4. Structure of the Peru Forearc from Multichannel Seismic-reflection Data
نویسندگان
چکیده
Multichannel seismic-reflection data collected on the Peru margin as part of Leg 112 of the Ocean Drilling Program predrilling site survey define some tectonic and sedimentary features of the Lima and Yaquina basins. A narrow accretionary prism is imaged at the toe of the trench slope in both areas. Landward of the accretionary prism is a transition zone that may be underlain by older accreted material and/or attenuated continental crust. Lima and Yaquina basins are underlain by disrupted reflectors that were interpreted as continental crust. The sedimentary section is characterized by lens-shaped seismic sequences that are cut by numerous, small-displacement, normal faults.
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