Unusual soft-sediment deformation structures in the Maritimes Basin, Canada: Possible seismic origin

作者：Snyder Morgan E^*; Waldron John W F

来源：Sedimentary Geology, 2016, 344: 145-159.

DOI：10.1016/j.sedgeo.2016.03.014

• Nova Scotia
• Carboniferous
• Horton Group
• Soft-sediment deformation
• Seismites

Soft-sediment deformation structures provide information on the early deformation history of sedimentary rocks. In the Mississippian Horton Group of the Windsor-Kennetcook subbasin of the Maritimes Basin in Nova Scotia, soft-sediment deformation structures include well-known features like load structures, neptunian dykes, and an intraformational breccia. More unusual features include sedimentary boudins, upward-convex bulb structures, and unique structures here termed microbasins. Microbasins are geometrically similar to minibasins associated with salt tectonics, but about three orders of magnitude smaller. These deformation structures formed when primary stratification was in a weakened state due to liquidization of sediment. Two types of structures exist: those that formed at the sediment surface and those that formed later, during burial. The triggering mechanism for soft-sediment deformation structures in the Horton Group was likely seismicity and overpressured conditions. A strong preferred orientation of soft-sediment structures oriented NW-SE is attributed to dextral strike-slip on the E-W Minas Fault Zone. Seismicity associated with movement along faults associated with the Minas Fault Zone could have induced liquidization of sediment.

• 出版日期2016-10