| Peer-Reviewed

Determination of the Physical Properties of Near Surface Layers of Omerulu Area, Nigeria, Using Seismic Refraction Method

Received: 5 April 2017     Accepted: 20 April 2017     Published: 24 October 2017
Views:       Downloads:
Abstract

Seismic refraction method is a geophysical technique used to study physical properties of the subsurface such as layer thicknesses, travel times and velocities of seismic signals through the layers. The process of turning seismic refraction data to useful information involves use of first arrival times and offsets. In this study, the near surface investigation of the physical properties of the unconsolidated and consolidated layers was carried out in Omerelu, Rivers State of Nigeria. Omerelu lies between latitude 050 08’N and 050 13’N and longitude 060 51’E and 060 58’E. Previous investigations were based on refection method in which the near surface effect caused misalignment in the deeper horizons observed in the final stack of the reflection data. This problem was solved by running a seismic refraction survey over the area. The study involved identification of points at which data would be acquired to give a good overview of the area under consideration. Twelve sampling points were picked with a grid of approximately 4 × 4 km. A 100 m line with two source points at each end was cleared at each data acquisition point after which the coordinates were taken using Leica Total station (TC 1203 survey equipment). Seismic signals were recorded using OYO McSeis 160M coupled with a 12-geophone harness along with a blasting unit. Upsphere processing software was used to plot time - offset graphs to determine the velocities of the unconsolidated and consolidated layers. The intercept times were also graphically obtained and used to determine the thickness of the unconsolidated layer. Results show that the thickness of unconsolidated/weathered layer in the study area varies between 12.25 and 13.60 m, while the velocities of the unconsolidated and the consolidated layers vary between 500 – 550 m/s and 1790 – 1875 m/s respectively. The results obtained when applied to the reflection data, were able to resolve the static problems; thereby increasing and improving the quality of data available on the lithology of the study area.

Published in International Journal of Oil, Gas and Coal Engineering (Volume 5, Issue 5)
DOI 10.11648/j.ogce.20170505.15
Page(s) 97-115
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2017. Published by Science Publishing Group

Keywords

Arrival Times, Offsets, Misalignment, Intercept Time, Seismic Refraction Data, Consolidated Layers, Unconsolidated Layers

References
[1] Ajani, O. O, Fajemiroye, J. A and Odumosu O. A., 2013. Study of near surface layers of Omerelu area using low velocity layer (LVL) method. International Journal of Developmental Sciences IJDS. 2 (1), 131-139.
[2] Asseez, L. O., 1976. Review of the stratigraphy, sedimentation and structure of the Niger Delta. Kogbe C. A. Rock review (Nig,) Ltd, Pub. 311-324.
[3] Chaubey, A. K., 2000. Seismic Reflection and Refraction Methods. Cambridge University Press, England: 214-221.
[4] Dobrin, M. B. 1985. Introduction to geophysical prospecting. McGraw-Hill Book Co, Inc., New York:100 – 110, 148–151, 222–226.
[5] Edge, A G, and Laby., T H., 1931. The principles and practice of geophysical exploration: Cambridge University Press, London, 339-340.
[6] Enikanselu, P. A., 2008. “Geophysical Seismic Refraction and Uphole Survey Analysis of Weathered Layer Characteristics in the “Mono” Field, North Western Niger Delta” in Proceedings of National Workshop on Geophysical Seismic Analysis, Delta State, Nigeria, pp. 1–7.
[7] Espey, H. R., 1981. Seismic field techniques. Geotran Inc, Los Angeles: VI 24-27.
[8] Galitzin. mines. edu., 2002. Exploration Geophysics: Refraction Seismic Notes. 2002: 1–55.
[9] Hawkins, L. V., 1961. The Reciprocal method of routine shallow seismic refraction investigations: Geophysics, 26, 806–819.
[10] Jones, I. F., 2013. Tutorial: Seismic response to strong vertical velocity change, first break, 31(6), 79-90.
[11] Krawczyk, C. M., Polon, U., and Beilecke, T., 2013. Shear - wave reflection seismics as a valuable tool for near - surface urban applications. The Leading Edge, 32, 256-263.
[12] Lankston, R. W., 1990. High-resolution refraction seismic data acquisition and interpretation, in Ward, S. H., editor, Geotechnical and Environmental Geophysics, Volume 1: Review and Tutorial: Society of Exploration Geophysicists: 344-390.
[13] Lowrie W,. 2007. Fundamentals of Geophysics, Cambridge University Press, England: 83 – 98, 145–147.
[14] Nettleton, L. L., 1940. Geophysical prospecting for oil: McGraw-Hill Book Co., New York: 444.
[15] Okwueze E., 1996. Shell Intensive Training Programme (Geophysics: Seismic methods lectures): 24–46.
[16] Palmer, D., 1980. The generalized reciprocal method seismic refraction interpretation. Soc of Explo. Geophys.
[17] Uko, E. T., Emudlanughe, J. E and Eze, C. L., 2016. Comparison of the characteristics of Low Velocity Layer (LVL) in the Mangrove swamp and in upper flood plain Environment in the Niger Delta using Seismic refraction method. Journal of Geology and Geophysics 5: 248. 1-8.
[18] Telford, W. M., L. P. Geldart, and R E Sheriff., 1990. Applied Geophysics, 2nd ed., Cambridge University Press.
[19] Weber, K. J., 1971. Sedimentological aspects of oil fields in the Niger Delta 50: 559–576.
[20] Wojciech Czuba (2017). 3-D Seismic tomographic modeling of the crustal structure of Northwestern Svalbard based on deep seismic sounding. Geophys J Int 208(1): 508–520.
Cite This Article
  • APA Style

