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Strain localization is central to the transition between continental rifting and seafloor spreading. In the East African Rift System (EARS), there is an emerging understanding of the link between extensional pulses and magmatic episodes. We investigate modern magmatism located within the Turkana Depression and its relationship with the distribution of extensional strain. We probe the source of magmatism at South Island volcano using bulk rock, melt inclusion and olivine geochemical data and find that the magmas are derived from sub-lithospheric sources equivalent to magmatism in the more mature sectors of the rift. The depth extent of the magmatic plumbing system of South Island is constrained using vapour saturation pressures derived from bubble-corrected H2O and CO2 concentrations in melt inclusions and the results indicate a magmatic system resembling modern axial volcanic systems observed in other parts of the EARS. The zone of focused axial magmatism that South Island represents has evolved contemporaneously with a region of focused axial faulting that has accommodated the majority of regional Holocene extension and subsidence at this latitude. We conclude that at South Island there has been a migration of magmatic and tectonic strain towards the modern zone of focused intrusion along this portion of the EARS. Supplementary material: S1–S2 image files, data table files S3–S6 and caption file S7 are available at https://doi.org/10.6084/m9.figshare.c.6026627 [ABSTRACT FROM AUTHOR]

Magma-rich rifting generally occurs over mantle plumes or rising convection cells; magma-poor rifting does not. Plumes produce up to 2 km dynamic elevation, outcompeting synrift subsidence in active and ancient magma-rich rifts, as evidenced by top-rift unconformities. Magma-rich margins show anomalously fast and large post-tectonic subsidence, evidenced by thick, short-lived little-faulted sag–salt sections. Syndepositional thermal subsidence cannot be responsible alone, and lack of faulting argues against tectonic subsidence. We argue that dissipation of dynamic topography (dynamic subsidence) is the additional component with thermal subsidence. We depict the formation of the magma-rich central South Atlantic and Gulf of Mexico salt-bearing margins relative to former plumes, showing that sag–salt deposition occurs as the margins migrate off plume flanks while supra-plume rifting continues. However, the pre-sag–salt basement must first be extended or eroded during dynamic elevation to fall below its pre-uplift elevation. 'Dynamo-thermal subsidence' creates 'dynamo-thermal accommodation', the sum and combined result of dynamic plus thermal subsidence, respectively. It is fast enough to negate the need for deep, sub-sea-level, subaerial depressions for accumulation of thick sag–salt sections. Also, differences in dynamic elevation during salt deposition explain differences in autochthonous salt thickness. Supplementary material: Supplementary figures, seismic data, structural restorations, a compilation of igneous activity and an extended figure caption are available at https://doi.org/10.6084/m9.figshare.c.5908896 [ABSTRACT FROM AUTHOR]

Connect fifth bracelet strand onto the loop end of the pin you have just made, first bracelet strand to the loop at the other end of the eyepin. Connect fifth bracelet strand onto loop pin you have just made, and the first bracelet strand to the loop at the other end of the eyepin. Projects TOOLS Round nose pliers Chain nose pliers Wire cutters MATERIALS 2 x 41mm Ancient Gold eyepins 86 x 25mm Ancient Gold eyepins 1 x 4mm Ancient Gold jumpring 1 x Ancient Gold Toggle clasp BEADS Bracelet Strands: Swarovski Crystal 5301 bi-cones 4 x 4mm Light Siam AB 3 x 6mm Light Siam 4 x 4mm Padparadscha 3 x 6mm Padparadscha 6 x 4mmTopaz AB 2 x 6mm Topaz 4 x 4mm Smoked Topaz 3 x 6mm Smoked Topaz 5 x 4mm Olivine 1 x 6mm Olivine 5 x 4mm Light Olivine 3 x 6mm Light Olivine 4 x 4mm Blue Zircon 3 x 6mm Blue Zircon 6 x 4mm Fuchsia 1 x 6mm Fuchsia 4 x 4mm Purple Velvet 3 x 6mm Purple Velvet 4 x Montana 4 x 4mm Amethyst 3 x 6mm Amethyst For End Bars: 1 x 4mm Topaz AB 1 x 4mm Blue Zircon 1 x 4mm Olivine 1 x 4mm Padparadscha 1 x 6mm Padparadscha 1 x 6mm Light Olivine 1 x 6mm Light Siam 1 x 6mm Purple Velvet For Clasp Attachment: 2 x 4mm Blue Zircon 2 x 4mm Amethyst 2 x 4mm Montana 2 x 4mm Fuchsia 2 x 4mm Purple Velvet 2 x 4mm Smoke Topaz 1 x 4mm Light Siam AB LENGTH: 20cm STEP ONE Using all beads from the "Bracelet Strands" materials list, place each bi-cone onto an eyepin. [Extracted from the article]

