This paper presents a new structured parallel programming model, "SEQ of PAR", based on the Communication Closed Layer (CCL) principle of causal composition for parallel programs and Bird-Meertens formalism (BMF) of locality-based parallel computation. This model is to support for more general, architecture-independent parallel programming. It provides a structured approach to integrate task (or process) parallelism and data- parallelism in one framework. The well-founded algebra of CCL and BMF makes it also possible to derive, optimize and verify parallel programs through algebraic transformations. Experimental results show that it is very promising to adopt this programming model for getting efficient, portable parallel code.