Fluid Inclusions and Genetic Aspects of the Damara Orogen

  • H.-J. Behr
  • E. E. Horn
  • H. Porada
Conference paper

Abstract

The relationships of fluid systems and orogenetic processes have been investigated in metasediments from the Khomas Trough of the southern Damara Orogen and from the margin of the southern platform. Fluid inclusion measurements revealed the existence of a high-saline system originating from playa sequences of the initial graben and rifting stage, and a low-saline system derived from metapelites of the geosynclinal fill.

The high-saline system had been stored, since diagenesis in sparite horizons and were liberated when hot crystalline nappes from the Khomas Trough were thrust onto the playa sequence of the Duruchaus Formation. Excess pore pressure built up by aquathermal pressuring caused a mechanical mobilisation of the carbonate (sparite) horizons and strongly influenced the nappe tectonics along the southern margin of the Damara Orogen.

Profound hydrothermal metasomatic alterations of the country rock, crystallisation of voluminous quartz-carbonate masses, locally with giant crystals, and the formation of stratiform copper mineralisations are further consequences of the high-saline fluid circulation.

Dewatering and dehydration processes resulting in specific structures characterise the geosynclinal meta-pelites and their low-saline fluid system. Still preserved fluids allow a reconstruction of the P/T history and the process of uplift after the peak of metamorphism.

Keywords

Calcite Shale Dehydration Pyrite Pleistocene 

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Copyright information

© Springer-Verlag Berlin Heidelberg 1983

Authors and Affiliations

  • H.-J. Behr
    • 1
  • E. E. Horn
    • 1
  • H. Porada
    • 1
  1. 1.Geologisch-Paläontologisches InstitutGöttingenGermany

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