Photo Tour of Java
Table of Contents
PHOTO 1: A physiographic and bathymetric map of western Indonesia. The Homo erectus area of eastern Java (lower center) includes volcanic mountains, coastal districts, and a variety of intermediate settings. The area lies at the southeast edge of a broad shallow sea (lightest blue), the Java Sea, which is bordered by the tropical lowlands (green) of Sumatra (left) and Kalimantan (Indonesian Borneo; center).
PHOTO 2: A typical eastern Java scene --
Mount Lawu volcano seen from the town of Ngawi on the Solo River, East Java.
The 3265-m high peak is surrounded by a broad, low relief volcanic apron
that supports intensive rice agriculture (foreground). See the Maps
of Indonesia by Peter Loud for topographic maps.
PHOTO 3: The volcanic peaks and nonvolcanic uplands of the hominid-producing area are drained by Java's largest rivers, the Solo and Brantas Rivers. Waterways of this kind appear to have been part of the landscape a million years ago when Homo erectus roamed Southeast Asia. Here, the lower Brantas River (near Jombang) carries volcanic sand similar to that found in the hominid-bearing deposits of Plio-Pleistocene age. Hand dredging not only recovered sand but the skull of a Homo sapiens (foreground on the river bank). Many Homo erectus fossils appear to have been deposited in similar geologic contexts.
PHOTO 4: In addition to volcanic peaks and sandy rivers, the Plio-Pleistocene environment of eastern Java contained quiet, muddy shorelines on north-facing coasts and an open-ocean coast along the Indian Ocean to the south. A modern example of the former type of shore is shown here along Madura Strait. Mangrove forests occur in the vicinity, and pollen of mangrove plants are found in the Plio-Pleistocene.
PHOTO 5: Today, eastern Java is principally rice fields and teak plantations. Extensive forests are described by early European travelers and scientists. Partially on the basis of this evidence, it is believed that the vegetation in the prehistoric Holocene was dominated by moist-deciduous forests. A present-day example of a moist forest is shown here from the Southern Mountains of East Java.
PHOTO 6: Also present in the prehistoric
Holocene were dry-deciduous forests such as this example from easternmost
Java. The photo was taken at the end of the dry season (October) when foliage
is at a minimum.
PHOTO 7: Sangiran Dome, near Surakarta (or Solo) in eastern Central Java, has produced far more hominid fossils than any other Plio-Pleistocene outcrop. The dome exposes about 110 m of Early Pleistocene lagoonal and lacustrine mudstone (the Pucangan Formation), portions of which have produced hominid fossils. The overlying series of cross-bedded sandstones, claystones, and tuffs, which amount to about 50 m of section (Kabuh Formation), has yielded more Homo erectus fossils and a few lithic artifacts. The volcanic sandstone shown here is interbedded with thin pebbly and tuffaceous-lenses. See "Solo-Sangiran-Kedungombo Excursion" at the Indonesian Geology Resources (1992 Sangiran Guide).
PHOTO 8: The vast majority of early hominid
fossil from Java is cranial material. The most complete is "Sangiran
17" ("Pithecanthropus VIII") from the Kabuh Formation.
PHOTO 9: East of Sangiran Dome and extending for a distance of over 140 km in nearly a continuous exposure is an outcrop belt of hominid-producing sediments that the author refers to as the East Java Hominid Outcrop Belt (EJHOB). The three most important hominid sites in the EJHOB are (1) the Trinil hominid site, where Eugene Dubois found the type Pithecanthropus erectus in 1891, the Kedung Brubus area where Dubois' crew had recovered hominid material a year earlier, and the Mojokerto (or Perning) site, which is the easternmost Homo erectus find in Asia and according to Swisher et al. (1994; Science, 263/25) appears to be the oldest hominid fossil yet discovered outside of Africa. The Mojokerto/Perning Homo erectus is also the earliest hominid remains found anywhere in a marine depositional sequence. This photo shows the terrain in the vicinity of the Mojokerto locale, where there are numerous outcrops of sandstone in stream beds, road cuts, quarries, terrace walls (background), and hill sides (foreground).
PHOTO 10: The hominid-producing sequence in the EJHOB (see Photo 9) consists of two dominant lithofacies - a volcaniclastic facies and a marine-mudstone facies. The second one only occurs in the eastern part of the belt. Andesitic "breccia" and cross-bedded volcanic sandstone (Photo 11) typify the volcaniclastic facies, and indicate derivation from volcanoes like those still present in medial eastern Java. For many decades, the "breccia" has been interpreted as volcanic mudflow (lahar) deposits. Outcrops of the "breccia," shown here from exposures in the bed of the Solo River at Ngawi, not only include pebble and boulders of volcanic rock but also large slabs of contorted volcaniclastic sediments that were ripped up by the mudflows.
PHOTO 11: Cross-bedded sandstone of the volcaniclastic facies is shown here from an extensive quarry near Kabuh in the eastern part of the EJHOB (see Photo 9 for definition). This sandstone occurs in the older of the two formations making up the EJHOB, the Pucangan Formation, but similar sandstone typifies the younger Kabuh Formation also. Note the similarity of the lithofacies shown here to the prolific hominid bearing sandstone pictured in Photo 7.
PHOTO 12: The photo shows the reconstructed
skeleton of a Plio-Pleistocene water buffalo (Bubalus) that is on display
in the geological museum at Bandung. The hominid-bearing sequence of eastern
Java contains many plant and large-vertebrate fossils. The plant remains,
which include leaves, wood, nuts, and fruit, as well as pollen and spores,
represent rain forests, swamp forests, mangrove forests, disturbed forests,
montane forests, and deciduous forest, and possibly the existence of grass-dominated
landscapes. The vertebrates include nonhuman primates - orangutan, gibbon,
macaque, and leaf monkey. Carnivores are tiger, leopard, large-tooth cat,
hyena, wild dog, bear, otter, and civet. Elephantids include both elephant
and Stegodon. Ungulates are hippopotamus, rhinoceros, tapir, pig, Asian
buffalo, wild cattle (banteng), an endemic ox, antelope, several species
of deer, muntjak, and mouse deer. Anteater, turtle, crocodile, and fish
also occur. Porcupine, rabbit, rat, and several bird genera are also known.
The fauna of Java lacked horses, camels, and giraffes - elements common