Oil spill in the Gulf of Mexico and spiral vortex   总被引：2，自引：2，他引：0  

ZHENG Quanan  ZHAO Qing  Nan Walker  LI Chunyan 《海洋学报(英文版)》2010,29(4):1-2

<正>Drilling rig Deepwater Horizon in the Gulf of Mexico,leased by BP PLC from Transocean Ltd.,exploded and caught on fire on April 20,2010.The drilling location is at some 50 miles(80 kilometers)off the coast of Louisiana  相似文献   

Chemical and genetic characterization of the ungrouped pallasite Lieksa     

Emily M. Chiappe  Richard D. Ash  Arto Luttinen  Sari Lukkari  Jukka Kuva  Connor D. Hilton  Richard J. Walker 《Meteoritics & planetary science》2023,58(12):1747-1759

The meteorite Lieksa was found in 2017 in Löpönvaara, Finland, and later donated to the Finnish Museum of Natural History. Here, we report siderophile element concentrations, genetic isotopic data, and a metal–silicate segregation age for the meteorite. The ~280 g Lieksa is ~80% metal and ~20% silicate and oxide inclusions by volume, with the inclusions consisting primarily of Fe-rich olivine. Due to Lieksa's silicate content, coupled with a texture characterized by metal enclosing the silicates, it has been classified as a pallasite. Lieksa's olivine and bulk chemical characteristics are distinct from those of the known pallasite and iron meteorite groups, consistent with its classification as ungrouped. The meteorite exhibits a flat, chondrite-normalized highly siderophile element pattern, consistent with an origin as an early crystallization product from a metallic melt with chondritic relative abundances. Molybdenum, Ru, and ¹⁸³W isotopic data indicate that Lieksa formed in the non-carbonaceous (NC) domain of the solar nebula. Radiogenic ¹⁸²W abundances for Lieksa yield a model metal–silicate segregation age of 1.5 ± 0.8 Myr after calcium-aluminum-rich inclusion formation, which is within the range established for other NC-type pallasite and iron meteorite parent bodies.  相似文献