RATES OF DISPLACEMENT AND LATERAL CONTINUITY OF THE BATON ROUGE FAULT SYSTEM SEGMENTS: EVIDENCE OF HOLOCENE DISPLACEMENT NEAR THE EAST ORLEANS LAND BRIDGE?

The Baton Rouge Fault System (BRFS) is a series of deep-seated, east-trending normal faults that define the present-day northern physiographic boundary of the Pontchartrain Basin. Analysis of a 2D industry seismic dataset in Lake Pontchartrain and two, 3D industry seismic datasets in Lake Borgne, revealed three faults (two identified as part of BRFS) that may show lateral continuity beneath the East Orleans Land Bridge with three Lake Borgne Fault System (LBFS) segments. The South Point Fault of the BRFS, partially visible in 2D data, is suggested to be actively displacing Holocene strata causing infrastructure damage to the Highway 11 Bridge. Shallow stratigraphic data was collected to determine displacement in Holocene strata across the deeper identified faults as well as to determine whether there is structural continuity between the BRFS and LBFS. A grid of shallow, high-resolution Chirp seismic lines and 22 shallow vibracores were collected for analysis of shallow strata. Stratigraphic cross sections may show displacement of the Pleistocene-Holocene contact when compared to Chirp seismic data. Dating of C¹⁴ in organics and shells from core samples will be used to correlate strata and contacts.