This thesis has no abstract.
Table of Contents:
List of tables x
List of figures xii
I. Introduction and previous work 1
II. Geological setting and the petrography of the igneous and metamorphic rocks from southwestern Puerto Rico 6
A. Methods of petrographic analysis 10
B. Bermeja complex 13
1. Schistose amphibolite and massive meta-basaltic dike 15
a. Petrography of the schistose amphibolite 17
b. Petrography of the massive metabasaltic dike 19
2. Serpentinite 22
3. Spilite 25
4. Amphibolitized dolerite 28
5. Mariquita chert 29
6. Cajul volcanic rocks 30
7. Maguayo porphyry 32
C. Rio Loco Formation 34
D. Mayaguez Group. 35
1. Yauco Mudstones 36
2. Maricao Basalt 38
3. Sanbana Grande Andesitey 41
E. San German Formation. 43
III. Metamorphism in southwestern Puerto Rico and relations to the Eastern Greater Antilles 46
A. Metamorphism in the Bermeja complex 47
l. Schistose amphibolite and massive meta-basaltic dike 47
a. Regional metamorphism 48
b. Contact metamorphism 50
2. Amphibolitized dolerite 51
3. Spilite 52
4. Cajul volcanics and Maguayo porphyry 53
B. Metamorphism of the Post-Albian rocks in western Puerto Rico 54
1. Secondary alteration 55
a. Plagioclase alteration 55
b. Olivine alteration 56
c. Pyroxene alteration 57
d. Amphibole alteration 57
e. Alteration of groundmass 58
f. Alteration of the matrix material in the pyroclastic rocks 58
g. Secondary filling of the amygdules and veins 59
2. Regional distribution and metamorphic facies 59
3. Low-grade metamorphism in other parts of the Eastern Greater Antilles 65
4. Comparison with other low-grade metamorphic terranes and their paragenetic relations 69
IV. Geochemistry of the Bermeja complex 84
A. Analytical methods 84
1. Sample selection 84
2. Sample preparation 86
3. Atomic absorption spectrometry 87
4. X-ray spectrometry 90
B. Experimental results 96
1. Atomic absorption spectrometry . 96
2. X-ray spectrometry 108
3. Discussion 115
C. Geochemistry of the major elements 116
1. Schistose amphibolite 117
2. Massive metabasaltic dike 129
3. Spilite and amphibolitized dolerite 141
4. Discussion of the major element chemistry of the basaltic rocks 149
5. Serpentinite 153
D. Geochemistry of trace elements 162
1. Distribution of trace element in the basaltic rocks from the Bermeja complex 162
2. Discussion of the significances of Cr and Ni distribution in the basaltic rocks from the Bermeja complex 166
3. Discussion on the application of the trace element distribution on the petrogenesis of the Bermeja complex 172
V. Secular compositional changes of the volcanic rocks in Puerto Rico and other islands in eastern West Indies and the significances of the Bermeja complex 179
A. Compositional variation of the island arc volcanic rocks . 180
B. The characteristics of tholeiitic, calc-alkalic, and alkalic series 182
C. Stratigraphy and composition of the volcanic rocks of the age from Pre-Middle Cretaceous to Late Tertiary in Puerto Rico and other island in eastern West Indies 203
D. The possible role of the Bermeja complex played in the island arc evolution 197
E. Compositional variation of the volcanic rocks in Puerto Rico and other island in eastern West Indies 203
1. Proportion of tholeiitic and calc-alkalic series rocks 205
2. Frequency distribution of Si02 contents 212
3. Frequency distribution of Fe0*/MgO ratios 215
F. Comparison with other similar island arc system 218
Appendix A-E: Petrographic data of the analyzed samples of the Bermeja complex 222
References cited 231
 

Lee, V.J.B., 1974. Petrography, Metamorphism, and Geochemistry of the Bermeja Complex and Related Rocks in Southwestern Puerto Rico and their Significance in the Evolution of the Eastern Greater Antillian Island Arc. Unpublished MSc. thesis, State University of New York at Albany. 244pp., +xv
University at Albany Science Library call number:  SCIENCE Oversize (*) QE 225 L44X

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