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Red beds are well-known for recording stable natural remanent magnetization (NRM). However, discriminating primary NRM from secondary remanence in red beds is difficult. The Paleogene Nangqian red beds in eastern Tibetan Plateau variably record an overprint related to nearby magmatism and thus provide a great opportunity to characterize remagnetization in red beds. Through comprehensive rock magnetic, Mössbauer spectroscopic, and petrographic analyses, we find that remagnetization was controlled by temperature. Remagnetized red beds contain abundant authigenic hematite and goethite, with some larger grains unblocking at the Néel temperatures and the remainder (nanoparticles) unblocking at lower temperatures. In contrast, red beds retaining primary NRM are characterized by dominance of detrital hematite and magnetite, presence of fine-grained authigenic hematite, and absence of authigenic goethite and magnetite. High temperature behaviors of NRM/susceptibility are indicative of remagnetization, but the presence of goethite appears to be a more sensitive criterion for diagnosing remagnetization in red beds.

New rock magnetic results (thermal fluctuation tomography, high-resolution first-order reversal curves and low temperature measurements) for samples from the Paleocene���Eocene thermal maximum and carbon isotope excursion in cored sections at Ancora and Wilson Lake on the Atlantic Coastal Plain of New Jersey indicate the presence of predominantly isolated, near-equidimensional single-domain magnetic particles rather than the chain patterns observed in a cultured magnetotactic bacteria sample or magnetofossils in extracts. The various published results can be reconciled with the recognition that chain magnetosomes tend to be preferentially extracted in the magnetic separation process but, as we show, may represent only a small fraction of the overall magnetic assemblage that accounts for the greatly enhanced magnetization of the carbon isotope excursion sediment but whose origin is thus unclear.

Today, whether in the name of accountability, higher standards, or economic competitiveness, we risk putting the formal school curriculum ahead of the child—a problem that Dewey addressed in 1902. Advantaged and influential individuals and groups unconsciously surrender the individuality, aspirations, and humanity of the child to privileged interests and voices, and in so doing, they unwittingly give or take away the professional roles and responsibilities of educators. That is, educators are frequently stripped of the freedom to think for themselves, to make professional judgments, and to teach in ways that they consider are in the best interest of children and youth, because we wish to prescribe precisely when students learn which specific skills and information. High-stakes testing, for instance, dominates the curriculum and, therefore, the teacher and the student in certain situations. But this scenario is not a completely new one, and we can learn much from Dewey's analysis of similar departures from sound educational thinking. Revisiting The Child and the Curriculum, then, may enable us to better understand and resist some unwarranted contemporary policies and practices.

The application of concepts of sequence stratigraphy to seismic and well data has led to a new understanding of the subsurface Devonian reef complex of the Canning Basin. It demonstrates marked reciprocal sedimentation with lowstand terrigenous sediments largely restricted to the basin and transgressive and highstand carbonate sediments on the platform. Preliminary outcrop studies indicate the potential of these concepts to modify significantly the existing lithostratigraphic and biostratigraphic interpretations of this classic exhumed reef complex, including the stratigraphic context of the Frasnian-Famennian boundary in the Canning Basin.