Eustatic changes

Fairbridge, R.W. (1961) Eustatic changes of sea level. Phys. Chem. Earth 4, 99-185. 

According to Equation 14.1, the eustatic sea-level changes as well as the vertical crustal movements. The eustatic change is regarded constant over the whole area. Hupfer et al. (2003) propose a local eustatic rise of l.Omm/year for the last century within the western Baltic Sea. The vertical crustal movements show remarkable differences over the entire Baltic Sea area (Fig. 14.3), reflecting here the glacioisostatic adjustment (GIA). The center of uplift is in the Bothnian Bay, with a rate of about 9 mm/year. The coast of the southern Baltic Sea shows subsidence reflecting compensation currents in the upper mantle. 

Regional tectonic processes exert a major control on the room available for sediment to accumulate (accommodation space) by causing either subsidence, which permits continued deposition of sediments, or uplift, which halts deposition and potentially leads to erosion of exposed deposits. Accommodation space in marine basins is also affected by global sea-level (eustatic) changes, which result from changes in the volumes of both the ocean basins and the seawater they hold. The former are tectonically related and potentially can have the greatest effect. 

Sea-level fluctuations (i.e., vertical motion of the sea surface relative to the Earth s center) are caused by either globally synchronous (or eustatic) changes in the volume of water in... 

Moore, K.G., and Kent, D.V. 1987. Testing Cenozoic eustatic changes The critical role of stratigraphic resolution. Cushman Foimdation for Foraminiferal Research, Sp>ecial PubUcation, 24, pp. 51-56. 

The presence of a sequence of uplifted, stepped marine terraces usually corresponds to the superimposition of eustatic change in sea level and of a tectonic uplifting trend that may include sequences of paleoseismic events. The presence of marine terraces several hundred meters above sea level indicates tectonic uplift and allows the estimation of the long-term rate of tectonic deformation. 

Harmon RS, Mitterer RM, Kriausakul N, Land LS, Schwarcz HP, Garrett P, Larson GJ, Vacher HL, Rowe M (1983) U-Series and amino-acid racemization geochronology of Bermuda Implications for eustatic sea-level fluctrration over the past 250,000 years. Palaeogeog Palaeoclim Palaeoecol 44 41-70 Harmon RS, Schwarcz HP (1981) Changes of H and 0 errrichment of meteoric water and Pleistocene glaciation. Natrrre 290 125-128... 

Sleep N.H. (1976) Platform subsidence mechanisms and eustatic sea-level change. Tectonophysics 36, 45-56. 

The RSLR consists of two components the eustatic rise caused by an increase in the water volume of the sea (due to changes in the ratio between the input and output components of the water balance of the sea) and the land subsidence. In many river mouths, the effect of the second factor prevails. 

The mechanism of the transfer of the eustatic component of the world ocean level rise into the Black Sea and the Sea of Azov is an intricate and poorly understood process. It is clear that in these seas the eustatic rise differs from that in the ocean as a whole. The main cause is relative isolation of these seas from the ocean. Thus, the volumetric changes in the sea water levels are likely to be more susceptible to changes in the ratio between the components of the water balance of the sea (river runoff, precipitation, and evaporation) than to the eustatic rise in the ocean level. 

In 1923-1985, the Black Sea was characterized by an increase in its water volume, the rate of which attained + 1.5 km3 year 1 [3]. If one converts this value into the sea level change for the same period (with the sea area being 423 x 103 km2), then the rate of the eustatic sea level rise will be 3.5 mm year x. By different assessments, the eustatic (volumetric) increase in the Black Sea level comprises 2.0-4.0 mm year-1 [3,8,24]. 

Although sea level is closely related to continental ice volume, it is also a function of other variables, most notably isostatic effects (see Clark et al. (1978) and review of Peltier (1998) and references therein). Sea-level change can be divided into a eustatic component, which depends... 

Wilde P., Quinby-Hunt M. S., and Erdtmann B.-D. (1996) The whole-rock cerium anomaly a potential indicator of eustatic sea-level changes in shales of the anoxic facies. Sedim.Geol. 101, 43-53. 

Meisler H., Leahy P. P., and Knober L. L. (1985) Effect of Eustatic Sea Level Changes on Saltwater—Freshwater Relations in the Northern Atlantic Coastal Plain. USGS Water Supply Paper, 2255. 

For the reconstiTiction of coastline change in the Baltic relative sea-level curves for the last 8000 year can be used (Rosentau et al., 2007). They are derived from data of ancient nearshore sediments. To illustrate the general pattern of sea-level change in the Baltic area, eight typical curves are shown in Fig. 14.4. Each curve mirrors the effects of both eustatic sea-level... 

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