Interim Report

Introduction

The Mulu Caves 2007 expedition took place between January 15th and February 16th 2007. The expedition was the latest in a series of Anglo-Sarawak cooperative activities which commenced in 1977. A team of fifteen British cavers, with the close support of National Park staff and local porters, carried out exploration in southern G.Benarat and northern G.Api. A total of 25.8kms of cave passages were explored and surveyed: the total length of the Clearwater Cave System was extended to 151.4 km confirming its current status as tenth longest cave in the world.

This document represents a field summary of the achievements of the expedition. A full report, including cave surveys etc will be published in due course with copies to be provided to the Sarawak Authorities and the G.Mulu National Park Management.

Objectives

The expedition follows on from the recent series of explorations in Gunung Benarat and the northern end of Gunung Api. At the end of the 2005 expedition, the newly discovered Moon Cave (Gua Bulan) remained unfinished and a number of promising underground leads remained in Whiterock Cave (Gua Batu Putih) which was linked into the Clearwater System in 2005.

Primary objectives were therefore:

Gunung Benarat

  • To continue the exploration of Moon Cave.
  • To relocate and survey Gawai's Cave
  • To further explore Deliverance Cave
  • To carry out surface exploration and survey work to identify new entrances

Gunung Api

  • To continue the exploration of Whiterock Cave
  • To seek a connection between Solo and Clearwater Cave
  • To carry out surface exploration and survey work to identify new entrances

Outcomes

Gunung Benarat

Further exploration of Moon Cave

At the end of the 2005 expedition two important leads had been left unexplored. It was hoped that these would lead to a higher level of passages and possibly the large open entrance high in the cliff opposite Camp 5. Unfortunately this connection was not made and the elusive upper series remains for future explorers.

A concentrated effort, which required a small amount of digging to pass a draughting boulder choke, established a connection with Cobweb Cave. This now provides a link between Benarat Caverns, Moon Cave and Cobweb Cave which makes the Cobweb Cave System 50.5km long, the second longest cave in the Park and currently fiftieth longest cave in the world.

The total length of passages explored within Moon Cave was 3.7km.

Other objectives in Gunung Benarat

Due to the focus on cave exploration, these subsidiary objectives were not pursued.

Gunung Api

Exploration of Whiterock Cave

A major lead heading north was explored and found to end 373m from Camp 5 in a mass of calcite and boulders. Unfortunately no entrance was found and there was no sign of drafts, swifts, or other evidence that access to the surface would be possible. This area proved to be very remote and an extremely arduous trip for the exploration team. A subsequent trip discovered another passage 60m above this which almost duplicated the alignment of the lower passage and ended 360m from Camp 5 in similar calcite and boulders.

A great deal of new passages was discovered in the central areas of the cave infilling blank areas and creating links between previously surveyed areas of the cave.

The total length of passages explored in Whiterock Cave was 21.9km.

Exploration of Solo-Clearwater link

Following the BBC's Natural History Unit 'Expedition Borneo', filmed mid 2006, which included a trip into Solo, interest was kindled in the connection between Clearwater and Solo. During filming at the base of Solo, progress was made down a couple of short climbs and squeezes through boulders to a series of large chambers joined by calcited slopes. 200 metres of passage was found but not surveyed as exploration was curtailed during the filming. However there was physical and word of mouth evidence that a connection may have been made by a bird-nester from Clearwater to Solo.

At the start of the 2007 expedition a small team spent three days trying to establish the connection from Clearwater upwards, having firstly re-surveyed from the Goldwater River, on the surface, up into Revival. From Revival, extensive searches were made in the boulder chokes at the start of Beckoning Finger and at the southern end of the Dune Series. Unfortunately, no connection was made and no new passage found. The elusive connection may be more easily located from Solo downwards.

During this period a stone axe head was found and passed on to the Park authorities, together with details of its location.

Surface exploration and survey work to identify new entrances

Various expeditions have spent time exploring the foot-slopes of G.Api in the Melinau Gorge with limited success. Most discoveries have consisted of minor caves which are associated with marginal drainage. No large fossil passages have been explored. During previous expeditions surveys have been produced but these have never been correctly positioned such that subsequent expeditions are never certain whether their discoveries are new or whether an earlier expedition has been there before. This expedition went some way to tie in the known entrances by surveying the surface track to the major features of Bat Cave and Shelter Cave.

Surveying

All discoveries have been surveyed. The current best practice software tool for survey data is Survex (www.survex.com); prior to the start of the expedition all available survey data from previous expeditions as far back as 1978 has been processed to generate a computer model of the cave systems within G.Api and G.Benarat. In addition, a wire frame model of the surface features has been constructed, based on 1:50,000 topographical data to provide a three dimensional model of the two mountains with their associated cave systems, surface traverses, entrances and GPS fixed points. It is proposed that this model will be built on by future expeditions. All data has been provided to the National Park authorities.

Logistics

The expedition was based at Camp 5 by agreement with the Park Management.

Underground camps were established in Whiterock. This was necessary because the cave entrance is approximately 2 hours from Camp 5 and new exploration is at a substantial distance into the cave. All waste was removed from the camp sites. Cooking was carried out on portable gas stoves.

Staff and field logistics were provided by Tropical Adventure Sdn Bhd.

Acknowledgements

Members of the expedition are grateful for the support of the following:

  • The Sarawak State Secretary
  • The Chief Minister of Sarawak
  • The Director of Forests, Sarawak
  • Protected Areas & Biodiversity Conservation Unit, Sarawak Forestry Corporation
  • G.Mulu National Park Management & Staff
  • Brian and Sue Clark
  • Lyon Equipment Ltd, Ben Lyon
  • Conformance Ltd
  • Robert Bosch Limited
  • Jerry Wooldridge
  • Richard Hii and the staff of Tropical Adventure Sdn Bhd.
  • Dr Angela C Hare, for assistance with medical advice sheets etc.
  • Howard & Deb Limbert (Vietnam Caves) for loan of basic medical kit.

Expedition members were:

  • Jane Allen
  • Tim Allen
  • Colin Boothroyd
  • Dave Clucas
  • Dave Cowley
  • Tim Fogg
  • Pam Fogg
  • Dave Harley
  • Matt Kirby
  • Dave Nixon
  • Hugh St Lawrence
  • David Scott
  • Robbie Shone
  • Nick Williams
  • Mark Wright

  • Epoi Boi
  • Roland Gau
  • Syria Lejau
  • Jenny Malang
  • Jeffrey Simun
  • Paris Wan

Dick Willis

Co-ordinator, Mulu Caves 2007

dick@r-w-a.net

26th February 2007