A review of biostratigraphic and lithofacies data is used to show that there is no major unconformity in the stratigraphic record of north Sarawak or southwest Sabah near the end of the Early Miocene (approximately 17-15 Ma). The existence of such an unconformity has been cited in many papers in the past decade and used as a data point in the construction of regional geological hypotheses. Exploration well and outcrop data identifies two major unconformities in SW Sabah (the base and top of Stage III; BMU and DRU; roughly 24 and 13-12 Ma), and in offshore west Sarawak a third unconformity (MMU c. 16 Ma) which fades in effect towards onshore Sarawak. In recent years the names of these distinct unconformities have become conflated as workers had overlooked the origins and definitions of these features. This history is reviewed here in order to clarify future work.
{"title":"Field And Well Evidence For Major Unconformities In North Sarawak, Compared To Southwest Sabah, Malaysia","authors":"P. Lunt","doi":"10.7186/bgsm74202205","DOIUrl":"https://doi.org/10.7186/bgsm74202205","url":null,"abstract":"A review of biostratigraphic and lithofacies data is used to show that there is no major unconformity in the stratigraphic record of north Sarawak or southwest Sabah near the end of the Early Miocene (approximately 17-15 Ma). The existence of such an unconformity has been cited in many papers in the past decade and used as a data point in the construction of regional geological hypotheses. Exploration well and outcrop data identifies two major unconformities in SW Sabah (the base and top of Stage III; BMU and DRU; roughly 24 and 13-12 Ma), and in offshore west Sarawak a third unconformity (MMU c. 16 Ma) which fades in effect towards onshore Sarawak. In recent years the names of these distinct unconformities have become conflated as workers had overlooked the origins and definitions of these features. This history is reviewed here in order to clarify future work.","PeriodicalId":39503,"journal":{"name":"Bulletin of the Geological Society of Malaysia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46230893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Z. Konjing, Abdul Hadi Abd Rahman, M. Ismail, N. Siddiqui
Palynological analysis was conducted on one hundred and twenty-four samples collected from ten sedimentary outcrops in Sangan, Tatau, Bintulu and Similajau areas of central Sarawak. These outcrops form part of the Oligocene-Miocene marginal marine successions of the Nyalau Formation. Rich palynomorph assemblages were recovered from the samples and they provide well-preserved palynological record for the Oligocene-Miocene boundary in the onshore of northwest Borneo. Three distinct palynological zones were identified based on changes in pollen assemblages. The three zones are informally named FT-I, FT-II and FT-III. The FT-I zone is characterized by high frequency of Florschuetzia trilobata with common Florschuetzia semilobata including sporadic Meyeripollis naharkotensis. High percentage of F. trilobata and sporadic occurrence of F. semilobata are typical of the FT-II zone. Another important characteristic for this zone is characterized by common to abundant Casuarina type pollen while M. naharkotensis is virtually absent. The FT-III zone is marked by the presence of Florschuetzia levipoli. The zone is also characterized by abundant F. trilobata including regular occurrence of F. semilobata with common montane elements represented by Pinus, Picea, Alnus, Ephedra and Tsuga. All the identified zones record regular occurrence of Gramineae throughout with strong variation in diversity and frequency of peat swamp taxa represented by Blumeodendron type, Calophyllum type, Stemonurus type Calamus type and Dactylocladus type. The mangrove element such as Rhizophora type exhibits gradual increased in number throughout the FT-I and FT-II zone and showing reduced abundance in FT-III zone. These three zones are correlatable to the Late Oligocene to Early Miocene palynostratigraphy of the Cycle I and Cycle II in the Sarawak Basin. The palynological successions from these areas suggest a typical wet climate with intermittent seasonally dry conditions throughout the Late Oligocene - Early Miocene. This is evident from the regular occurrence of grass pollen i.e., Gramineae/Poaceae with common rain forest and peatswamp elements. This is supported by the common to high frequency of mangrove pollen notably Rhizophora type (Zonocostites ramonae). The Early Miocene may have experienced occasional super wet climatic conditions where rain forest pollen assemblages were prevalent including intermittent acme of Casuarina type pollen.
