Composition and origin of garnet from the Antarctic Peninsula Volcanic Group of Trinity Peninsula

first_imgGarnet is widely found as a minor constituent in rocks of the Antarctic Peninsula Volcanic Group (APVG) of Trinity Peninsula. It occurs as conspicuous megacrysts, or in xenoliths within volcanic rocks of andesitic-rhyolitic composition and as detrital grains in the associated terrestrial sediments. It is also found as an accessory mineral in many plutonic rocks from the E coast of the Antarctic Peninsula. Evidence is presented to show that the garnet can be divided petrographically and chemically into two main groups: Type A: almandine-rich primary igneous garnet, and Type B: less almandine- and more pyrope-rich garnet as xenocrysts or included in xenoliths within the volcanic rocks. Comparison with published experimental data on garnet occurrence in acidic igneous rocks suggests that high almandine-low spessartine garnet in volcanic rocks is a remnant phase of high pressure crystallization from magma at pressures of >7 kbar. Garnet with a higher pyrope content is regarded as xenocrystal in origin, having been derived from garnet-bearing country rocks at depth, either as accidental inclusions or through direct partial melting (restite) of the lower crust, and implies that a considerable thickness (>25 km) of crustal material was in existence before the generation of the Mesozoic magmatic arc. The origin of these calc-alkaline magmas may therefore be due, at least in part, to partial melting of pre-existing sialic crustal material.last_img read more

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Wellington Police Notes: Monday, May 16, 2016

first_imgWellington Police notes: Monday, May 16, 2016:•12:00 p.m. Officers took a report of suspicious Aativity in the 1200 block Highland Court, Wellington.•3:41 p.m. Officers investigated domestic battery and criminal carry of weapons in the 800 block N. Woodlawn, Wellington by known suspect.•3:51 p.m. Justin W. Corter, 33, Wellington was arrested, charged and confined with domestic battery and criminal carry of weapons.•5:35 p.m. Non-Injury accident in the area of U.S. 81 and U.S. 160, Wellington involving vehicles operated by Natasha M. Gurley, 20, Wellington and William E. Brown, 28, Caldwell.•5:35 p.m. Officers investigated operating a motor vehicle without a valid license in the 300 block W. 8th, Wellington.•5:45 p.m. Natasha M. Gurley, 20, Wellington was issued a notice to appear for inattentive driving.•5:45 p.m. William E. Brown, 28, Caldwell, was issued a notice to appear for driver’s license violation.last_img read more

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Friday April 10th Local Sports

first_imgWAVERLY —- Wartburg and Iowa State will square-off for the first time in a quarter century when the 2020-21 college wrestling season gets underway. The dual meet between the 14-time Division III national champion Knights and eight-time Division I national champion Cyclones is scheduled for November 6th at Hilton Coliseum in Ames. The season-opener will be only the third meeting in history between the teams and the first since Iowa State’s 23-16 win at Wartburg in 1996, the year the Knights won their first national title in program history. Wartburg finished the 2019-20 campaign with a 16-1 overall record and Iowa State finished second at the Big 12 Championships. The Knights are 12-11-1 all-time against Division I competition. The last time Wartburg faced a D-I opponent was in 2011, when the Knights dropped a 17-16 tiebreaker at Wisconsin. AMES — Iowa State women’s basketball coach Bill Fennelly says his team is focusing on what it accomplished and not what was lost with the cancelation of the post-season. The Cyclones were 18-11 and finished the regular season on a three game winning streak.Iowa State’s final game was a stunning upset of second ranked and defending national champion Baylor.Iowa State ended up 10-8 in Big 12 regular season play. IOWA CITY —- Iowa athletic director Gary Barta says they will be able to cover financial losses with reserves between now and the end of the fiscal year on June 30th. Barta says the department expects to lose several million dollars due to the loss of the Big Ten and NCAA basketball tournaments.Barta says they are looking at options for the next fiscal yearBarta says they will be looking at possible pay cuts in the future.Barta says they will be looking at several ways to save money. MASON CITY — NIACC coach Todd Ciochetto and sophomore Autam Mendez were recognized on Thursday by the National Junior College Athletic Association as the Division II women’s basketball coach and player of the year. Ciochetto guided the Lady Trojans to a 32-1 overall record, including a perfect 16-0 mark in Iowa Community College Athletic Conference play. NIACC won the Region XI title but did not play in the national tournament after it was cancelled due to the COVID-19 pandemic. Ciochetto wrapped up his sixth season as NIACC’s head coach with an overall record of 153-46. Mendez became NIACC’s first-ever national player of the year on Thursday. The 5-10 guard from St.Paul averaged 16.9 points per game in her sophomore year, recording 12 double-doubles. Mendez finished third on the school’s career scoring list with 1045 points, as well as third on the school’s career three-point and rebounding lists. Mendez has committed to continue her basketball career at San Jose State. THIS WEEKEND ON AM-1300 KGLO:Friday night at 7:00 — July 6 2007 — Twins vs. White Sox — Justin Morneau hits three homersSaturday afternoon at 12:00 — Iowa men’s basketball vs. Iowa State — December 12, 2019Saturday night at 7:00 — August 10th 2007 — Twins vs. Texas — Johan Santana strikes out 17Sunday night at 7:00 — April 12, 2010 — Twins vs. Boston — Twins first-ever game at Target Fieldlast_img read more

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