[
    {
        "id": "osp-13792",
        "type": "article-journal",
        "title": "Delineation of Weathered Layer Using Uphole and Surface Seismic Refraction Methods in Parts of Niger Delta, Nigeria",
        "author": [
            {
                "family": "Aka",
                "given": "Mfoniso U."
            },
            {
                "family": "Agbasi",
                "given": "Okechukwu Ebuka"
            }
        ],
        "URL": "https://omanscience.com/en/articles/delineation-of-weathered-layer-using-uphole-and-surface-seismic-refraction-methods-in-parts-of-niger-delta-nigeria",
        "language": "en",
        "issued": {
            "date-parts": [
                [
                    2021
                ]
            ]
        },
        "container-title": "Sultan Qaboos University Journal for Science",
        "volume": "26",
        "issue": "1",
        "page": "58-66",
        "DOI": "10.53539/squjs.vol26iss1pp58-66",
        "publisher": "Sultan Qaboos University",
        "ISSN": "2308-3921",
        "abstract": "Uphole and surface seismic refraction surveys were carried out in parts of the Niger Delta, Nigeria, to delineate weathering thickness and velocity associated with aweathered layer. A total of twelve uphole and surface seismic refraction surveyswere shot, computed and analyzed. The velocity of the uphole seismic refraction ranged from 344.8 to 680.3 m/s with a thickness of 5.45 to 13.35 m. Surface seismic refraction ranged from 326.6 to 670.2 m/s and 4.30 to 12.0 m, respectively. The average velocity and thickness ranged from 559.6 to 548.0 m/s and 9.43 to 8.63m with differences of 11.6 m/s and 0.83 m respectively. The VW/VS ratios ranged from 0.955 to 1.059. This indicates that the uphole velocity is higher than the surface refraction velocity leading to low VW/VS values. This is a direct experimental proof of a low velocity zone, confirming the weathered nature of the area. The results of both refraction methods are reliable; the differences in surface refraction values are due to shot point offsets. Based on these findings, it is recommended that shots for seismic surveys should be located above 15.0 m in the area to delineate the effects associated with weathered layers to ensure that will be competent to withstand engineering structures."
    }
]