Archaeological Method: Stratigraphy, Dating, and Interpretation

Archaeology reconstructs human history from material remains — pottery, tools, structures, faunal and floral remains, human skeletons — rather than texts. The foundational principle is stratigraphy: the law of superposition holds that, absent later disturbance, lower layers of soil and debris are older than layers above them. Careful excavation records the exact three-dimensional position of every artifact within its stratigraphic layer (context), because an artifact's meaning depends heavily on its association with other finds and its depth. Mortimer Wheeler, who directed the Archaeological Survey of India from 1944 to 1948, introduced rigorous grid-based excavation and section-drawing methods that transformed the technical standards of Indian archaeology, most famously at Harappa and Mohenjo-daro.

Dating methods used in Indian archaeology range from relative to absolute techniques. Relative dating includes seriation (ordering artifact types by stylistic change) and stratigraphic sequencing. Absolute or chronometric dating includes radiocarbon dating (measuring carbon-14 decay in organic material, effective up to about 50,000 years), thermoluminescence (dating when a mineral was last heated, useful for pottery and burnt structures), and, for much older sites, potassium-argon or optically stimulated luminescence dating of sediments. The application of radiocarbon dating from the 1950s onward revolutionized Indian prehistory by allowing absolute chronologies for sites like Mehrgarh and Harappan-era settlements rather than relying solely on cross-comparisons with Mesopotamian chronology.

Archaeological interpretation goes beyond dating to reconstruct past lifeways: settlement pattern studies map how sites are distributed across a landscape to infer trade networks, agricultural hinterlands, and urban hierarchies. Faunal and archaeobotanical analysis reveals diet and domestication histories — for instance, evidence from Mehrgarh in Balochistan shows some of the earliest evidence of wheat and barley cultivation and cattle domestication in South Asia, pushing back the timeline for Neolithic transitions in the region considerably earlier than once assumed.

Indian archaeology has also grappled with politically charged interpretive debates, most notably the Ayodhya excavations directed under court order in 2003, where archaeological findings regarding structures beneath the Babri Masjid site were mobilized in a highly contested legal and political dispute. This episode illustrates how archaeological method — however technically rigorous — operates within a social and political context that shapes which questions get asked, which excavations get funded, and how findings are publicly received and contested by different constituencies.

The ethics of archaeological practice in India also involve engaging with local and descendant communities, since excavation can disturb sacred sites, agricultural land, or living heritage. Scholars like Nayanjot Lahiri have written on both the technical history of Indian archaeology and its entanglement with colonial power, nationalist recovery projects, and contemporary heritage politics, showing that the discipline's tools cannot be separated from the social world in which they are deployed.