The Department of Geology, UWI, Mona Jamaica, in collaboration with the Office of Disaster Preparedness (OPD and the United Nations Development Program (UNDP) hosted a workshop on Landslide Hazard Mapping and Prediction at the Conference Room of the Natural Science Library, UWI. Mona, from January 4th to 14th, 1989.
Though the workshop was fairly well attended, particularly by the Jamaican delegates, it was felt that there should have been a greater participation from other countries of the Caribbean, particularly as the problem is common and ever present throughout the Caribbean.
Dr. Barbara Carby, Head of Planning and Research, Office of Disaster Preparedness, introduced the members of the panel and have a brief account of the role of the ODP in organising the sessions. In his opening address Prof.
Ken Magnus, Dean, Faculty of Natural Sciences, UWI, Mona, stressed the
importance of cooperation between the University and the wider community in achieving meaningful results in any venture. He voiced the sentiments of many, if not all of the participants, when he referred to the timeliness of the Workshop.
The Workshop extended over a two-week period and was conducted by Mr. Jerome V. de Graff of the USDA Forest Service. The aim of the workshop was to train participants in the several procedures and techniques involved in the different aspects of Landslide Hazard Assessment. Topics covered included:

1. Slope Stability Principles
2. Landslide Classification
3. Factor Analysis in Landslide Hazard Zonation
4. Investigation of Landslide Hazard
5. Landslide Risk Assessment
6. Geomorphic Factors
7. Aerial Photo Interpretation
8. Landslide Map Preparations and Interpretation
9. Preparation of Susceptibility Maps
10. Map Compilation.

It was felt that in some areas more in-depth work should have been done, particularly with reference to aerial photography and the actual compilation of the susceptibility maps. The use of computers in hazard investigation was omitted perhaps for want of time and it is to be hoped that at future workshops other modern aids would be introduced.
The workshop was a success in that participants received more than just technical training. There was valuable exchange of information amongst the participants, even those from the same country. Of particular significance is the important human resource technical base that has been established. Also coming out of the workshop was the formation of the 'Caribbean Landslide Working Group."

In concluding, I would like to suggest the following:

a) that a follow-up to this workshop be planned for say, approximately one year later.

b) that in any future workshop on Landslides the use of computers as an aid be considered a part of the sessions.

c) 'Prediction' be introduced into the programme.

Finally I would like to express my thanks to the Pan Caribbean Disaster Preparedness and Prevention Project (PCDPP) for making my attendance at the workshop possible.

2. RESOURCES, NATURAL HAZARDS AND THE GEO-SCIENCES IN THE CARIBBEAN

T. Jackson
(Department of Geology, UWI, Mona and R. Wright, Petroleum Corporation of Jamaica)

A feature of the recently concluded conference oil 'Recent Advances in Caribbean Geology" held at the University of the West Indies (Plate 3) was a panel discussion on the training and employment of geoscientists in the Caribbean.
The conference, which was held from November 18-20, was sponsored jointly by the Geological Society of Jamaica and the Department of Geology, UWI. and formed part of the UWI's 40th Anniversary celebration.
Taking part in the discussion was a group of geoscientists who are currently working in the Caribbean. A number of important issues were raised by the panel and audience during the discussion. For example, the creation of regulations making it necessary to certify "professional geologists" was suggested by Dr. Grenville Draper of Florida International University. He pointed out that professional registration, as is required in the USA, will encourage the use of the geological input into land management by planners, decision makers and private citizens. This has been done recently in respect to engineers in Jamaica. To reinforce this point. Mr. Neville McFarlane (Jamaica Gypsum) suggested that Caribbean countries should enact regulations preventing the development of land without a geoscientific report.
Mr. McFarlane noted that many geologists tend to disappear into the workforce and do not produce effective science. Many geology students in Jamaica and other Caribbean countries either do not go into the profession on graduation or leave after a few years for more lucrative positions in banking, business and insurance industry. Grantley Walrond of Guyana regarded this as poor resource allocation - we should not train geologists to be something else," he said.
It was agreed that employers in the public and private sector should fund specialised research projects in which they requite results so that postgraduate students can acquire funding for work towards a degree as well as produce meaningful and immediately applicable research. Dr. Jackson (UWI) added that the Department of Geology operated within certain constraints, one being the small number of academic staff and the other the limited research equipment available at the UWI. He felt that in order to mount research in the more applied areas of the geo-sciences support must come from the alumni, public and private sector organizations. This support could be in the form of funding a Personnel Chair in Geology or Research Fellowship and/or new equipment.
The meeting felt that the Depart­ment of Geology should teach short courses in engineering geology, industrial mineral resource development and hydrogeology preferably during the summer period. For this reason it was recommenced that Summer Schools be established to use the University facilities in the vacant holiday period and that teaching staff from universities and special institutions abroad be provided in addition to local expertise. Mt. Michael White (Hydrology Consultants) indicated that perhaps the most urgent need is for courses in water resources because of the shortage and uneven distribution of water spatially within most islands of the Caribbean. Water - a renewable resource - was seen by Dr. Raymond Wright (PCJ), as "a more immediate and important pro­blem to Caribbean countries than the impending finite end of non-renewable resources such as oil and gas and metals." He felt that ultimately there should be Water Resource Institute servicing the training and research needs of the entire Caribbean region.
Professors Lewis and Robinson, both former lecturers of the Geology Department at UWI, indicated that there were a number of universities in the Spanish speaking Caribbean that have been teaching and conducting geological investigation for a long time. Such universities exist in the Dominican Republic, Puerto Rico, Mexico, Venezuela, Colombia, Costa Rica and Cuba. It was suggested that there should be more collaborative teaching and research efforts with some of these universities and the UWI.
A consensus emerging from the meeting was that geologists must play a leading role as the Caribbean region tackles investigations on its mineral and energy industries, and on reduction of vulnerability to, and effects of, natural hazards. The United Nations has desig­nated the 1990s as an International Decade of Natural Hazard Reduction, during which a concerted effort will be made to reduce loss of life and damage caused by such natural catastrophes as earthquakes, floods, volcanic eruptions, hurricanes and landslides. Geologists have an important role to play, not only in conducting research but also in communicating information clearly and precisely to public officials, urban planners and architects.
Thus, the meeting agreed, geoscientists will have to learn to teach a wider user audience, as geology becomes more and more a scientific force that influences and stimulates social and economic development in the Caribbean. There is a need to promote better understanding and communication between the producers and users of geological information.

