Although numerous studies have been performed on fluvial system change over the last glacial-interglacial transition, the response of river systems to allogenic (climate) and autogenic forcing mechanisms and timing of this response are still not completely understood (e.g. Starkel, 1983;Vandenberghe et al., 1995;Rose, 1995;Blum & Törnqvist, 2000;Gibbard & Lewin, 2002;Vandenberghe, 2008;Erkens, 2009). The valleys of the Rhine and the Maas in the Lower Rhine Embayment have a long research history on this topic (Pons,1957;Van de Meene, 1977;Verbraeck, 1984;Klostermann, 1992;Schirmer, 1995;Berendsen & Stouthamer, 2001;Cohen et al., 2002;Busschers et al., 2007;Erkens et al., 2011). In this area, a well-preserved terraced morphology exists, with OSL-datable fluvial sequences with aeolian cover and with palaeochannel fills that allow vegetation AbstractIn the Weichselian, the Lower Rhine in the Dutch-German border region has used three courses, dissecting ice-marginal topography inherited from the Saalian. In the Late Weichselian, the three courses functioned simultaneously, with the central one gaining importance and the outer ones abandoning. This study aims to reconstruct the fluvial development and forcings that culminated in abandonment of the northern branch 'Oude IJssel-Rhine', at the time of the Lateglacial to Holocene transition. The fluvial architecture is studied using a cored transect over the full width of the valley, detailed cross-sections over palaeochannels and geomorphological analysis using digital elevation and borehole data. Biostratigraphy, radiocarbon dating and OSL dating provide a timeframe to reconstruct the temporal fluvial development. In its phase of abandonment, the fluvial evolution of the Oude IJssel-Rhine course is controlled by the ameliorating climate and related vegetation and discharge changes, besides by intrinsic (autogenic) fluvial behaviour such as the competition for discharge with the winning central branch and the vicinity of the Lippe tributary confluence. The rapid climate warming at the start of the Late Glacial resulted in flow contraction as the initial response. Other fluvial geomorphic adjustments followed, with some delay. An aggrading braided or transitional system persisted until the start of the Allerød, when channel patterns finally changed to meandering. Floodplain incision occurred at the Allerød -Younger Dryas transition and a multi-channel system developed fed by Rhine discharge. At the start of the Holocene, this system transformed into a small-scale, local meandering system, which was abandoned shortly after the start of the Holocene.The final abandonment of the Oude IJssel-Rhine and Niers-Rhine courses can be attributed to deep incision of the Central Rhine course in the earliest Holocene and is considered to be controlled by flow contraction induced by climate and related vegetation and discharge changes.

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This paper presents a method to automatically extract analytical entities like planes, spheres and cylinders from a file containing a cloud of points. The method facilitates the manipulation and reduction of large data sets and the evaluation of it. It can be used as a design tool, a quality control tool, data-processing tool or a data reduction tool. From a database of points, the user can automatically extract a subset of points belonging to an analytical entity of interest, within a predefined but adjustable level of confidence. If necessary, the dimensional parameters of the entity can also be calculated. The method is based on the subtle statistical properties of the least-squares technique that makes it compliant with the strict regulations in the coordinate measuring arena. Its robustness guarantees. the applicability to less accurate environments than precision engineering. OPSOMMING Hierdie artikel bespreek 'n metode met behulp waarvan analitiese voorwerpe soos vlakke, sfere en silinders outomaties vanuit 'n wolk van datapunte, onttrek kan word. Die metode is geskik vir die hantering, manipulasie, reduksie en evaluasie van groot data-stelle. Dit kan gebruik word as 'n gereedskapstuk vir ontwerp, gehaltebeheer, dataverwerking en data-reduksie. Gegewe 'n databasis van punte, kan die gebruiker die subset van punte wat tot enige analitiese voorwerp van belang behoort, outomaties binne 'n voorafgespesifiseerde, maar verstelbare, vlak van vertroue onttrek. Hierbenewens en indien nodig, kan die dimensionele parameters en afmetings van die betrokke entiteit ook bereken word. Die algoritme maak van die kleinste-kwadrate metode gebruik, sodat elke passings-parameter statisties kwantifiseerbaar en verantwoordbaar is. In hierdie opsig voldoen dit aan die streng regulasies wat die koordinaat-meet arena kenmerk. Die robuustheid van die metode, maak dit ook geskik vir toepassing in minder akkurate omgewings as presisie-ingenieurswese,

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