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aggradation and dissection/progradation phases provided fan aggradation, under excess sediment supply transitions
probably during cooler wetter Pleistocene glacial conditions or during glacial-to-interglacial conditions. During
peak glacials the floor of the valley was occupied by a terminal pluvial lake (Lake Manley); Badwater playa is its
modern (partly spring-fed) shrunken remnant. Today's hyper-arid environment is subject to occasional storms, flash
floods and debris flows, adding sediment by debris flows from small steep catchments, channelised streamflows
from larger catchment feeder channels and through braided channels within fanhead trenches, and sheetfloods on
aggrading fans and distal fan surfaces.
Although fans are largely not coupled with adjacent environments, interactions between fan processes and other
environments are important for identifying past phases of fan evolution, interaction with the Amargosa fluvial
system in the southern section of the valley, the Badwater playa lake in the central section and dunefields to the
north. For a selection of Death Valley alluvial fan references see Denny (1965), Hunt and Mabey (1966), Hunt
(1975), Hooke and Dorn (1992), Dorn (1988), Blair and McPherson (1994a) and Blair (1999). For other illustrations
of Death Valley fans see Figures 14.2(d), 14.5(c,ii), 14.14(d) and 14.17.
In the years that followed there has been consolidation
of these themes (Hooke and Rohrer, 1977, 1979; Lecce,
1991; Blair and McPherson, 1994a, 1998; Blair, 1999),
but the response of fans to Quaternary climatic change
has emerged as a major theme (Dorn
et al
., 1989; Bull,
1991; Hooke and Dorn, 1992; Weissmann, Mount and
Fogg, 2002; Weissmann, Bennett and Lansdale, 2005).
This has been aided by development of understanding
of soil/geomorphic relationships (Gile, Peterson and
Grossman, 1966; Harden, 1982; Harden and Taylor, 1983;
Machette, 1985), desert varnish (Dorn and Oberlander,
1981, 1982; Dorn, 1988, 1994) and desert pavement
development, especially aiding the relative dating of fan
surfaces (Lattman, 1973; Wells, McFadden and Dohren-
wend, 1987; McFadden, Wells and Jercinavich, 1987;
McFadden, Ritter and Wells, 1989). Furthermore, increas-
ing knowledge of Quaternary environments in the Amer-
ican deserts (Grayson, 1993; Enzel, Wells and Lancaster,
2003), particularly in relation to the basin-centre pluvial
lakes (e.g. Adams and Wesnowsky, 1998, 1999), has
enabled research into fan-lake relationships to focus on
Quaternary fan dynamics (Harvey and Wells, 1994, 2003;
Ritter, Miller and Husek-Wulforst, 2000; Harvey, Wigand
and Wells, 1999; Harvey, 2005; Garcia and Stokes, 2006).
Dry-region alluvial fans occur in all the major dry-
land mountain regions of the world. Since the 1970s,
building on the American work, alluvial fan research
has developed in other dry regions. Only recently has
much attention been given to the dryland fans in South
America, in the Atacama Desert (e.g. Mather and Hartley,
2005; Hartley
et al
., 2005) and in the semi-arid lands of
the Argentinian Andes (Colombo, 2005; Robinson
et al.
,
2005). In Australia, Williams (1973) and Wasson (1974,
1979) described fan morphology and sediments in the
Flinders Ranges and elsewhere. In Asia, although there
the large and impressive fans in the Taklimakan Desert in
northwest China and other deserts in central Asia, in India
there has been some research. Of particular significance
is the recognition of enormous 'megafans', first described
for the Kosi fan (Gohain and Parkash, 1990), although not
really a dryland fan. A similar megafan, the Okavango
fan in southern Africa (Stanistreet and McCarthy, 1993),
has been described as a terminal fan, where the Okavango
River peters out at the margins of semi-arid northern
Botswana.
In the Middle East, there has been research in Israel
focusing on the interplay between tectonic, climatic
and base-level controls (Bowman, 1978, 1988; Frostick
and Reid, 1989; Gerson
et al
., 1993; Amit, Harrison
and Enzel, 1995). Elsewhere, there have been studies in
Kuwait (Al Sarawi, 1988), Turkey (Roberts, 1995), Iran,
(Arzani, 2005) and in the UAE and Oman (Al Farraj and
Harvey, 2000, 2004, 2005).
Apart from the ongoing work in the American West,
it is the drier parts of the Mediterranean region that have
provided the basis for many alluvial fan studies since
the late1970s. In North Africa, White (1991), White and
Walden (1994, 1997) and White
et al
. (1996) have pio-
neered two developments, the application of remote sens-
ing to mapping fan surfaces and the analysis of pedogenic
iron oxide geochemistry, as an aid to correlating fan sur-
faces. In the drier parts of Europe other studies include
those by Sorriso-Valvo, Antronico and Le Pera (1998) in
southern Italy, stressing topographic and tectonic controls,
and in Greece by Pope and Van Andel (1984), emphasis-
ing geoarchaeological implications, Nemec and Postma
(1993) and Pope and Wilkinson (2005), the latter stress-
ing tectonic and climatic controls and using OSL dating
among a range of sophisticated geotechnical methods.
There
