Radiogenic Heat Production in the Cretaceous Sediments of Yola Arm of Nigeria Benue Trough: Implications for Thermal History and Hydrocarbon Generation

ArticleinJournal of Applied Sciences 5:696-701 · April 2005with39 Reads
DOI: 10.3923/jas.2005.696.701

    Abstract

    Yola Arm is an east-west extension of the upper Benue Trough of Nigeria
    with Cretaceous sediments of Albian to Senonian ages. Thirteen samples
    which are mainly sandstone, shale, mudstone, clay, siltstone, limestone
    and coal were collected from six different geological units namely: Bima
    Sandstone (BS), Yolde Formation (YF), Dukul Formation (DF), Sukuliye
    Formation (SF), Numanhan Formation (NF) and Lamja Sandstone (LS). This
    is to determine their radioactive heat production and implications for
    thermal history and hydrocarbon generation. The result shows that
    concentration and rate of heat production of 40K,
    232Th and238U in the samples varies widely with
    lithologies and stratigraphic intervals. Three groups of total Heat
    Production (HP) were identified and designated as low (LHP), moderate
    (MHP) and high (HHP). The LHP includes sandstones of BS, limestone of DF
    and coal of LS with total heat production of <750 pW kg-1.
    Clay of BS, siltstone of YF, limestone of SF and NF and sandstone of LS
    belong to MHP with total heat production of between 750 and 1500 pW
    kg-1. Shale of YF, SF and NF with total heat production of
    >1500 pW kg-1 belong to HHP. The HHP group corresponds to
    shale units at different ages in the study area and are the possible
    source rock for hydrocarbon generation. The total heat production
    studies have suggested that the Cretaceous sediments experienced complex
    temperature history with at least two sudden thermal pulses. They could
    have been related to Cretaceous synsedimentary volcanism or to the
    emplacement of the basaltic pluton.