Description: The present study was undertaken to investigate the physical and chemical variability in the eastern Gotland Basin. This can serve as an example for the variability in the inner part of an adjacent sea with small tidal influence. Two anchor stations of about four days duration were made, with R.V. "Alkor" in September 1967 and with F.R.V. "Anton Dohrn" in May 1968. On the basis of variations in the physical parameters, and also from continuous recordings of salinity and temperature, c.f., of oxygen and temperature, the presence of internal waves is demonstrated. The variability in the chemical data not only indicate internal waves but also proves the patchlike structure of the water masses with regard to biochemical parameters. The two anchor stations were made during periods of partial and of total stagnation in the deeper parts of the Gotland Basin. Ziel dieser Arbeit ist eine Beschreibung der physikalisch chemischen Veränderlichkeit im östlichen Gotland-Becken, und zwar als Beispiel für die Veränderlichkeit im inneren Teil eines gezeitenarmen Nebenmeeres. Zwei viertägige Ankerstationen wurden durchgeführt, im September 1967 und Mai 1968, mit "Alkor" und "Anton Dohr". Auf Grund der Variationen in den physikalischen Parametern und auch von den kontinuierlichen Registrierungen von Salzgehalt und Temperatur, bzw. von Sauerstoff und Temperatur, werden interne Wellen nachgewiesen. Von der Veränderlichkeit der chemischen Parameter werden neben internen Wellen auch wolkenartige Strukturen der Wassermassen im Bezug auf biochemische Eigenschaften demonstriert. Beide Dauerstationen fielen in einer Periode von teilweiser und von voller Stagnation im Gotland-Becken.

Description: An Hand von erzielten Resultaten mit dem Membran-Salzfühler wird die Genauigkeit dieser Methode zur Registrierung der Salzschichtung diskutiert. Die Reproduzierbarkeit der Meßergebnisse wird besprochen. Einige Messungen in der Ostsee werden als Beispiele angeführt. With the aid of some results the accuracy of the membrane salinity sensor is discussed. The reproducibility of the measurements is determined. Some recordings in the Baltic Sea demonstrate the usefulness of the method.

Description: The sensitivity of the membrane salinometer to the various ionic species that constitute the dissolved salts in sea water is investigated. Mixtures of various salts with sodium chloride are investigated with regards to changes in the electromotive force upon dilution with water, and also with regards to changes in the composition of the mixed electrolyte. The results are expressed in terms of changes in the activity of sodium chloride. Also sea water is investigated upon a similar basis. Die Empfindlichkeit des Membransalinometers für die verschiedenen Ionensorten, welche im Meersalz vorhanden sind, wird untersucht. Mischlösungen von verschiedenen Salzen mit Natriumchlorid werden im Zusammenhang mit Veränderungen in der elektromotorischcn Kraft sowohl bei Verdünnung mit Wasser, als auch bei Änderung der Zusammensetzung, untersucht. Mit der Aktivität von Natriumchlorid als Referenz werden die Resultate von modifizierten Nernst-Gleichungen beschrieben.

Description: Interstitial waters were collected at only two sites during Leg 82, Sites 558 and 563. Only very small changes in dissolved calcium and magnesium occur, presumably resulting from reactions in the underlying basement basalts. Dissolved strontium profiles indicate maxima, which can be understood in terms of carbonate recrystallization processes. Data on Sr/Ca in carbonates cannot be used to estimate the extent of recrystallization that has occurred in these sediments.

Description: Changes in the dissolved oxygen content, the alkalinity, and the pH in sea water near the ocean floor are interpreted in terms of chemical and biochemical processes at the sediment water interface. A simple model provides a plausible explanation of the observed phenomena. Special emphasis is given to the importance of borate corrections in the calculation of the solution effects of calcium carbonate.

Description: Offset of prograde hydrothermal alterations by retrograde reactions is evident in sediments from a piston core (PC6, 8 m long) from the Guaymas Basin, Gulf of California. Geochemical and mineralogical analyses of sediments and pore fluids show superimposed geochemical signals that indicate currently active reactions are modifying previously formed secondary solids. Hydrothermal barite was formed in a previously active flow channel between 150 and 250 cm depth. Hydrothermal gypsum is presently dissolving at depths 〉780 cm, below which hydrothermal fluid flow is channeled by a secondary dolomite layer. Thermal stress of organic matter generates hydrothermal gas and petroleum having wide ranges of compositions and maturities. A significant amount of hydrothermally generated oil has been transported laterally through a porous debris flow (approx. 240 cm subbottom), overwhelming the indigenous bituminous matter. Water soluble petroleum constituents have disseminated throughout the cored sediments. From 400 to 700 cm depth the immature organic matter continues to experience thermally-enhanced diagenesis, and an even higher thermal stress has occurred at the bottom of the core. Enhanced bacterial degradation of organic matter has led to depletion of pore water sulfate and enrichment of ammonium (NH4+) in both pore fluid and sediment, resulting in formation of NH4+ bearing secondary clay minerals at depths below 780 cm.