Analcime phenocrysts in igneous rocks: Primary or secondary
... are due to alteration of glass rather than alteration of analcime. Although the Crowsnest locality is noteworthy for its large fresh analcime crystals, such pristine analcime is actually rare within the formation. Most of the analcime is altered in some fashion. It might be stressedhere that the alt ...
... are due to alteration of glass rather than alteration of analcime. Although the Crowsnest locality is noteworthy for its large fresh analcime crystals, such pristine analcime is actually rare within the formation. Most of the analcime is altered in some fashion. It might be stressedhere that the alt ...
Workshop Report - Consortium for Ocean Leadership
... processes of mantle melting, melt aggregation and transport have undergone large advances with the integration of mantle geochemistry and rock physics. There was considerable discussion of the origin and consequences of focused viscous deformation along mantle shear zones, with application to meltin ...
... processes of mantle melting, melt aggregation and transport have undergone large advances with the integration of mantle geochemistry and rock physics. There was considerable discussion of the origin and consequences of focused viscous deformation along mantle shear zones, with application to meltin ...
Magmatic Apatite: A Powerful, Yet Deceptive
... elongate). Equant apatite is generally defi ned by wellformed crystal faces (FIG. 1), and is often easily recognized by its hexagonal shape. This habit is interpreted to have grown under near-equilibrium conditions. Less commonly, equant apatite occurs with no well-formed crystal faces as an interst ...
... elongate). Equant apatite is generally defi ned by wellformed crystal faces (FIG. 1), and is often easily recognized by its hexagonal shape. This habit is interpreted to have grown under near-equilibrium conditions. Less commonly, equant apatite occurs with no well-formed crystal faces as an interst ...
- ISP 205, sec 1 - Visions of the
... able to gain gas through the process of bombardment, while Earth has not gained gas in this way. B Earth has lost much more gas to thermal escape than has Venus. C Earth has lost much more atmospheric gas than Venus, primarily to condensation of water vapor into liquid water and to chemical reaction ...
... able to gain gas through the process of bombardment, while Earth has not gained gas in this way. B Earth has lost much more gas to thermal escape than has Venus. C Earth has lost much more atmospheric gas than Venus, primarily to condensation of water vapor into liquid water and to chemical reaction ...
Transfer of melts in the sub-arc mantle: Insights from high
... (Prinzhofer et al., 1980; Paris, 1981). The Massif du Sud stands as a wonderful natural case study of large scale features for melt transport in the upper part of the mantle. The New Caledonia ophiolite is also well known to be extremely depleted geochemically (Prinzhofer & Allègre, 1985; Marchesi e ...
... (Prinzhofer et al., 1980; Paris, 1981). The Massif du Sud stands as a wonderful natural case study of large scale features for melt transport in the upper part of the mantle. The New Caledonia ophiolite is also well known to be extremely depleted geochemically (Prinzhofer & Allègre, 1985; Marchesi e ...
Euler: Genius Blind Astronomer Mathematician
... telescopes.4 Euler’s accomplishments include determining with great accuracy the orbits of comets and other celestial bodies, and calculating the parallax of the Sun. He also made direct observations of the Moon and Sun. Euler’s passion for the stars never diminished, even when he lost vision in bot ...
... telescopes.4 Euler’s accomplishments include determining with great accuracy the orbits of comets and other celestial bodies, and calculating the parallax of the Sun. He also made direct observations of the Moon and Sun. Euler’s passion for the stars never diminished, even when he lost vision in bot ...
CHEOPS Definition Study Report
... The CHaracterising ExOPlanet Satellite (CHEOPS) mission was proposed in response to the “2012 Call for a Small mission opportunity in ESA's Science Programme for a launch in 2017”, issued on 9 March 2012. The proposal was led by Prof. Willy Benz from the University of Bern. Following the review and ...
... The CHaracterising ExOPlanet Satellite (CHEOPS) mission was proposed in response to the “2012 Call for a Small mission opportunity in ESA's Science Programme for a launch in 2017”, issued on 9 March 2012. The proposal was led by Prof. Willy Benz from the University of Bern. Following the review and ...
Lower Continental Crust. - UCSB Earth Science
... (1990) assembled a database of rock compositions from Archean and post-Archean terrains recrystallized at >0.6 GPa. Huang et al. (2013) updated this database and added a compilation of amphibolite-facies samples. We augmented their granulite data with additional analyses from the literature, and her ...
... (1990) assembled a database of rock compositions from Archean and post-Archean terrains recrystallized at >0.6 GPa. Huang et al. (2013) updated this database and added a compilation of amphibolite-facies samples. We augmented their granulite data with additional analyses from the literature, and her ...
Professor Comet: April, 2017
... Jovian (Jupiter) Family of Comets These are nearby comets that reside between the boundary of the inner and outer planetary solar system with orbital periods between 3 – 20 years. There current orbits are influenced by the strong gravitational field of Jupiter which can adjust all or most of the orb ...
... Jovian (Jupiter) Family of Comets These are nearby comets that reside between the boundary of the inner and outer planetary solar system with orbital periods between 3 – 20 years. There current orbits are influenced by the strong gravitational field of Jupiter which can adjust all or most of the orb ...
