2010 Alum


Olamide Dada

Olamide Dada


Years participated in RESESS:
2010


An Overview

Preliminary analysis of a high resolution seismic profile acquired near Marianna, Arkansas, for earthquake hazard assessment

Academic Affiliation: Senior, University Of Oklahoma, Geology
Science Research Mentors: Rob Williams, Bill Stephenson, Jack Odum, USGS
Writing & Communication Mentor: Otina Fox, UNAVCO


Biography

Olamide Dada attends the University of Oklahoma. He goes by "Dada" and calls Houston home. Dada was turned on to geophysics by his professor, Katie Keranen, at the University of Oklahoma, and joined a USGS field crew in June, 2010, to get seismic reflection of the crust in the New Madrid Seismic Zone in Arkansas. Interviewed by ABC news, Dada became the new face of the USGS and RESESS on local television. Dada is interested in politics, socializing, and family. During his RESESS internship in Boulder he confounded his cohorts by stating that he was allergic to hiking.


Abstract

Linear trends of mid-Holocene, earthquake-induced sand blows near Marianna, Arkansas, prompted the USGS in June, 2010, to look for the related faults using new high-resolution, P-wave seismic reflection profiles in this area. The field area is located in east-central Arkansas about 75 km southwest of Memphis, Tennessee, and 80 km south of the southwestern end of the familiar New Madrid seismicity trend. Previous studies of the sand blows indicate that they were produced 5,000 to 7,000 years ago by large earthquakes, and were similar in magnitude (M7+) to the1811 and 1812 New Madrid earthquakes. This site adds to a growing list of potentially active faults in the New Madrid seismicity trend.

Two parallel, east-west-oriented, 5-km-long profiles were acquired across the northwest-southeast sand blow trend, with 5- and 10-m geophone and Minivibe source spacing, respectively. Preliminary processing and interpretation of the data reveals several prominent and well-known marker reflections at the top of the Paleozoic and Cretaceous sections, as well as several strong, coherent reflections within the Tertiary section. In one profile there are two west-up vertical discontinuities in the Paleozoic reflection that are strongly suggestive of faulting. The western-most fault displacement is larger and appears to have recurrent motion with about 40 m of uplift on the Paleozoic reflection and about 20 m of uplift on Eocene reflections. These fault displacements are typical of those seen in other seismic profiles in the Mississippi embayment. Additional data processing and analysis are needed to clarify whether these faults reach the base of the Quaternary section at about 50-m depth.