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Kitava is the most easterly island of the Trobriand group. It is an uplifted coral atoll, oval in plan, with a maximum diameter of 4 1/2 miles. The centre of the island is swampy and surrounded by a rim that reaches a height of 142 m. Caves occur in various parts of the rim and several have been described in a previous article (Ollier and Holdsworth, 1970). One of the caves, Inakebu, is especially important as it contains the first recorded cave drawings from the Trobriand Islands. Inakebu is situated on the inner edge of the island rim at the north-eastern end of the island. Map 1 shows the location of the cave on Kitava Island. Map 2 is a plan of the cave, surveyed by C.D. Ollier and G. Heers. The location of the cave drawings is shown on the plan. Inakebu is a "bwala", that is a place where the original ancestor of a sub-clan or dala is thought to have emerged from the ground. The bwala tradition is common throughout the Trobriands and neighbouring islands. It has been described by many writers on the anthropology of the area, and was summarised in Ollier and Holdsworth (1969). The people believe that if they enter such places they will become sick and die. Until November, 1968, no member of the present native population had been in the cave, though there is a rumour that a European had entered it about 20 years before, but turned back owing to lack of kerosene. It must be admitted that this tale sounds rather like the stories one hears in Australia that Aborigines were afraid of the dark caves and therefore did not go into them. In fact, the many discoveries in the Nullarbor Plain caves show that they did, and the cave drawings in Inakebu show that someone has been in this cave. The point is that it does not seem to be the present generations who entered the caves but earlier ones; people from "time before" as they say in New Guinea. The first known European to enter the cave was Gilbert Heers, a trader in copra and shell who lived on the nearby island of Vakuta. He went into the cave on 8 November 1968 accompanied by Meiwada, head of the sub-clan associated with Inakebu, who had never been inside before. Heers and Meiwada investigated the two outer chambers but then turned back because they had only poor lights. They returned with better light on 15 November. Since they had not become sick or died, they then found seven other men willing to accompany them. They found the narrow opening leading to the final chamber, and discovered the drawings. None of the men, many of whom were quite old, had ever seen the drawings or heard any mention of them before. The drawings are the only indication that people had previously been in this deep chamber. There are no ashes or soot marks, no footprints, and no pottery, bones or shells such as are commonly found in other Trobriand caves, though bones and shells occur in the chamber near the entrance. With one exception, the drawings are all on the same sort of surface, a clean bedrock surface on cream coloured, fairly dense and uniform limestone, with a suitably rough texture. Generally the surface has a slight overhang, and so is protected from flows or dripping water. On surfaces with dripstone shawls or stalactites, the drawings were always placed between the trickles, on the dry rock. We have found no examples that have been covered by a film of flow stone. The one drawing on a flow stone column is also still on the surface and not covered by later deposition. A film of later deposit would be good to show the age of the drawings, but since the drawings appear to have been deliberately located on dry sites the lack of cover does not indicate that they are necessarily young. There are stencil outlines of three hands, a few small patches of ochre which do not seem to have any form, numerous drawings in black line, and one small engraving.
