Transcript Facies and Facies Models

Facies and Facies Models
What is a facies?
A sedimentary unit with consistent characteristics (lithology, grain size,
texture, structures, etc.) that formed under specific depositional
conditions.
What are facies models?
An idealized vertical succession of facies that would be expected from the
migration of depositional environments within a particular setting (e.g.,
sandy braided river model, wave-dominated delta model).
Walther’s Law
Rationale for interpreting vertical facies succession is based on Walther’s Law
Vertical succession of facies represents migration of laterally adjacent
depositional environments, unless there is evidence of erosion (unconformity)
Constructing a facies model:
1. Identify important surfaces
(especially erosional)
Constructing a facies model:
2. Interpret facies using knowledge
of sedimentary processes and
modern environments
Constructing a facies model:
3. Determine characteristic vertical
succession of facies