ABSTRACTS / RESUMES - Comitato Glaciologico Italiano

the intermontane basins. The anomalous position of the hi- .
ghest summit line of the chain instead, results from the interaction
of these active, tectonic factors with a passive
one, i.e lithology, which drives the highest summit line on
more conservative calcareous units outcropping on the west
side of the chain.
DIANA E. ANDERSON & STEPHEN G. WELLS
Latest Quaternary lakes in Death Valley, California, USA:
paleogeography and high-stands
Quaternary Sciences Center, Desert Research Institute,
p.o. box 60220, Reno, NV 89506, USA
Death Valley basin, in south-eastern California, USA, was
the terminus for the Owens, Mojave and Amargosa rivers
during the Quaternary. Lake-building episodes in the basin,
collectively referred to as Lake Manly phases, were related
to input from these drainages, runoff from local highlands,
and groundwater discharge. These lake phases are
recorded in landforms and surficial deposits surrounding
the basin, and in sedimentary sequences beneath the floor
of Death Valley (Hunt & alii, 1966; Hooke, 1972; Hunt
1975; Lowenstein, 1994; 1996). A series of ten shallow
«26 rn) cores taken from Devil's Speedway south to the
Confidence Hills (a 75 km transect) in southern Death
Valley, yield information on the paleogeography and lake
history of the basin during the past 40,000 years BP. Four
cores were dated using 14C_AMS on bulk organic fraction;
conventional ages are reported here. Lake deposits were
defined following Smith (1991).
The northernmost core, DVDP96-10, from Devil's Speedway,
on the northern periphery of Badwater Basin, is 18.7
m long and is floored in alluvial fan deposits. Lake deposits
were identified from approximately 11-16 m depth
(100-95 m bsl elevation), dating to 12,160±80 BP (dated sample elevation at 87 m bsl). The
upper 2.5 meters of the core is dominated by playa facies.
The Tule Springs core, DVDP96-9, contains evidence of
lake from 14,450±60 to 9,780±60 BP (86-82 m bsl elevation),
with shallow lake and distal alluvial fan deposits preceding
the lake deposits and distal alluvial fan/playa deposition
subsequent to the lake stand. Core DVDP96-6, from
Butte Valley Junction, contains evidence of a lake stand
dating from approximately 19,000 to 12,000 BP (86-79 m
bsl elevation) with an earlier lake stand dating to >26,200
±150 BP (dated sample elevation at 92 m bsl), These two
lake stands are separated by an intermittent/shallow lake
interval. The upper 12 m of the core are dominated by
mudflat and distal alluvial fan facies. The southernmost core,
DVDP96-2, shows evidence of a single lake stand at approximately
19,530±80 BP (dated sample elevation at 7 m
elevation). The core was taken from the modern Amargosa
River channel and contains fluvial sands and gravels above
and below the lake deposits. These dated cores suggest the
presence of at least two lake stand phases in Death Valley
basin between