The Late Cretaceous Kenerong Leucogranite, a component of the Stong Complex exposed near TNB mini power station, at Renyok waterfall, Jeli, Kelantan consists of a sequence of leucogranite vein and metasedimentary enclaves. Here, varieties of structures developed in both rock types. Structural studies indicate the rocks here had undergone at least four phase of defonnation. It is interpreted that the first defonnation (D 1) with the compression from ESE, which was responsible in the development of foliation and reverse faults was related to the regional stress system during the Late Cretaceous time. The second and third defonnation (D 2 and D 3) with the compression from NE sector, that was related to the fonnation of lateral faults system, pinch-and-swell, boudinage, drag folds and small-scale kink folds might be related to the stress system that were generated by the emplacement of the younger granite in the vicinity. The fourth defonnation (D 4), which was responsible for the nonnal faulting by the reactivation of the preexisting faults, was probably related to the relaxation period after the granite intrusion of the area. Abstrak: Leukogranit Kenerong yang berusia Kapur Lewat, satu komponen daripada Kompleks Stong yang tersingkap berhampiran stesen kuasa mini TNB di Air Terjun Sungai Renyok, Jeli Kelantan terdiri daripada satu turutan telerang leukogranit dan metasidimen. Di sini terdapat kepelbagaian structure telah terbentuk dalam kedua-dua jenis batuan, Kajian struktur menunjukkan batuan telah mengalami sekurang-kurangnya empat fasa canggan. Ditafsirkan bahawa canggaan pertama (D 1) dengan arah mampatan dari UTL yang bertanggung jawab dalam pembentukan foliasi dan sesar songsang adalah berkaitan dengan system tegasan rantau semasa Kapur Lewat. Canggaan kedua dan ketiga (D 2 dan D 3) dengan mampatan daripada sector timur laut (TL) yang berkaitan dengan pembentukan system sesar mendatar, rampingdan-ampul, boudinag, lipatan seret dan lipatan kercau berskala kecil boleh dikaitkan dengan system tegasan yang diakibatkan oleh penempatan granit yang lebih muda di kawasan berhampiran. Canggan ke-empat (D 4) yang bertanggung jawab dalam pembentukan sesar nonnal secara pengaktifan semula satah sesar yang sudah sedia ada mungkin berkaitan dengan tempoh pelepasan selepas rejahan granit di kawasan ini.

Gunungsewu is a karst terrain that shows unique geomorphologic phenomena. The area is mainly composed of limestone of Wonosari Formation. Interaction of tectonic, erosion, denudation, and deposition occurred since Miocene period brings about diversity of landforms that supporting the development of this area as a natural laboratory, specific interest, scientific and educational tourisms. In general the geomorphology of Gunungsewu can be classified into two groups of landforms, the first is positive relief and the second is negative relief. The positive relief includes hills of conical, dome, convex-cone, convex and ridge. The negative relief involves cave, shaft, doline, uvala, locva and polje. This diversity is influenced by variation of physical properties of rock composing the landforms, such as hardness, internal friction angle, and geologic structures including thickness and position of bedding plane as well as joint pattern.

