A study of geomorphologic features of land surface, drainage patterns, and subsurface geology, as they appear on LANDSAT-1 imagery, suggests that the area of the present Delmarva Peninsula has been undergoing tectonic evolution at least since early Tertiary times. Several NE-SW and NW-SE trending lineaments can be correlated with the subsurface basement faults and surface geomorphologic features. Several other lineaments, however, do not seem to correspond to any known surface or subsurface features. Lack of correlation also exists for several surficial features and for several subsurface features which are not apparent on the LANDSAT-1 imagery. One of the major tectonic events that has been taking place for a considerable period of time is southeastward or eastward tilt of the Peninsula. This is evident in the regional drainage patterns of present-day streams, coastal geomorphology, the distribution of subsurface geologic units and surfaces of unconformities. The evidence for significant regional vertical movements that affected not only the area of the Peninsula but also other parts of the Coastal Plain is provided by two major unconformities between Eocene and Middle Miocene and between Late Miocene and Pleistocene, respectively. It is beleived that the area was continuously or intermittently uplifted during these hiatuses. A conceptual model for the block-fault origin of the Atlantic Continental Terrace appears to be compatible with the fault systems and other structural features observed on the Peninsula. Assuming that the model, which relates marginal faulting to the impingement of oceanic fracture zones, is correct and that rifting at the Mid-Atlantic Ridge is presently occurring it can be concluded that the tectonic evolution of the Delmarva Mid-Altantic Ridge is presently occurring, it can be concluded that the tectonic evolution of the Delmarva Peninsula is still in progress.

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  • Corporate Authors:

    American Society of Photogrammetry

    105 North Virginia Avenue
    Falls Church, VA  United States  22046
  • Authors:
    • Spoljaric, N
    • Jordan, R R
    • Sheridan, R E
  • Publication Date: 1976-8

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Filing Info

  • Accession Number: 00139730
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Sep 21 1976 12:00AM