I define an evaporite as a salt rock that was originally precipitated from a saturated surface or nearsurface brine by hydrologies driven by solar evaporation (Figure 1.1). This simple definition encompasses a wide range of chemically precipitated salts and includes alkali earth carbonates (Table 1.1). Some workers restrict the term evaporite to those salts formed directly via solar evaporation of hypersaline waters at the earth's surface.

In theoretischen Modellrechnungen von partikelbeladenen Scherschichten (Martin und Meiburg [ 19941 sowie Rqju und Meiburg [ 19941) wurde eine Akkumulation von Teilchen an der Peripherie von Wirbelstrukturen und eine damit einhergehende Ausdünnung der Partikelkonzentration in den Wirbelzentren gefunden. Dieses Entmischungsphänomen ist der zentrale IJntersuchungsgegenstand der vorliegenden Arbeit. Damit diese Entrnischu~lgsphänomele experimentell untersucht werden konnte, mußte vorgängig eine entsprechende Strömung erzeugt werden.

The processes occurring in the upper several meters of marine sediments1 have a profound effect on the local and global cycling of many elements. For example, the balance between carbon preservation and remineralization represents the key link between carbon cycling in active surface reservoirs in the oceans, in the atmosphere, and on land, and carbon that cycles on much longer, geological time scales—in sedimentary rock, and in coal and petroleum deposits (Berner, 1989; Hedges, 1992).

The processes occurring in the upper several meters of marine sediments1 have a profound effect on the local and global cycling of many elements. For example, the balance between carbon preservation and remineralization represents the key link between carbon cycling in active surface reservoirs in the oceans, in the atmosphere, and on land, and carbon that cycles on much longer, geological time scales—in sedimentary rock, and in coal and petroleum deposits (Berner, 1989; Hedges, 1992).

The examination into the sediments of the Western Guiana shelf, the results. of which are recorded in the present report forms part of the study of the continental shelf deposits off the Orinoco delta. The initiative to this investigation was taken by Prof. Dr Ph. H. KUENEN, Director of the Institute of Marine Geology of Groningen University (Holland); the ‘“‘Bataafsche Petroleum Maatschappij N.V.” of The Hague, by their support, have rendered the necessary expeditions possible. The area of investigation, lying off the Orinoco delta in the N.E. of South America, extends from the Venezuelan Testigos Islands in the N.W. to the shelf area off the Essequibo river mouth in British Guiana in the S.E., from nearshore up to the region of the shelf edge (Fig. 1). <...>

Caves occupy incongruous positions in both our culture and our science. The oldest records of modem human culture are the vivid cave paintings from southern France and northern Spain, which are in some cases more than 30,000 years old (Chauvet, et al, 1996). Yet, to call someone a "caveman" is to declare them primitive and ignorant. Caves, being cryptic and mysterious, occupied important roles in many cultures. For example, Greece, a country with abundant karst, had the oracle at Delphi and Hades the god of death working from caves. People are both drawn to and mortified by caves.

The modern geological sciences are characterized by extraordinarily rapid progress, as well as by the development and application of numerous new and refined methods, most of them handling an enormous amount of data available from all the continents and oceans. Given this state of affairs, it seams inevitable that many students and professionals tend to become experts in relatively narrow fields and thereby are in danger of losing a broad view of current knowledge.

Worldwide the majority of water bodies (rivers, reservoirs and lakes) are no longer in a natural morphodynamic status due to anthropogenic interventions in the catchment area as well as in the river itself. Alterations in the catchment, e.g. uprooting, may lead to high sediment intrusions in river systems even during relatively short precipitation events. The effect of high suspended load concentration and the intrusion of fine sediments (clogging) result in a reduction of habitat quality for many aquatic species. Furthermore, the low water quality can negatively affect both macroinvertebrates as well as microbial organisms on the sediment bed due to increased turbidity as well as sediment smothering that alter the light climate and oxygen penetration, respectively.

The current book continues the work of Winterwerp and Van Kesteren (2004) and Mehta (2013). Our main objective is to provide guidelines for good modeling practice to quantify the transport and fate of fine sediment in open water, with emphasis on the marine environment. We emphasize that a (numerical) model should never be an objective by itself. It is always a tool to help answering managerial or engineering questions, or to enhance our understanding of nature. Yet, in this book we do not elaborate on how to use a model as a tool, as this is too unique an issue.

Многие месторождения центральной части Западной Сибири находятся на поздней стадии разработки. В настоящее время проблемой является выяснение причин неравномерности выработки запасов на нефтяных месторождениях. Нет четкого понимания причин образования зон с повышенными остаточными запасами нефти, а также, почему разработка одного объекта идёт по-разному в разных его частях.