The relative roles of tectonic uplift and climate oscillation in pacing dust production and routing in continental interiors remain a central debate. We contribute to resolving this controversy with a high-resolution, nearly 0.81 Myr-long dust-provenance record from a loess-palaeosol sequence on the northern Qilian slope, northeastern Tibetan Plateau (NTP), based on 2060 detrital zircon U-Pb ages. Our record reveals binary mixing between NTP and Gobi-Altay Mountains (GAMs) sources. Critically, dust-provenance shifts are locked to pulses of uplifted river-terrace formation and show weak correlation with glacial-interglacial cycles. This provides unambiguous evidence that the tectonic pulses, not the monsoon rhythm, dominated dust-source variations on million-year timescales. We identify the uplifting Qilian Mountains foreland as the key tectonic gatekeeper that modulated dust provenance mixing in direct response to tectonic pulses. A compilation of regional detrital zircon U-Pb provenance data, spanning from the NTP to the central Chinese Loess Plateau (CLP), reveals a systematic spatial gradient: the signature of tectonic control over dust sourcing strengthens toward the source areas, while climatic modulation increases downwind. These tectonically-driven processes generated the highest-frequency oscillations in dust sourcing yet documented in and around the NTP. Our findings transform the NTP margin into a benchmark for tectonically-paced dust provenance dynamics, and offer a revised framework for interpreting dust archives in terms of provenance and for coupling tectonics with global sediment cycles.