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The Malaysian granitoids form the backbone of the Malay Peninsula and have long been recognized as composed of two distinct granitic provinces separated by the Bentong-Raub suture zone: <table><ol><li>Early Permian to Late Triassic Eastern Province (Indochina – East Malaya) with mainly “I-type” hornblende-bearing granitoids, associated with Cu-Au deposits, and subordinate hornblende-free pluton roof-zones hosting limited Sn-W deposits; and</li> <li>Late Triassic Main Range Province, western Malaysia (Sibumasu) with mainly “S-type” hornblende-free granitoids, associated with Sn-W deposits, and subordinate hornblende-bearing granitoids.</li></ol></table> Field observations and new geochemical data suggested that the division of the Eastern Province and Main Range granitoids using Chappell and White’s (1974) I-S classification could be problematic, as there is a large degree of overlap between the two granitic provinces in terms of lithology, mineralogy and metallogenic affinity. The Main Range granitoids are more fractionated than the hornblende-bearing Eastern Province. Although the two granitic provinces were emplaced into different continental terranes, both granitic provinces exhibit common trace element geochemistry in the enrichment of high field strength elements (HFSE) and rare earth elements (REE) compared to typical Cordilleran I-S granites. Such enrichment is interpreted as an inheritance signature from the protoliths. The Kontum massif (an analogue of Indochina lower continental crust) comprises intraplate ortho-amphibolites and para-gneisses, which could serve as two hypothetical source end-members for the Malaysian granitoids. The model suggests that the geneses of the parental magmas of the Eastern Province and the Main Range Province were related to hybridization of melts derived from protoliths, geochemically and isotopically similar to these two source end-members, but in differing proportions. The fact that the granites from the two granitic provinces are so similar compositionally and metallogenically, suggests that similar protoliths were involved in their source. The incorporation of sedimentary-sourced melt makes the Main Range granitoids transitional I/S-type in nature, but this is unlikely to be true for the less evolved Eastern Province fractionated I-type granitoids. The hybridization of igneous- and sedimentary-sourced melts, and granite fractionation promotes Sn metallogenesis in the Main Range granitic province. Previous ages were obtained using whole rock Rb-Sr and biotite K-Ar geochronology in the 1970s and 1980s, dating methods that almost certainly do not accurately represent the crystallization age of granites. New ion microprobe U-Pb zircon ages are presented that provide new temporal constraints for the Malaysian granitic magmatism. Eastern Province granitoids have U-Pb zircon ages that range from 289 to 220 Ma, while Main Range Province magmatism is constrained between 227 and 201 Ma. A progressive westward younging trend is apparent across the Eastern Province, but becomes less obvious in the Main Range Province. In addition, the U-Pb zircon analysis of the Malaysian granitoids suggests that both granitic provinces have Cambro-Ordovician and Mesoproterozoic inheritance signatures, which match the ages of the Kontum intraplate ortho-amphibolites and para-gneisses, the two source end-members of the suspected Indochina basement. Two different tectonic models have been suggested to explain the formation and the emplacement of the Malaysian granitoids. Both models involve an east-dipping subduction zone during the Early and Mid-Triassic with Palaeo-Tethys lithosphere rolling back along the Bentong-Raub suture zone to produce westward younging ages in the Eastern Province granitoids. The first model (modified after Searle et al. 2012) suggests the younger Main Range granitoids were produced by another Late Triassic – Cretaceous east-dipping (Neo-Tethyan) subduction to the west of Sibumasu, after the Sibumasu – East Malaya collision. The transitional I/S-type geochemistry of the Main Range granitoids was caused by the partial melting of the more heterogeneous Sibumasu basement. The second model (Oliver et al. 2014) suggests the younger Main Range granitoids were produced by the westward underthrusting of Indochina crust of East Malaya beneath Sibumasu along the Bentong-Raub suture zone after the continental collision. In this model, the source of the Main Range granitoids was the pre-collision I-type Eastern Province granitoids. The second model is less likely, as no geological evidence for such underthrust is found in the Malay Peninsula.

