Exceptionally well exposed normal faults within the Solite Quarry of the Dan River rift basin range in length from a few millimetres to a few metres and are possibly the smallest visible faults studied to date. Displacement is greatest at or near the center of isolated faults and decreases toward the fault tips. Relay structures form between closely overlapping faults. The distribution of fault sizes in the study area follows a power-law (fractal) relation, and the maximum observed displacement scales linearly with fault length. The new fault data extend the global data set to more than eight orders of magnitude of fault length and indicate that there is no significant change in displacement geometry and the linear lengthdisplacement scaling relation between small and large faults.
Virtually the entire Late Triassic and earliest Jurassic age section of the early Mesozoic Newark continental rift basin has been recovered in over 6770 m of continuous core as part of the Newark Basin Coring Project (NBCP). Core was collected using an offset drilling method at seven sites in the central part of the basin. The cores span most of the fluvial Stockton Formation, all of the lacustrine Lockatong and Passaic formations, the Orange Mountain Basalt, and nearly all of the lacustrine Feltville Formation. The cores allow for the first time the full Triassic-age part of the Newark basin stratigraphic sequence to be described in detail. This includes the gray, purple, and red, mostly fluvial Stockton Formation as well as the 53 members that make up the lacustrine Lockatong (mostly gray and black) and Passaic (mostly red) formations. The nearly 25% overlap zones between each of the stratigraphically adjacent cores are used to test lateral correlations in detail, scale the cores to one another, and combine them in a 4660-m-thick composite section. This composite shows that the entire post-Stockton sedimentary section consists of a hierarchy of sedimentary cycles, thought to be of Milankovitch climate cycle origin. Lithostratigraphic and magnetostratigraphic correlations between core overlap zones and outcrops demonstrate that the in-dividual sedimentary cycles can be traced essentially basinwide. The agreement between the cyclostratigraphy and magnetostratigraphy shows both the cycles and the polarity boundaries to be isochronous horizons. Detailed analysis of the Newark basin shows that high-resolution cyclostratigraphy is possible in lacustrine, primarily red-bed rift sequences and provides a fine-scale framework for global correlations and an understanding of continental tropical climate change. Data Repository item 9601 contains additional material related to this article.
STRATIGRAPHIC AND CYCLOSTRATIGRAPHIC NOMENCLATURENewark basin strata have been studied for over 130 yr (e.g., Redfield, 1856). The cur-Figure 1. A. Reconstruction of Pangea for the middle Norian showing the zone of early Mesozoic rifting (shaded) and the preserved basins of the Newark Supergroup (black). Continental positions based on Kent et al. (1995) and Witte et al. (1991) and Pangea reconstruction based on Scotese (1986). B. Early Mesozoic rift basins of eastern North America (based on Olsen et al., 1989).
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