Phosphate rock on the Netherlands Antilles

Phosphate rock on the Netherlands Antilles

Introduction

In 1991 I published my thesis on

SEDIMENTARY PETROLOGY, ORIGIN AND MINING HISTORY OF THE PHOSPHATE ROCKS OF KLEIN CURACAO, CURACAO AND ARUBA, NETHERLANDS WEST INDIES

This book (ISBN 90-74624-01-4) can be ordered at:

Foundation for Scientific Research in the Caribbean Region
Plantage Middenlaan 45
1018 DC Amsterdam
the Netherlands

It is volume 130 in their Publication series. It costs about NLG 60,-- (about US$ 35). The Publication Series contains many more very interesting titles on the biology, geology, and natural history in general of the (Netherlands) Caribbean islands. A must for Caribean natural scientists, and others interested in this topic!!

As an introduction to this publication I enclose on this page:
- the contents
- an excerpt of the summary in English.

Contents

Chapter 1
Introduction

1.1 Introduction
1.1.1 Origin and aim of the research
1.1.2 Structure of the report
1.2 Research methods
1.2.1 Fieldwork
1.2.2 Topographic maps and aerial photographs
1.2.3 Sampling
1.2.4 Laboratory research


Chapter 2
Setting of the southern Netherlands West Indies

2.1 Geographic setting
2.2 Tectonic setting
2.3 Geological research
2.4 Late Quaternary sea-level fluctuations
2.4.1 Eustatic sea-level fluctuations
2.4.2 Sea-level records on the Antillean islands
2.4.3 Discussion and conclusions
2.5 Hydrographic setting
2.6 Climate
2.6.1 Wind
2.6.2 Temperature
2.6.3 Rainfall
2.6.4 Relative humidity and surface waters
2.7 Soils
2.8 Flora
2.9 Fauna


Chapter 3
Phosphorus-rich rocks - nomenclature, classification, and petrographic terminology

3.1 Phosphorus in the lithosphere
3.2 Basic terminology of phosphorus-rich rocks
3.3 Basic chemistry of phosphate rocks
3.4 Classification of main groups of phosphate rocks
3.4.1 Primary phosphate rocks
3.4.2 Secondary phosphate rocks
3.4.3 Distinction between phosphate rock types
3.5 Principles of phosphorite petrography
3.6 Phosphorite petrography - textural elements
3.6.1 Grain types
3.6.2 Matrix and cement
3.7 Phosphorite classification system


Chapter 4
Phosphorites of Klein Curacao

4.1 Introduction
4.1.1 Geographical and geomorphological setting
4.1.2 Geological setting
4.1.3 Previous research
4.1.4 Field survey and sampling
4.2 General stratigraphy
4.3 Petrology
4.3.1 Bioclastic calcarenites and calcilutites
4.3.2 Moderately to well sorted bioclastic calcarenites
4.3.3 Peloidal calcilutites
4.3.4 Phosphorites
4.4 Mineralogy and geochemistry
4.5 Discussion and conclusions
4.5.1 Origin of the investigated deposits
4.5.2 Origin of the phosphorus


Chapter 5
Pinnacle field phosphorites, Table Mountain, Curacao

5.1 Introduction
5.1.1 Geographical, geological and geomorphological setting
5.1.2 Phosphorite occurrences
5.1.3 Previous research
5.2 General stratigraphy
5.3 Petrology
5.3.1 (Dolomitic) terrace limestones
5.3.2 Dolomite
5.3.3 Crystalline calcite
5.3.4 Calcrete
5.3.5 Oolitic phosarenite
5.3.6 Rubble phosphorite
5.4 Mineralogy and geochemistry
5.5 Discussion and conclusions
5.5.1 Setting of the investigated deposits
5.5.2 Development of the investigated deposits
5.5.3 Origin of the phosphorus


Chapter 6
Phosphatized limestones of Table Mountain Santa Barbara, Curacao

6.1 Introduction
6.1.1 Geological and geomorphological setting
6.1.2 Previous research
6.1.3 Method of processing drilling data
6.2 Stratigraphical setting - characteristics of the Ceru Domi Formation
6.2.1 Petrology of Ceru Domi Formation limestones
6.2.2 Stratification within the Ceru Domi Formation
6.2.3 The basal plane of the Ceru Domi Formation
6.2.4 General chemistry of Ceru Domi limestones
6.2.5 Horizontal extent of the phosphatized zone within the Ceru Domi Formation
6.2.6 Vertical extent of the phosphatized zone within the Ceru Domi Formation
6.2.7 Chemical trends within the phosphatized zone
6.3 Petrology of the phosphatized limestones - lenticular phosphate bodies in the western excavations
6.3.1 Zone 1: non-phosphatic limestones
6.3.2 Zone 2: partly phosphatized limestones
6.3.3 Zone 3: completely phosphatized limestones
6.3.4 Zone 4: laminated phosphate cement ('multipartite phosphate')
6.3.5 Zone 5: central void
6.4 Petrology of the phosphatized limestones - non-lenticular phosphate zones in the eastern excavations
6.5 Mineralogy and geochemistry
6.6 Discussion and conclusions
6.6.1 Spatial differences in degree of diagenesis
6.6.2 Diagenetic sequence
6.6.3 Phosphate source and age of phosphatization