The perfect piece for layering, the Olivine Top will have you knitting up lace in no time. At beg of RS rows, BO 4 sts 2 times, then BO 2 sts 2 times, then BO 1 st 3 times - 4 (6, 8, 9, 9, 10, 10, 11) sts rem. At beg of WS rows, BO 4 sts 2 times, then BO 2 sts 2 times, then BO 1 st 3 times - 4 (6, 8, 9, 9, 10, 10, 11) sts rem. [Extracted from the article]

The article focuses on the tragic accidental death of Philip Brady in 1894 due to a leg artery rupture, examining the circumstances surrounding his demise, the limitations of medical care during that time, and the impact of this incident on the community. Topics include the details of Brady's accident, the medical constraints of the era, and the implications of such an incident on the local community, highlighting the lack of advanced medical procedures available during that period.

A recent study conducted at Tafila Technical University in Jordan investigated the removal of paracetamol, a widely used drug, from water using Jordanian olivine. The olivine was characterized using various analytical techniques. The study found that the percentage of paracetamol removed increased with increased time in the presence of ultrasonic waves. The research concluded that Jordanian olivine can be efficiently used for the treatment of paracetamol-containing water and wastewater. This study has been peer-reviewed and published in the journal Desalination and Water Treatment. [Extracted from the article]

STEP SEVEN Take 1 x pearl head pin, thread 1 x freshwater pearl, 1 x Chrysolite bi-cone. STEP ELEVEN Take 1 x pearl head pin, thread 1 x Czech Rosebud bead. Projects MATERIALS 1 x Vintaj "Dream" ring 1 x Vintaj "Love" ring 1 x Vintaj "Hope" ring 1 x Vintaj "Believe" ring 15 x 8mm Vintaj jump rings 5 x 4mm Vintaj jump rings 2 x 5mm Vintaj jump rings 2 x Vintaj pearl head pins 1 x 25mm Vintaj head pins 1 x Vintaj eye pin 1 x Vintaj bird charm 1 x Vintaj pendant bale 1 x Filigree Butterfly charm 1 x Vintaj Nouveau Swirls clasp set 30cm Vintaj Rollo chain BEADS 2 x 4mm Swarovski bi-cones - 1 x Chrysolite, 1 x Cobalt 1 x freshwater pearl 1 x 10mm Swarovski Heart - Rose 1 x Czech Rosebud bead TOOLS Chain nose pliers Round nose pliers Wire cutters LENGTH: 50cm Rating STEP ONE Open 1 x 8mm jump ring; thread on 2 x jump rings. [Extracted from the article]

Interdiffusion of Fe-Mg in olivine was modelled in 29 crystals in total, from six olivine-normative basalt thin sections and from three quartz-normative basalt thin sections. Based on differing wholerock major element chemistry, these groups are the quartz-normative basalt suite and the olivine-normative basalt suite.". [Extracted from the article]

The article discusses the history of diamond exploration in the Northwest Territories and Canada. Exploration began in 1981 in the Mackenzie Mountains. By 1990, diamond-bearing kimberlite were traced to the Lac de Gras area and subsequent drilling in 1991 triggered the biggest claim staking rush in Canada's history covering more than 28 million hectares in the Northwest Territories and Nunavut. Production of the first diamond mine in the area started in 1998.

The mid-ocean ridge (MOR)-type gabbroic sequences from the Internal Ligurian ophiolites include olivine-rich troctolite lenses up to tens of metres thick. For one of these lenses, a portion of metre-scale thickness characterized by skeletal to dendritic olivines (harrisites) was observed near the contact with host gabbros. Spinels from the olivine-rich troctolites locally include Ti-pargasite to kaersutite frequently associated with phlogopite to Na-phlogopite. Spinel-hosted amphibole displays rare earth element (REE) patterns characterized by a negative Eu anomaly, thereby recording a magmatic process associated with plagioclase segregation. The amphiboles show variable depletion of light REE (LREE) relative to middle REE (MREE), and heavy REE (HREE) that are weakly enriched to depleted with respect to MREE. Crystallization of the inclusion-bearing spinels is attributed to cooling of hybrid melts that originated by interaction between primitive melts and gabbro-related melts relatively rich in SiO2 and incompatible elements. Clinopyroxene and amphibole from the harrisites show extensive variability for trace element compositions, albeit characterized by subparallel incompatible element patterns. This chemical variability was most probably acquired in response to rapid crystal growth related to undercooling of the harrisite parental melt.We propose that the melt undercooling was related to interaction of a primitive melt batch with a gabbroic crystal mush. [ABSTRACT FROM AUTHOR]

