If this occurs within the same deposition environment, one would expect a change from coarser grain size (deltaic) to finer grain size (lacustrine).

Maybe go and get Gary Nichols (1999) Sedimentology. Possibly there are newer editions out there by now.

Lots of different things can be used to differentiate lacustrine and deltaic sediments - generally, one can expect deltaic sediments, if exposed at outcrop to a large enough scale, to have more variable sequence stratigraphy and lots of structures of different hierarchical orders. Lacustrine sediments can display complex stacking patterns and variable sequence stratigraphy based on factors of accommodation, climate and tectonism, but generally, one can expect lacustrine environments to be more closely associated with laminated, fine-grained sediments. Some good indicators include:

Lacustrine Environments:

Strong lamination, potential varved sediments

Relatively fine-grained, though occasional storms may introduce coarser sediments and/or detritus

Depending on the catchment, endogenic mineral precipitation (e.g. carbonate, gypsum)

Deltaic Environments:

Rapid lateral facies changes, especially in areas where deltaic distributaries and floodplains overlap

Variable facies from the delta source to the mouth

Complex sequence stratigraphical architecture

Lateral accretion surfaces and cross-bedding, particularly in distributary channels

One must also consider that deltas can be found in some lacustrine environments where larger rivers distribute sediment into the environment - see Fanetti et al. (2007).

As Martin suggested, Nichols version of Sedimentology will be very useful here.

Some other references:

Moore (1966) - Deltaic Sedimentation

Schnurrenberger et al. (2003) - Classification of lacustrine sediments based on sedimentary components