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This article uses Vatican and papal documents to reflect on the distinctive mission of Catholic colleges and universities in light of their responsibility to prepare students for virtuous citizenship in a religiously and ethnically pluralistic society. It also shows how one Catholic college understands its academic community in light of such a mission.

This article shows how Merrimack College's Catholic heritage and Augustinian tradition provide intellectual and spiritual resources for the college to fulfill its educational responsibility to prepare students for virtuous citizenship in a religiously and culturally pluralistic society. It uses four major Vatican documents and several foundational Augustinian ideas to elaborate principles useful for the guidance of Merrimack's academic community and the direction of its campus culture. The article concludes with Merrimack's "Statement of Augustinian Values for Higher Education" as an expression of its distinctive mission in American higher education.

Drowned terrestrial wetland environments, such as lakes, marshes, and beaches, were thought to be rare in formerly glaciated regions like the Gulf of Maine (United States). In the northwestern Gulf of Maine, postglacial relative sea-level changes include a 'slowstand' between 11.5 ka and 7.5 ka, when the ocean rose doi: 10.1130/G31002.1

Abstract: Differential sea-level change in formerly glaciated areas is predicted owing to variability in extent and timing of glacial coverage. Newfoundland is situated close to the margin of the former [...]

Hydrographic data--obtained concurrently along the 25 km longitudinal axis of the Kennebec River estuary during a 13 h semidiurnal tidal cycle of a spring freshet superimposed on near-perigean spring tides--revealed a strong ebb-current dominance along the length of the estuary. Ebb-current dominance is produced by riverine flow that supplants a substantial part of the flood-tidal prism. In addition, side-scan sonograms showed a suite of large bed forms (1-12 m height) with nearly ubiquitous ebb orientations veneering the estuary bottom. Embayment geometry, salinity, water temperature, discharge, current velocity, and bed-form data all suggest that ebb-velocity asymmetry, set up by seasonal changes in freshwater discharge superimposed on ebb-directed tides, is the most important control on net bed-load sediment transport within this high-latitude, rock-bound estuary. These data augment a model that shows that a freshwater discharge threshold exists for net seaward bed-load sediment transport. The results from this study can be used to refine existing conceptual sedimentologic and morphologic classifications of estuaries. Keywords: currents, discharge, estuary, freshet, sediment transport.

Accumulations of deltaic and littoral sediments on the inner continental shelf of Maine, Gulf of Maine, preserve a record of postglacial sea-level changes and shoreline migrations. The depositional response of coastal environments to a cycle of regression, lowstand, and transgression was examined with seismic-reflection profiles, vibracores, and radiocarbon dates collected from sediments at the mouths of the Kennebec and Penobscot Rivers. Sequence-stratigraphic analysis of these data reveals two distinctly different successions of late Quaternary deposits that represent end members in an evolutionary model for this glaciated coast. Seaward of the Kennebec River, coarse-grained shorelines with foreset beds occur at depths of 21-60 m and outline the lobate margin of the Kennebec River paleodelta, a complex, rock-framed accumulation of glaciomarine and deltaic sediments capped by estuarine and marine deposits. Sand derived from this system today supports large barrier spits and extensive salt marshes. In contrast, the mouth of the Penobscot River is characterized by thick deposits of glaciomarine mud overlain by marine mud of Holocene age, including gas-charged zones that have locally evolved into fields of pockmarks. The distinct lack of sand and gravel seaward of the Penobscot River and its abundance seaward of the Kennebec River probably reflect differences in sediment sources and the physiography of the two watersheds. The contrasting stratigraphic framework of these systems demonstrates the importance of understanding local and regional differences in sediment supply, sea-level change, bedrock structure, and exposure to waves and tides in order to model river-mouth deposition on glaciated coasts. Evolution of shelf deposits was largely controlled by relative sea level, which locally fell from a highstand (+60 to +70 m at 14 ka) contemporary with deglaciation to a lowstand (-55 m at 10.8 ka). The sea-level lowering was accompanied by fluvial incision of older deposits, producing a regressive, basal unconformity. Major rivers deposited abundant sediment over this surface. Sea level then rose at varying rates, extensively reworking formerly emergent parts of the shelf and producing a shoreface ravinement surface in areas exposed to waves. A tidal ravinement surface has developed in sheltered embayments where erosion is due mainly to tidal currents. Incised valleys in both settings preserve transgressive estuarine deposits that contain lagoonal bivalves and salt-marsh foraminifera at depths of 15-30 m. These deposits accumulated ca. 9.2-7.3 ka, locally a period of relatively slow sea-level rise.

