Flood routing of the Maja outflow across Xanthe Terra

The object is to trace a single flood crest through the Maja outflow system and to evaluate the effects of topography on ponding and multiple channel routing. Maja Valles provides a good model because it has a single source and a well defined channel system. The 1500 km long Maja Valles originates in Juventae Chasma. The outflow system stretches 1100 km northward along the Lunae Planum/Xanthe Terra boundary, then eastward across the Xanthe Terra highlands. It descends to Chryse Planitia where it extends northeastward toward the middle of the basin. It is concluded that flood routing through multiple channels and retardation in local impoundments are responsible for breakup of the initial flood crest and the formation of multiple flood crests. Recombined flow near the mouths of these canyons results in an extended flow regime and multiple flood surges. As a result of ponding along the flood course, depositional sites are localized and renewed erosion downstream (from ponded sites) results in sediment source areas not greatly removed from depositional sites

Photogeologic mapping of Meridiani Sinus region from Mariner 6 and 7 imagery

Photogeologic mapping of Mariner photographs characterizes major stratigraphic units of the Martian equatorial region. The low resolution photomosaic ship across Meridiani Sinus Deucalionus Regio is divided into regional map units based on albedo and crater density. High resolution frames reveal map units defined by varying surface texture, crater densities, and degree of crater sharpness. Mariner photographs provide clear evidence of eolian action and channelization by fluid flow

Geologic structure of shallow maria

Isopach maps and structural contour maps of the eastern mare basins (30 deg N to 30 deg S; 0 deg to 100 deg E), constructed from measurements of partially buried craters, are presented and discussed. The data, which are sufficiently scattered to yield gross thickness variations, are restricted to shallow maria with less than 1500-2000 m of mare basalts. The average thickness of basalt in the irregular maria is between 200 and 400 m. Correlations between surface topography, basalt thickness, and basin floor structure are apparent in most of the basins that were studied. The mare surface is commonly depressed in regions of thick mare basalts; mare ridges are typically located in regions of pronounced thickness changes; and arcuate mare rilles are confined to thin mare basalts. Most surface structures are attributed to shallow stresses developed within the mare basalts during consolidation and volume reduction

The K-Step Spatial Sign Covariance Matrix

The Sign Covariance Matrix is an orthogonal equivariant estimator of mul- tivariate scale. It is often used as an easy-to-compute and highly robust estimator. In this paper we propose a k-step version of the Sign Covariance Matrix, which improves its e±ciency while keeping the maximal breakdown point. If k tends to infinity, Tyler's M-estimator is obtained. It turns out that even for very low values of k, one gets almost the same e±ciency as Tyler's M-estimator.

On the Optimality of Multivariate S-Estimators

In this paper we maximize the efficiency of a multivariate S-estimator under a constraint on the breakdown point. In the linear regression model, it is known that the highest possible efficiency of a maximum breakdown S-estimator is bounded above by 33% for Gaussian errors. We prove the surprising result that in dimensions larger than one, the efficiency of a maxi- mum breakdown S-estimator of location and scatter can get arbitrarily close to 100%, by an appropriate selection of the loss function.Breakdown point;Multivariate Location and Scatter;Robustness;S-estimator

Stratigraphy of the south polar region of Ganymede

A preliminary assessment is made of the stratigraphy and geology in the south polar region of the Jovian satellite, Ganymede. Geologic mapping is based on inspection of Voyager images and compilation on an airbrush base map at a scale of 1:5M. Illumination and resolution vary greatly in the region. Approximately half of the quadripole is beyond the terminator. Low angle illumination over a large part of the area precludes distinction of some units by albedo characteristics. Several types of grooved terrain and groove related terrain occur in the southern polar region. Grooves typically occur in straight to curvilinear sets or lanes. Bright lanes and grooved lanes intersect at high angles outlining polygons of dark cratered terrain. Groove sets exhibit a range of ages as shown by superposition or truncation and by crater superposition ages

Thickness of western mare basalts

An isopach map of the basalt thickness in the western mare basins is constructed from measurements of the exposed external rim height of partially buried craters. The data, although numerically sparse, is sufficiently distributed to yield gross thickness variations. The average basalt thickness in Oceanus Procellarum and adjacent regions is 400 m with local lenses in excess of 1500 m in the circular maria. The total volume of basalt in the western maria is estimated to be in the range of 1.5 x 10 to the 6th power cu km. The chief distinction between the eastern and western maria appears to be one of basalt volumes erupted to the surface. Maximum volumes of basalt are deposited west of the central highlands and flood subjacent terrain to a greater extent than on the east. The surface structures of the western maria reflect the probability of a greater degree of isostatic response to a larger surface loading by the greater accumulation of mare basalt

A highland sample strategy for Pathfinder

Potential landing sites are confined to latitudes between 0 deg and 30 deg N and surfaces below 0 km elevation. The landing ellipse is 100 x 200 km oriented N 74 deg E. The constraints essentially eliminate the slopes of Elysium Mons, Olympus Mons, Tharsis Ridge, Lunae Plaunum, all the southern highlands, and almost all the Noachian material of Arabia Terra. Those areas that remain as potential landing sites are chiefly lowland plains of Amazonis Chryse, Isidis, and Elysium Planitia. Any attempt to sample highland material further constrains the possible landing sites by eliminating areas of Hesperian or Amazonian lavas and sediments. One possible sampling strategy is to sample materials within those few 'highland' terrains that extend to low elevations. A second strategy is to sample materials at the mouth of an outflow channel that drains from the highlands. Potential landing sites include outflow channel material at the edge of Chryse Planitia and highland materials bordering southern Amazonis Planitia

Engendering Accountability: Gender Crimes Under International Criminal Law

Gender crimes, such as rape, sexual assault, sexual slavery, and forced prostitution, have always been perpetrated during war, yet the laws of war have been slow to acknowledge these crimes and to bring their perpetrators to justice. This article examines the response of the International Criminal Tribunals for the Former Yugoslavia and Rwanda to this lacuna in international law, and analyzes the mainly positive developments they have made in this area in relation to the definition of rape and to the prosecution of gender crimes as crimes against humanity, war crimes, grave breaches of the Geneva Conventions, and genocide. It also traces the procedural safeguards instituted to facilitate the prosecution of gender crimes. The authors consider the way in which these advances have been taken forward in the Statute of the International Criminal Court, and the usefulness of other responses, such as the truth commissions in Bosnia and Yugoslavia, and the gacaca courts in Rwanda