Abstract

The Golden Meadow Fault Zone (located between the Terrebonne and Barataria basins near Golden Meadow, Louisiana) is an array of growth faults which occur in deltaic Quaternary sediments and poorly lithified material (Crone and Wheeler, 2000) (Fig. 1). The fault zone occurs in the Lafourche delta, which is the youngest abandoned major delta lobe of the Mississippi River and is entering a late transgressive state (Coleman et al., 1998; Roberts, 1997). While there appears to be little movement in these faults, they can significantly affect the delicate land on a local scale, such as causing wetland loss, decreasing natural hurricane and flood protection, and damaging infrastructure (Culpepper et al., 2019; Gagliano, 2003).

Examination of the fault zone integrated cone penetrometer tests (CPTs), geospatial analysis, mathematical vector analysis, Compressed high intensity radar pulse (CHIRP) 2D seismic data, and water well log data in order to refine techniques and characterize the presence of these growth faults in the study area. It was found that faults affect the hydrologic nature of the area by possibly predetermining drainage patterns, creating preferential spots for lakes, influencing river course, and increasing water depth by the creation of sagging. Geotechnical analysis showed a notable change in the mechanical properties of the soil in the vicinity of the projected surface location of the southernmost, antithetic fault (Fig. 2). Geospatial analysis revealed subbasin and minibasin location is closely related to drainage patterns and associated fault influence or location.

Conclusions derived from this statewide project will assist the Louisiana Master Plan in picking sites of critical infrastructure and environmental restoration efforts along the deltaic coast of the state (Kulp, 2018).