En tant que laboratoire naturel, les énormes quantités de granites mésozoïques du sud de la Chine fournissent une occasion unique de comprendre la formation et l'évolution de la croûte mésozoïque et de guider les efforts d'exploration minière dans cette région. Quelles sont les conditions de mise en place de ces granites mésozoïques en Chine du Sud ? Quelle est la relation entre les conditions de mise en place et la minéralisation associée à ces granites mésozoïques?Nous avons établi expérimentalement les relations de phase du granite Jurassique de Qitianling en Chine du Sud. Trois échantillons représentatifs de granites métalumineux contenant des amphiboles ont été choisis pour définir les conditions de cristallisation de ce pluton. Des expériences de cristallisation ont été réalisées à 100-700 MPa, mais principalement à 200 MPa ou 300 MPa, à une fO₂ de ~ NNO-1,3 (1,3 log sous le tampon Ni-NiO) ou ~ NNO + 2,4, à 660 ° C à 900 ° C, et à des teneurs variables en eau (~ 3-8% en poids). Le champ de stabilité des amphiboles et les données de barométrie montrent tous deux que la pression de mise en place du magma se situait autour de 300-350 MPa. Les rapports Fe / Mg amphiboles et biotites suggèrent en outre que la fO₂ magmatique se situait autour de NNO-1 ± 0,5 près du solidus, alors que les oxydes de Fe-Ti enregistrent une augmentation de fO₂ jusqu’à NNO + 1 en conditions sub-solidus. La cristallisation de l'amphibole est limitée aux conditions proches de la saturation en H₂O, nécessitant au moins 5,5% en poids de H₂O dissout à 200 MPa, ou 6 à 8% en poids à> 300 MPa. La présence d'amphibole dans des magmas siliceux métalumineux riches en K₂O indique donc des teneurs en eau significativement supérieures à la valeur canonique de 4% en poids. Les compositions de liquides expérimentaux obtenus à 200-300 MPa reproduisent la tendance géochimique définie par le pluton, ce qui suggère qu'une différenciation dans le réservoir de la croûte supérieure a pu se produire. L'ensemble de ces résultats indique que la fugacité relativement faible en oxygène, la température élevée du magma lors de sa mise en place et sa richesse en eau constituent un environnement favorable à la concentration d'éléments minéralisés au stade magmatique précoce. / As a natural laboratory, the huge amounts of Mesozoic granite distributing in South China provided a unique opportunity to unravel the Mesozoic crust formation and evolution in southern China as well as for guiding mining exploration efforts in this area. What are the emplacement conditions of those Mesozoic granite in South China? What are the relationship between the emplacement conditions and the mineralization among those Mesozoic granites?We have experimentally established the phase relationships for the tin-bearing Jurassic Qitianling granite in South China. Three representative amphibole-bearing, metaluminous granitic samples were chosen for constraining crystallization conditions of the Qitianling pluton. Crystallization experiments were performed at 100-700 MPa, albeit mainly at 200 MPa or 300 MPa, at an fO₂ of ~NNO-1.3 (1.3 log unit below the Ni-NiO buffer) or ~NNO+2.4, at 660°C to 900°C, and at variable melt water contents (~3-8 wt%). Amphibole stability field and barometry both show that the pressure of magma emplacement was around 300-350 MPa. Amphibole and biotite Fe/Mg ratios further suggest that magmatic fO₂ was around NNO-1±0.5 near solidus, while Fe-Ti oxides record an fO2 increase up to NNO+1 below solidus. Amphibole crystallization is restricted to near H₂O-saturation conditions, requiring at least 5.5 wt% H₂Omelt at 200 MPa, or 6-8 wt % at ≥ 300 MPa. Amphibole occurrence in K₂O-rich metaluminous silicic magmas thus indicates water contents significantly higher than the canonical value of 4 wt%. The experimental liquid line of descent obtained at 200-300 MPa mimic the geochemical trend expressed by the pluton suggesting that fractionation in the upper crustal reservoir could happen. We deduced that the relatively low oxygen fugacity, high liquidus temperature and melt water rich condition may be an enabling environment for concentrating the ore elements in the early magmatic stage

O Leucogranito Inhandjara é um pequeno e diferenciado stock Ediacarano (~570 M.a.) que constitui a borda nordeste do Batólito de Itu (estado de São Paulo, SE Brasil), um corpo rapakivi tipo A, composto principalmente por quatro intrusões (Indaiatuba, Salto, Itupeva e Cabreúva). O stock aflora como granitos hololeucocráticos, com teores radiométricos diferenciados (mais enriquecidos em Th e U do que as unidades vizinhas). Ele apresenta as maiores altitudes da região, sendo separado das outras unidades graníticas por um cinturão de gnaisses do embasamento. É constituído por dois litotipos: (1) monzogranito inequigranular a porfirítico com biotita, apresenta megacristais de feldspato potássico em uma matriz de granulação média a grossa; e (2) álcali-feldspato granito equigranular médio a fino, definido como a fácies mais evoluída, consistindo de albita subédrica (An<5) e quartzo, feldspato potássio e Li-siderofilita anédricos. Como fases magmáticas acessórias, apresenta fluorita, topázio, zircão, ilmenita e columbita-tantalita. O Leucogranito é metaluminoso do tipo A (subtipo A2), com caráter alcali-cálcico a alcalino, da série ferroana. Ele apresenta natureza reduzida, sendo classificado como da série ilmenita. As fácies apresentam enriquecimento progressivo em SiO2, Al2O3, Na2O, F, Cs, Rb, Nb, Ta e Y, enquanto os teores de