    Olowofela Joseph Adeniyi, Akinyemi Olukayode Dewunmi, Odumosu Olutayo, Ajani Olumide Oyewale. (2017). Determination of the Physical Properties of Near Surface Layers of Omerulu Area, Nigeria, Using Seismic Refraction Method. International Journal of Oil, Gas and Coal Engineering, 5(5), 97-115. https://doi.org/10.11648/j.ogce.20170505.15

    Copy | Download

    ACS Style

    Olowofela Joseph Adeniyi; Akinyemi Olukayode Dewunmi; Odumosu Olutayo; Ajani Olumide Oyewale. Determination of the Physical Properties of Near Surface Layers of Omerulu Area, Nigeria, Using Seismic Refraction Method. Int. J. Oil Gas Coal Eng. 2017, 5(5), 97-115. doi: 10.11648/j.ogce.20170505.15

    Copy | Download

    AMA Style

    Olowofela Joseph Adeniyi, Akinyemi Olukayode Dewunmi, Odumosu Olutayo, Ajani Olumide Oyewale. Determination of the Physical Properties of Near Surface Layers of Omerulu Area, Nigeria, Using Seismic Refraction Method. Int J Oil Gas Coal Eng. 2017;5(5):97-115. doi: 10.11648/j.ogce.20170505.15

    Copy | Download

  • @article{10.11648/j.ogce.20170505.15,
      author = {Olowofela Joseph Adeniyi and Akinyemi Olukayode Dewunmi and Odumosu Olutayo and Ajani Olumide Oyewale},
      title = {Determination of the Physical Properties of Near Surface Layers of Omerulu Area, Nigeria, Using Seismic Refraction Method},
      journal = {International Journal of Oil, Gas and Coal Engineering},
      volume = {5},
      number = {5},
      pages = {97-115},
      doi = {10.11648/j.ogce.20170505.15},
      url = {https://doi.org/10.11648/j.ogce.20170505.15},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ogce.20170505.15},
      abstract = {Seismic refraction method is a geophysical technique used to study physical properties of the subsurface such as layer thicknesses, travel times and velocities of seismic signals through the layers. The process of turning seismic refraction data to useful information involves use of first arrival times and offsets. In this study, the near surface investigation of the physical properties of the unconsolidated and consolidated layers was carried out in Omerelu, Rivers State of Nigeria. Omerelu lies between latitude 050 08’N and 050 13’N and longitude 060 51’E and 060 58’E. Previous investigations were based on refection method in which the near surface effect caused misalignment in the deeper horizons observed in the final stack of the reflection data. This problem was solved by running a seismic refraction survey over the area. The study involved identification of points at which data would be acquired to give a good overview of the area under consideration. Twelve sampling points were picked with a grid of approximately 4 × 4 km. A 100 m line with two source points at each end was cleared at each data acquisition point after which the coordinates were taken using Leica Total station (TC 1203 survey equipment). Seismic signals were recorded using OYO McSeis 160M coupled with a 12-geophone harness along with a blasting unit. Upsphere processing software was used to plot time - offset graphs to determine the velocities of the unconsolidated and consolidated layers. The intercept times were also graphically obtained and used to determine the thickness of the unconsolidated layer. Results show that the thickness of unconsolidated/weathered layer in the study area varies between 12.25 and 13.60 m, while the velocities of the unconsolidated and the consolidated layers vary between 500 – 550 m/s and 1790 – 1875 m/s respectively. The results obtained when applied to the reflection data, were able to resolve the static problems; thereby increasing and improving the quality of data available on the lithology of the study area.},
     year = {2017}
    }
    