A suite of salt-marsh peat samples from four sites along the coast of Maine (Wells, Phippsburg, Gouldsboro, and Machiasport) has been analyzed using high-precision techniques to determine local relative sea-level trends and to evaluate proposed along-coast warping. A spatially variable set of relative sea-level records in Maine would have important implications for geophysical models that predict the response of the lithosphere during deglaciation and postglacial isostatic relaxation. These models are often at odds with observed relative sea-level indicators near the margins of former glaciation, including those from Maine. Assemblages of agglutinated benthic foraminifera occur in vertical zones on the surface of modern salt marshes in Maine and can be used to accurately locate former mean high water levels in cores. Additional tools in this study include accelerator mass spectrometer 14C dating of individual plant fragments and precise leveling of elevations. The amplification of [M.sub.2] tidal range in the Gulf of Maine and the Bay of Fundy during the Holocene is modeled and applied to the mean high water data yielding best-estimate envelopes of mean tide level change for each location. Average long-term (thousands of years) mean tide level rise did not exceed [approximately equal to]2 mm/yr at any time during the late Holocene at Wells, Phippsburg, and Machiasport. Between 4.5 and 3 ka (calibrated [cal]), the apparent rate of rise at Gouidsboro was higher than at any other site studied. This along-coast variation in the rate of mean tide level rise may reflect time of deglaciation, neotectonics, or differential isostatic adjustments. Between 8 and 5 ka (cal), only south-central Maine (Phippsburg) has a good record of relative sea-level change. At this locality, the rate of mean tide level rise was 5.0-8.8 mm/yr for the period 7.8-5.3 ka (cal), which may have resulted from collapse of a glacial forebulge. A slight acceleration of mean tide level rise has occurred during the past millennium in Gouldsboro and Machiasport. If 12 m downwarping in easternmost Maine occurred, as suggested in other publications, it must have happened prior to 5.7 ka (cal).

New radiocarbon-dated cores obtained by Vibracorers in the western Gulf of Maine confirm that a short-lived, relative sea-level lowstand of [approximately] -55 m occurred at 11-10.5 ka. These cores and younger salt-marsh data also reveal that rates of transgression varied throughout the Holocene, probably due to local variations in glacial isostasy. The isostatic component is resolved by subtracting published approximations of eustatic sea level from our well-determined observations of local relative sea level. A large peak in the isostatic curve coincides with the lowstand and is interpreted as a forebulge 20-25 m in amplitude. Forebulge migration is estimated at 7-11 km/100 yr, based on the timing of lowstands across the region.

Circular depressions, or pockmarks, cover the sea floor in many estuarine regions of the western Gulf of Maine. In Belfast Bay, Maine, they are found in densities up to 160/km squared, are up to 350 m in diameter and 35 m in relief, and are among the largest and deepest known. The pockmarks appear to form from the escape of biogenic natural gas and pore water and are far larger than features associated with thermogenic gas elsewhere. These pockmarks are thought to have formed (1) catastrophically during an earthquake, tsunami, or storm, or (2) slowly over thousands of years. Recent observations of bubble releases suggest continuing activity and a potential geologic hazard. The pockmarks involve a poorly documented coastal process of sediment redistribution and methane release, largely unrecognized in the rock record but widespread in middle- to high-latitude embayments.