Ishikawa, Tsuyoshi & Nakamura, Eizo (1992) Boron isotope geochemistry of the oceanic crust from DSDP/ODP Hole 504B, Geochimica et Cosmochimica Acta, 56, 1633-1639, doi: 10.1016/0016-7037(92)90230-G. < 20200221094909-267444 > pub

Map on Earth or stone. Places and analyses are shown.

  • abstract:

    Boron contents and boron isotopic compositions were determined for the uppermost 1.3 km section of typical 6.2 Ma oceanic crust from DSDP/ODP Hole 504B, Costa Rica Rift, Galapagos Spreading Center. Both the boron content and the δ11B value in the oceanic crust are controlled by two types of alteration: (1) low-temperature alteration (0 to 60°C; Zones I and II) and (2) high-temperature hydrothermal alteration (200 to 400°C; Zones III and IV). Basalts subjected to the low-temperature alteration are characterized by their relatively high boron contents (0.69 to 19.3 ppm) and high δ11B values (+2.2 to +10.6%.), indicating uptake of boron into secondary phases in equilibrium with seawater or evolved seawater. Hydrothermally altered basalts contain less abundant boron (0.17 to 0.52 ppm) and relatively constant δ11B values (−0.1 to +1.0%.). Although basalts from the upper part of these hydrothermal zones (< 1300 mbsf) show equilibrated boron content and δ11B value with aqueous fluid, effective leaching of boron from basalt is predominant in the lower part (>1300 mbsf). Original boron content and δ11B value of the Hole 504B MORB were 0.35 ppm and +0.2%., respectively. The present data provide fundamental information in understanding of the distribution of boron and boron isotopes in the oceanic crust.

  • doi: 10.1016/0016-7037(92)90230-G
  • modified at 17 h ago


(a) B_procedures of Nakamura et al. (1992) on TIMS Thermo-Fisher MAT261
Tixhr 706529138 thumb 2-1 112-115 #234 < 20160830143049-796925 >pub
  • place: N1°13′37.9″, W83°43′48.7″ more
  • classification: volcanic:basaltic
  • physical-form: thin section
  • status: (unknown)
  • description: DSDP/ODP Hole 504B, Costa Rica Rift, Galapagos Spreading Center; Zone 1 fine-grained ol-pl-cpx phyric basalt
  • modified at 2020-05-07
Tixhr298462816 thumb 8-5 33-36 #563 < 20160830143151-532965 >pub
  • place: N1°13′37.9″, W83°43′48.7″ more
  • classification: volcanic:basaltic
  • physical-form: thin section
  • status: (unknown)
  • description: DSDP/ODP Hole 504B, Costa Rica Rift, Galapagos Spreading Center; Zone 1 medium-grained ol-pl-cpx phyric basalt
  • modified at 2020-05-07
Tixhr163440927 thumb 52-2 81-83 #1016 < 20160830143250-760601 >pub
  • place: N1°13′37.2″, W83°43′48.0″ more
  • classification: volcanic:basaltic
  • physical-form: thin section
  • status: (unknown)
  • description: DSDP/ODP Hole 504B, Costa Rica Rift, Galapagos Spreading Center; Zone 2 medium-grained ol-pl-cpx phyric basalt
  • modified at 2020-05-07
name box-type global-id
binder of Boron isotope geochemistry of the oceanic crust from DSDP/ODP Hole 504B pub container 20200221094937-727336
name latitude longitude global-id
DSDP/ODP Hole 504B pub 1.2272 N 83.7302 W 20200221100707-681080
DSDP/ODP Hole 504B pub 1.2272 N 83.7302 W 20200221100447-947659
DSDP/ODP Hole 504B pub 1.2270 N 83.7300 W 20200221100936-839371
name device size global-id
2-1 112-115 pub TIMS Thermo-Fisher MAT261 4 20200221101411-088555
8-5 33-36 pub TIMS Thermo-Fisher MAT261 4 20200221101706-049116
52-2 81-83 pub TIMS Thermo-Fisher MAT261 4 20200221101953-092076
name spots global-id
caption ID assembly stone
Table 1. B content, d11B and d11O of basalts from Hole 504B pub 20200221103342-426152 B-O (Ishikawa, 1992) 3
manual
  • name
  • Ishikawa, Tsuyoshi
  • Nakamura, Eizo