The Java Island is an active volcanic arc that experiences several volcanism episodes, which gradually changes from South to North from the Late Oligocene to Pleistocene, following the subduction of the Australian plates underneath the Eurasian plates. During the Eocene, the southern and northern part of Java was connected as one passive margin system with the sediment supply mainly comes from Sundaland in the north.  The compressional tectonics creates a flexural margin and a deep depression in the central axis of Java Island and acts as an ultimate deep-sea depocenter in the Neogene period. In contrast to the neighboring Northwest and Northeast Java Basins in the Northern edges of Java Island, the basin configuration in the East-West trending depression in median ranges of Java (from Bogor to Kendeng Troughs) are visually undetected by seismic due to the immense Quaternary volcanic eruption covers.Five focused window areas are selected for this study. A total of 1,893 Km sections, 584 rock samples, 1569 gravity and magnetic data, and 29 geochemical samples (rocks, oil, and gas samples) were acquired during the study. Geological fieldwork was focused on the stratigraphic unit composition and the observable features of deformation products from the outcrops. Due to the Paleogene deposit exposure scarcity in the Central-East Java area, the rock samples were also collected from the mud volcano ejected materials in the Sangiran Dome.The distinct subsurface configuration differences between Bogor and Kendeng Troughs are mainly in the tectonic basement involvement and the effect of the shortening on the formerly rift basin. Both Bogor and Kendeng Troughs are active petroleum systems that generate type II /III Kerogen typical of reduction zone organic material derived from transition to the shallow marine environment. The result suggests that these basins are secular from the neighboring basins with a native petroleum system specific to the palaeogeographical condition during the Paleogene to Neogene periods where the North Java systems (e.g., Northwest and Northeast Java Basin) was characterized by oxidized terrigenous type III Kerogen.

Along the boundary of the Western and the Central Belts of Peninsular Malaysia. there are a number of relatively small bodies of serpentinite outcrops. It is believed that these outcrops represent the serpentinised ultramafic rocks, which intruded the Lower Devonian rock fonnations. The serpentinite outcrop at Bukit Rokan Barat, Negeri Sembilan can be considered as one of the best that can be found in this area. The structure observed at this outcrop could represent the structure of the other serpentinite bodies situated along this boundary. Furthennore the deformation history, which is deduced from this structural study, may be used to describe the deformation history that took place along the boundary between the Western and Central Zones of Peninsular Malaysia. The observed serpentinite body at Bukit Rokan Barat is well foliated, trending approximately in north-northwest and northwest direction and moderately to steeply dipping towards northeast. This rock body had suffered at least three phases of shearing, the earlier two (D\ and D 2), were related to ductile, while the third (D 3) was related to brittle deformation. The ductile deformations are indicated by the presence of shear zones, foliations and crenulations folds (microfolds) and lenticular-shaped structures, and the brittle defonnation by the lateral faults. The maximum principal paleo-stresses (sl) related to the ductile defonnations (0\ and D 2) were acting from NE and ENE directions respectively and the brittle deformation (D 3) from NNE direction. The approximately EW tension cracks developed within the lenticular shaped structures are interpreted as the last phase of defonnation suffered by this rock body. Abstrak: Di sepanjang sempadan antara Jalur Barat dan Tengah Semenanjung Malaysia. terdapat beberapa singkapan jasad-jasad kecil serpentinit. Singkapan-singkapan tersebut dipercayai mewakili batuan ultramafik yang telah berubah menjadi serpentinit, yang dahulunya merejah fonnasi batuan Devon Bawah. Salah satu singkapan yang terbaik didapati di Bukit Rokan Barat, Negeri Sembilan. Struktur yang dicerap di singkapan ini boleh mewakili struktur untuk jasadjasad serpentinit lain yang terletak di sepanjang sempadan tersebut. Seterusnya sejarah canggaan yang ditafsirkan berdasar kepada kajian struktur di sini juga boleh digunakan untuk menjelaskan sejarah canggaan yang telah berl;aku di sepanjang sempadan zon Barat dan Tengah Semenanjung Malaysia. Jasad serpentinit yang dicerap di Bukit Rokan Barat mempunyai foliasi yang sangat baik, berarah hampir utarabratlaut hingga baratlaut. Jasad batuan ini mengalami sekurang-kurangnya tiga fasa ricihan, dua yang awal (0\ dan D 2) berkaitan dengan canggaan mulur, manakala yang ketiga (03) berkaitan dengan canggaan rapuh. Canggaan rapuh ditunjukkan oleh kedapatan zon ricih, foliasi, lipatan kerdut dan struktur berbentuk lentikular, manakala canggaan rapuh oleh sesar mendatar. Tegasan kuno utama maksimum (sl) yang berkaitan dengan canggan mulur (0\) dan (02) masingmasing telah bertindak dari arah timurlaut dan ti...

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