Radar investigations of Apollinaris Mons on Mars: Exploring the origin of the fan deposits

Apollinaris Mons is an isolated volcano on Mars straddling the boundary between the southern highlands and the northern plains. One of its most distinctive features is its massive fan-shaped deposit that extends from a breach on its summit to distances of more than 150 km and drapes its entire southern flank. The composition and formation mechanism of these deposits remains controversial. We investigate the radar properties of the fan deposits (FD) of Apollinaris Mons using low-frequency sounding radar data in combination with high-resolution images and crater-size frequency analysis to constrain their inner shape and bulk composition. Our analysis indicates that the FD attains an irregular thickness and is gradually thinner towards their lateral margins. The crater-size frequency analysis shows that they may have undergone repeated resurfacing, which is suggestive of long-term evolution. Our analysis of Shallow Radar (SHARAD) radargrams traversing different sections of the FD reveals multiple and different subsurface interfaces among the radargrams crossing the thinnest part, which suggests a layered and complex inner shape. Our estimates for the bulk real part of the dielectric constant of the FD ranges from 3 to 5, which is consistent with an icy-silicate mixture or pyroclastic composition. Therefore, we conclude that lahars or pyroclastic flows are the most likely mechanism that created the FD, yet we cannot rule out additional contributions from lava flows. A combination of multiple processes is also possible since the deposits appear to have been modified by fluvial processes at a later stage of their formation.

Di hofenung : [fanṭazi in ayn aḳṭ]

M. Franḳenṭal

The Impact of Mobile Technology on the Viewing Experience of the Avid Sports Fan

Viewing sports on television is a very different experience than viewing a game in-person. Sports commentators on television are seemingly able to pull up random statistics as soon as something unexpected happens during a game. Because these statistics are discussed on television, any sports fan who wants to watch a game in-person misses out on the opportunity to hear them during the game. This study identifies what statistics, both common and uncommon, are considered important or interesting by avid sports fans who watch a particular sport at least two times per week. In addition, it considers the rise of mobile technology and the effects that this change of trend will have on business opportunities and experiences. The purpose of the project is to find a way to mimic the television viewing experience for fans who are watching in-person through the use of mobile technology, and in particular through the use of iPhone applications.

Physical properties of 4 cores from the Bengal Fan

New stratigraphic and high-resolution seismic data from the Bengal Fan indicate that the world's largest fan shows active growth during the most recent sea-level rise and the recent highstand. This unique phenomenon contradicts common sequence-stratigraphic models, and the sediment preserved provides new insight into the sedimentological response of a fan system to sea-level rise, climatic terminations, and monsoon intensity during the past climatic cycle. We present a detailed dated sequence of turbidite sedimentation based on a core transect perpendicular to the active channel-levee system in the upper mid-fan area. Between the two major terminations 1a (12 800 14C yr B.P.) and 1b (9700 14C yr B.P.), and especially at the end of the Younger Dryas, a 13-km-wide channel built up levees 50 m high. With decreasing sediment supply, continued sea-level rise, and increasing monsoon intensity during the early Holocene, turbidity currents were confined to the channel and gradually filled it. The canyon "Swatch of No Ground," a shelf depocenter that serves as the source for frequent turbidity currents, and the channel-levee system provide the unique opportunity for studying an active highstand system. Many fans showed this behavior only during lowered sea-level.

Physical properties of sediment cores of the Bengal Fan

We examined geophysical data from a Multi-Sensor Core Logger (MSCL), a logging device providing continuous measurements of gamma-ray attenuation, p-wave travel time, and magnetic susceptibility on marine sediment cores. In the first part we focused on the gamma-ray system and compared two different calibration methods. From the gamma-ray attenuation, we calculated densities and porosities by incorporating mass weighted attenuation coefficients. The application of an iteration method reduces the error of the density and porosity estimates compared to GRAPE data. In addition, we derived equations to calculate water content and dry bulk density from gamma-ray attenuation measurements. Comparison with physical properties determined on discrete samples revealed a very good correlation of both data sets (r = 0.99). This correlation is valid for sediments from substantially different geological settings (e.g., turbidites, hemipelagic muds, and opal-rich sediments). In the second part we applied our data to marine geological questions. For sediments from the Antarctic Polar Frontal Zone, there is indication that the content of biogenic opal can be assessed using a correlation of density and p-wave velocity. For sediments from the Bengal Fan, the relationship between the MSCL acoustic impedance (the product of density and p-wave velocity) and the grain-size distribution in discrete samples can be used to predict clay and sand/silt ratios for sediment cores from the shelf and upper continental slope.

