Kenneth R. Walker, 1969. "A Mineralogical, Petrological, and Geochemical Investigation of the Palisades Sill, New Jersey", Igneous and Metamorphic Geology, Leonard H. Larsen, Martin Prinz, Vincent Manson
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Detailed study of the Palisades Sill has revealed new information on its mineralogy, and, in particular, on the relationships between pyroxenes and olivine in the late fractionation stages, beyond the so-called two-pyroxene field in the pyroxene quadrilateral. In addition, the chemical investigation identified the sill as a multiple intrusion containing two main magma phases. The geochemical study on the distribution of elements, and their behavior with fractionation in tholeiitic magma, indicated the importance of fractional crystallization in the differentiation process. The degree of differentiation shown by the sill was largely controlled by the rate at which the intrusion cooled, for this determined the contribution to differentiation by gravity settling in the early stages of crystallization and the extent of fractional crystallization possible throughout cooling. Differentiation was toward iron-, silica-, and alkali-enrichment, and its range and trend are similar to those in other tholeiite provinces elsewhere.