Chapter 7
Phosphorites of south-east Aruba

7.1 Introduction
7.1.1 Geological setting
7.1.2 Geology of south-east Aruba
7.1.3 Previous research
7.2 Stratigraphic setting
7.3 Petrology
7.3.1 Detrital peloidal phosarenites
7.3.2 Ferruginous phosphorites
7.3.3 Calcareous phosphorites
7.3.4 Phosphatic "pebbles"
7.4 Mineralogy and geochemistry
7.5 Discussion and conclusions
7.5.1 Origin of the Aruba phosphorites
7.5.2 Diagenetic events
7.5.3 Phosphate sources
7.5.4 Age estimate


Chapter 8
Geology of the phosphate rocks of Curacao, Klein Curacao and Aruba - summary and conclusions

8.1 Introduction
8.2 Lateral and vertical extent
8.3 Internal organization
8.4 Petrololgy
8.5 Diagenesis
8.5.1 Diagenesis in granular phosphorites
8.5.2 Diagenesis in Table Mountain rock phosphates
8.5.3 Mechanisms of phosphate emplacement
8.5.4 Spatial distribution of diagenesis
8.6 Mineralogy and geochemistry
8.6.1 Mineralogy
8.6.2 Geochemistry
8.6.3 Impact of weathering
8.7 Conclusions


Chapter 9
The economic history of phosphate mining on Klein Curacao, Curacao, Aruba and Bonaire

9.1 Introduction
9.2 Phosphate rocks on Klein Curacao
9.2.1 Introduction
9.2.2 Phosphate mining on Klein Curacao
9.2.3 Value of phosphate mined on Klein Curacao
9.3 Phosphate rocks on Table Mountain, Santa Barbara, Curacao
9.3.1 The first exploitation period (1875-1895)
9.3.2 No operations (1896-1912)
9.3.3 The second exploitation period (1913-present)
9.4 Other phosphate rocks on Curacao
9.5 Phosphate rocks on Aruba
9.5.1 Introduction
9.5.2 Phosphate production - amounts and values
9.5.3 Government phosphate mining revenues
9.6 Phosphate rocks on Bonaire
9.7 Summary


Excerpt of the Abstract


Chapter 1 summarizes the main objective of the study and the research methods applied.

Chapter 2 deals with different aspects of the setting of the investigated islands, the core of which is of volcanic origin, but the rim of which consists of detrital sediments. These sediments record a histry of eratic uplifting. A tentative correlation is presented between specific Pleistocene sea-level maxima and certain coastal terraces.

Chapter 3 presents a basic petrographic terminology for phosphate rocks

The following four chapters describe in detail the petrology and origin of the phosphate rocks of Klein Curacao (Chapter 4), the phosphorites which occur in pinnacle fields on the southern slope of Table Mountain, Curacao ( Chapter 5), the rock phosphates within the main body of Table Mountain, Curacao (Chapter 6) and the phosphorites of south-east Aruba (Chapter 7).

Chapter 8 summarizes and reviews the similarities and differences between the various Antillean phosphate rocks, and presents a synthesis of these features. Several petrographic subunits are recognized, which document successive phases of phosphorite emplacement. The material was derived from different sources, including older phosphate deposits and fresh calcareous, evaporitic and siliciclastic sources. The genetic environment generally was peri-marine, but suffered intense land dominated processes.

Chapter 8 also comments on diagenesis of the phosphate rocks, which includes three successive diagenetic mechanisms of phosphate cementation, limestone dissolution and continued metasomatic phosphatization. Type and degree of phosphatization appears, at least partly, to have been defined by carbonate mineralogy.

Finally, Chapter 9 provides a summary of the history of phosphorite mining on Klein Curacao, Curacao, Aruba and Bonaire. It is concluded that between 1871 and 1985 a total of at least 6 million metric tonnes of guano, phosphorite and other types of phosphate rock were exported with an estimated value of at least 300 million guilders.


c101/updated 2004-12-24