Introduction

Abstract

Sea level change is the product of many interrelated processes and an integrated measure of environmental phenomena, in terms of both causes and consequences. Changes occur on all space and time scales, from local (relative) to global (eustatic), and from a few second to geologic ages. Relative sea-level change is an important process influencing not only the relative position of the shoreline, but also the characteristics of coastal stratigraphic systems (Ta et al. 2001). It is noticeable that the stratigraphy of coastal lowlands is similar worldwide, being characterized by alternating strata composed of marine and terrestrial sediments (Tooley 1992). The strata occurring in a sedimentary succession are representative of different depositional systems that prevailed in the basin during its life term. In a sedimentary succession the products of the depositional systems are stacked vertically. The paleogeography of an ancient sedimentary basin at a particular time can be reconstructed from a sedimentary succession by knowing the set of depositional systems that existed in the space of the basin contemporaneously. As stated in Walter’s law: from a package of sediments representing a continuum of sedimentation, the ancient array of depositional systems (i.e., the paleogeography) can be reconstructed by spreading out each depositional system (occurring vertically in the package) like a deck of cards. A clear understanding of the sedimentary successions reveal a precise sea-level change (transgression and regression) during the past, especially during the Holocene, which follows “Walther’s Law of facies” (Walther 1924). According to the law, sedimentary environments that started out side-by-side will end up overlapping one another over time due to transgressions and regressions and the result is a vertical succession of beds (Levin 2006). It also states that the vertical succession of facies mirrors the original lateral distribution of sedimentary environments.