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Using observations from Solar Dynamics Observatory, we studied an interestingexample of a sigmoid formation and eruption from small-scale flux cancelingregions of active region (AR) 11942. Analysis of HMI and AIA observations inferthat initially the AR is compact and bipolar in nature, evolved to shearedconfiguration consisting of inverse J-shaped loops hosting a filament channelover a couple of days. By tracking the photospheric magnetic features, shearingand converging motions are observed to play a prime role in the development ofS-shaped loops and further flux cancellation leads to tether-cuttingreconnection of J-loops. This phase is co-temporal with the filament risemotion followed by sigmoid eruption at 21:32 UT on January 6. The flux roperises in phases of slow (v$_{avg}$ = 26 km~s$^{-1}$) and fast (a$_{avg}$= 55ms$^{-2}$) rise motion categorizing the CME as slow with an associated weakC1.0 class X-ray flare. The flare ribbon separation velocity peaks at aroundpeak time of the flare at which maximum reconnection rate (2.14 Vcm$^{-1}$)occurs. Further, the EUV light-curves of 131, 171\AA~have delayed peaks of 130minutes compared to 94\AA~and is explained by differential emission measure.Our analysis suggests that the energy release is proceeded in a much long timeduration, manifesting the onset of filament rise and eventual eruption drivenby converging and canceling flux in the photosphere. Unlike strong eruptionevents, the observed slow CME and weak flare are indications of slow runwaytether-cutting reconnection where most of the sheared arcade is relaxed duringthe extended post phase of the eruption.

Formation and eruption of sigmoidal structure from a weak field region of NOAA 11942