Welcome to the Web page of Dr. Hanan Mahdi

University of Arkansas at Little Rock (UALR)


 

Professional Information

  • Title: Research Assistant Professor
    • BS, University of Baghdad
    • MS, University of Baghdad
    • PhD, St. Louis University

Contact Information

 picture of Dr. Mahdi

Professional Career

PROFESSIONAL EXPERIENCE

SCIENTIFIC RESEARCH

Seismology

Currently, I'm a member of a research team conducting a comprehensive geological and geophysical investigation to identify and characterize specific features related to historic or prehistoric earthquakes near the southern terminus of the New Madrid Seismic Zone in eastern Arkansas. Recently conducted aerial and field surveys revealed the existence of liquefaction and linear features as far as south of Marianna, Arkansas. The study is divided into three parts. First, field surveys in the study area will be conducted to locate features potentially generated by earthquakes. Second, trench, log, sample, and document the selected features. Third, ground penetrating radar geophysical surveys will be conducted on the trenched features to derive, if possible, their characteristic signature. The possibility of transferring this signature to other localities will be investigated.

Research and development in support of monitoring a Comprehensive Test Ban Treaty (CTBT). The program includes seismic signal enhancement, detection and onset time estimation, better estimate of surface wave magnitude, and characterization of seismic instrumentation.

I have worked on developing advanced methods utilizing broadband, three-component seismic arrays to better estimate surface-wave magnitude from small regional events. The ultimate objective of this work is to improve discriminant reliability of smaller events by providing stable yield estimate under low signal-to noise conditions. This is a characteristic of smaller nuclear explosions recorded at regional distances.

Studying Scattering and multi-pathing effect on surface wave propagation at regional distances in central Asia. The study uses broadband digital seismic data recorded by Kyrghyzia network operated by IRIS Joint seismic program since 1991. Single station and array processing techniques are both merged and utilized.

Studying spectral characteristics of earthquakes and explosions recorded at regional and teleseismic distances for the purpose of discriminating small earthquakes and explosions. One aspect of this analysis is studying the spectral amplitudes of array beam of both earthquake and explosion to examine the effect of different azimuths and stacking phase velocity on surface wave amplitude spectrum. This is part of a study using array processing methods to enhance signals in the 0.01 to 0.2 Hz band

Analysis of the lateral and regional variation of seismic wave velocity in the crust and upper mantle using seismic surface wave data and utilizing inversion procedure to derive velocity models and to correlate them with geological and tectonic setting of the region. This analysis has been applied to derive velocity models for Western United States, Africa, central Asia, and Lopnor, the Chinese nuclear test site.

Studying the regional and lateral variation of anelasticity to understand the evolution of the continental crust and upper mantle using seismic surface wave attenuation. This investigation includes measurement of anelastic attenuation coefficients and inversion of these measurements to derive anelastic structural model and correlate it with the tectonic and thermal history of a specific region.

Shallow Geophysics

Laboratory experiments, an outdoor test bed, and theoretical modeling have been used to investigate the potential of using ground penetrating radar (GPR) to detect water leaks in the underground distribution system. Leaks not only waste precious natural resources, but they also create substantial damage to the transportation system within urban and suburban environments. Surface geophysical methods are non-invasive, trenchless tools used to characterize the physical properties of the subsurface material. This characterization is then used to interpret the geologic and hydrogeologic conditions of the subsurface. Many geophysical techniques have been suggested as candidates for detecting leakage, including GPR, acoustic devices, gas sampling devices and pressure waves detectors. GPR is a reflection technique, which uses high frequency electromagnetic waves to acquire subsurface information. GPR responds to changes in electrical properties, which are a function of soil and rock material and moisture content. A series of laboratory experiments were conducted to validate the effectiveness of GPR technology in detecting water leakage in metal and PVC pipes. Results obtained so far indicate that GPR is effective in detecting water leaks and contaminant plumes. An outdoor test bed is currently under construction in collaboration with Central Arkansas Water to simulate and detect water leaks using the GPR technique. Pipes that are commonly used for water distribution in the city of Little Rock are to be used for testing. The test bed will be constructed using soil matrial that is representative of the region. Advanced digital signal processing will be implemented to enhance the anomalies.