TiO2, Fe2O3, MgO, CaO, Sr, Ba e Zr tendem a diminuir em direção ao Topázio Granito. Para os elementos terras raras (ETR), a fácies evoluída apresenta ligeiro enriquecimento nos elementos pesados, com conteúdo ETRTOTAL em torno de 150 ppm e razão (La/Yb)N de 0,6. Apresenta um padrão quase retilíneo quando normalizada por condrito, com forte anomalia negativa de Eu (Eu/Eu* = 0,003), se destacando das demais unidades do Batólito Itu. Análises químicas de zircão corroboram diretamente com o modelo de diferenciação, apresentando composição enriquecida em Hf, Y, Nb, Th e U nas bordas de cristais no Biotita Granito e por todos cristais do Topázio Granito, o que pode indicar cristalização tardia em presença de fase fluida. O stock apresenta evidências de intenso metassomatismo, principalmente albitização pervasiva e greisenização fissural, onde a paragênese de muscovita com Li, quartzo e clorita (± fluorita) ocorre associada a sulfetos disseminados (pirita, esfalerita e galena, ± calcopirita e molibdenita). O processo de alteração também afetou as rochas gnáissicas encaixantes, transformando-as em corpos de topázio-Li micas-quartzo greisen, associados a veios de quartzo-topázio mineralizados com hübnerita (wolframita rica em Mn) e cassiterita. Portanto, o Leucogranito de Inhandjara apresenta evidências mineralógicas e químicas de forte diferenciação, resultante da cristalização de um magma tardio, enriquecido em fases voláteis e elementos incompatíveis e acentuada pela interação com fluidos hidrotermais ricos em F exsolvidos do magma. Essas características colocam o stock no espectro mais evoluído dentro do Batólito Itu, relacionando-o com os processos de mineralização em metais raros (Nb-Ta-W-Sn) presentes na área da antiga Mina de Inhandjara. / The Inhandjara Leucogranite is a small and differentiated Ediacaran stock (ca 570 Ma) that constitutes the northeaster border of the Itu Batholith (São Paulo state, SE Brazil), an A-type rapakivi body, composed of four main intrusions (Indaiatuba, Salto, Itupeva and Cabreúva). The stock outcrops as hololeucocratic granites, with distinguished radiometric contents (more enriched in Th and U than the surrounding units). It presents the highest altitudes of the region, occurring separated from the other granitic plutons by a belt of basement gneisses. It is made of two main units: (1) inequigranular to porphyritic biotite-bearing monzogranite, with potassium feldspar megacrysts in a medium to coarse-grained matrix; and (2) medium to fine-grained equigranular alkali feldspar granite, defined as the most evolved facies, consisted of subhedral albite and anhedral quartz, potassium feldspar and Li-bearing siderophyllite. As accessory magmatic phases, it shows fluorite, topaz, zircon, ilmenite and columbite-tantalite. The Leucogranite is metaluminous of A-type (A2 subtype), with alkali-calcic to alkalic character, from the ferroan series. It presents reduced nature and is classified into the ilmenite series. The facies show progressive increase of SiO2, Al2O3, Na2O, F, Cs, Rb, Nb, Ta e Y, while contents of TiO2, Fe2O3, MgO, CaO, Sr, Ba e Zr tend to decrease to the alkali-feldspar granite. For the rare earth elements (REE), the evolved facies shows slight enrichment in the heavy elements, with REETOTAL content around 150 ppm and (La/Yb)N ratio of 0.6. It displays an almost flat pattern in chondrite-normalized plots, with strong negative Eu anomaly (Eu/Eu* = 0.003), highlighting itself from the other units from the Itu Batholith. Zircon chemical analyses directly corroborate to the differentiation model, presenting composition enriched in Hf, Y, Nb, Th and U at the crystal borders in biotite granite and throughout the crystals of the alkali-feldspar granite, what may indicate late crystallization in the presence of fluid phase. The stock shows evidences of intensive metasomatism, mainly as pervasive albitisation and fissure to pervasive greisenisation, where the paragenesis of Li-bearing muscovite, quartz and chlorite (± fluorite) occurs associated with disseminate sulphides (pyrite, sphalerite and galena, ± chalcopyrite and molybdenite). The alteration process also affected the gneissic country rocks, transforming them to topaz-Li-bearing micas-quartz greisen bodies, associated with quartz-topaz veins mineralised with hübnerite (Mn-rich wolframite) and cassiterite. Therefore, the Inhandjara Leucogranite presents mineralogical and chemical evidences of strong differentiation, resulting from the crystallization of a late magma, enriched in volatile phases and incompatible elements, and enhanced by interaction with exsolved F-rich hydrothermal fluids. Those characteristics place the stock in the most evolved spectrum inside the Itu Batholith, relating it with the rare-metal (Nb-Ta-W-Sn) mineralization processes which occur in the area from the old Inhandjara Mine.

