Shell beds are commonly preserved in
modern and ancient lacustrine rift settings and their taphonomy is
well understood, but the accumulation of disarticulated fish parts
in strandline settings is poorly understood. Hence, the Salton Sea
shorelines are important modern analogs for the buildup of
disarticulated fish parts. The Salton Sea accumulations are
compared, contrasted and integrated into an interpretation of
fish-part beds of the Triassic Newark basin in Pennsylvania.
Salton Sea shorelines consist of beach ridge surface morphology and
normal grading from the beach to the backshore. The most common
clast components in core samples are barnacles and disarticulated
fish parts. The cored deposits are characterized by normal graded
beds, but are doubly graded with two clast types within a single
depositional bed: First, the barnacles form a normally graded base
of each bed, followed near the top of the bed by smaller comingled
barnacles and the hydrodynamicly equivalent largest fish parts.
Second, the bed top consists of normally graded fish parts, with
isolated partially articulated fish fragments present across the
beach surface at the Salton Sea.
The composition and structure of the deposits of the modern Salton
Sea are comparable to fish kill beds from rare shoreline deposits of
the Triassic lacustrine Lockatong Formation. After death,
decomposition and bloating of the fish led to flotation. Fish
carcasses were driven shoreward by waves, probably storm-generated.
The remains were disarticulated and reworked as lag concentrations
that are recorded in the double normal grading of the
intraformational clasts (barnacle equivalent) and fish-parts. The
graded beds record the impact of the storm on the strandline and
coeval washover into the associated fluvial systems. Late partially
articulated fish fragments found at the top of the Triassic beds and
Salton Sea had not degassed and thus settled last.
Strandline deposits of the Salton Sea,
California: An integrated analogue for Triassic fish-part
conglomerates of the Newark Basin
Shell beds are commonly preserved in
modern and ancient lacustrine rift settings and their taphonomy is
well understood, but the accumulation of disarticulated fish parts
in strandline settings is poorly understood. Hence, the Salton Sea
shorelines are important modern analogs for the buildup of
disarticulated fish parts. The Salton Sea accumulations are
compared, contrasted and integrated into an interpretation of
fish-part beds of the Triassic Newark basin in Pennsylvania.