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Use of the Internet is proliferating rapidly, with mounting speculation as to the practical applications for teaching in higher (and other sectors of) education, yet few published or evaluated case studies are available. This paper explores the use of Internet sources on geography courses. For various academic, logistic and philosophical reasons that are discussed, students were not given full access to the Internet, but were exposed to a variety of current Internet-sourced material downloaded onto a network fileserver, and encouraged to communicate internally and externally using electronic mail. This procedure maintained some of the vitality and stimulation of open access to the Internet, whilst providing some control over potential dangers inherent in this untested teaching medium. Evaluations of the student coursework performance on, and perception of, courses involving the Internet indicate no significant impairment in either during the first staging of the course, but substantial improvemen...

The Tabernas Basin in southeast Spain is a Neogene intermontane basin which filled with sub-aerial and submarine fan conglomerates grading into turbidite sandstones towards the basin centre. The basin history involved the development of Seravallian-Tortonian subaerial fans which coalesced southwards from the basin margin. Increasing water depth in the Tortonian led to a submarine development of these fans. The coarse fan conglomerates are colonized almost solely by barnacles of the species Megabalanus tintinnabulum, known from Miocene-Recent deposits. The barnacles occur in seven preservational-state assemblages, which provide a record of the colonization of stabilized mass-flow conglomerates and of subsequent reworking episodes. M. tintinnabulum is known from intertidal environments today. In situ clusters developed on the fan conglomerates record the transition of the fans from subaerial to submarine environments. Mass-flow deposits rich in barnacle shell debris are representative of basin-wards reworking of intertidal clusters and illustrate relative increase in water depth. A further shallowing episode is identifiable by the recolonization of mass flows by in situ barnacle clusters. This case history is demonstrative of the utility of some barnacles in determining basin history with respect to minor sea level fluctuations.

Dropstones are clasts which pose a hydrodynamic paradox or which have an exotic or extra-basinal lithology with uncertain provenance. Recently, dropstones have been consistently interpreted as the product of ice rafting, and have been used to substantiate the presence of cool climatic phases in the geological record. This review illustrates that not all dropstones are reliable as palaeoclimatic indicators. Dropstones are the product of two distinct entrainment and transport mechanisms: by a rafting agent, or as a projectile. Four main processes of transport and formation are identified: biological rafting, ice rafting, floatation and projectiles. Biological rafting agents include vertebrate gastroliths and other stomach contents, vegetational rafting and anthropomorphic activity. Ice rafting can be the product of ice bergs or seasonal sea, river or lake ice. Floatation of clasts in calm waters has been recorded for stones up to 25 mm in length. Projectiles are most commonly of volcanic origin. Given the range of transport and depositional mechanisms reviewed we argue that great care is required in the interpretation of the origin of dropstones.

A valuable overview of the lithostratigraphical variation of the Purbeck Limestone Group across its Dorset type-area (within the Wessex sub-basin of northern Europe) is gained from new logging of coastal sections in west and central parts of south Dorset, and re-evaluation of previous detailed work further east. An adapted lithostratigraphical classification is presented, which divides the group into the two existing formations (Lulworth and Durlston), five new members, and fifteen or so traditional beds. The members were set up in the more representative west and central parts of the basin; they have been designed to reflect broad sedimentary variations in the group, and thus are useful for inland mapping and will be helpful for palaeogeographical analysis. The beds are the traditional minor divisions of the group conceived in the last century, which have been promoted recently by some authors to member status. The problematic historic ‘Lower’, Middle' and ‘Upper’ divisions are not used, in agreement with many recent researchers. The type-section of the group, at Durlston Bay in the east is placed in a regional context. It is revealed that the lower part of the sequence, the Lulworth Formation, is at its most lithologically variable in the west, whilst its upper part, the Durlston Formation, is more variable in the east. The work may help in discussions on the position of the base of the Cretaceous in relation to the Purbeck Limestone Group.