Projects MATERIALS 1 x hammered round gold plated 1 x olivine green fish focal component 22 gauge non tarnish wire gold ZM Gold plated fine Figaro chain 2 x 4mm jump rings gold plated 1 x key theme toggle clasp gold plated BEADS 4 x Czech glass olivine lustre ovals 6 x 8mm Swarovski bi-cones peridot 2 x 5x10mm teardrops olivine green AB 20 x 4mm daisy spacers gold TOOLS Chain nose pliers Round nose pliers Wire cutters LENGTH: 45-50cm Rating STEP ONE Cut chain into 2 x 3cm, 2 x 5cm, 4 x 6cm lengths. STEP FIVE Wire wrap the olivine nuggets in between the chain segments referring to the photograph as a guide. STEP THREE Onto the wires thread 1 x 4mm spacer, 1 x olivine nugget, 1 x 4mm spacer. [Extracted from the article]

Polycrystalline aggregates lacking four independent systems for the glide of dislocations can deform in a purely viscoplastic regime only if additional deformation mechanisms (such as grain boundary sliding and diffusion) are activated. We introduce an implementation of the self-consistent scheme in which this additional physical mechanism, considered as a stress relaxation mechanism, is represented by a nonlinear isotropic viscoplastic potential. Several nonlinear extensions of the self-consistent scheme, including the second-order method of Ponte-Castañeda, are used to provide an estimate of the effective viscoplastic behavior of such polycrystals. The implementation of the method includes an approximation of the isotropic potential to ensure convergence of the attractive fixed-point numerical algorithm. The method is then applied to olivine polycrystals, the main constituent of the Earth's upper mantle. Due to the extreme local anisotropy of the local constitutive behavior and the subsequent intraphase stress and strain-rate field heterogeneities, the second-order method is the only extension providing qualitative and quantitative accurate results. The effective viscosity is strongly dependent on the strength of the relaxation mechanism. For olivine, a linear viscous relaxation (e.g. diffusion) could be relevant; in that case, the polycrystal stress sensitivity is reduced compared to that of dislocation glide, and the most active slip system is not necessarily the one with the smallest reference stress due to stress concentrations. This study reveals the significant importance of the strength and stress sensitivity of the additional relaxation mechanism for the rheology and lattice preferred orientation in such highly anisotropic polycrystalline aggregates. [ABSTRACT FROM AUTHOR]

The article discusses alternatives to traditional olivine sand available to nonferrous olivine sand casters in North America. The cost disadvantage of importing Norwegian olivine sand is cited. The three major cost-effective options to traditional olivine sand are silica sand, Green Diamond aggregate or Biasill aggregate. Some reasons why metalcasters use olivine sand are discussed including its fine surface finish characteristics and thermal expansion properties.

The article presents the conclusions of several presentations selected from the 116th Metalcasting Congress that took place in Columbus, Ohio on April 17-20, 2012. "Hot Tearing in Cast Al Alloys: Controls" by Shimin Li and colleagues examined actual castings and simulated results. "Replacement of Olivine with Silica Sand in Non-Ferrous Foundries" by Victor LaFay and colleagues focuses on operational difference between silica sand and olivine sand in metalcasting facilities.

The article discusses the petrographic descriptions of meteorites. It says that the CO3 chondrite found in Dominion Range are black fractured fusion crust with oxidation and evaporites is visible to varying degrees in paired carbonaceous chondrites. It mentions that the Pallasite found in Miller Range has a common weathering and exterior morphology and exhibits a rusty exterior with removal of olivine. It adds that howardite's exterior surface consists of 80% shiny black crust.

The article looks at the potential problem posed by a shortage of sand for metalcasters in the U.S. Dave Jablonski, who handles metalcasting sales for sand miner and distributor Badger Mining Corp., explains the need for greater amounts of silica sand, which is a primary ingredient in hydraulic fracturing. The supply condition for other sands such as olivine and zircon is also analyzed. The options offered by industry experts to metalcasters faced with such a shortage include using different sand or using less sand.

