Geology Reference
In-Depth Information
Fig. 21.30
Facies stratigraphy of the Sorkh Shale Formation in
the Tabas rift basin, east central Iran (locality 4 in Fig.
21.25
).
Note that, except for the upper part of the transgressive systems
tract, the sequence is entirely composed of tidal fl at facies inter-
calated with storm deposits containing intraclasts, ooids and bio-
clasts derived from distal areas of the basin (not all storm layers
are shown). Note also that the small-scale shallowing-upward
cycle stacking pattern is retrogradational in the transgressive and
progradational to aggradational in the highstand systems tracts,
respectively (for comparison with the distally located Veresk sec-
tion see Fig.
21.29
). Black and gray triangles represent transgres-
sion and regression, respectively. Abbreviations:
HST
highstand
systems tract,
mfs
maximum fl ooding surface,
SB
sequence
boundary,
TST
transgressive systems tract
