Relative dating stratigraphy
Loosely stated, the principle says that the various natural phenomena observed today must also have existed in the past (see below The emergence of modern geologic thought: Lyell’s promulgation of uniformitarianism).Although quite varied opinions about the history and origins of life and of the Earth itself existed in the pre-Christian era, a divergence between Western and Eastern thought on the subject of natural history became more pronounced as a result of the extension of Bible.This forced coastal progradation along the western delta front where the Ganges was situated, and much of the river's fine-grained discharge bypassed the subaerial delta and formed a prograding deltaic clinoform on the shelf.Concurrently, Brahmaputra sediments were sequestered to an inland tectonic basin, thus starving the adjacent shoreline and leading to transgression along the eastern delta.This required that the Earth be conceived of as a static, unchanging body, with a history that began in the not too distant past, perhaps as little as 6,000 years earlier, and an end, according to the scriptures, that was in the not too distant future.This biblical history of the Earth left little room for interpreting the Earth as a dynamic, changing system.
Fossils help geologists establish the ages of layers of rock.
Unlike many other delta systems, subsidence in the subaerial G–B delta is not dominated by compaction, but rather by plate-driven tectonic processes that generate rates up to 4 mm/year.
Overall, the huge sediment load, tectonic subsidence, major seismic events, and a nearshore canyon system have led to widespread sediment dispersal and sequence formation across the subaerial delta, shelf, and deep-sea Bengal Fan throughout the Late Quaternary.
Evolution of the tectonically active Ganges–Brahmaputra (G–B) system reveals important similarities and differences with other deltas.
Overall facies succession follows that of basic models, progressing from an alluvial valley to coastal marine delta front to a prograding subaerial delta plain.radiometric dating, a method of age determination based on the principle that radioactive atoms in geologic materials decay at constant, known rates to daughter atoms.