Jewel of the Solar System INTRODUCTION
... Kids love space, and their favorite planet is often the magnificent ringed “Jewel of our Solar System” – Saturn! Saturn is the sixth planet from our Sun and the second largest planet in our Solar System (after Jupiter). Pressures and temperatures inside Saturn are so extreme that they cannot be dupl ...
... Kids love space, and their favorite planet is often the magnificent ringed “Jewel of our Solar System” – Saturn! Saturn is the sixth planet from our Sun and the second largest planet in our Solar System (after Jupiter). Pressures and temperatures inside Saturn are so extreme that they cannot be dupl ...
nature and composition of the continental crust
... a data redundancy that permits use of a wide array of signal processing methods (e.g., stacking) for amplitude enhancement and correlation of reflected phases over large distances. Additionally, the higher-frequency content of energy sources in near-vertical surveys (e.g., air guns and vibrators) pr ...
... a data redundancy that permits use of a wide array of signal processing methods (e.g., stacking) for amplitude enhancement and correlation of reflected phases over large distances. Additionally, the higher-frequency content of energy sources in near-vertical surveys (e.g., air guns and vibrators) pr ...
Evolution of Metamorphic Belts - CiteSeerX
... It is clear that the prevailing rock pressure in the andalusite-sillimanite type is lower than that in the kyanite-sillimanite type, which latter in turn is lower than that in the jadeite-glaucophane type. If it be assumed that the pressures shown in this figure were produced lithostatically by the ...
... It is clear that the prevailing rock pressure in the andalusite-sillimanite type is lower than that in the kyanite-sillimanite type, which latter in turn is lower than that in the jadeite-glaucophane type. If it be assumed that the pressures shown in this figure were produced lithostatically by the ...
Satellite names worth remembering
... Neptune also has the usual horde of smaller satellites: Nereid, Galatea, Naiad, Proteus, and others. Half of them were discovered by the Voyager 2 spacecraft when it passed that planet in ...
... Neptune also has the usual horde of smaller satellites: Nereid, Galatea, Naiad, Proteus, and others. Half of them were discovered by the Voyager 2 spacecraft when it passed that planet in ...
o-Emitting mineral inclusions in apatite, their effect on (U–Th
... U–Th rich mineral inclusions in apatite are often held responsible for erroneously old (U–Th)/He ages, because they produce ‘‘parentless’’ He. Three aspects associated with this problem are discussed here. First, simple dimensional considerations indicate that for small mineral inclusions, the paren ...
... U–Th rich mineral inclusions in apatite are often held responsible for erroneously old (U–Th)/He ages, because they produce ‘‘parentless’’ He. Three aspects associated with this problem are discussed here. First, simple dimensional considerations indicate that for small mineral inclusions, the paren ...
2.03 Sampling Mantle Heterogeneity through Oceanic Basalts
... Vollmer, 1976). Hofmann and Hart (1978) reviewed this subject in light of the available diffusion data in solid and molten silicates. They concluded that mineral-scale isotopic and chemical disequilibrium is exceedingly unlikely, if melting timescales are on the order of thousands of years or more. ...
... Vollmer, 1976). Hofmann and Hart (1978) reviewed this subject in light of the available diffusion data in solid and molten silicates. They concluded that mineral-scale isotopic and chemical disequilibrium is exceedingly unlikely, if melting timescales are on the order of thousands of years or more. ...
u series disequilibria: insights into mantle melting and
... and melt-matrix interaction); (2) the elapse of time since the fractionation event during which radioactive decay will occur (e.g., melt transport time from mantle source regions to the crust, residence time in crustal magma reservoirs, and time since lava eruption); and (3) surface weathering or hy ...
... and melt-matrix interaction); (2) the elapse of time since the fractionation event during which radioactive decay will occur (e.g., melt transport time from mantle source regions to the crust, residence time in crustal magma reservoirs, and time since lava eruption); and (3) surface weathering or hy ...
Oort Cloud Formation and Dynamics
... of the planetesimals onto planet-crossing orbits in 10 m.y. or less (Gladman and Duncan, 1990; Holman and Wisdom, 1993; Levison and Duncan, 1993; Grazier et al., 1999a,b). The major exception to this rule is in the Kuiper belt, where some orbits remain stable for billions of years (Holman and Wisdom ...
... of the planetesimals onto planet-crossing orbits in 10 m.y. or less (Gladman and Duncan, 1990; Holman and Wisdom, 1993; Levison and Duncan, 1993; Grazier et al., 1999a,b). The major exception to this rule is in the Kuiper belt, where some orbits remain stable for billions of years (Holman and Wisdom ...
Science Bowl Questions and Answers
... ASTR-91; Short Answer: I am a type of star with a relatively low effective temperature (3,000 to 4,000 Kelvins), and have a large radius-about 100 times that of the Sun. What am I? ANSWER: RED GIANT ASTR-91; Short Answer: A 5th magnitude star is how many times brighter than an 8th magnitude star? AN ...
