_version_ 1867170956520194048
author Kepezhinskas, Pavel A
Sorokina, Nadia A
Mamontova, Svetlana A
Savichev, Alex T
author_facet Kepezhinskas, Pavel A
Sorokina, Nadia A
Mamontova, Svetlana A
Savichev, Alex T
collection Datos científicos de ciencias marinas y ambientales
contents Hole 504B is located in Panama Basin approximately 200 km south of the Costa Rica Rift within a tectonically undisturbed oceanic crust formed at the Costa Rica Rift spreading center. The hole was drilled in several Deep Sea Drilling Project (DSDP)/Ocean Drilling Program (ODP) legs, including ODP Leg 140. The 378.9 m of core drilled at Hole 504B during Leg 140 continues the dike complex recovered previously during DSDP Leg 83. All the rocks drilled during Leg 140 are fragments of variably metamorphosed dikes composed of olivine-plagioclase-clinopyroxene-, olivine-plagioclase-, and olivine-plagioclase-clinopyroxene-spinel-bearing basalts. We report results of determination of rare earth elements (REE) and large-ion lithophile (LIL) elements in 28 representative samples from the major units of the Hole 504B dike complex. Analyzed samples display relatively uniform REE patterns with only a slight difference in the extent of light REE depletion. LIL elements show large variations independent from other incompatible (Zr and Y), compatible (Cr, Ni, Co), and rare earth elements. Observed REE variations indicate that metamorphism has changed LIL distribution, but has not affected REE patterns. Variable REE depletions are believed to represent original magmatic characteristics of the Costa Rica Rift oceanic crust. LIL distribution favors Ba redistribution due to the fluid-rock interaction in the lower oceanic crust. REE systematics define various degree of depletion in Leg 140 diabase dikes consistent with their derivation from a variably depleted MORB-type source.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_805898
institution PANGAEA
language en
publishDate 1995
publisher PANGAEA
record_format pangaea
spellingShingle (Table 2) Representative major and trace element analyses of diabase dikes of ODP Hole 140-504B
Kepezhinskas, Pavel A
Sorokina, Nadia A
Mamontova, Svetlana A
Savichev, Alex T
140-504B; Alteration; Aluminium oxide; Atomic absorption spectrometry (AAS); Barium; Calcium oxide; Calculated; Cerium; Chromium; Cobalt; DEPTH, sediment/rock; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Elements, total; Erbium; Europium; Gadolinium; Inductively coupled plasma atomic emission spectroscope (ICP-AES); Iron oxide, Fe2O3; Joides Resolution; Lanthanum; Leg140; Lithologic unit/sequence; Magnesium number; Magnesium oxide; Manganese oxide; Neodymium; Nickel; North Pacific Ocean; Ocean Drilling Program; ODP; Phosphorus pentoxide; Potassium oxide; Samarium; Sample code/label; Silicon dioxide; Sodium oxide; Strontium; Titanium dioxide; Vanadium; X-ray fluorescence (XRF); Ytterbium; Zirconium/Yttrium ratio
Hole 504B is located in Panama Basin approximately 200 km south of the Costa Rica Rift within a tectonically undisturbed oceanic crust formed at the Costa Rica Rift spreading center. The hole was drilled in several Deep Sea Drilling Project (DSDP)/Ocean Drilling Program (ODP) legs, including ODP Leg 140. The 378.9 m of core drilled at Hole 504B during Leg 140 continues the dike complex recovered previously during DSDP Leg 83. All the rocks drilled during Leg 140 are fragments of variably metamorphosed dikes composed of olivine-plagioclase-clinopyroxene-, olivine-plagioclase-, and olivine-plagioclase-clinopyroxene-spinel-bearing basalts. We report results of determination of rare earth elements (REE) and large-ion lithophile (LIL) elements in 28 representative samples from the major units of the Hole 504B dike complex. Analyzed samples display relatively uniform REE patterns with only a slight difference in the extent of light REE depletion. LIL elements show large variations independent from other incompatible (Zr and Y), compatible (Cr, Ni, Co), and rare earth elements. Observed REE variations indicate that metamorphism has changed LIL distribution, but has not affected REE patterns. Variable REE depletions are believed to represent original magmatic characteristics of the Costa Rica Rift oceanic crust. LIL distribution favors Ba redistribution due to the fluid-rock interaction in the lower oceanic crust. REE systematics define various degree of depletion in Leg 140 diabase dikes consistent with their derivation from a variably depleted MORB-type source.
title (Table 2) Representative major and trace element analyses of diabase dikes of ODP Hole 140-504B
topic 140-504B; Alteration; Aluminium oxide; Atomic absorption spectrometry (AAS); Barium; Calcium oxide; Calculated; Cerium; Chromium; Cobalt; DEPTH, sediment/rock; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Elements, total; Erbium; Europium; Gadolinium; Inductively coupled plasma atomic emission spectroscope (ICP-AES); Iron oxide, Fe2O3; Joides Resolution; Lanthanum; Leg140; Lithologic unit/sequence; Magnesium number; Magnesium oxide; Manganese oxide; Neodymium; Nickel; North Pacific Ocean; Ocean Drilling Program; ODP; Phosphorus pentoxide; Potassium oxide; Samarium; Sample code/label; Silicon dioxide; Sodium oxide; Strontium; Titanium dioxide; Vanadium; X-ray fluorescence (XRF); Ytterbium; Zirconium/Yttrium ratio
url https://doi.org/10.1594/PANGAEA.805898