{"title":"Late Oligocene-Early Miocene Palynological Succession From Marginal Marine Deposits, Nyalau Formation, Bintulu Sarawak: Palynostratigraphy, Paleovegetation And Paleoclimate Significance","authors":"Z. Konjing, Abdul Hadi Abd Rahman, M. Ismail, N. Siddiqui","doi":"10.7186/bgsm74202202","DOIUrl":"https://doi.org/10.7186/bgsm74202202","url":null,"abstract":"Palynological analysis was conducted on one hundred and twenty-four samples collected from ten sedimentary outcrops in Sangan, Tatau, Bintulu and Similajau areas of central Sarawak. These outcrops form part of the Oligocene-Miocene marginal marine successions of the Nyalau Formation. Rich palynomorph assemblages were recovered from the samples and they provide well-preserved palynological record for the Oligocene-Miocene boundary in the onshore of northwest Borneo. Three distinct palynological zones were identified based on changes in pollen assemblages. The three zones are informally named FT-I, FT-II and FT-III. The FT-I zone is characterized by high frequency of Florschuetzia trilobata with common Florschuetzia semilobata including sporadic Meyeripollis naharkotensis. High percentage of F. trilobata and sporadic occurrence of F. semilobata are typical of the FT-II zone. Another important characteristic for this zone is characterized by common to abundant Casuarina type pollen while M. naharkotensis is virtually absent. The FT-III zone is marked by the presence of Florschuetzia levipoli. The zone is also characterized by abundant F. trilobata including regular occurrence of F. semilobata with common montane elements represented by Pinus, Picea, Alnus, Ephedra and Tsuga. All the identified zones record regular occurrence of Gramineae throughout with strong variation in diversity and frequency of peat swamp taxa represented by Blumeodendron type, Calophyllum type, Stemonurus type Calamus type and Dactylocladus type. The mangrove element such as Rhizophora type exhibits gradual increased in number throughout the FT-I and FT-II zone and showing reduced abundance in FT-III zone. These three zones are correlatable to the Late Oligocene to Early Miocene palynostratigraphy of the Cycle I and Cycle II in the Sarawak Basin. The palynological successions from these areas suggest a typical wet climate with intermittent seasonally dry conditions throughout the Late Oligocene - Early Miocene. This is evident from the regular occurrence of grass pollen i.e., Gramineae/Poaceae with common rain forest and peatswamp elements. This is supported by the common to high frequency of mangrove pollen notably Rhizophora type (Zonocostites ramonae). The Early Miocene may have experienced occasional super wet climatic conditions where rain forest pollen assemblages were prevalent including intermittent acme of Casuarina type pollen.","PeriodicalId":39503,"journal":{"name":"Bulletin of the Geological Society of Malaysia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42632968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acid mine drainage (AMD) at Bukit Besi is often accompanied by high concentrations of various heavy metal such as iron, lead, copper, zink, cadmium, manganese, nikel, and arsenic. The samples were collected from active mining site at Cheng Yu, Bukit Besi. The physical and chemical tests used are ion chromatography (IC) and inductively coupled plasma (ICP) test, toxicity characteristic leaching procedure (TCLP), and clay mineralogy using XRF (X-ray fluorescence) and XRD (X-ray diffraction) techniques. Static test which is acid-base counting are used to predict the potential of AMD. The water analysis showed a very acidic water with pH < 3.5 with high concentration of heavy metals like Fe (822.03 mg/L) and sulfate (4455.87 mg/L). Acid-bases rock calculation shows highly significant results which have high potential of acid production (9.5 to 155.0 kg CaCO3/ton). The results from physical and chemical analysis show Bukit Besi area is potentially exposed to formation of acid mine drainage.