... ASTR-91; Short Answer: I am a type of star with a relatively low effective temperature (3,000 to 4,000 Kelvins), and have a large radius-about 100 times that of the Sun. What am I? ANSWER: RED GIANT ASTR-91; Short Answer: A 5th magnitude star is how many times brighter than an 8th magnitude star? AN ...
On the Migratory Behavior of Planetary Systems The Harvard
... on planetary systems. However, there is growing evidence that many planetary systems underwent a period of upheaval, during which giant planets “migrated” from where they formed. This thesis addresses a question key to understanding how planetary systems evolve: is planetary migration typically a sm ...
... on planetary systems. However, there is growing evidence that many planetary systems underwent a period of upheaval, during which giant planets “migrated” from where they formed. This thesis addresses a question key to understanding how planetary systems evolve: is planetary migration typically a sm ...
Paleozoic–Mesozoic Porphyry Cu(Mo) and Mo(Cu) Deposits within
... other hand, some researchers consider the subduction-metasomatized mantle lithosphere as a possible source of Mo [3]. Copper is generally considered to be derived from the mantle [1,4]. Nevertheless, some researchers suggest a hybridized lower continental crustal source of Cu [5]. Porphyry Cu–Mo dep ...
... other hand, some researchers consider the subduction-metasomatized mantle lithosphere as a possible source of Mo [3]. Copper is generally considered to be derived from the mantle [1,4]. Nevertheless, some researchers suggest a hybridized lower continental crustal source of Cu [5]. Porphyry Cu–Mo dep ...
Resonant Origins for Pluto`s High Inclination
... et al.’s spectral analysis of a 200 Myr numerical simulation of the Solar System [2]. As this resonance involves the nodes of both planets, it has the ability to affect their inclinations. A careful study is needed, then, to explore this and related resonances before, during, and after the migration ...
... et al.’s spectral analysis of a 200 Myr numerical simulation of the Solar System [2]. As this resonance involves the nodes of both planets, it has the ability to affect their inclinations. A careful study is needed, then, to explore this and related resonances before, during, and after the migration ...
Professor Comet: March, 2017
... Jovian (Jupiter) Family of Comets These are nearby comets that reside between the boundary of the inner and outer planetary solar system with orbital periods between 3 – 20 years. There current orbits are influenced by the strong gravitational field of Jupiter which can adjust all or most of the orb ...
... Jovian (Jupiter) Family of Comets These are nearby comets that reside between the boundary of the inner and outer planetary solar system with orbital periods between 3 – 20 years. There current orbits are influenced by the strong gravitational field of Jupiter which can adjust all or most of the orb ...
Origin of ocean island basalts: A new perspective from petrology
... the conclusion of the test; 20% melting is higher than a mean value of 15% melting beneath present-day ocean ridges [Niu, 1997] but is reasonable given the hotter mantle in the past. Again, different choices of extent of melting do not affect the conclusion of the test. Figure 1 shows that the isoto ...
... the conclusion of the test; 20% melting is higher than a mean value of 15% melting beneath present-day ocean ridges [Niu, 1997] but is reasonable given the hotter mantle in the past. Again, different choices of extent of melting do not affect the conclusion of the test. Figure 1 shows that the isoto ...
Collisional processes in extrasolar planetesimal discs
... planetesimal population. Also, we note that such intrinsic clumpiness in an exozodiacal cloudlike disc could present a confusion limit when trying to detect terrestrial planets. (v) The observed clump could have originated in a collision between two runaway planetesimals, both larger than 1400 km in ...
... planetesimal population. Also, we note that such intrinsic clumpiness in an exozodiacal cloudlike disc could present a confusion limit when trying to detect terrestrial planets. (v) The observed clump could have originated in a collision between two runaway planetesimals, both larger than 1400 km in ...
Late Heavy Bombardment
The Late Heavy Bombardment (abbreviated LHB and also known as the lunar cataclysm) is a hypothetical event thought to have occurred approximately 4.1 to 3.8 billion years (Ga) ago, corresponding to the Neohadean and Eoarchean eras on Earth. During this interval, a disproportionately large number of asteroids apparently collided with the early terrestrial planets in the inner Solar System, including Mercury, Venus, Earth, and Mars. The LHB happened after the Earth and other rocky planets had formed and accreted most of their mass, but still quite early in Earth's history.Evidence for the LHB derives from lunar samples brought back by the Apollo astronauts. Isotopic dating of Moon rocks implies that most impact melts occurred in a rather narrow interval of time. Several hypotheses are now offered to explain the apparent spike in the flux of impactors (i.e. asteroids and comets) in the inner Solar System, but no consensus yet exists. The Nice model is popular among planetary scientists; it postulates that the gas giant planets underwent orbital migration and scattered objects in the asteroid and/or Kuiper belts into eccentric orbits, and thereby into the path of the terrestrial planets. Other researchers argue that the lunar sample data do not require a cataclysmic cratering event near 3.9 Ga, and that the apparent clustering of impact melt ages near this time is an artifact of sampling materials retrieved from a single large impact basin. They also note that the rate of impact cratering could be significantly different between the outer and inner zones of the Solar System.