Aspect-oriented software development (AOSD) techniques support systematic modularization and composition of crosscutting concerns. Though AOSD techniques have been proposed to handle crosscutting concerns at various stages during the software life cycle, there is a traceability gap between the aspects at the requirements level and those at later development stages. It is not clear what proof obligations about an aspect-oriented implementation follow from the initial aspectual requirements. This paper presents PROBE, a framework for generation of proof obligations for aspect-oriented systems from the initial aspectual requirements and associated trade-offs. The abstract proof obligations are expressed in standard linear temporal logic. Key components of the framework include an extended Ontology with parametric temporal formulas and functions, and extensive treatment of conflicts among requirements. The resultant temporal logic assertions, grouped into specifications of aspect implementations, can then be instantiated in terms of the implementation and verification tools.