PUBLIC EDUCATION

Support the Arkansas Center for Earthquake Education and Technology Transfer (ACEETT) to accomplish its public education mission by participating in the following activities: 1. provide earthquake workshops promoting seismic safety, mitigation, education and planning for professional groups. 2. Disseminate earthquake information related to seismic education and technical training needs of the state. 3. Provide an enhanced internet seismic and technical database and educational resources for students and general public. 4. Provide assistance to professional education organizations, and scientific and technical groups concerning their needs for seismic education and technology transfer.

PUBLICATIONS

Sallomy, J. T. and H. H. Al-Khatib (1986a). Basement tectonics in the Al-Salman area, SW desert, Iraq, Arabian J. Sc. Eng. 11, 77-85.

Sallomy, J. T. and H. H. Al-Khatib (1986b). Analysis of gravity and magnetic data in the study of the structure and tectonics of the Arar area, SW desert, Iraq,Arabian J. Sc. Eng.11, 213-224.

Al-Khatib, H.H. and B.J.Mitchell (1989). Lateral variation of anelasticity in the upper mantle beneath the western United States from Rayleigh wave attenuation, EOS, American Geophysical Union,70,401. (abstract).

Al-Khatib, H. H. and B. J. Mitchell (1991). Upper mantle unelasticity and tectonic evolution of the western United States, J. Geophys. Res. 96,1829-1846.

Mellors, R.J., H.H. Al-Khatib, H.J. Al-Shukri, G.L. Pavlis, M.W. Hamburger, and F.L. Vernon (1992). Preliminary Analysis of Data from the Kirghizia Telemetered Broadband Seismic Network,EOS, American Geophysical Union,(abstract).

Pavlis, G, H. Al-Shukri, H.H. Mahdi, D. Repin, F. Vernon (1994). JSP arrays and networks in Central Asia, IRIS Newsletter,9-12.

Pavlis, G.L., H.H. Mahdi, and F.L. Vernon (1994). Surface wave propagation in central Asia; observations of scattering and multipathing with the Kerghys broadband array, (abstract) 1994 AFOSR annual meeting.

Romer, S.A., H.H.Mahdi, H.J. Al-Shukri(1995). Preliminary surface wave analysis of data from Kirghizia Broadband seismic network, (abstract),1995 MAS meeting.

Mahdi,H.H., and G.L.Pavlis (1995). Crustal and uppermost mantle structure beneath Eastern Tien Shan from Broadband surface wave data, (abstract),GSA 1995 meeting.

Pavlis,G.L., and H.H.Mahdi (1995). The spatial stability of Rayleigh wave amplitudes and path dependent propagation characteristics of central Asia, (abstract) 1995 AFOSR annual meeting.

Mahdi,H.H., and G.L.Pavlis (1995). Spatial stability of Rayleigh wave amplitude and path dependent stacking capabilities of the Kyrghystan Broadband Network, (abstract) 1995 AGU fall meeting.

Pavlis,G.L., H.H.Mahdi (1996). surface wave propagation in central Asia: Observations of scattering and multipathing with the Krygyz Broadband Array, J. Geophys.Res.,101,8437-8455.

Mahdi,H.H., and G.L.Pavlis (1996). Lateral velocity variations in the crust and upper mantle beneath the Tien Shan from surface wave: Implications for tectonic and dynamic processes, (abstract) 1996 SSA annual meeting.

Al-Shukri, H.J., H.H. Mahdi, and K.D. Hutchenson (1997). Evaluation of the F-statistics Onset-time Estimator, ENSCO Inc. Final Technical Report, ARS 97-069.

Al-Shukri, H.J., H.H. Mahdi, and K.D. Hutchenson (1997). Signal Detection Using Covariance Matrix of Array Data,(abstract) AGU Fall Meeting.

Mahdi,H.H., and G.L.Pavlis (1998). Lateral velocity variations in the crust and upper mantle beneath the Tien Shan from surface wave: Implications for tectonic and dynamic processes. J. Geophys. Res., 103, 2693 -2703.

Mahdi, H.H., and K.D. Hutchenson (1998). Test and Evaluation of the Long Period Surface Wave Multi-signal Processor, ENSCO Inc. Final Technical Report, ARS-98.

