Читать книгу Continental Rifted Margins 1 - Gwenn Peron-Pinvidic - Страница 39

In geology, the term “sag basin” is used to describe deep, large-scale basins with an overall circular/elliptical shape (Kingston et al. 1983; Middleton 1989). Interior cratonic basins are often referred to as sag-type basins, displaying accumulations of sediments in an overall oval, long-lasting depression. The formation of sag basins is hypothesized to be driven by long-lasting thermal subsidence (Sleep 1971) and not involve major faulting. In the recent literature, the term “sag basin” has been widely used to describe basins encountered in distal rifted margins, usually referring to large-scale (>100 km wide) basins displaying conformable sedimentary sequences that are draped over underlying faulted topography (see the expanded description in Chapter 2).