A community has a fixed stock $X$ of oil that it has to consume over an infinite horizon. The utility function to be maximized is $$U=∑_t \delta^t \ln (C_t)$$ where $C_t$ represents consumption of the resource at time $t$. Also $\delta_t \in [0,1]$ is the discount factor for time $t$. Find the optimal consumption of at time $t$.
I have tried to apply Jensen's inequality since $\delta^t \ln (C_t)$ will be a concave function, but cannot figure out how to go beyond that.