Micromotion is the daily tiny vibration of the earth ’ s surface. Micromotional exploration can use the surface wave information of micro motion to study the shallow structure of underground media. In this study, we collected microtremor data at 68 stations in the Middle-Lower Yangtze Metallogenic Belt (MLYMB) and determined the resonant frequency and obtained the distribution of sedimentary thickness in this area by using H/V spectral ratio. According to the results of H/V, the sedimentary layer in the basin is thick, and the predominant frequency of the basin is 0.05 - 0.1 Hz. There are no obvious lateral changes in the impedance interface between bedrock and sedimentary layer in this area. The basement of Tongling, Anqing and Luzhou mining areas and their adjacent areas is Kongling-Dongling type basement, which is composed of a set of metamorphic core complex. The predominant frequency is 0.05 - 0.1 Hz. The sedimentary thickness gradually thinned from 3800 m in the west to 2100 m in the East. Moreover, this article used SPAC (spatial autocorrelation) method to obtain the S-wave velocity structure of the mining area near Luzong. The SPAC method reveals that the depth of the interface between the loose sediments and the volcanic rocks is about 600 m in the study area near the Luzhou mining area in the Middle-Lower Yangtze Metallogenic Belt, and the average depth of the interface between the volcanic rock section and the intrusive complex section is about 1000 m. The thickness of the intrusive rock is more than 2500 m. Tourmaline is developed in the interior of the intrusive rock, which may have better exploration value.
Mao, J.W., Wang, Y.T., Lehmann, B., et al. (2006) Molybdenite Re-Os and Albite 40Ar/39Ar Dating of Cu-Au-Mo and Magnetite Porphyry Systems in the Yangtze River Valley and Metallogenic Implications. Ore Geology Reviews, 29, 307-324. https://doi.org/10.1016/j.oregeorev.2005.11.001
Jiang, G.M., Zhang, G.B., Lv, Q.T., et al. (2013) 3-D Velocity Model beneath the Middle-Lower Yangtze River and Its Implication to the Deep Geodynamics. Tectonophysics, 606, 36-47. https://doi.org/10.1016/j.tecto.2013.03.026
Liang, W., Gong, W., Wei, S., et al. (2015) The Worth and the Significance of Port in Economic Integration Development Model: A Case Study on Yangtze River Economic Belt of China. Open Journal of Social Sciences, 3, 44-55. https://doi.org/10.4236/jss.2015.312005
Yu, X.G., Wang, L., Yang, Q.K., et al. (2015) Background of the Yangtze River Economic Belt Development Strategy and Geography Interpretation of Its Innovative Development. Progress in Geography, 34, 1368-1376.
Li, S.G. (2001) Deep Tectonic Setting of Mesozoic Magmatic Rocks and Cu Fe Metallogenic Belt in the Middle and Lower Reaches of the Yangtze River. Geology of Anhui Province, No. 2, 118-122.
Xu, Y., Lv, Q.T., Zhang, W.B., et al. (2015) 3D S-Wave Velocity Structure of the Middle and Lower Yangtze Metallogenic Belt and Its Constraints on Deep Processes. Acta Geophysica Sinica, 58, 4373-4387.
Xue, H.M., Wu, M.A. and Ma, F. (2014) Deep Rock Association and Alteration Mineralization of Luzong Volcanic Basin Revealed by Lzsd of Luzong Scientific Drilling. Chinese Geophysical Society.
Nogoshi, M. and Igarashi, T. (1971) On the Amplitude Characteristics of Microtremor (Part 2) Zisin (Journal of the Seismological Society of Japan. 2nd ser.). https://doi.org/10.4294/zisin1948.24.1_26
Nakamura, Y. (1989) A Method for Dynamic Characteristics Estimation of the Subsurface Using Microtremor on the Ground Surface. Quarterly Report of RTRI, 30, 25-33.
Nakamura, Y. (2000) Clear Identification of Fundamental Idea of Nakamura’s Technique and Its Applications. 12th World Conference on Earthquake Engineering, Auckland, 30 January-4 February 2000, 8.
Field, E.H. and Jacob, K. (1993) The Theoretical Response of Sedimentary Layers to Ambient Seismic Noise. Geophysical Research Letters, 20, 2925-2928. https://doi.org/10.1029/93GL03054
Lermo, J. and Arcia, C.G. (1994) Are Microtremors Useful in Site Response Evaluation. Bulletin of the Seismological Society of America, 84, 1350-1364.
