spreading rate (Flower; 1981, The difference is believed to be related to the fraction environment after partial melting. Slow spreading rides system are characterized by a complex magma chamber where the widespread accumulation of calcic plagioclase, the presence of phenocryst liquid reaction morphologies and pyroxene dominated fractionation extracts. These situations are consistent with the fractionation of different pressure of short-lived chambers. This finding is equivalent to the pattern earth element in basalts sampled from the Mid-Atlantic Ridge. The basalt of the slow spreading ridges has a lower sodium and higher iron contents that usual Mid Ocean ridge basalt. Moreover, in the Fast-spreading ridges, however, suggest low-pressure basalt fractionation trends to iron-rich compositions with little plagioclase accumulation or crystal–liquid interaction. This is consistent with the magma chamber being a stable and steady state feature (Rona et al., 2013). Transform faults and other axial offsets such as propagating rifts disturb the thermal structure of mid-ocean ridge segments by juxtaposition of a cold, rigid boundary with the spreading axis. The age contrast of the crustal across the transform fault dictates the degree of the thermal disturbance. The spaces between offsets are so close that becomes a problem to main magma chamber at any spreading rate. Near a transform fault the oceanic crust accreted may become thinner in consequence to a reduced volcanic budget. In addition, sear stress which are transmitted from the transform fault into the spreading centre domain, deforms the crust. Based in the GEBCO bathymetric charts In the North Atlantic the average transform fault spacing is 50 km and, in the Pacific, the average spacing of the transform fault is around 90 km (Rona et al., 2013). The disrupting influences of transform fault in spreading centres is greater at slow spreading centres than in fast as a result of a spreading rate dependence on their spacing. Actually, In every segment of Mid Atlantic ridge is influenced by the transform fault edge effect s along its entire length because of the viscous head-loss, lateral heat flow and propagations of shear stresses into the spreading centre domain. the spreading rates also dictates the style of deformations of transform offsets. Fast spreading rates have two axial offsets that are very rare in the slow ridges propagating rifts (spreading rifts that propagates along strike though plates, creating a V-shaped wake in their path) and Overlapping spreading centres (Rona et al., 2013). There is considerable evidence of propagating rifts at fast spreading centres but not so much in the slow spreading Atlantic. However, stable cells that maintain their integrity for tens millions of years and persists for transforms offsets of only 20 km and for periods when asymmetric spreading reduces the transform to near zero. One of the hypostases raised is that in the fast spreading rate the isotherms are shallower than at slow spreading rate, therefore, the transformer offsets the rigid lithosphere will be thinner and more easily fracture across the fast spreading ridges. While the slow rates, the rigid lithosphere is thick enough to the point that even at the offsets transform faults the rift propagation is impeded (Rona et al., 2013). Figure 5- Interpretive models of magma chambers beneath a fast (a) and slow (b) spreading ridge (modified from Sinton
SOC 450 SU Threats to The Global Environment Technology Assessment Presentation.