The article focuses on the black Almahata Sitta meteorites recovered from the Nubian Desert of northern Sudan. It says that the meteorites were part of the 2008 TC asteroid considered to be one of the three fastest-spinning asteroids known. The meteorites belong to class known as ureilites but are unique for their holes lined with crystals of the magnesium-rich silicates olivine and pyroxene. It is noted that the asteroid was the first one among those seen to have actually landed on earth.

Skilled gem cutter Andreas Becker was able to create exquisite peridot gems out of olivine crystals that came from the Esquel meteorite. The gems were a success when exhibited at the 1991 Intergem show held in Idar-Oberstein, Germany, the European gem cutting center.

The article discusses the results of studies to determine the mechanisms that cause veining defects in iron and steel castings. Topics discussed include how veining defect in cores and molds comes from a tensile stress exerted by a combination of contracting sand, the development of dilatometer to provide the temperature range and degree of accuracy required and accepted methods of reducing veining defects in casting such as the use of low expansion aggregates like chromite, zircon and olivine.

An interview with Todd Hoefen, a geophysicist at the U.S. Geological Survey in Denver, Colorado, is presented. When asked which research connected with environmental disasters in U.S. history has affected him the most, Hoefen said that the World Trade Center disaster affected him the most, being an upstate New Yorker. When asked about his most important scientific discovery, Hoefen named his discovery of olivine in Nili Fossae region of Mars in 2000 while analyzing Thermal Emission Spectrometer data from the Mars Global Surveyor mission.

The article reports on the findings of the study of comet dust samples brought back to the Earth by the U.S. National Aeronautics and Space Administration (NASA)'s comet catcher, Stardust. The findings, announced by NASA, comes from studying about two dozen of the million or so dust grains captured from Comet Wild 2 and parachuted back to Earth in a capsule just two months ago. The dust grains contain minerals such as olivine, pyroxene and spinel, which form at red-hot or white-hot temperatures. Comet Wild 2 is thought to have formed and spent most of its life in the Kuiper belt, a ring of icy objects beyond Neptune. So some of its dust may have originated close to the sun, within the orbit of Mercury, or even near another star before being transported to the Kuiper belt.

The article focuses on research reported during the geochemistry conference Goldschmidt in Boston, Massachusetts on August 14, 2018 on a new method to accelerate formation of magnesite to capture the greenhouse gas carbon dioxide at room temperature. It states that olivine in northern British Columbia becomes enriched with carbonate and magnesium ions and then forms magnesite. It comments that polystyrene microspheres coated with carboxyl act as catalysts accelerating the reaction.

The article reports that researchers from the National Institute for Environmental Studies in Japan have studied olivine-rich sites on the surface of the moon. During its lunar mission, the Japanese spacecraft KAGUYA identified sites in the moon's surface that are rich in olivine, a mineral which is thought to come from the deep interior of the moon. Based on distribution maps created by the researchers, most of olivine-rich rocks were located near the crater. This suggests the olivine originated from the mantle d only came to the surface by impacts.

The article focuses on the results of a study which found that argon may not act as once thought on its way from the core-mantle boundary to the atmosphere. Researchers from Rensselaer Polytechnic Institute in New York heated olivine and orthopyroxene, the two main minerals composing the mantle of the Earth, in an argon atmosphere and discovered that argon likes to sit in such minerals and that it would be difficult to get them out into the atmosphere during melting. It says that the results of the study have prompted mixed reactions among geoscientists.

Reports the detection of olivine crystals on the surface of the planet Mars using data from the Thermal Emission Spectrometer aboard United States National Aeronautics and Space Administration's Mars Global Surveyor orbiter. How olivine was detected by researcher Roger N. Clark and Todd M. Hoefen; Implications of the olivine detection; Other researchers proposing a dry Mars.

The article discusses the discovery of olivine on Vesta asteroid. Topics covered include the spacecraft that made the discovery, implications for space science and impact on theories about the evolution of rocky planets. Also mentioned is the use of data collected by Dawn spacecraft's Visible and Infrared Mapping Spectrometer in 2012.

This article reports on research conducted by astronomer Ben de Vries that was published in the October 4, 2012 issue of "Nature" concerning the discovery of the olivine, a mineral found heavily in the comets of the Earth's solar system, in a cold debris disk surrounding the star Beta Pictoris.

An introduction to the journal is presented in which the editors various articles published within the issue including "Replacing Olivine Sand," "More Than a Makeover: Reinventing A&B Foundry" and "46th Census of World Casting Production."

