XRF analyses of volcanic rocks from Leg 152 by laboratories in Edinburgh and Copenhagen: implications for the mobility of yttrium and other elements during alteration

Larsen, Lotte Melchior; Fitton, J. Godfrey; Bailey, J.C.; Kystol, Jørgen

doi:10.2973/odp.proc.sr.152.246.1998

Cited by 5 publications

(4 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As shown by L.M. Larsen et al (1998b), the accordance between the major element analyses carried out in Copenhagen and Edinburgh is excellent, ensuring full compatibility between the present major el-ement data set and that for the Leg 152 samples obtained in Edinburgh .…”

Section: Upper Miocene-pleistocenesupporting

confidence: 63%

See 1 more Smart Citation

Composition of volcanic rocks from the Southeast Greenland margin, Leg 163: major and trace element geochemistry

Larsen¹,

Fitton²,

Saunders³

1999

Proceedings of the Ocean Drilling Program

Self Cite

View full text Add to dashboard Cite

During Leg 163, in the Southeast Greenland margin, drilling penetrated a thick succession of volcanic rocks that erupted during breakup of the North Atlantic in the early Tertiary. Samples recovered during Leg 163 supplement the samples recovered during Leg 152 from the transect across the volcanic margin at 63°N. During Leg 163, drilling at Site 989 was intended to recover the oldest part of the continental prebreakup series, and drilling at Site 990 was intended to penetrate the transition zone from synbreakup, compositionally variable volcanic products, to postbreakup volcanics with a limited compositional range and a depleted chemical character similar to mid-ocean-ridge basalts (oceanic character). All the lava flows recovered from Sites 989 and 990, however, have an oceanic chemical character with low contents of incompatible elements and high contents of Sc. A dikelet from Site 990 and a previously drilled dike from Site 917 are likewise oceanic. We consider that the two drilled lava flows from Site 989 were emplaced after breakup despite their setting on the innermost part of the continental margin.The succession at Site 990 consists of 13 units of lava flow that show a slight compositional development upsection with Mg# decreasing from ~62 to ~49. This variation is within the limits known from the slightly younger oceanic succession drilled earlier at Site 918, in which the variation is thought to reflect fractionation in magma chambers in the oceanic crust. The reestablishment of magma chambers after the breakup must have been achieved during the interval that the short, undrilled lava succession between uppermost Site 917 and lowermost Site 990 was deposited.All the lava flows from Sites 989 and 990, except perhaps one (Unit 989-1), are crustally contaminated, as judged from their high Ba/Zr (>0.42) ratios. The two dikes appear to be uncontaminated. The contamination most likely took place in magma chambers in the young oceanic rift, which, at this early stage of spreading, could still have contained fragments of continental crust. Most lavas were probably erupted within the rift and flowed subaerially away from it toward the edge of the continent. The dikes show that lateral injection of magma into the continental crust also took place without resulting in crustal contamination. The oceanic lava flows at Site 989 on the innermost margin have probably been erupted through such laterally injected dikes.The primary magma for the postbreakup rocks is estimated to have contained ~18% MgO. After fractionation of 30 mol% olivine (Fo 91-82 ), it shifted to gabbro fractionation, and the magmas started to erupt. The modal composition of the gabbroic cumulate is 8% olivine (Fo 82-74 ), 50% plagioclase (An 76-66 ), and 42% clinopyroxene (Fs 9-15 ). The erupted oceanic magmas are produced by <24 mol% gabbro fractionation, with an average of 14%. Thus, geochemical modeling indicates that the oceanic crust is composed of olivine cumulates (30%), gabbro cumulates (14%), and melts (lava flows and dikes, 56%), which is...

show abstract

Section: Upper Miocene-pleistocenesupporting

confidence: 63%

“…There is also no evidence in the Leg 163 samples for mobility of yttrium, as found in the basalts from Site 918 (L.M. Larsen et al, 1998b).…”

Section: Resultsmentioning

confidence: 87%

Composition of volcanic rocks from the Southeast Greenland margin, Leg 163: major and trace element geochemistry

Larsen¹,

Fitton²,

Saunders³

1999

Proceedings of the Ocean Drilling Program

Self Cite

View full text Add to dashboard Cite

show abstract

“…6) by Winchester and Floyd (1977) was used for the determination of the magma origin of the altered ashes showing that the samples plot in two groups: the majority of bentonites fall within the alkali basalt field, whereas x1 has a trachytic composition. Yttrium is generally considered to be as immobile as the other three elements used in the diagram, but under certain weathering conditions this element can be mobilized during alteration (e.g., Larsen et al, 1998, Christidis, 1998 or it can be concentrated in biogenic phosphate layers (Egger et al, 2000). This can lead to a shift of the position of the samples in the plot towards higher Nb/Y ratios.…”

Section: Discussionmentioning

confidence: 99%

Geochemical study of lower Eocene volcanic ash layers from the Alpine Anthering Formation, Austria.

2003

View full text Add to dashboard Cite

“…5. The XRF values differ from aquifer rocks, with the two samples taken from tuffaceous sandstone and tuff capable of influencing the groundwater (Larsen et al, 1998;Maria & Hermes, 2001).…”

Section: Harker Diagrammentioning

confidence: 98%

Groundwater Chemistry Characterization in the South and Southeast Merapi Volcano, Indonesia

Hendrayana

Harijoko

Riyanto

et al. 2022

IJG

View full text Add to dashboard Cite

Merapi Volcano, which differs from volcanoes in other climates due to its location on the Indonesian Maritime Continent influenced by ENSO, ICTZ, and Moonsons, plays an essential role as a source of groundwater for the surrounding population. Some problems associated with groundwater in Mount Merapi are high utilization compared to other volcanoes worldwide, changes in land use, pollution, and its lowering table. Therefore, this study aims to compare the hydrogeological characteristics and aquifer systems of the southern and southeastern parts of Merapi Volcano. The hydrogeological characteristics were obtained from geological mapping, surface and subsurface, as well as rock XRF tests. Meanwhile, the hydrogeochemical characterization was determined through chemical data using the Trilinear Piper, Kurlov, Fingerprint, Composition, and Harker Diagram methods. The results of the Trilinear Piper, Kurlov, Fingerprint, and Composition Diagram methods show that Mount Merapi has 3, 7, 4, and 2 types of patterns different from other volcanoes in the world. On the other hand, the Harker diagram has the same pattern of Mg-Ca and Mg-Na as several other volcanoes. In conclusion, the hydrostratigraphy in the southern part of the volcano, consists of aquifuge, aquiclude, and aquifer, while in the southeast, there are aquitards of volcanic sandstone and tuff.

show abstract

XRF analyses of volcanic rocks from Leg 152 by laboratories in Edinburgh and Copenhagen: implications for the mobility of yttrium and other elements during alteration

Cited by 5 publications

References 6 publications

Composition of volcanic rocks from the Southeast Greenland margin, Leg 163: major and trace element geochemistry

Composition of volcanic rocks from the Southeast Greenland margin, Leg 163: major and trace element geochemistry

Geochemical study of lower Eocene volcanic ash layers from the Alpine Anthering Formation, Austria.

Groundwater Chemistry Characterization in the South and Southeast Merapi Volcano, Indonesia

Contact Info

Product

Resources

About