Al-Shukri, HJ, Lemmer, R., Connelly, J, Mahdi, H, and Egan, M. (2000). Paleoseismic Features in the Southern Terminus of the New Madrid Seismic Zone, EOS, Transaction of the America Geophysical Union, 81, No.48, PF857 (abstract).

Hanan H. Mahdi, Haydar J. Al-Shukri, Robert E. Lemmer, Jeffrey B. Connelly, and Michael B. E. Bograd (2001). Investigation of possible paleoliquefaction features in Mississippi, Mississippi Academy of Science Annual Meeting.

Robert E. Lemmer, Haydar J. Al-Shukri, Jeffrey B. Connelly, and Hanan H. Mahdi (2001). Liquefaction and other possible seismogenic features southwest of the New Madrid seismic zone in eastern Arkansas, Preceding of the Mississippi Academy of Science Annual Meeting.

Al-Shukri, H.J., Lemmer, R.E., Mahdi, H.H., and Connelly, J.B.(2001). spatial and temporal characteristics of paleoseismic features in the southern terminus of the new madrid seismic zone in eastern Arkansas,(abstract), Seismological Society of America annual meeting, San Francisco, CA.

Connelly, Jeffrey B., Hanan H. Mahdi, Robert E. Lemmer, Marilyn Egan, and Haydar J. Al-Shukri,(2001). paleoseismic features in the southern part of the new madrid seismic zone, Arkansas Academy of Science Annual Meeting.(abstract).

Sami Eyuboglu, Hanan H. Mahdi, , and Haydar J. Al-Shukri,(2003). Detection of Water Leaks using Ground Penetrating Radar, the 3rd International Conference on Applied Geophysics. (abstract).

Al-Shukri, HJ, Hanan Mahdi, Martitia P. Tuttle and (2003). Spatial and Temporal Characteristics of Paleoseismic Features in the Southern Terminus of the New Madrid Seismic Zone in Eastern Arkansas, United States Geological Survey, 03HQGR0050

Al-Shukri, HJ, Hanan Mahdi, Dawood Mahmood, and Nawal Alridha (2004) Current Status and Future Planning for Earthquake Monitoring in Iraq, Gulf Seismic Forum, United Arab Emirates

Sami Eyuboglu, Hanan Mahdi, and Haydar Al-Shukri (2004). Ground Penetrating Radar: A Geophysical Tool to Search for Water on Mars, IEEE Trans Geoscience and Remote Sensing.

Al-Shukri, HJ, and Hanan Mahdi (2004). Detection of water leak using Ground Penetrating Radar, Central Arkansas Water, Little Rock, Arkansas

Sami Eyuboglu, Hanan Mahdi, and Haydar Al-Shukri (2004). Detection of Water Leak Using Ground Penetrating Radar, Geophysics.

Al-Shukri, HJ, Hanan Mahdi, and Dawood Mahmood (2005). Rebuilding Iraqi Seismic Data Center and Earthquake Network, Gulf Seismic Forum-II, Al-Ain, UAE.

Mahdi, Hanan, Martitia P. Tuttle, and Haydar Al-Shukri (2005). 3-d imaging of earthquake-induced liquefaction features with ground penetrating radar , Seismological Society of America, Eastern Section Annual Meeting, Memphis, TN.

Martitia P. Tuttle, Hanan Mahdi, and Haydar Al-Shukri (2005). Very Large Earthquakes Centered Southwest of the New Madrid Seismic Zone 5,000-7,000 Years Ago, Seismological Society of America, Eastern Section Annual Meeting.

Al-Shukri, Haydar, Sami Eyuboglu, and Hanan Mahdi (2005). Water leak detection by using ground penetrating radar, synthetic simulation and four-dimensional visualization, American Geophysical Union Annual Meeting.

Al-Shukri Haydar J., Robert E. Lemmer, Hanan H. Mahdi, and Jeffrey B. Connelly (2005). Spatial and Temporal Characteristics of Paleoseismic Features in the Southern Terminus of the New Madrid Seismic Zone in Eastern Arkansas, Seismo. Research Lett.. 76, 502-511.

Mahdi, H.H., (2006). Spatial stability of Rayliegh wave amplitude and path dependent stacking capabilities of the Kyrghystan Broadband Network, (a paper in preparation).

TEACHING

  Courses