武吉别西的酸性矿井排水（AMD）通常伴有高浓度的各种重金属，如铁、铅、铜、锌、镉、锰、镍和砷。这些样本是从武吉别西成渝的活跃矿区采集的。使用的物理和化学测试包括离子色谱（IC）和电感耦合等离子体（ICP）测试、毒性特征浸出程序（TCLP）以及使用XRF（X射线荧光）和XRD（X射线衍射）技术的粘土矿物学。采用酸碱计数的静态试验来预测AMD的发病潜力。水分析显示，pH＜3.5的酸性水含有高浓度的重金属，如Fe（822.03 mg/L）和硫酸盐（4455.87 mg/L）。酸碱岩石计算显示出非常显著的结果，具有很高的产酸潜力（9.5至155.0 kg CaCO3/吨）。物理和化学分析结果表明，武吉别西地区有可能形成酸性矿井排水。
{"title":"The Potential Of Acid Mine Drainage Formation At Bukit Besi, Dungun, Terengganu","authors":"Nuur Hani Mohammed, Wan Zuhairi Wan Yaacob","doi":"10.7186/bgsm74202210","DOIUrl":"https://doi.org/10.7186/bgsm74202210","url":null,"abstract":"Acid mine drainage (AMD) at Bukit Besi is often accompanied by high concentrations of various heavy metal such as iron, lead, copper, zink, cadmium, manganese, nikel, and arsenic. The samples were collected from active mining site at Cheng Yu, Bukit Besi. The physical and chemical tests used are ion chromatography (IC) and inductively coupled plasma (ICP) test, toxicity characteristic leaching procedure (TCLP), and clay mineralogy using XRF (X-ray fluorescence) and XRD (X-ray diffraction) techniques. Static test which is acid-base counting are used to predict the potential of AMD. The water analysis showed a very acidic water with pH < 3.5 with high concentration of heavy metals like Fe (822.03 mg/L) and sulfate (4455.87 mg/L). Acid-bases rock calculation shows highly significant results which have high potential of acid production (9.5 to 155.0 kg CaCO3/ton). The results from physical and chemical analysis show Bukit Besi area is potentially exposed to formation of acid mine drainage.","PeriodicalId":39503,"journal":{"name":"Bulletin of the Geological Society of Malaysia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44983322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Offshore NW Sabah is one of the localities identified in the United States Geological Survey (USGS) global hydrates database but not much work has been done on this potential source of energy for Malaysia and the surrounding region. The presence of gas hydrates in this area is mainly inferred from bottom-simulating reflectors (BSR) identified in seismic reflection profiles across the margin. BSRs have been mapped across almost the entire length of the deepwater fold-thrust belt in the Sabah Trough where they are commonly observed within the crests of fold-thrust anticlines. Based on an average geothermal gradient of 62.5 °C/km, the thickness of the gas hydrate stability zone is predicted to vary with water depth from zero at 640 m water depth to 300 m at 2900 m water depth. The total in-place methane resource from the Sabah gas hydrates is estimated to range from 72 to 852 trillion cu. ft. (TCF) (2.06 – 24.1 x 1012 m3) with a mean of 364 TCF (10.3 x 1012 m3 ) and a most likely (P50) value of 252 TCF (7.1 x 1012 m3). These preliminary estimates may seem large but they are comparable with those from other gas hydrate deposits in the region. More work is required to refine them in order to determine how much of the in situ volume is technically and economically recoverable.
{"title":"Gas Hydrate Resource Potential Of Deepwater Sabah, Malaysia: A Preliminary Assessment","authors":"M. Madon","doi":"10.7186/bgsm74202201","DOIUrl":"https://doi.org/10.7186/bgsm74202201","url":null,"abstract":"Offshore NW Sabah is one of the localities identified in the United States Geological Survey (USGS) global hydrates database but not much work has been done on this potential source of energy for Malaysia and the surrounding region. The presence of gas hydrates in this area is mainly inferred from bottom-simulating reflectors (BSR) identified in seismic reflection profiles across the margin. BSRs have been mapped across almost the entire length of the deepwater fold-thrust belt in the Sabah Trough where they are commonly observed within the crests of fold-thrust anticlines. Based on an average geothermal gradient of 62.5 °C/km, the thickness of the gas hydrate stability zone is predicted to vary with water depth from zero at 640 m water depth to 300 m at 2900 m water depth. The total in-place methane resource from the Sabah gas hydrates is estimated to range from 72 to 852 trillion cu. ft. (TCF) (2.06 – 24.1 x 1012 m3) with a mean of 364 TCF (10.3 x 1012 m3 ) and a most likely (P50) value of 252 TCF (7.1 x 1012 m3). These preliminary estimates may seem large but they are comparable with those from other gas hydrate deposits in the region. More work is required to refine them in order to determine how much of the in