This report represents a summary of activities undertaken in the Venezuelan Republic during the period October20 to November 16, 1988.
The main aims of the exercise were to:

(i) Observe and gain first hand experience in the methodology used at the Ministry of Energy and Mines in assessing geotechnical problems in the Republic.

(ii) Study the problems as they exist (in Venezuela); compare ant contrast them with the Trinidad situation. From the Venezuelan study, select appropriate methodology and solutions to apply to the Trinidad situation.

(iii) Examine the general geology of Venezuela with a view to selecting specific geologic lithologic units that beat a similarity to the Trinidad geology with a view to examining specific problems within specified lithologic units.

METHODOLOGY
The assignment was carried out in two parts:
(I) Office Study:
(a) Review of the general geology and geography of Venezuela.

(b) Examination of specific geologic and geographic regions.

(c) Study of the methodologies used in geotechniques in Venezuela.

(2) Field Study.

(a) Visits to Caracas Metropolitan areas, showing areas of extreme geotechnical problem.

(b) Visit to different sites repre­senting various geotechnical problems.

(c) Visits to cities in the Los Andes Region.

The assignment commenced with a review of the general geology and geography of the Republic of Venezuela. This was undertaken with a view to obtaining an overall picture of the country. Later on, the geology of specific areas was studied to gain an insight into the contributory role of geology in geotechnical problems. This programme of study was to be a continuing exercise, undertaken simultaneously with using the methodology as utilised by the Ministry of Energy.

OBSERVATIONS

Caracas - In the Caracas Metropolitan area, the geology is similar to that of the Northern Range of Trinidad i.e., phyllite, schists, quartzites, marble. The area is extensively folded and faulted again as is the case in
Trinidad.
Because of the pressures of urban growth (Caracas has a population greater than 5 million) the city has spread from the alluvial terraces and fans to the slopes of the surrounding mountains, which are generally steep. Given the existing lithologies, struct­ures, and morphology of these areas, problems of immense proportions are bound to arise. Investigating the geotechnical properties of these areas, predicting the stability of the slopes with a view to minimising the risk and costs involved, are the main concerns of the Geotechnique Unit of the Ministry. The techniques include (1) field (2) lab and (3) desk work, utilising the tools of geology, geography and engineering.