The Trobriand group of coral islands is situated a hundred miles off the north-east coast of Papua and north of the D 'Entr'ecasteaux Islands. In previous papers we have described caves on Kiriwina (the main island), Vakuta and Kitava (see References). We now describe caves of Kaileuna and Tuma (see Figures l and 2). In August 1970, we spent one week of intensive search for caves on these two islands, making our headquarters in the copra store in the village of Kadawaga. Kaileuna island is six miles long and almost four miles wide, and supports a population of 1,079 (1969 Census). It is separated from the large island of Kiriwina by a channel two miles wide between Mamamada Point and Boll Point, though the main village of Kadawaga on the west coast of Kaileuna is 18 miles from Losuia and 14 miles from Kaibola. The island is generally swampy in the centre with a rim of uplifted coral around the edge. We were assured that the correct name of the island is Laileula, but since Kaileuna is used on all previous maps it is retained here. However, we prefer Kadawaga to the Kudawaga or Kaduwaga that appear on some maps. The inhabitants are of mixed Melanesian-Polynesian Stock, who are almost totally self-supporting, being in the main farmers and fishermen. The yam (taitu) constitutes the staple crop and the harvest is still gathered in with ceremonies unchanged for centuries. There is great competition among families for the quantity and quality of the crop, which is displayed firstly in garden arbours (kalimonio), later in the village outside the houses; traditionally styled yam huts (bwaima) are then constructed to display the harvest until the next season. The transfer of yams from the garden to the village is occasion for a long procession of gatherers to parade through the village blowing conch shells and chanting traditional airs (sawili) to attract the attention of villagers to the harvesting party, After storage of the harvest, a period of dancing and feasting (milamala) continues for a month or more, Traditional clothing is the rule, Women and girls wear fibre skirts (doba), most of the men, especially the older ones, wear a pubic leaf (vivia) made from the sepal of the betel nut palm flower (Areca catechu Linn.). Tuma, the northernmost of the main islands in the Trobriand group, is six miles long and less than a mile wide. It is a low ridge of coral with swamps in the centre and along much of the western side. The island has been uninhabited since 1963 when the last few residents abandoned it and moved to Kiriwina, but it is still visited from time to time by other islanders who collect copra and fish. Tuma is believed by all Trobriand Islanders to be inhabited now by the spirits of the dead. It is also generally believed that Tuma is the original home of the TrobIiand ancestors; these ancestors are also said to have emerged at Labai Cave on Kiriwina Island, and from many other places of emergence or 'bwala". Lack of consistency in the legends does not appear to concern the Trobrianders very much. The cave maps in this paper are sketches based mainly on estimated dimensions, with a few actual measurements and compass bearings. Bwabwatu was surveyed more accurately, using a 100 ft steel reinforced tape and prismatic compass throughout.
In a previous paper (Ollier and Holdsworth, 1970) we described the island of Kitava and many of the caves on the island. This note supplements that account and describes caves and related features discovered during a brief expedition to the south of the island (Figure 1) in 1971. Kitava is a coral island with a number of terraces and reaches a height of 466 feet. There is a central depression in the top of the island, the site of the lagoon before the reef was uplifted. Some caves are associated with the rim of the island, a few occur on mid-slopes, and others are found along the sea cliffs. Many of the caves have been used for burial of human remains, sometimes associated with pots, clam shells or canoe prows. Canoe prow burials are reported here for the first time. Some caves are associated with megalithic structures and legends of the origin of the various sub-clans (dala) of the island.
Wellington Caves, New South Wales (figure 1), have attracted scientific attention for more than a century, largely through discoveries in the cave sediments of bones from extinct animals. These bone discoveries provided impetus for a number of early speculations about the geomorphology of the caves area and its relationship to the caves. Notable among these was the conjecture of Mitchell (1839) that the valley floor sediments of the Bell River and the cave fills had been deposited during a marine transgression about one million years ago. The first systematic geomorphological work was carried out by Colditz (1943), who argued for two distinct relict erosion levels in the Bell Valley; the older level was assigned to the Lower Pliocene and the younger to the Upper Pliocene. Colditz considered that these levels provided evidence for two phases of uplift in late Tertiary times. More recently Frank (1971) made detailed studies of the cave sediments, and devoted some attention to landscape evolution. He believed that the Bell River had been captured by Catombal Creek, during the late Pliocene or early Pleistocene.
The general objective of this work was to develop a basic understanding of the karst hydrology, the nature and origin of the caves, the water chemistry, the surface geomorphology, and relationships among these aspects for a high relief tropical karst region having a thick section of limestone. The Valles-San Luis Potosí region of northeastern México, and in particular, the Sierra de El Abra, was selected for the study. A Cretaceous Platform approximately 200 km wide and 300 km long (N-S) delimits the region of interest. A thick Lower Cretaceous deposit of gypsum and anydrite, and probably surrounded by Lower Cretaceous limestone facies, is overlain by more than 1000 m of the thick-bedded middle Cretaceous El Abra limestone, which has a thick platform-margin reef. The Sierra de El Abra is a greatly elongated range along the eastern margin of the Platform. During the late Cretaceous, the region was covered by thick deposits of impermeable rocks. During the early Tertiary, the area was folded, uplifted, and subjected to erosion. A high relief karst having a wide variety of geomorphic forms controlled by climate and structure has developed. Rainfall in the region varies from 250-2500 mm and is strongly concentrated in the months June-October, when very large rainfalls often occur.
