eustaticadj.

1906 H. B. C. Sollas & W. J. Sollas tr. E. Suess Face of Earth II. iii. xiv. 538 We must commence by separating from the various other changes which affect the level of the strand, those which take place at an approximately equal height, whether in a positive or negative direction, over the whole globe; this group we will distinguish as eustatic movements. The formation of the sea basins produces spasmodic eustatic negative movements.

1935 Nature 28 Sept. 492/2 But the more recent the eustatic emergence, the fewer are the dangers of mistaking the traces of the corresponding strand-lines on the rocks of continents and islands.

1946 F. E. Zeuner Dating Past iii. 47 Such movements of the sea-level are called eustatic, and the phenomenon, glacial eustasy.

1934 R. A. Daly Changing World of Ice Age vii. 226 Assume that in the last Inter-glacial stage, when sea level rose on the bank eustatically, a main atoll reef..grew up.

1939 Proc. Prehistoric Soc. 5 264 Sea-level..rose and fell eustatically in response to the melting and growth of ice-sheets.

1935 H. Baulig Changing Sea Level 4 We have to consider..eustatic movements, resulting from changes in the capacity of the oceanic basins, a kind of eustatism which might be called deformational.

1954 W. D. Thornbury Princ. Geomorphol. vi. 142 Diastrophic eustatism is change of sea level resulting from variation in capacity of the ocean basins, whereas glacio-eustatism refers to changes in sea level produced by withdrawal or return of water to the oceans.

1970 R. J. Small Study of Landforms xii. 425 Successive eustatic falls, independent of those attributable to glacial eustatism, occurred either as the ocean basins were deepened and/or the continental land areas raised en masse.