The Taconides of western New Jersey: New evidence from the Jutland Klippe: Summary
INTRODUCTION AND REGIONAL SETTING Because of their peculiar color, exotic lithologies, and geologic setting, the predominantly pelitic rocks that are found between Jutland and Clinton, western New Jersey (Fig. 1), have attracted considerable attention (Weller, 1903; Bayley and others, 1914; Stose, 1930, 1946; Kay, 1941; Lewis and Kummel, 1940; Willard, 1943; Ethington and others, 1958; McBrlde, 1962; Neuman and Dodge, 1964; Markewicz, 1964 (unpub. map), Barnett, 1965; Kasabach, 1966; Drake, 1969, 1970; Rodgers, 1971; and Zen, 1972). Yet, surprisingly little detailed work has been done in the area with the exception of Dodge9s (1952) stratigraphic and paleontologic study along the Lehigh Valley Railroad cut (Fig. 2) and Drake9s investigation (1969, 1970) that led to the construction of the first stratigraphic column. Recently, Drake (1969), Rodgers (1971), and Zen (1972) have adopted the view that the Jutland sequence is a klippe of the same type as the Taeonic klippe of eastern New York and New England. The sequence of variegated shales, quartz sandstones, limestones, limestone conglomerate, and quartz pebble conglomerate, herein defined as the Jutland sequence, differs, however, in that it is found on the southeast side of the Reading Prong, whereas most of the transported sequences of this type are found northwest of Precambrian crystalline rocks. This study was undertaken to test the klippe hypothesis. The bulk of the evidence favors the view that the Jutland area rocks are allochthonous, largely inverted, and that they are in part older than and in part the same age as the immediately adjacent carbonate sequence which is right-side-up. The Taconide Zone of the Appalachian Orogen is comprised of lower Paleozoic, predominantly pelitic rocks that slid or were thrust to the northwest over or toward a carbonate bank during the latter part of Middle Ordovician time. This zone extends almost continuously from Newfoundland to southeastern New York. The continuation of the Taconide Zone into New Jersey and beyond is still being debated. Alterman (1971) and MacLachlan (1964) have demonstrated that a pelitic sequence resting atop carbonate rocks in eastern Pennsylvania forms a Taconic-style allochthon (The Hamburg Klippe). Pelitic rocks near Annandale (Pennsylvania) and Ralston (New Jersey) (see Fig. 1) may also be allochthonous and part of the Taconide Zone (Rodgers, 1971; D. B. MacLachlan, 1976, written commun.), but detailed field work is required to support this possibility.