Sedimentary basins developed in tectonically active areas commonly display dramatic changes in sedimentation rates, styles and spatial organization of alluvial facies. When deformation rates are relatively high these changes are frequently attributed to deflection and/or ponding of the fluvial systems. This paper examines the indirect modifications that less intense, epeirogenic uplift may instigate, during the latter stages of basin inversion, in the context of a fluvial system adjusting to the deformation. Field evidence is taken from the Sorbas Basin of south-east Spain and data are employed from both the current drainage pattern and ancient (Plio-Quaternary) sedimentary sequence. Major provenance and sedimentation changes in the ancient record (in terms of both rates and styles) are attributed to river capture. Intrinsic controls to the system (fan progradation and trenching) and the prevailing (semi-arid) climate provided the overall framework of fan development (general coarsening upwards sequence and change from sheetflood to braided conditions in the lower part of the sequence). This sedimentation trend was then substantially modified (a change to small meandering channels and a change in provenance) by the capture of the fan feeder by an aggressive subsequent stream. This cut off the connection with the former source area and reduced sediment and water input into the system. Initially the sedimentation rates declined and minor incision was stimulated by the increase in the water to sediment ratio as a result of the reduction in easily erodible sand to the system that resulted from the source area change. This minor incision stimulated a rejuvenation of the streams sourcing the fan, temporarily increasing sediment supply and choking the small channels, leading to a return to unconfined flow conditions. The system rapidly exhausted the sediment from the reduced catchment area leading to a fining upwards and abandonment of the system. This was followed by incision of the modern drainage network stimulated by base level changes in the main Sorbas Basin drainage network, to which the study area was tributary.

The Mediterranean is the westernmost part of the global-scale Alpine-Himalayan orogenic belt which stretches from Spain to New Zealand. The landscapes of the region have a long and complex history that includes both horizontal and vertical crustal movements and the creation and destruction of oceans. This began with the break up of the super-continent Pangea around 250 Ma, which generated the Tethys Ocean—the forerunner to the present-day Mediterranean Sea. Collision of the African and European tectonic plates over the last 30 Ma led to the destruction of the Tethys Ocean, although a few remnants of its geology are preserved within the eastern Mediterranean. It is the collision of Africa and Eurasia, and the associated tectonics that have been largely responsible for generating the Mediterranean Sea, its subsequent history, and the landscapes that surround it. This collisional history progressively reduced the connectivity of the Mediterranean Sea with surrounding marine bodies by closing and restricting marine gateways. During the Miocene, for example, the Mediterranean basin became completely isolated from surrounding marine bodies in what is known as the ‘Messinian Salinity Crisis’. This period saw major changes to the regional water balance leading to evaporation and draw-down of the Mediterranean Sea. This had profound impacts on all aspects of the physical geography of the region including the climatology, biogeography, and geomorphology and its legacy can be seen across the region today. The more recent Quaternary geodynamics of the Mediterranean have generated an area which includes a complex mixture of zones of plate subduction of various ages and stages (Figure 1.1b). The modern Mediterranean includes zones of active subduction associated with volcanic activity—such as the Calabrian arc—and older zones of now quiescent subduction such as the Betic-Rif arc. There is a wide range of seismic activity associated with these regions from deep (600 km) to shallow (

A section equivalent to the Pliocene La Portada Formation exposed in the coastal cliff at Hornitos, northern Chile, contains a ca . 7-10 m thick conglomerate bed. The bed occurs within a succession of shallow marine sandstones and has an erosional contact with underlying strata. The largest boulders of basement (5 m) are angular to very angular and are set within a matrix of very poorly sorted fine to very coarse grained shell-rich sandstone. Also present are very well rounded granodiorite pebbles and shallow marine sandstone intraclasts (maximum 10 m). The clast size, erosional contact, associated facies and bed thickness suggests that the conglomerate bed is a shallow marine tsunami deposit. The angular clasts indicate limited transport and no marine reworking prior to deposition. They represent alluvial fan sediment incorporated into the bed during tsunami backflow. Intraclasts of shallow marine sandstone are thought to have been ripped up and included in the bed during the seaward passage of the tsunami across the shoreface.