(Table 1) Chemical composition of segregations and groundmass seperates of ODP Leg 135 samples


Autoria(s): Bloomer, Sherman H
Cobertura

MEDIAN LATITUDE: -19.480000 * MEDIAN LONGITUDE: -177.110000 * SOUTH-BOUND LATITUDE: -20.709000 * WEST-BOUND LONGITUDE: -177.862000 * NORTH-BOUND LATITUDE: -18.501000 * EAST-BOUND LONGITUDE: -176.500000 * DATE/TIME START: 1990-12-23T20:39:00 * DATE/TIME END: 1991-01-24T00:40:00 * MINIMUM ELEVATION: -2917.0 m * MAXIMUM ELEVATION: -2469.0 m

Data(s)

01/11/1994

Resumo

Concentrations of dark-colored, highly vesicular, quench-textured mesostasis occur commonly in volcanic rocks drilled in the Lau Basin during Leg 135. These segregations occur as veins, patches, and vesicle linings in rocks with 49%-54% SiO2. The segregations are depleted in Mg, Ca, Al, Sc, Ni, and Cr and enriched in Ti, Ba, Y, and Zr compared to the groundmass with which they occur. Many of the segregations are unusually enriched in copper. The elemental variations show that the segregations are residual liquids produced by 12%-55% crystallization of plagioclase and clinopyroxene, with minor olivine, opaques, or orthopyroxene from the groundmass melt. The liquids forming the segregations are mobilized and emplaced in earlier formed vesicles during the rapid crystallization of the groundmass. The dominant process in this mobilization and emplacement is volatile exsolution from crystallizing melts constrained by a rigid crystalline framework. This exsolution produces significant overpressures within the late-stage melts; the overpressure drives the residual melts through the walls of the older vesicles, along planes of weakness, and into voids. This mechanism is consistent with the occurrence of bimodal vesicle populations in many of the host lavas.

Formato

text/tab-separated-values, 926 data points

Identificador

https://doi.pangaea.de/10.1594/PANGAEA.793499

doi:10.1594/PANGAEA.793499

Idioma(s)

en

Publicador

PANGAEA

Direitos

CC-BY: Creative Commons Attribution 3.0 Unported

Access constraints: unrestricted

Fonte

Supplement to: Bloomer, Sherman H (1994): Origin of segregation vesicles in volcanic rocks from the Lau Basin, Leg 135. In: Hawkins, J; Parson, L; Allan, J; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 135, 615-623, doi:10.2973/odp.proc.sr.135.127.1994

Palavras-Chave #135-834B; 135-835B; 135-836B; 135-839B; Aluminium oxide; Barium; Barium/Zirconium ratio; Calcium oxide; Chromium; Clinopyroxene; Copper; DRILL; Drilling/drill rig; Elevation of event; Event label; Iron oxide, Fe2O3; Joides Resolution; Latitude of event; Leg135; Liquid fraction; Lithologic unit/sequence; Longitude of event; Magnesium oxide; Manganese oxide; Mass; Mesostasis; Nickel; Ocean Drilling Program; ODP; ODP sample designation; Olivine; Opaque minerals; Orthopyroxene; Oxides; Phosphorus; Phosphorus oxide; Plagioclase; Potassium oxide; Pseudonodosaria symmetrica; Sample code/label; Sample comment; Scandium; Silicon dioxide; Sodium oxide; South Pacific Ocean; Strontium; Sum; Titanium/Zirconium ratio; Titanium oxide; Type; Vanadium; Vesicle; Yttrium; Yttrium/Zirconium ratio; Zinc; Zirconium
Tipo

Dataset