Mucciarelli, M. (1998) Reliability and Applicability of Nakamura’s Technique Using Micro Tremors: An Experimental Approach. Journal of Earthquake Engineering, 2, 625-638. https://doi.org/10.1080/13632469809350337
Parolai, S., Bormann, P. and Milkereit, C. (2001) Assessment of the Natural Frequency of the Sedimentary Cover in the Cologne Area (Germany) Using Noise Measurements. Journal of Earthquake Engineering, 5, 541-564. https://doi.org/10.1080/13632460109350405
Haghshenas, E., Bard, P.Y., Theodulidis, N., et al. (2008) Empirical Evaluation of Microtremor H/V Spectral Ratio. Bulletin of Earthquake Engineering, 6, 75-108. https://doi.org/10.1007/s10518-007-9058-x
Rincon, O., Shakoor, A. and Ocampo, M. (2016) Investigating the Reliability of H/V Spectral Ratio and Image Entropy for Quantifying the Degree of Disintegration of Weak Rocks. Engineering Geology, 207, 115-128. https://doi.org/10.1016/j.enggeo.2016.04.020
Bignardi, S. (2017) The Uncertainty of Estimating the Thickness of Soft Sediment with the HVSR Method: A Computational Point of View on Weak Lateral Variations. Journal of Applied Geophysics, 145, 28-38. https://doi.org/10.1016/j.jappgeo.2017.07.017
Seht, I.V. and Wohlenberg, J. (1999) Microtremor Measurements Used to Map Thickness of Soft Sediment. Bulletin of the Seismological Society of America, 89, 250-259. https://doi.org/10.1785/BSSA0890010250
Chen, Q.F., Liu, L.B., Wang, W.J., et al. (2008) Site Effects on Earthquake Ground Motion Based on Microtremor Measurements for Metropolitan Beijing. Chinese Science Bulletin, 52, 2229-2235.
Sukumaran, P., Parvez, I.A., Sant, D.A., et al. (2011) Profiling of Late Tertiary Early Quaternary Surface in the Lower Reaches of Narmada Valley Using Microtremors. Journal of Asian Earth Sciences, 41, 325-334. https://doi.org/10.1016/j.jseaes.2011.02.011
Guo, Z., Aydin, A. and Kuszmaul, J.S. (2014) Microtremor Recordings in Northern Mississippi. Engineering Geology, 179, 146-157. https://doi.org/10.1016/j.enggeo.2014.07.001
Yilar, E., Baise, L.G. and Ebel, J.E. (2017) Using H/V Measurements to Determine Depth to Bedrock and Vs30 in Boston, Massachusetts. Engineering Geology, 217, 12-22. https://doi.org/10.1016/j.enggeo.2016.12.002
Aki, K. (1957) Space and Time Spectra of Stationary Stochastic Waves, with Special Reference to Microtremors. Bulletin of the Earthquake Research Institute, 35, 415-456.
Henstridge, J.D. (1979) A Signal Processing Method for Circular Arrays. Geophysics, 44, 179-184. https://doi.org/10.1190/1.1440959
Ling, S. and Okada, H. (1993) An Extended Use of the Spatial Autocorrelation Method for the Estimation of Geological Structure Using Microtremors. Proceedings of the 89th SEGJ Conference, Japanese, 44-48. (In Japanese)
Chavez-Garcia, F.J., Rodriguez, M. and Stephenson, W.R. (2005) An Alternative Approach to the Analysis of Microtremors-Exploiting Stationarity of Noise. Bulletin of the Seismological Society of America, 95, 277-293. https://doi.org/10.1785/0120030179
Kudo, K. (2002) Site-Specific Issues for Strong Ground Motions during the Kocaeli, Turkey, Earthquake of 17 August 1999, as Inferred from Array Observations of Microtremors and Aftershocks. Bulletin of the Seismological Society of America, 92, 448-465. https://doi.org/10.1785/0120000812
Apostolidis, P., Raptakis, D., Roumelioti, Z., et al. (2004) Determination of s-Wave Velocity Structure Using Microtremors and Spac Method Applied in Thessaloniki (Greece). Soil Dynamics & Earthquake Engineering, 24, 49-67. https://doi.org/10.1016/j.soildyn.2003.09.001
Asten, M.W., Askan, A., Ekincioglu, E., et al. (2014) Site Characterization in North-Western Turkey Based on SPAC and HVSR Analysis of Microtremor Noise. Exploration Geophysics, 45, 74-85. https://doi.org/10.1071/EG12026
Bignardi, S., Mantovani, A. and Abu Zeid, N. (2016) OpenHVSR: Imaging the Subsurface 2D/3D Elastic Properties through Multiple HVSR Modeling and Inversion. Computers & Geosciences, 93, 103-113. https://doi.org/10.1016/j.cageo.2016.05.009
Liu, G., Dong, S.W., Ma, L.C., et al. (2016) Basement and Mineralization in the Middle and Lower Reaches of the Yangtze River. Acta Geologica Sinica, 90, 2258-2275.