A number of specific investigations were made to meet the general objective given above, with special emphasis on those that provide information concerning the nature of ground-water flow systems in the region. Most of the runoff from the region passes through the karstic subsurface. Large portions of the region have no surface runoff whatsoever. The El Abra Formation is continuous over nearly the whole Platform, and it defines a region of very active ground-water circulation. Discharge from the aquifer occurs at a number of large and many small springs. Two of them, the Coy and the Frío springs group, are among the largest springs in the world with average discharges of approximately 24 m³/sec and 28 m³/sec respectively. Most of the dry season regional discharge is from a few large springs at low elevations along the eastern margin of the Platform. The flow systems give extremely dynamic responses to large precipitation events; floods at springs usually crest roughly one day after the causal rainfall and most springs have discharge variations (0max/0min) of 25-100 times. These facts indicate well-developed conduit flow systems.
The hydrochemical and hydrologic evidence in combination with the hydrogeologic setting demonstrate the existence of regional ground-water flow to several of the large eastern springs. Hydrochemical mixing-model calculations show that the amount of regional flow is at least 12 m³/sec, that it has an approximately constant flux, and that the local flow systems provide the extremely variable component of spring discharge. The chemical and physical properties of the springs are explained in terms of local and regional flow systems.
Local studies carried out in the Sierra de El Abra show that large conduits have developed, and that large fluctuations of the water table occur. The large fossil caves in the range were part of great deep phreatic flow systems which circulated at least 300 m below ancient water tables and which discharged onto ancient coastal plains much higher than the present one. The western margin swallet caves are of the floodwater type. The cave are structurally controlled.
Knowledge gained in this study should provide a basis for planning future research, and in particular for water resource development. The aquifer has great potential for water supply, but little of that potential is presently used.
Work done at Bungonia since 1972 has filled gaps in our knowledge of this area. Water tracing has proven the earlier interference that the waters of all the major caves of the Lookdown Limestone and the uvula containing College Cave go to Efflux. Geological remapping shows that faulting allows these connections all to lie in limestone and accounts for the drainage of B4-5 away from the gorge. A 45m phreatic loop identified in Odyssey Cave, exceptionally large for south-eastern Australia, is also accounted for by the geological structure. Phoenix Cave has two successive cave levels similar to those of B4-5. The perched nature of the Efflux now finds a structural control in that the Folly Point Fault has interposed impervious beds between this spring and the gorge. Further analysis of the evidence relating the age of uplift and incision in the Shoalhaven and its tributaries strengthens the case for setting these in the lower Tertiary whereas most of the caves cannot be regarded as other than young. The geological remapping can partly account for the age discrepancy between underground and surface forms found at Bungonia.
Investigation of two King Island sea caves developed in quartzitic rocks shows them to contain a wealth of clastic and chemical sediments. Clastic sediments consist of wave-rounded cobbles, debris cones, and angular rock fragments produced by frost weathering and crystal wedging. Chemical deposits include a variety of calcium carbonate speleothems and also gypsum occurring as wall crusts and blisters. The latter appear to be a speleothem type of rare occurrence. Growth of gypsum is responsible for some crystal wedging of the bedrock. Three basal stalagmite samples have been dated by the Th/U method indicating Late Pleistocene as well as Holocene speleothem growth. The caves are believed to have formed by preferential wave erosion during the Last Interglacial in altered and fractured quartzites. The evidence for pre-Holocene evolution of sea caves and geos in the Tasman region is summarised. Tasmania and the Bass Strait Islands provide a particularly favourable environment for the preservation of relict landforms on rocky coasts because of Late Quaternary uplift. The potential of further studies of sea caves to test two recently advanced archaeological hypotheses is discussed.
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