O Leucogranito Inhandjara é um pequeno e diferenciado stock Ediacarano (~570 M.a.) que constitui a borda nordeste do Batólito de Itu (estado de São Paulo, SE Brasil), um corpo rapakivi tipo A, composto principalmente por quatro intrusões (Indaiatuba, Salto, Itupeva e Cabreúva). O stock aflora como granitos hololeucocráticos, com teores radiométricos diferenciados (mais enriquecidos em Th e U do que as unidades vizinhas). Ele apresenta as maiores altitudes da região, sendo separado das outras unidades graníticas por um cinturão de gnaisses do embasamento. É constituído por dois litotipos: (1) monzogranito inequigranular a porfirítico com biotita, apresenta megacristais de feldspato potássico em uma matriz de granulação média a grossa; e (2) álcali-feldspato granito equigranular médio a fino, definido como a fácies mais evoluída, consistindo de albita subédrica (An<5) e quartzo, feldspato potássio e Li-siderofilita anédricos. Como fases magmáticas acessórias, apresenta fluorita, topázio, zircão, ilmenita e columbita-tantalita. O Leucogranito é metaluminoso do tipo A (subtipo A2), com caráter alcali-cálcico a alcalino, da série ferroana. Ele apresenta natureza reduzida, sendo classificado como da série ilmenita. As fácies apresentam enriquecimento progressivo em SiO2, Al2O3, Na2O, F, Cs, Rb, Nb, Ta e Y, enquanto os teores de TiO2, Fe2O3, MgO, CaO, Sr, Ba e Zr tendem a diminuir em direção ao Topázio Granito. Para os elementos terras raras (ETR), a fácies evoluída apresenta ligeiro enriquecimento nos elementos pesados, com conteúdo ETRTOTAL em torno de 150 ppm e razão (La/Yb)N de 0,6. Apresenta um padrão quase retilíneo quando normalizada por condrito, com forte anomalia negativa de Eu (Eu/Eu* = 0,003), se destacando das demais unidades do Batólito Itu. Análises químicas de zircão corroboram diretamente com o modelo de diferenciação, apresentando composição enriquecida em Hf, Y, Nb, Th e U nas bordas de cristais no Biotita Granito e por todos cristais do Topázio Granito, o que pode indicar cristalização tardia em presença de fase fluida. O stock apresenta evidências de intenso metassomatismo, principalmente albitização pervasiva e greisenização fissural, onde a paragênese de muscovita com Li, quartzo e clorita (± fluorita) ocorre associada a sulfetos disseminados (pirita, esfalerita e galena, ± calcopirita e molibdenita). O processo de alteração também afetou as rochas gnáissicas encaixantes, transformando-as em corpos de topázio-Li micas-quartzo greisen, associados a veios de quartzo-topázio mineralizados com hübnerita (wolframita rica em Mn) e cassiterita. Portanto, o Leucogranito de Inhandjara apresenta evidências mineralógicas e químicas de forte diferenciação, resultante da cristalização de um magma tardio, enriquecido em fases voláteis e elementos incompatíveis e acentuada pela interação com fluidos hidrotermais ricos em F exsolvidos do magma. Essas características colocam o stock no espectro mais evoluído dentro do Batólito Itu, relacionando-o com os processos de mineralização em metais raros (Nb-Ta-W-Sn) presentes na área da antiga Mina de Inhandjara. / The Inhandjara Leucogranite is a small and differentiated Ediacaran stock (ca 570 Ma) that constitutes the northeaster border of the Itu Batholith (São Paulo state, SE Brazil), an A-type rapakivi body, composed of four main intrusions (Indaiatuba, Salto, Itupeva and Cabreúva). The stock outcrops as hololeucocratic granites, with distinguished radiometric contents (more enriched in Th and U than the surrounding units). It presents the highest altitudes of the region, occurring separated from the other granitic plutons by a belt of basement gneisses. It is made of two main units: (1) inequigranular to porphyritic biotite-bearing monzogranite, with potassium feldspar megacrysts in a medium to coarse-grained matrix; and (2) medium to fine-grained equigranular alkali feldspar granite, defined as the most evolved facies, consisted of subhedral albite and anhedral quartz, potassium feldspar and Li-bearing siderophyllite. As accessory magmatic phases, it shows fluorite, topaz, zircon, ilmenite and columbite-tantalite. The Leucogranite is metaluminous of A-type (A2 subtype), with alkali-calcic to alkalic character, from the ferroan series. It presents reduced nature and is classified into the ilmenite series. The facies show progressive increase of SiO2, Al2O3, Na2O, F, Cs, Rb, Nb, Ta e Y, while contents of TiO2, Fe2O3, MgO, CaO, Sr, Ba e Zr tend to decrease to the alkali-feldspar granite. For the rare earth elements (REE), the evolved facies shows slight enrichment in the heavy elements, with REETOTAL content around 150 ppm and (La/Yb)N ratio of 0.6. It displays an almost flat pattern in chondrite-normalized plots, with strong negative Eu anomaly (Eu/Eu* = 0.003), highlighting itself from the other units from the Itu Batholith. Zircon chemical analyses directly corroborate to the differentiation model, presenting composition enriched in Hf, Y, Nb, Th and U at the crystal borders in biotite granite and throughout the crystals of the alkali-feldspar granite, what may indicate late crystallization in the presence of fluid phase. The stock shows evidences of intensive metasomatism, mainly as pervasive albitisation and fissure to pervasive greisenisation, where the paragenesis of Li-bearing muscovite, quartz and chlorite (± fluorite) occurs associated with disseminate sulphides (pyrite, sphalerite and galena, ± chalcopyrite and molybdenite). The alteration process also affected the gneissic country rocks, transforming them to topaz-Li-bearing micas-quartz greisen bodies, associated with quartz-topaz veins mineralised with hübnerite (Mn-rich wolframite) and cassiterite. Therefore, the Inhandjara Leucogranite presents mineralogical and chemical evidences of strong differentiation, resulting from the crystallization of a late magma, enriched in volatile phases and incompatible elements, and enhanced by interaction with exsolved F-rich hydrothermal fluids. Those characteristics place the stock in the most evolved spectrum inside the Itu Batholith, relating it with the rare-metal (Nb-Ta-W-Sn) mineralization processes which occur in the area from the old Inhandjara Mine.