Presentation on Threats to the Global EnvironmentOverviewCongratulations! The members of the United Nations found great value in the two analyses you provided. They are now asking you to develop a PowerPoint presentation that addresses four of the most critical threats to the global environment. Critical threats include:Energy sources.Globalization.Lack of educational opportunities.Inappropriate use of technology.Civil war.Poor health of entire population.Cultural taboos.Climate change.InstructionsStep I. Narrow the List from Eight to the Four Most Critical ThreatsTo complete this step, complete the following tasks in order:Review research on each of the eight threats.Determine what you believe to be the current and potential future impacts of each threat on the global environment.Choose the four threats that you see as the most critical by considering which pose the greatest or most immediate risk.Step II. Create the PowerPoint PresentationThe completed version of this presentation will include a minimum of 16 slides. Your audience consists of the United Nations General Assembly.PPT Content and StructureTitle Slide: Include your name, course title, current date, and the name of your instructor.Introduction Slide: List the four threats you chose, and in the Notes section offer a brief narrative justifying these choicesBody Slides: The slide content is listed in the outline below. For each body slide you develop, please include a paragraph in the Notes section explaining how the details you have provided in the slide are pertinent to the United Nations’ discussion on selecting and prioritizing goals.For your first threat (this is the threat you consider to be the greatest risk/highest priority):One slide on a brief history and assessment of the threat.One slide on the countries most affected by the threat, and how those countries are affected (please give examples).One slide on the effects of this threat on the world population as a whole.One slide including a chart, graph, or compelling visual that relates to the content you present in body slides a–c.For your second threat (this is the threat you consider to be the second greatest risk/second highest priority):One slide on a brief history and assessment of the threat.One slide on the countries most affected by the threat, and how those countries are affected (please give examples).One slide on the effects of this threat on the world population as a whole.One slide including a chart, graph, or compelling visual that relates to the content you present in body slides a–c.For your third threat (this is the threat you consider to be the third greatest threat/highest priority):One slide on a brief history and assessment of the threat.One slide on the countries most affected by the threat, and how those countries are affected (please give examples).One slide on the effects of this threat on the world population as a whole.One slide including a chart, graph, or compelling visual that relates to the content you present in body slides a–c.For your fourth threat (this is the threat you consider to be the fourth greatest threat/highest priority):One slide on a brief history and assessment of the threat.One slide on the countries most affected by the threat, and how those countries are affected (please give examples).One slide on the effects of this threat on the world population as a whole.One slide including a chart, graph, or compelling visual that relates to the content you present in body slides a–c.Conclusion Slide: Summarize your findings for the Assembly.(Optional) Reference Slide: You can include full-text citations in the Notes section of each slide or provide a reference slide at the end of the presentation with the full citations of your sources.Note:Please discuss the threats in order of priority as described above, so the threat you consider the greatest should be discussed first in the presentation and so on.Please use at least five credible sources to back up your discussion.The body slides should summarize your key takeaways, whereas the notes section of each body slide should discuss the evidence and the details that support your takeaways. The content in both the notes and body sections requires citations and sources.
SOC 450 SU Threats to The Global Environment Technology Assessment Presentation

Importance of hand washing

Share this: Facebook Twitter Reddit LinkedIn WhatsApp One of the main causes of transmission of infection is contaminated hands. Routine hand washing is one of the most effective measures used to prevent or control this transmission of infectious diseases. To ensure its effectiveness however, specific techniques needs to be carried out. The following are some of the topics which will be addressed: The importance of hand washing Proper hand washing techniques Short-term alternatives to hand washing Promoting good hand hygiene The Importance of Hand washing Hand washing is an important technique in removing or reducing the number of microorganisms from the hands. This in turn will reduce the potential transmission of these microorganisms directly to others or to surfaces where they can be picked up by others. Washing of ones hands will also decreases the risk of transmission of infectious agents to self. Hand washing is especially important among healthcare workers. “Contaminated hands of health care workers are a primary source of infection transmission in health care setting” (Perry and Potter, 2009, p.655). Of equal importance is also hand washing among young children. In this instance it can help prevent common illnesses such as the flu and help them stay healthier. Some of the most common diseases that can be spread through hand to hand contact are infectious diarrhea, the flu, the common cold and also some intestinal disorders. This can affect people who are more vulnerable to infectious diseases such as those with reduced defenses including the elderly or even very young children. Other consequences of not washing the hands or improper washing of hands includes food related illnesses for example E.coli infection or salmonella. These conditions can also lead to intestinal problems which can cause vomiting and diarrhea. Effective Hand washing Techniques Hands should be: washed under running water, using a single dose of liquid soap or antiseptic; vigorously rubbed together for 10-15 seconds; rinsed thoroughly under running water and dried with a disposable paper towel (Gould D.Drey, 2008). Hand washing technique may sound simple, but to be effective it must be done correctly. Gould D.Drey (2008) made reference to Feldman’s criteria which was developed to evaluate hand hygiene technique. Some of the criteria listed in the article were; whether soap bubbles appeared, the absence of environmental contamination by avoiding splashing and coverage of the hand surfaces. Another evaluation technique mentioned by Gould D. Drey (2008) was done by Taylor who according to the article, nurses were persuaded to perform their hand washing routine with their eyes shut. A dye was then used to show the parts of the hand that had not received contact. In this instance if parts of the hand did not receive contact during washing this was a sign of inadequate hand washing. Short-Term Alternatives to Hand washing “In addition to hand washing with antiseptic products, hand disinfection also includes the use of alcohol containing waterless hand sanitizers” (Handwashing, Cover story, 2002). The article further went on to say alcohol was an effective alternative when water or towels are not readily available. The availability and convenience of hand sanitizers and antimicrobial gels can also increase compliance in hand cleansing particularly in instances where soap and water are not readily available. Promoting Good Hand Hygiene In order to promote good hand hygiene some of the reasons for being non-compliant must be addressed. Lack of time and a heavy workload were stated as barriers to hand hygiene compliance (R. Baret and J. Randle, 2008). This is mostly evident among health care workers. Some of the things that can be done to improve non-compliance includes; effective communication and education about infection control, reminders posted visually to promote good hand hygiene, conveniently located dispensing equipment with hand sanitizers, only to list a few. Practicing good hand hygiene prevents the transmission of nosocomial infections which are only acquired while in heath care facility. Not only are the health care workers to wash hands but encouraging patients and their visitors to do the same will to continue the cycle of infection control. Conclusion The practice of hand washing is no longer only a means of personal hygiene but an important measure of infection control. The incidents of transmitting infectious disease can be minimized by ensuring that hands are washed after using the restroom, before and after eating, when hands are visibly dirty or contaminated, after contact with animals or other person’s intact skin, after contact with body fluids, after contact with inanimate objects and the list is not redundant by any means. A major way to reduce the incidents of transmitting infections is to think of frequent hand washing, not to be optional but as a rule. Secondly, always keep in mind that the use of gloves does not eliminate the need to wash hands. To protect your health it is recommended you wash your hands as often as necessary. Share this: Facebook Twitter Reddit LinkedIn WhatsApp

