An evaluation of the post-ignition unblocking behavior of solid propellant aft-end ignition systems Final report

Determining postignition interactions between igniter and main motor flow by aft-end heated air simulation of solid propellant exhaus

Paleogeographic evolution of the Southern Pannonian Basin: 40Ar/39Ar age constraints on the Miocene continental series of notthern Croatia

The Pannonian Basin, originating during the Early Miocene, is a large extensional basin incorporated between Alpine, Carpathian and Dinaride fold-thrust belts. Back-arc extensional tectonics triggered deposition of up to 500-m-thick continental fluvio-lacustrine deposits distributed in numerous sub-basins of the Southern Pannonian Basin. Extensive andesitic and dacitic volcanism accompanied the syn-rift deposition and caused a number of pyroclastic intercalations. Here, we analyze two volcanic ash layers located at the base and top of the continental series. The lowermost ash from Mt. Kalnik yielded an 40Ar/39Ar age of 18.07 ± 0.07 Ma. This indicates that the marine-continental transition in the Slovenia-Zagorje Basin, coinciding with the onset of rifting tectonics in the Southern Pannonian Basin, occurs roughly at the Eggenburgian/ Ottnangian boundary of the regional Paratethys time scale. This age proves the synchronicity of initial rifting in the Southern Pannonian Basin with the beginning of sedimentation in the Dinaride Lake System. Beside geodynamic evolution, the two regions also share a biotic evolutionary history: both belong to the same ecoregion, which we designate here as the Illyrian Bioprovince. The youngest volcanic ash level is sampled at the Glina and Karlovac sub-depressions, and both sites yield the same 40Ar/39Ar age of 15.91 ± 0.06 and 16.03 ± 0.06 Ma, respectively. This indicates that lacustrine sedimentation in the Southern Pannonian Basin continued at least until the earliest Badenian. The present results provide not only important bench marks on duration of initial synrift in the Pannonian Basin System, but also deliver substantial backbone data for paleogeographic reconstructions in Central and Southeastern Europe around the Early–Middle Miocene transition

Geodynamics at the Alps-Dinarides junction in Slovenia after geological, seismological and geodetic data

Central Europe Regional Geodynamic Project (CERGOP) in Slovenia includes GPS measurements on 5 sites. Within the first part of the project during years 1994-1997, measurements were performed on one site (Ljubljana), and during the CERGOP-2 extension in years 1999-2005 additional 4 sites were added (Božica, Malija, Snežnik and Mrzlica). However, till now measurements on the three sites only (Ljubljana, Božica and Malija) have been completed. Obtained data show similar sense and amount of horizontal displacements. They exhibit general northward movement of sites at the average velocity of 3 mm/yr. This is in accordance with results obtained from other sites of cirkum-Adriatic region, and it confirms the northward movement of the Adriatic microplate towards the “stable” Eurasian plate. In Slovenia, a northward oriented δ1 tensor have been also obtained from several tens of earthquake fault plane solution. Slight defferences in sense and velocity of displacements among particular sites could be explained by the influence of local structures. In Slovenia, they belong to the Periadriatic dextral shear zone, to the Dinaric dextral shear zone, and to the Transdanubian sinistral shear zone. However, the real dynamics of particular structures, among which some also express co-seismic creep, will be possible to determine only by GPS measurements over a denser network of sites