Les bassins sédimentaires se développent souvent le long des zones internes d'anciennes chaînes orogéniques. Nous considérons dans ce projet la Péninsule Malaise (Marge Ouest de la Sonde) comme un haut crustal séparant deux régions de croûte continentale étirée ; les bassins d'Andaman/Malacca du côté occidental et les bassins thaïlandais/malais à l'est. Plusieurs stades de rifting ont été documentés grâce à une intense exploration géophysique régionale. Cependant, la corrélation entre les bassins riftés en mer et le noyau continental terrestre est mal connue. Dans ce mémoire, nous explorons par la cartographie, de missions de terrain et les données sismiques, comment ces structures réactivent des hétérogénéités mésozoïques crustales préexistantes. Le noyau continental semble être relativement peu déformé après l'orogénèse triasique Indosinienne. L’épais méga-horst crustal est bordé par des zones de cisaillement complexes (zones de failles de Ranong, Klong Marui et du Batholithe du Main Range) initiées au Crétacé Supérieur/Paléogène inférieur lors d’une déformation transpressive d’échelle crustale et plus tard réactivées à la fin du Paléogène. L'extension est localisée sur les bords de cette épine dorsale crustale le long d'une bande où la précédente déformation crétacée supérieure est bien exprimée. À l'ouest, le plateau continental est aminci en trois étapes principales qui correspondent à des blocs basculés d’échelle crustale bordés par de larges failles contre-régionales profondément enracinées (Bassin de Mergui). À l'est, des systèmes de rifts prononcés sont également présents, avec de grands blocs basculés (les bassins western Thai, de Songkhla et de Chumphon) qui pourraient représenter de grands boudins de croûte. Dans le domaine central, l'extension est limitée à de demi-grabens étroits isolés de direction N-S développés sur une croûte continentale épaisse, et contrôlés par failles normales pelliculaires, qui se développent souvent au contact entre les granitoïdes et l’encaissant. Les bords extérieurs des régions affectées par le boudinage crustal délimitent le bassin d'Andaman plus grand et profond à l'ouest et les bassins Malais et de Pattani à l'est. À une échelle régionale, les bassins riftés ressemblent à des structures en-échelon N-S le long de grandes bandes de cisaillement de NW-SE. Le rifting est accommodé par de larges failles normales à faible pendage (LANF : Low Angle Normal Faults) réactivant les morpho-structures de la croûte telles que de larges plis et batholithes mésozoïques. Les bassins profonds d'Andaman, Malais et de Pattani semblent situés sur une croûte à rhéologie plus faible qui pourrait être héritée des blocs continentaux dérivés du Gondwana (Birmanie, Sibumasu, et Indochine). L'ensemble des long bassins étroits au coeur de la région (bassins de Khien SA, de Krabi, et du Malacca) apparaissent avoir souffert de relativement peu d'extension. Ce travail montre que le cœur de l’orogène Crétacé supérieure est faiblement réactivé avec seulement quelques traces d’un étirement précoce par rapport aux bords qui sont sujets à un amincissement crustal en larges blocs basculés. A mesure que la déformation augmente, le rifting migre et se localise vers les zones externes et sa géométrie apparait plus « molle » suggérant un mécanisme influencé par la thermique. La coexistence de ces deux géométries au sein d’un même cycle de rifting fait de la marge Ouest de la sonde un cas d’étude édifiant. / Sedimentary basins often develop above internal zones of former orogenic belts. We hereafter consider the Malay Peninsula (Western Sunda) as a crustal high separating two regions of stretched continental crust; the Andaman/Malacca basins in the western side and the Thai/Malay basins in the east. Several stages of rifting have been documented thanks to extensive geophysical exploration. However, little is known on the correlation between offshore rifted basins and the onshore continental core. In this paper, we explore through mapping and seismic data, how these structures reactivate pre-existing Mesozoic basement heterogeneities. The continental core appears to be relatively undeformed after the Triassic Indosinian orogeny. The thick crustal mega-horst is bounded by complex shear zones (Ranong, Klong Marui and Main Range Batholith Fault Zones) inititiated during the Late Cretaceous/Early Paleogene during a thick-skin transpressional deformation and later reactivated in the Late Paleogene. The extension is localized on the sides of this crustal backbone along a strip where earlier Late Cretaceous deformation is well expressed. To the west, the continental shelf is underlain by three major crustal steps which correspond to wide crustal-scale tilted blocks bounded by deep rooted counter regional normal faults (Mergui Basin). To the east, some pronounced rift systems are also present, with large tilted blocks (Western Thai, Songkhla and Chumphon basins) which may reflect large crustal boudins. In the central domain, the extension is limited to isolated narrow N-S half grabens developed on a thick continental crust, controlled by shallow rooted normal faults, which develop often at the contact between granitoids and the host-rocks. The outer limits of the areas affected by the crustal boudinage mark the boundary toward the large and deeper Andaman basin in the west and the Malay and Pattani basins in the east. At a regional scale, the rifted basins resemble N-S en-echelon structures along large NW-SE shear bands. The rifting is accommodated by large low angle normal faults (LANF) running along crustal morphostructures such as broad folds and Mesozoic batholiths. The deep Andaman, Malay and Pattani basins seem to sit on weaker crust inherited from Gondwana-derived continental blocks (Burma, Sibumasu, and Indochina). The set of narrow elongated basins in the core of the Region (Khien Sa, Krabi, and Malacca basins) suffered from a relatively lesser extension. This work shows that the core of the late Cretaceous Orogeny is weakly reactivated during the subsequent rifting with only few evidences of stretching whereas its sides are thinned with large tilted blocks. The rifting migrates and localizes on the external regions and its geometry appears more ductile suggesting the influence of a thermal activity in the process. The coexistence of both geometries in a single rifting cycle makes the western margin of Sundaland an enlightening example.