The article cites a report that appeared in the June 1, 2011 issue of "The Astrophysical Journal Letters" regarding research by Charles Poteet and colleagues of the University of Toledo in Ohio, who discovered olivine crystals falling into the protostar HOPS-68.

The article discusses the discovery of the distant star HD 131488 by astronomer Carl Melis, announced at a January 2010 meeting of the American Astronomical Society. The uncertain characteristics of dust orbiting the star are noted. Unlike dust found orbiting other stars, dust of HD 131488 does not contain olivine, pyroxene, or silica minerals.

The article discusses the characteristics and feature of asbestos. According to the author, asbestos is a generic name for six needle-shaped minerals that possess high tensile strengths, flexibility, and resistance to chemical and thermal degradation. These minerals are actinolite, amosite, anthophyllite, chrysolite, crocilodite and tremolite. Asbestos is used for strengthening concrete pipe, plastic components, and gypsum plasters.

This section offers product innovation-related news briefs. The Benton Foundry in Benton, Pennsylvania has installed a new Disa Match 28/32 molding machine after determining that its molding process was labor intensive. Beaver Valley Alloy (BVA) in Monaca, Pennsylvania has implemented the use of Humtown Products when pouring Hadfield manganese steel for olivine and cores.

The article focuses on research being done by Jürg Matter and Peter Kelemen of Columbia University's Lamont-Doherty Earth Observatory in New York, on the possibility of trapping carbon dioxide in peridotite rock. They believe that peridotite is rich in olivine mineral which reacts with carbon dioxide and water to form solid carbonate rock. Matter and Kelemen are hoping to find funding for their research and continue their experiment in a peridotite conglomerate in Oman.

The article discusses research on the use of mineral olivine in predicting volcanoes' future behavior. Daniel Morgan, a volcanologist at the University of Leeds in England, and his colleagues examined olivine crystals in lava from the 1925 eruption of the Nea Kameni Volcano in Santorini, Greece. Researchers believe that the use of olivine crystals in their study enables them to study volcanoes that last erupted centuries ago and gives them insight into how much warning they will have when the seismometers first go off.

This article reports on the plan of SilMag to reopen a magnesium plant in Norway in 2008. The company aims to produce 35,000 tonnes of magnesium per year from the plant. Managing director Per Engseth and director of sales and marketing Svenn-Ivar Stromhaug will run the company. The plant will use olivine as a raw material.

The article discusses a report by astronomers studying materials collected by the National Aeronautics and Space Administration's Stardust mission published in the January 25, 2008 issue of "Science." Collected material came from the tail of Comet 81P/Wild 2 and include olivine, a substance made of iron and magnesium formed in high pressure and temperature. The traditional hypothesis that comet-material was never heated by solar radiation is questioned.

The article reports on scientists at the Australian Antarctic Division in Kingston, University of Western Ontario in London, Aerospace Corp. and Sandia and Los Alamos National Laboratories in New Mexico's use of light detection and ranging to suggest that the dominant contribution to the mass of the residual atmospheric aerosol was micrometer-size particles. According to lidar depolarization backscatter data, the anomalous cloud detected in the upper stratosphere, was dominated by micrometer-size nonspherical particles of olivine and pyroxene.

This article reports that a piece of breccia from the Moon found in Africa has the youngest date known for a lunar rock: 2.865 billion years. This is several hundred million years younger than any mare basalt and about a billion years younger than any lunar rock of its kind. The baseball-size meteorite, Northwest Africa 773 [NWA 773], contains breccia, rock fragments welded by impact. The largest chunk, though, is olivine gabbro, analyzed by a team under Lars Borg. "We found that NWA 773 has the youngest crystallization age for any lunar material," says Borg. The Moon may have younger rocks, he notes, but they have not yet been found.

Reports on the presence of olivine, a mineral that undergoes rapid transformation into other minerals when exposed to liquid water, in Mars. Findings of the Mars Global Surveyor spacecraft of the National Aeronautics and Space Administration; Research conducted by Todd M. Hoefen of the U.S. Geological Survey and Philip R. Christensen of the Arizona State University in Tempe on the field; Region in Mars where olivine is abundant.

Presents a study which examined basanites related to the Eocene period in Northeastern Oman. Description of the regional geology of eastern Oman; Analysis of petrographic populations of olivine found in rocks collected from the area; Overview of the tertiary sedimentary history of the Batain area.