    Copy | Download

  • TY  - JOUR
    T1  - Determination of the Physical Properties of Near Surface Layers of Omerulu Area, Nigeria, Using Seismic Refraction Method
    AU  - Olowofela Joseph Adeniyi
    AU  - Akinyemi Olukayode Dewunmi
    AU  - Odumosu Olutayo
    AU  - Ajani Olumide Oyewale
    Y1  - 2017/10/24
    PY  - 2017
    N1  - https://doi.org/10.11648/j.ogce.20170505.15
    DO  - 10.11648/j.ogce.20170505.15
    T2  - International Journal of Oil, Gas and Coal Engineering
    JF  - International Journal of Oil, Gas and Coal Engineering
    JO  - International Journal of Oil, Gas and Coal Engineering
    SP  - 97
    EP  - 115
    PB  - Science Publishing Group
    SN  - 2376-7677
    UR  - https://doi.org/10.11648/j.ogce.20170505.15
    AB  - Seismic refraction method is a geophysical technique used to study physical properties of the subsurface such as layer thicknesses, travel times and velocities of seismic signals through the layers. The process of turning seismic refraction data to useful information involves use of first arrival times and offsets. In this study, the near surface investigation of the physical properties of the unconsolidated and consolidated layers was carried out in Omerelu, Rivers State of Nigeria. Omerelu lies between latitude 050 08’N and 050 13’N and longitude 060 51’E and 060 58’E. Previous investigations were based on refection method in which the near surface effect caused misalignment in the deeper horizons observed in the final stack of the reflection data. This problem was solved by running a seismic refraction survey over the area. The study involved identification of points at which data would be acquired to give a good overview of the area under consideration. Twelve sampling points were picked with a grid of approximately 4 × 4 km. A 100 m line with two source points at each end was cleared at each data acquisition point after which the coordinates were taken using Leica Total station (TC 1203 survey equipment). Seismic signals were recorded using OYO McSeis 160M coupled with a 12-geophone harness along with a blasting unit. Upsphere processing software was used to plot time - offset graphs to determine the velocities of the unconsolidated and consolidated layers. The intercept times were also graphically obtained and used to determine the thickness of the unconsolidated layer. Results show that the thickness of unconsolidated/weathered layer in the study area varies between 12.25 and 13.60 m, while the velocities of the unconsolidated and the consolidated layers vary between 500 – 550 m/s and 1790 – 1875 m/s respectively. The results obtained when applied to the reflection data, were able to resolve the static problems; thereby increasing and improving the quality of data available on the lithology of the study area.
    VL  - 5
    IS  - 5
    ER  - 

    Copy | Download

Author Information
  • Department of Physics, Federal University of Agriculture (FUNAAB), Abeokuta, Nigeria

  • Department of Physics, Federal University of Agriculture (FUNAAB), Abeokuta, Nigeria

  • Exploration Unit, United Geophysical Company, Warri, Nigeria

  • Department of Physics and Solar Energy, Bowen University, Iwo, Nigeria

  • Sections