Physical properties of 39 sediment cores from the Bengal Fan and northeast Indian Ocean

We obtained sediment physical properties and geochemical data from 47 piston and gravity cores located in the Bay of Bengal, to study the complex history of the Late Pleistocene run-off from the Ganges and Brahmaputra rivers and its imprint on the Bengal Fan. Grain-size parameters were predicted from core logs of density and velocity to infer sediment transport energy and to distinguish different environments along the 3000-km-long transport path from the delta platform to the lower fan. On the shelf, 27 cores indicate rapidly prograding delta foresets today that contain primarily mud, whereas outer shelf sediment has 25% higher silt contents, indicative of stronger and more stable transport regime, which prevent deposition and expose a Late Pleistocene relic surface. Deposition is currently directed towards the shelf canyon 'Swatch of No Ground', where turbidites are released to the only channel-levee system that is active on the fan during the Holocene. Active growth of the channel-levee system occurred throughout sea-level rise and highstand with a distinct growth phase at the end of the Younger Dryas. Coarse-grained material bypasses the upper fan and upper parts of the middle fan, where particle flow is enhanced as a result of flow-restriction in well-defined channels. Sandier material is deposited mainly as sheet-flow deposits on turbidite-dominated plains at the lower fan. The currently most active part of the fan with 10-40 cm thick turbidites is documented for the central channel including inner levees (e.g., site 40). Site 47 from the lower fan far to the east of the active channel-levee system indicates the end of turbidite sedimentation at 300 ka for that location. That time corresponds to the sea-level lowering during late isotopic stage 9 when sediment supply to the fan increased and led to channel avulsion farther upstream, probably indicating a close relation of climate variability and fan activity. Pelagic deep-sea sites 22 and 28 contain a 630-kyear record of climate response to orbital forcing with dominant 21- and 41-kyear cycles for carbonate and magnetic susceptibility, respectively, pointing to teleconnections of low-latitude monsoonal forcing on the precession band to high-latitude obliquity forcing. Upper slope sites 115, 124, and 126 contain a record of the response to high-frequency climate change in the Dansgaard-Oeschger bands during the last glacial cycle with shared frequencies between 0.75 and 2.5 kyear. Correlation of highs in Bengal Fan physical properties to lows in the d18O record of the GISP2 ice-core suggests that times of greater sediment transport energy in the Bay of Bengal are associated with cooler air temperatures over Greenland. Teleconnections were probably established through moisture and other greenhouse-gas forcing that could have been initiated by instabilities in the methane hydrate reservoir in the oceans.

Del Mp3 al Fan Shot Multicam, génesis de nuevos lenguajes multimedia

Esta ponencia analiza la usabilidad, mutación y dominio de una interfaz multimedia determinada con un enfoque tecnológico sociocultural, económico y productivo; partiendo de la utilización, masificación, mercantilización y difusión de contenidos electrónicos que culminan en procesos de domesticación de los mismos para su posterior remediación. La construcción de lenguajes en tanto actividades concretas dentro de interfases de uso común, están presentes en el marco de practicas culturales que sectores de la población mantienen al seno de sus vidas cotidianas. Así, el usuario apropia, consume y reinterpreta lenguajes impuestos mediante la creación de otros nuevos, que destaquen/condicionen la utilización de dispositivos e interfases dadas. Reflexionando entonces, sobre el affordance entre el usuario y la máquina en tanto intercambio comunicativo; esta ponencia toma como ejemplo el registro 'amateur' de la gira Lights In The Sky de la agrupación Nine Inch Nails en 2007 entendiendo que, a partir de la estandarización de formatos de transmisión de datos, particularmente de tecnologías aplicadas a la difusión e intercambio de contenidos musicales, nos ubicamos al frente de un nuevo punto de partida, condicionado y potenciado por un ciclo de experiencias y desarrollo lingüístico que ha corrido de la mano del ciclo tecnológico de la ultima década

