Mineralogy, geochemistry and selected chemical formulas of sediments from ODP Holes 161-986B and 161-977A
Cobertura |
MEDIAN LATITUDE: 36.118500 * MEDIAN LONGITUDE: -3.134030 * SOUTH-BOUND LATITUDE: 36.031700 * WEST-BOUND LONGITUDE: -4.312780 * NORTH-BOUND LATITUDE: 36.205300 * EAST-BOUND LONGITUDE: -1.955280 * DATE/TIME START: 1995-05-21T09:00:00 * DATE/TIME END: 1995-06-15T14:30:00 |
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Data(s) |
16/01/1999
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Resumo |
Upper Miocene to Pleistocene hemipelagites and resedimented facies recovered at Holes 976B and 977A (Leg 161) in the Alboran Basin consist mainly of biogenic and detrital components, with a minor contribution of neoformed mineral phases. Diagenetic processes have not obliterated the primary deposition signal, and therefore detrital components (quartz, feldspar, detrital dolomite, rock fragments, and clays) provide information about source rocks and provenances. No major bulk or clay mineralogy differences were recognized between resedimented and hemipelagic facies; in fact, similar mineral assemblages in both types of facies suggest common source rocks. However, mineral abundance fluctuations can be related to climate variations and tectonic factors, as the main controls of sediment fill of this basin. A marked increase in smectites in Messinian sediments suggests an extensive development of soils during that time, probably favored by the alternation of wet and dry climate episodes and the relative aridification of the Mediterranean borderlands. A notable increase in detrital components suggests a sea-level fall and/or tectonic uplift during the late Pliocene. The significant increase in detrital dolomite in the uppermost Pliocene deposits suggests the uplift of dolomite-rich rocks as source areas. Mineral components in Pleistocene sediments indicate increasing tectonic stability, and clay-mineral fluctuations during the Pleistocene can be related not only to tectonic events, but also to alternating cooling and warming periods. |
Formato |
application/zip, 9 datasets |
Identificador |
https://doi.pangaea.de/10.1594/PANGAEA.805348 doi:10.1594/PANGAEA.805348 |
Idioma(s) |
en |
Publicador |
PANGAEA |
Direitos |
CC-BY: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted |
Fonte |
Supplement to: Martinez-Ruiz, Francisca C; Comas, Maria C; Alonso, Belen (1999): Mineral associations and geochemical indicators in upper Miocene to Pleistocene sediments in the Alboran Basin. In: Zahn, R; Comas, MC; Klaus, A (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 161, 1-16, doi:10.2973/odp.proc.sr.161.203.1999 |
Palavras-Chave | #Al(IV); Al(VI); Aluminium (IV); Aluminium (VI); Ba; Barium; Ca; Cal; Calcite; Calcium; Calculated based on oxygen number; Chl; Chlorite; Co; Cobalt; Copper; Cu; Depth; DEPTH, sediment/rock; Dol; Dolomite; Event; Fe; ICP-MS, Inductively coupled plasma - mass spectrometry; Ill; Illite; interlayer cations; Iron 2+ and 3+; K; Kaolinite; Kln; Label; Lead; Magnesium; mbsf; Mg; Ni; Nickel; Ocean Drilling Program; octahedral cations; ODP; ODP sample designation; Pb; Phyllosilicate; Potassium; Quartz; Qz; Rare-earth elements; Rb; REE; Rubidium; Sample code/label; Si; Silicon; Sme; Smectite; Sr; Strontium; Sum; Th; Thorium; Ti; Titanium; U; Uranium; V; Vanadium; X-ray diffractometry (Philips PW1710); Zinc; Zirconium; Zn; Zr |
Tipo |
Dataset |