Wong Cheuk Yuet. / Thesis submitted in: July 2003. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 223-233). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.i / ABSTRACT --- p.iv / TABLE OF CONTENTS --- p.ix / LIST OF FIGURES --- p.xii / LIST OF PLATES --- p.xiv / LIST OF TABLES --- p.xv / Chapter CHAPTER 1 --- Introduction --- p.1 / Chapter 1.1 --- About the thesis --- p.1 / Chapter 1.2 --- Background of Hong Kong --- p.1 / Chapter 1.2.1 --- Geography --- p.1 / Chapter 1.2.2 --- Climate --- p.3 / Chapter 1.2.3 --- Vegetation and their distribution --- p.7 / Chapter 1.2.4 --- Floristic composition --- p.10 / Chapter 1.2.5 --- Urban development and forestry history --- p.11 / Chapter 1.3 --- Restoration of degraded lands --- p.13 / Chapter 1.3.1 --- Importance of restoration --- p.13 / Chapter 1.3.2 --- Sites for restoration --- p.16 / Chapter 1.3.3 --- Substratum for restoration in Hong Kong --- p.16 / Chapter 1.3.4 --- Revegetation --- p.19 / Chapter 1.4 --- Species for plantation --- p.20 / Chapter 1.4.1 --- Exotics vs. natives --- p.20 / Chapter 1.4.2 --- Fields of controversy --- p.23 / Chapter 1.5 --- Project objectives and significances --- p.26 / Chapter 1.6 --- Study sites --- p.27 / Chapter 1.6.1 --- Criteria for site selection --- p.27 / Chapter 1.6.2 --- Shek O Quarry and Lam Tei Quarry --- p.27 / Chapter 1.6.3 --- Rehabilitation of the quarries --- p.31 / Chapter 1.6.4 --- Site specificity and representativeness --- p.33 / Chapter CHAPTER 2 --- Characterization of CDG on Site --- p.37 / Chapter 2.1 --- Introduction --- p.37 / Chapter 2.2 --- Materials and methods --- p.39 / Chapter 2.2.1 --- Soil sampling --- p.39 / Chapter 2.2.2 --- Soil analysis --- p.40 / Chapter 2.3 --- Statistical analysis --- p.42 / Chapter 2.4 --- Results and discussion --- p.43 / Chapter 2.4.1 --- Characterization and comparison of soil stock between two sites --- p.43 / Chapter 2.4.2 --- Comparison between raw soil and grassed soil --- p.46 / Chapter 2.4.3 --- Comparison among phases --- p.49 / Chapter 2.4.4 --- Comparison with other studies --- p.56 / Chapter 2.4.5 --- Soil development in two quarries --- p.58 / Chapter 2.5 --- Conclusions --- p.59 / Chapter CHAPTER 3 --- Natives Performance in Revegetation on CDG - I. Common PlantationSpecies --- p.61 / Chapter 3.1 --- Introduction --- p.61 / Chapter 3.2 --- Materials and methods --- p.64 / Chapter 3.3 --- Statistical analysis --- p.66 / Chapter 3.4 --- Results and discussion --- p.68 / Chapter 3.4.1 --- Height and basal diameter at the beginning of study --- p.68 / Chapter 3.4.2 --- Relative growth rates of different ages --- p.72 / Chapter 3.4.3 --- Comparison between sites --- p.84 / Chapter 3.5 --- Conclusions --- p.89 / Chapter CHAPTER 4 --- Natives Performance in Revegetation on CDG ´ؤ II. the Neglected Species --- p.91 / Chapter 4.1 --- Introduction --- p.91 / Chapter 4.1.1 --- Seed dispersal and rehabilitation --- p.91 / Chapter 4.1.2 --- Conservation and rehabilitation --- p.92 / Chapter 4.1.3 --- Framework species --- p.93 / Chapter 4.2 --- Materials and Methods --- p.95 / Chapter 4.2.1 --- Species selection --- p.95 / Chapter 4.2.2 --- Planting area --- p.97 / Chapter 4.2.3 --- Planting scheme --- p.97 / Chapter 4.2.4 --- Planting protocol --- p.100 / Chapter 4.2.5 --- Field measurements --- p.102 / Chapter 4.3 --- Statistical analysis --- p.106 / Chapter 4.4 --- Results and discussion --- p.107 / Chapter 4.4.1 --- General performance of the planted species --- p.107 / Chapter 4.4.2 --- General inter-specific comparison --- p.116 / Chapter 4.4.3 --- Effect of aspect on seedling performance --- p.120 / Chapter 4.4.4 --- Effect of elevation on seedling performance --- p.140 / Chapter 4.4.5 --- Overall species evaluation --- p.147 / Chapter 4.5 --- Conclusions --- p.151 / Chapter CHAPTER 5 --- Further Exploration of Other Potential Pioneer Natives --- p.153 / Chapter 5.1 --- Introduction --- p.153 / Chapter 5.2 --- Materials and methods --- p.155 / Chapter 5.3 --- Results and discussion --- p.156 / Chapter 5.3.1 --- Inter-site comparison --- p.161 / Chapter 5.3.2 --- Inter-phase comparison --- p.163 / Chapter 5.3.3 --- Ranking of species --- p.171 / Chapter 5.3.4 --- Invaders for exploration --- p.171 / Chapter 5.4 --- Conclusions --- p.177 / Chapter CHAPTER 6 --- Performance of Five Natives under Different N:P Combinations --- p.180 / Chapter 6.1 --- Introduction --- p.180 / Chapter 6.2 --- Materials and Methods --- p.181 / Chapter 6.3 --- Statistical analysis --- p.185 / Chapter 6.4 --- Results and discussion --- p.186 / Chapter 6.4.1 --- Height --- p.186 / Chapter 6.4.2 --- Basal diameter --- p.193 / Chapter 6.4.3 --- Leaf number --- p.200 / Chapter 6.4.4 --- Total dry weight --- p.200 / Chapter 6.4.5 --- Aerial and underground dry weight --- p.202 / Chapter 6.4.6 --- "Chlorophyll florescence, stomatal conductance and transpiration" --- p.207 / Chapter 6.4.7 --- General species performance in treatments --- p.214 / Chapter 6.4.8 --- Comparison with seedling performance in field trial --- p.215 / Chapter 6.5 --- Conclusions --- p.216 / Chapter CHAPTER 7 --- General Conclusions --- p.217 / REFERENCES --- p.223 / APPENDIX I --- p.234 / APPENDIX II --- p.235 / APPENDIX III --- p.237 / APPENDIX IV --- p.238 / APPENDIX V --- p.241 / APPENDIX VI --- p.242

Thesis (M.S.)--University of Tennessee, Knoxville, 2010. / Title from title page screen (viewed on July 20, 2010). Thesis advisor: Robert D. Hatcher, Jr. Vita. Includes bibliographical references.