SITE VISITS

Caracas Region - On visits to the Metropolitan areas, in particular the Santa Monica district, numerous land­slides, rock falls and other evidence of mass movements were observed. The Santa Monica area is a middle to upper class residential district. The homes are mainly architect-designed, beautiful and costly. Many houses have been destroyed or severely damaged, and several more are in imminent danger of destruction. The study of the area has been completed and the analysis shows that the area is generally unstable and before any construction work is under-taken, a study of the geotechnical report is a necessity. Attempts are being made to stabilize the slopes. Measures adopted include shot crete retaining walls, with anchors, gabion baskets, rubble masonry walls, terraces and com­binations of two or more methods. In some instances these measures have failed because of inadequate design considerations. As construction in the area is proceeding apace, more regula­tory control should be imposed on all construction in the area. This is necessary as the demand for more urban housing space continues, more and more of these marginal lands will be utilised.
Throughout the Metropolitan area, the situation remains basically the same, major differences being in level of income of the residents, and conse­quently the size and type of structures.
Where landslides occur along roadways, the debris was cleared so as to allow the easy passage of traffic.
Another site of interest that was visited was in the Eastern Caracas town of Carayaca, site of the new Autopista. The geotechnical problems associated with the construction of four bridges across the Rio Grande River were studied in the field. At the first site the lithology consisted of a dense cover of alluvium and colluvium. The cutting of the slopes for the construction of the bridges and roadways resulted in several problems: (i) Old landslides were reactivated; (ii) New slides were initiated; and (iii) The problem of an existing high water table and erosion of the foot of the slopes by the Rio Grande.
At the second site it was observed how changes in lithology and structure can contribute significantly to slope failure. Foundation and slope failure problems are the major concern in this area. The study demonstrates the useful­ness of geotechnical study in high­lighting existing and potential problems, and also in their solutions.
The Alto Prado/Manzanares area provided a good example of exploding urbanisation. It provides a living example for the study of models and methods that can be used to control and regulate such rapid growth.

The Los Andes Region - One week was spent in the Los Andes Region (western Venezuela), in particular the cities of Merida, Valera, Trujillo and Cristobal, examining first hand, the geotechnical problems and their solutions experienced in this region. Prior to the visit, some time was spent in studying the geology and geography of the different areas. On arrival in Merida, a lecture/discussion was held mainly to give a briefing of the work in progress, problems being encountered and solutions.

Merida - Merida is located in a narrow semi-graben which is fault controlled by one of the major fault systems in Venezuela - the Bocono Fault. Three different series of rocks are exposed in the area:

(i) The thick alluvial deposits with varying thicknesses from 20-120 m in the floor of the graben and can rise to heights of 400 m.

(ii) Pre-Cambrian rocks mainly gneiss and granite, exposed on the eastern side. The rocks are deeply weathered.

(iii) Permian rocks exposed on the western side. These rocks are very fractured and consist of gneiss, granite and schists.

Slopes are steep and constant erosion by the two rivers that drain the area, the Chama and Abarrggas, together with the weathered nature of the rocks, provide ideal conditions for mass movement. The main part of the city is located on the terrace and several houses can be seen perilously close to the edge. Because of the narrow nature of the graben and the increased demand for housing, urbanisation is being forced out to the steeper slopes of the mountains. The increased housing with its associated problems (mainly drainage) have increased the incidents of mass movements on these weathered slopes. Poor construction techniques also contribute to the failure of many houses.

The geotechnique team from the MEM is involved in an extensive geotechnique study to determine which areas are stable and or unstable in an effort to control construction on marginal areas.

In both Valera and Trujillo, the problems encountered are similar to that of Merida, i.e. expanding urbanisation is forcing construction in marginal areas.

San Cristobal The San Cristobal geotechnical study has been completed, and any further development and expansion should use this study as a guideline. The lithology is the main pro­blem in the area. It consists predominantly of clays sands and shales. This causes severe problems for construction, particularly the construction and maintenance of roads.
The geotechnical problems experienced here are similar to the problems encountered in the central and southern parts of Trinidad, i.e. numerous landslides along major roads. The lithology in this part of Trinidad is similar to that in San Cristobal, i.e. clays, sands, silts, hence of all the cities studied in the Los Andes the San Cristobal study is of particular importance to us in Trinidad. It was interesting to observe that here one of the principal methods of dealing with the slides on the highways was simply to clear the material that had been deposited on the pavements. This effectively enabled the roadways to remain open and did not interrupt the free flow of traffic.

CONCLUSION

Most of the cities visited are located in narrow mountain bound valleys, thus their growth is restricted by their locations. Consequently, urban expansion is taking place on the steeper mountainsides, slopes and other marginal areas. In addition, inadequate construction methods are being used, particularly in the lower income areas. Given the existing lithology, structure, state of weathering and the seismic risk of these areas, they will suffer severe physical, economic and social losses in the event of any natural disasters.
Trinidad and Tobago is also facing the problems of rapid urbanization due to population pressures. Marginal areas are also being increasingly used for housing and road construction. This has placed tremendous pressures not only on the natural resources but also on the environment. The incidence of all forms of mass movements has greatly increased, and this will greatly compound problems that may be caused by natural disasters, e.g. flooding and seismic activity.
The studies completed by the MEM are important and very useful. Full use will be made of the techniques and ideas gained from this experience in solving similar problems in Trinidad in our continuing efforts to reduce the effects of natural disasters.

EDITOR'S NOTE: Mrs. Dyer-Williams is a Research Assistant in the Department of Civil Engineering at UWI, St. Augustine. Her four-week training program in Geotechnical Engineering in Venezuela was sponsored by UNESCO and the Ministry of Energy and Mines, Venezuela.

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