GCU Outcome and Process Measures used for CQI Research Paper

custom essay GCU Outcome and Process Measures used for CQI Research Paper.

In a 1,000-1,250 word paper, consider the outcome and process measures that can be used for CQI. Include the following in your essay:At least two process measures that can be used for CQI.At least one outcome measure that can be used for CQI.A description of why each measure was chosen.An explanation of how data would be collected for each (how each will be measured).An explanation of how success would be determined.One or two data-driven, cost-effective solutions to this challenge.Prepare this assignment according to the guidelines found in the APA Style Guide, located in the Student Success Center. An abstract is not required.This assignment uses a rubric. Please review the rubric prior to beginning the assignment to become familiar with the expectations for successful completion.You are required to submit this assignment to LopesWrite. This benchmark assignment assesses the following programmatic competency:MSN Emphasis in Leadership in Health Care Systems6.5 Generate data-driven, cost-effective solutions to organizational challenges.
GCU Outcome and Process Measures used for CQI Research Paper

UWM Apple Inc Social Media Policy Discussion & Peer Review Worksheet

UWM Apple Inc Social Media Policy Discussion & Peer Review Worksheet.

Complete the activity below in 100-150 words.Choose one of these companies and look up its “social media policy/guidelines”–Samsung, Apple, Ford, General Motors, Tesla, H-E-B, TAMUK. Simply run a search on google using the name of the company and the terms “social media guidelines.” Then, briefly address the following questions:is the policy statement clear, specific, and comprehensive?is the statement easy to read and understand? what makes the statement easy or difficult to read?does the statement include a persuasive explanation of why the policy is necessary?is the tone of the statement positive or negative?how would you feel if you were required to abide by this policy?Break up your response into proper paragraph
UWM Apple Inc Social Media Policy Discussion & Peer Review Worksheet

mkt315 week 1 discussion 2 AND response

mkt315 week 1 discussion 2 AND response. I’m stuck on a Marketing question and need an explanation.

“Channel Participants” Please respond to the following:

Select any intermediary in the marketing channel. Discuss the duties and importance of the intermediary.
Examine the different types of facilitating agencies. Provide specific examples of the tasks that each facilitating agency may be responsible for.

AND respond to this post:
(will message it to you in a little bit)

mkt315 week 1 discussion 2 AND response