JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. The University of Chicago Press is collaborating with JSTOR to digitize, preserve and extend access to The Journal of Geology. A B S T R A C TEvidence for three short-lived compressive episodes of late Carixian, late Callovian-early Oxfordian, and TithonianBerriasian ages that lasted !5 m.yr. and occurred during the process of rifting of the Algarve Basin is presented. These tectonic-inversion episodes are described at outcrop and cartographic scales and have been dated with the accuracy provided by the ammonoid scale. An uplift event of late Toarcian-Aalenian age of undetermined tectonic origin is also described. We show that these four tectonic episodes coincide in time with important ecological events, such as the onset of migration and/or the segregation of Boreal and Tethyan ammonite species and the confinement of the Algarve Basin. Stratigraphic and paleoecological data from the Algarve and Lusitanian Basins are compared and discussed together with eustatic and tectonic information. We propose that the tectonic-inversion episodes that caused uplift are the origin of the Mesozoic sedimentary gaps and the intermittent opening and closure of the seaway located offshore the SW corner of Iberia between the Algarve and Lusitanian Basins (i.e., a seaway between the Boreal and Tethyan realms). Three tectonic mechanisms for the origin of these short-lived compressive episodes are presented after comparing the tectonic setting of the Algarve Basin with other geological provinces of the world where similar phenomena also occurred.

Abstract.A major task of the newly established "Southern African Science Service Centre for Climate Change and Adaptive Land Management" (SASSCAL; www.sasscal.org) and its partners is to provide science-based environmental information and knowledge which includes the provision of consistent and reliable climate data for Southern Africa. Hence, SASSCAL, in close cooperation with the national weather authorities of Angola, Botswana, Germany and Zambia as well as partner institutions in Namibia and South Africa, supports the extension of the regional meteorological observation network and the improvement of the climate archives at national level. With the ongoing rehabilitation of existing weather stations and the new installation of fully automated weather stations (AWS), altogether 105 AWS currently provide a set of climate variables at 15, 30 and 60 min intervals respectively. These records are made available through the SASSCAL WeatherNet, an online platform providing near-real time data as well as various statistics and graphics, all in open access. This effort is complemented by the harmonization and improvement of climate data management concepts at the national weather authorities, capacity building activities and an extension of the data bases with historical climate data which are still available from different sources. These activities are performed through cooperation between regional and German institutions and will provide important information for climate service related activities.

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The growth of surface gravity waves is investigated in an open sea region dominated by swell. An extensive database was collected by the Brazilian Oil Company during the South Atlantic Deep Water Program (PROCAP) in Campos Basin, off coast of Rio de Janeiro. This is the most important petrolic basin in Brazil where tens of drilling platforms are located. The data set contains over 5800 directional wave spectra measured by a heave-pitch-roll buoy in conjunction with meteorological data. A spectral approach is applied in a novel method for the partitioning of sea from swell and for the adjustment of the spectral parameters. The wave growth is investigated and the regression laws of the windsea extracted from the swell-contaminated spectra are compared to earlier works in sheltered areas. It is shown that, on the grounds of the equilibrium range theory, the high-frequency spectral level (the alpha parameter) scale with the reciprocal wave age in the same manner as in unimodal swell-free spectra.

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