Del Mp3 al Fan Shot Multicam, génesis de nuevos lenguajes multimedia

Esta ponencia analiza la usabilidad, mutación y dominio de una interfaz multimedia determinada con un enfoque tecnológico sociocultural, económico y productivo; partiendo de la utilización, masificación, mercantilización y difusión de contenidos electrónicos que culminan en procesos de domesticación de los mismos para su posterior remediación. La construcción de lenguajes en tanto actividades concretas dentro de interfases de uso común, están presentes en el marco de practicas culturales que sectores de la población mantienen al seno de sus vidas cotidianas. Así, el usuario apropia, consume y reinterpreta lenguajes impuestos mediante la creación de otros nuevos, que destaquen/condicionen la utilización de dispositivos e interfases dadas. Reflexionando entonces, sobre el affordance entre el usuario y la máquina en tanto intercambio comunicativo; esta ponencia toma como ejemplo el registro 'amateur' de la gira Lights In The Sky de la agrupación Nine Inch Nails en 2007 entendiendo que, a partir de la estandarización de formatos de transmisión de datos, particularmente de tecnologías aplicadas a la difusión e intercambio de contenidos musicales, nos ubicamos al frente de un nuevo punto de partida, condicionado y potenciado por un ciclo de experiencias y desarrollo lingüístico que ha corrido de la mano del ciclo tecnológico de la ultima década

Del Mp3 al Fan Shot Multicam, génesis de nuevos lenguajes multimedia

Esta ponencia analiza la usabilidad, mutación y dominio de una interfaz multimedia determinada con un enfoque tecnológico sociocultural, económico y productivo; partiendo de la utilización, masificación, mercantilización y difusión de contenidos electrónicos que culminan en procesos de domesticación de los mismos para su posterior remediación. La construcción de lenguajes en tanto actividades concretas dentro de interfases de uso común, están presentes en el marco de practicas culturales que sectores de la población mantienen al seno de sus vidas cotidianas. Así, el usuario apropia, consume y reinterpreta lenguajes impuestos mediante la creación de otros nuevos, que destaquen/condicionen la utilización de dispositivos e interfases dadas. Reflexionando entonces, sobre el affordance entre el usuario y la máquina en tanto intercambio comunicativo; esta ponencia toma como ejemplo el registro 'amateur' de la gira Lights In The Sky de la agrupación Nine Inch Nails en 2007 entendiendo que, a partir de la estandarización de formatos de transmisión de datos, particularmente de tecnologías aplicadas a la difusión e intercambio de contenidos musicales, nos ubicamos al frente de un nuevo punto de partida, condicionado y potenciado por un ciclo de experiencias y desarrollo lingüístico que ha corrido de la mano del ciclo tecnológico de la ultima década

Rare earth elements of modern seeps from the Gulf of Mexico, the Black Sea, and the Congo Fan

At marine seeps, methane is microbially oxidized resulting in the precipitation of carbonates close to the seafloor. Methane oxidation leads to sulfate depletion in sediment pore water, which induces a change in redox conditions. Rare earth element (REE) patterns of authigenic carbonate phases collected from modern seeps of the Gulf of Mexico, the Black Sea, and the Congo Fan were analyzed. Different carbonate minerals including aragonite and calcite with different crystal habits have been selected for analysis. Total REE content (SumREE) of seep carbonates varies widely, from 0.1 ppm to 42.5 ppm, but a common trend is that the SumREE in microcrystalline phases is higher than that of the associated later phases including micospar, sparite and blocky cement, suggesting that SumREE may be a function of diagenesis. The shale-normalized REE patterns of the seep carbonates often show different Ce anomalies even in samples from a specific site, suggesting that the formation conditions of seep carbonates are variable and complex. Overall, our results show that apart from anoxic, oxic conditions are at least temporarily common in seep environments.