O estágio pós-colisional Neoproterozoico no sul do Brasil é marcado por intenso magmatismo granítico controlado por zonas de cisalhamento transcorrentes, relacionadas ao Cinturão de Cisalhamento Sul-brasileiro (CCSb). O CCSb controlou a ascensão e o posicionamento de magmas crustais e mantélicos. Neste contexto, O Granito Corre-mar (GCM) representa uma pequena intrusão posicionado em uma zona de baixa deformação localizada entre dois importantes segmentos do CCSb: as Zonas de Cisalhamento Major Gercino e Itajaí- Perimbó. O GCM possui um diagnóstico par de foliações subevetical que forma um par S-C sinistral, presente em todas as intrusões, independentemente do tamanho, e foi posicionado em um sistema conjugado, onde um cisalhamento sinistral de direção NNE, e uma extensão na direção NW-SE, gerando espaço ao longo da direção NE. Deformação de estado sólido associada ao cisalhamento NNE é atestado por microestruturas como recristalização de feldspatos e caudas de recristalização assimétricas. A abertura é atribuída à dinâmica regional destral transcorrente das zonas de cisalhamento Major Gercino e Itajaí-Perimbó, sendo que o posicionamento foi controlado essencialmente pela componente de estensão NW-SE. A idade de cristalização em zircão U-Pb LAMC- ICP-MS do GCM de 615 ± 4 Ma, muito próxima a outros granitos regionais, como as idades de 611 Ma do Granito Serra dos Macacos (GSM) e de 620 Ma do Granito Rio Pequeno (GRP) sugere que esses três corpos graníticos são sincrônicos. As fortes feições de deformação presents no GCM, diferentemente dos granitos Neoproterozoicos próximos, demonstra que o espaço, mais do que o tempo, pode explicar a diferença dos padrões estruturais identificados no GCM. Assinaturas geoquímicas e de isótopos de Sr-Nd, como caráter levemente peraluminoso, altos conteúdos de K, altas razões de ETRL/ETRP, moderados conteúdos de Rb, Nb, Zr e ETR em relação à SiO2, juntamente com baixas razões de 86Sr/87Sri e valores de εNdt fortemente negativos, indicam que o GCM é derivado de fontes crustais antigas, possivelmente relacionadas à rochas quartzofeldspáticas ortognáissicas Paleoproterozoicas do Complexo Camboriú. A relaçãodas das idades das heranças Arqueanas a Paleoproterozoicas do GCM com as idades dos eventos de migmatização identificados no Complexo Camboriú, além da relação das idades de cristalização de ~615-611 Ma dos granitos crustais da área com o último evento de migmatização em 640-610, reforça a conexão genética entre eles. As idades TDM paleoproterozoicas, as assinaturas geoquímicas e isotópicas, a cristalização e as idades de heranças do GCM e do GSM atestam que eles representam pulsos graníticos contemporâneos e comagmáticos, com uma conexão genética com o evento de migmatização Neoproterozoico do Complexo Camboriú. / The Neoproterozoic post-collisional stage in south Brazil is marked by intense granitic magmatism controlled by transcurrent shear zones all related to the Southern Brazilian Shear Belt (SBSB). The SBSB controls the ascent and emplacement of crustal and mantle magmas. In such scenario, the Corre-mar Granite (CMG), represent a small intrusion emplaced in a low strain zone located between two important segments of the SBSB: the Major Gercino and Itajaí-Perimbó Shear Zones. The CMG have a diagnostic subvertical foliation pair that form a sinistral S-C pair, present in all intrusions regardless of their size, and was emplaced within a conjugate system, where sinistral NNE shearing and NW-SE extension were both active, generating space along the NE direction. Solid state deformation associated to the NNE shearing is attested by microstructures as feldspar recrystallization and asymmetric recrystallization tails. The opening is attributed to the regional dextral transcurrent dynamics of the Major Gercino and Itajaí-Perimbó shear zones and magma emplacement was essentially conditioned by the NW extension component. The zircon U-Pb LA-MC-ICP-MS crystallization age of CMG at 615 ± 4 Ma, very close to other regional granites, as the 611 Ma Serra dos Macacos (SMG) and 620 Ma Rio Pequeno Granite (RPG) points these three granitic bodies as quite synchronous. The strong deformation features present in the CMG, as opposed to the other nearby Neoproterozoic granites (RPG and SMG) demonstrate that space, rather than time, must be called upon to explain the difference in the structural patterns identified in the CMG. Geochemical and Sr-Nd isotopic signatures, as slight peraluminous character, high-K contents, high LREE/HREE ratios, moderate Rb, Nb, Zr, and REE contents to regular SiO2, together with low 86Sr/87Sri and the strongly negative εNdt values indicate that the CMG is derived from old crustal sources possibly related to the Paleoproterozoic Camboriú Complex quartz-feldspatic orto-gneissic rocks. The match of the Archean to Paleoproterozoic inheritance ages of the CMG with the migmatization event ages identified in the Camboriú Complex and moreover the match of the crystallization ages of ~615-611 Ma of the crustalderived granites with the last migmatization event at 640-610 Ma reinforces the genetic link between them. The Paleoproterozoic TDM ages, the geochemical and isotopic signatures, the crystallization and inheritance ages resemblance of the CMG and the SMG attest that they represent comagmatic and contemporaneous granitic pulses with a genetic connection with the Neoproterozoic migmatization event in the Camboriu Complex.

