کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5783192 1637947 2017 58 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The behavior of chalcophile elements during magmatic differentiation as observed in Kilauea Iki lava lake, Hawaii
ترجمه فارسی عنوان
رفتار عناصر کلوکوفیل در هنگام تمایز مغناطیسی در دریاچه چیلاوا اکی لاوا، هاوایی
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات ژئوشیمی و پترولوژی
چکیده انگلیسی
We quantify the behavior of Cu, Ga, Ge, As, Mo, Ag, Cd, In, Sn, Sb, W, Tl, Pb, and Bi during the differentiation of a picritic magma in the Kilauea Iki lava lake, Hawaii, using whole rock and glass differentiation trends, as well as partition coefficients in Cu-rich sulfide blebs and minerals. Such data allow us to constrain the partitioning behavior of these elements between sulfide and silicate melts, as well as the chalcophile element characteristics of the mantle source of the Kilauea lavas. Nearly all of the elements are generally incompatible on a whole-rock scale, with concentrations increasing exponentially below ∼6 wt% MgO. However, in-situ laser ablation data reveal that Cu, Ag, Bi, Cd, In, Pb, and Sn are chalcophile; As, Ge, Sb, and Tl are weakly chalcophile to lithophile; and Mo, Ga, and W are lithophile. The average Dsulfide/silicate melt values are: DAg = 1252 ± 1201 (2SD), DBi = 663 ± 576, DCd = 380 ± 566, DIn = 40 ± 34, DPb = 34 ± 18, DSn = 5.3 ± 3.6, DAs = 2.4 ± 7.6, DGe = 1.6 ± 1.4, DSb = 1.3 ± 1.5, DTl = 1.1 ± 1.7, DMo = 0.56 ± 0.6, DGa = 0.10 ± 0.3, and DW = 0.11 ± 0.1. These findings are consistent with experimental partitioning studies and observations of Ni-rich sulfide liquid in mid-ocean ridge basalts (MORB), despite the different compositions of the KI sulfides. The KI glasses and whole rocks are enriched in As, Ag, Sb, W, and Bi, relative to elements of similar compatibility (as established by abundances in MORB), mimicking enrichments found in basalts from the Manus back arc basin (Jenner et al., 2012) and the upper continental crust (UCC). These enrichments suggest the presence of terrigenous sediments in the Kilauea mantle source. The KI source is calculated to be a mixture of depleted MORB mantle (DMM) and 10-20% recycled crust composed of MORB and minor terrigenous sediments.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Geochimica et Cosmochimica Acta - Volume 210, 1 August 2017, Pages 71-96
نویسندگان
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