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The M$\o$ller tetrad gravitational energy-momentum expression was recentlyevaluated for a small vacuum region using orthonormal frames adapted to Riemannnormal coordinates. However the result was not proportional to the Bel-Robinsontensor $B_{\alpha\beta\mu\nu}$. Treating a modified quasilocal expressions in asimilar way, we found one unique combination that gives a multiple of$B_{\alpha\beta\mu\nu}$ which provides a non-negative gravitationalenergy-momentum in the small sphere approximation. Moreover, in addition to$B_{\alpha\beta\mu\nu}$, we found a certain tensor$S_{\alpha\beta\mu\nu}+K_{\alpha\beta\mu\nu}$ which gives the same"energy-momentum" density in vacuum. Using this tensor combination, we obtainedan infinite set of solutions that provides a positive gravitational energywithin the same limit.

Gravitational energy in small regions for the quasilocal expressions in orthonormal frames