O estágio pós-colisional Neoproterozoico no sul do Brasil é marcado por intenso magmatismo granítico controlado por zonas de cisalhamento transcorrentes, relacionadas ao Cinturão de Cisalhamento Sul-brasileiro (CCSb). O CCSb controlou a ascensão e o posicionamento de magmas crustais e mantélicos. Neste contexto, O Granito Corre-mar (GCM) representa uma pequena intrusão posicionado em uma zona de baixa deformação localizada entre dois importantes segmentos do CCSb: as Zonas de Cisalhamento Major Gercino e Itajaí- Perimbó. O GCM possui um diagnóstico par de foliações subevetical que forma um par S-C sinistral, presente em todas as intrusões, independentemente do tamanho, e foi posicionado em um sistema conjugado, onde um cisalhamento sinistral de direção NNE, e uma extensão na direção NW-SE, gerando espaço ao longo da direção NE. Deformação de estado sólido associada ao cisalhamento NNE é atestado por microestruturas como recristalização de feldspatos e caudas de recristalização assimétricas. A abertura é atribuída à dinâmica regional destral transcorrente das zonas de cisalhamento Major Gercino e Itajaí-Perimbó, sendo que o posicionamento foi controlado essencialmente pela componente de estensão NW-SE. A idade de cristalização em zircão U-Pb LAMC- ICP-MS do GCM de 615 ± 4 Ma, muito próxima a outros granitos regionais, como as idades de 611 Ma do Granito Serra dos Macacos (GSM) e de 620 Ma do Granito Rio Pequeno (GRP) sugere que esses três corpos graníticos são sincrônicos. As fortes feições de deformação presents no GCM, diferentemente dos granitos Neoproterozoicos próximos, demonstra que o espaço, mais do que o tempo, pode explicar a diferença dos padrões estruturais identificados no GCM. Assinaturas geoquímicas e de isótopos de Sr-Nd, como caráter levemente peraluminoso, altos conteúdos de K, altas razões de ETRL/ETRP, moderados conteúdos de Rb, Nb, Zr e ETR em relação à SiO2, juntamente com baixas razões de 86Sr/87Sri e valores de εNdt fortemente negativos, indicam que o GCM é derivado de fontes crustais antigas, possivelmente relacionadas à rochas quartzofeldspáticas ortognáissicas Paleoproterozoicas do Complexo Camboriú. A relaçãodas das idades das heranças Arqueanas a Paleoproterozoicas do GCM com as idades dos eventos de migmatização identificados no Complexo Camboriú, além da relação das idades de cristalização de ~615-611 Ma dos granitos crustais da área com o último evento de migmatização em 640-610, reforça a conexão genética entre eles. As idades TDM paleoproterozoicas, as assinaturas geoquímicas e isotópicas, a cristalização e as idades de heranças do GCM e do GSM atestam que eles representam pulsos graníticos contemporâneos e comagmáticos, com uma conexão genética com o evento de migmatização Neoproterozoico do Complexo Camboriú. / The Neoproterozoic post-collisional stage in south Brazil is marked by intense granitic magmatism controlled by transcurrent shear zones all related to the Southern Brazilian Shear Belt (SBSB). The SBSB controls the ascent and emplacement of crustal and mantle magmas. In such scenario, the Corre-mar Granite (CMG), represent a small intrusion emplaced in a low strain zone located between two important segments of the SBSB: the Major Gercino and Itajaí-Perimbó Shear Zones. The CMG have a diagnostic subvertical foliation pair that form a sinistral S-C pair, present in all intrusions regardless of their size, and was emplaced within a conjugate system, where sinistral NNE shearing and NW-SE extension were both active, generating space along the NE direction. Solid state deformation associated to the NNE shearing is attested by microstructures as feldspar recrystallization and asymmetric recrystallization tails. The opening is attributed to the regional dextral transcurrent dynamics of the Major Gercino and Itajaí-Perimbó shear zones and magma emplacement was essentially conditioned by the NW extension component. The zircon U-Pb LA-MC-ICP-MS crystallization age of CMG at 615 ± 4 Ma, very close to other regional granites, as the 611 Ma Serra dos Macacos (SMG) and 620 Ma Rio Pequeno Granite (RPG) points these three granitic bodies as quite synchronous. The strong deformation features present in the CMG, as opposed to the other nearby Neoproterozoic granites (RPG and SMG) demonstrate that space, rather than time, must be called upon to explain the difference in the structural patterns identified in the CMG. Geochemical and Sr-Nd isotopic signatures, as slight peraluminous character, high-K contents, high LREE/HREE ratios, moderate Rb, Nb, Zr, and REE contents to regular SiO2, together with low 86Sr/87Sri and the strongly negative εNdt values indicate that the CMG is derived from old crustal sources possibly related to the Paleoproterozoic Camboriú Complex quartz-feldspatic orto-gneissic rocks. The match of the Archean to Paleoproterozoic inheritance ages of the CMG with the migmatization event ages identified in the Camboriú Complex and moreover the match of the crystallization ages of ~615-611 Ma of the crustalderived granites with the last migmatization event at 640-610 Ma reinforces the genetic link between them. The Paleoproterozoic TDM ages, the geochemical and isotopic signatures, the crystallization and inheritance ages resemblance of the CMG and the SMG attest that they represent comagmatic and contemporaneous granitic pulses with a genetic connection with the Neoproterozoic migmatization event in the Camboriu Complex.