situ volume is technically and economically recoverable.","PeriodicalId":39503,"journal":{"name":"Bulletin of the Geological Society of Malaysia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46585198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Three broad zones can be differentiated at the weathering profile; an upper, 9.4 m thick, pedological soil (zone I), an intermediate, 31.7 m thick, saprock (zone II) and the bottom bedrock (zone III). The saprock (zone II) comprises gravelly silty sands that distinctly preserve the minerals, textures and structures of the original bedrock and can be separated into sub-zones II A, II B, II C and II D based on differences in preservation of relict structures and content of litho-relicts (core-boulders). To characterize the drained strength of saprock, samples were collected from sub-zones II B, II C and II D, and their physical and soil index properties determined before consolidated, drained triaxial tests were carried out on remolded specimens. Three individual specimens from each sub-zone were consolidated for 24 hours and compressed at a rate of 0.152 mm/min under confining pressures of 138 kPa, 207 kPa and 276 kPa. The tests yielded effective cohesions (c’) of 30.6 kPa, 9.5 kPa, and 20.2 kPa, and friction angles of 33.2o, 31.4o and 34.4o, for the samples from sub-zones II B, II C and II D, respectively. Regression analyses show effective cohesions (c’) to increase with increasing moisture contents retained at 4.19 pF (1,500 kPa) suction; a feature indicating the influence of negative pore water pressures (matric suction). Regression analyses also show effective friction angles to increase with increasing sand, and sand and gravel, contents; a feature indicating increased inter-locking and resistance to displacement of coarse particles during shear. It is concluded that the saprock is characterized by an average effective cohesion of 14.5 kPa, and friction angle of 34.3o; these parameters influenced by the moisture content retained at 1,500 kPa suction, and the sand and gravel contents.
{"title":"Drained Shear Strength Parameters Of Saprock From A Weathering Profile Over Porphyritic Biotite Granite At Km 31 Of The Kuala Lumpur - Karak Highway, Peninsular Malaysia","authors":"John Kuna Raj","doi":"10.7186/bgsm74202203","DOIUrl":"https://doi.org/10.7186/bgsm74202203","url":null,"abstract":"Three broad zones can be differentiated at the weathering profile; an upper, 9.4 m thick, pedological soil (zone I), an intermediate, 31.7 m thick, saprock (zone II) and the bottom bedrock (zone III). The saprock (zone II) comprises gravelly silty sands that distinctly preserve the minerals, textures and structures of the original bedrock and can be separated into sub-zones II A, II B, II C and II D based on differences in preservation of relict structures and content of litho-relicts (core-boulders). To characterize the drained strength of saprock, samples were collected from sub-zones II B, II C and II D, and their physical and soil index properties determined before consolidated, drained triaxial tests were carried out on remolded specimens. Three individual specimens from each sub-zone were consolidated for 24 hours and compressed at a rate of 0.152 mm/min under confining pressures of 138 kPa, 207 kPa and 276 kPa. The tests yielded effective cohesions (c’) of 30.6 kPa, 9.5 kPa, and 20.2 kPa, and friction angles of 33.2o, 31.4o and 34.4o, for the samples from sub-zones II B, II C and II D, respectively. Regression analyses show effective cohesions (c’) to increase with increasing moisture contents retained at 4.19 pF (1,500 kPa) suction; a feature indicating the influence of negative pore water pressures (matric suction). Regression analyses also show effective friction angles to increase with increasing sand, and sand and gravel, contents; a feature indicating increased inter-locking and resistance to displacement of coarse particles during shear. It is concluded that the saprock is characterized by an average effective cohesion of 14.5 kPa, and friction angle of 34.3o; these parameters influenced by the moisture content retained at 1,500 kPa suction, and the sand and gravel contents.","PeriodicalId":39503,"journal":{"name":"Bulletin of the Geological Society of Malaysia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45899192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muhammad ‘Izzat ‘Irfan Ahmad Tajuddin, Ying Jia Teoh, C. Choong, B. Sautter, H. Tsegab, M. H. Roselee
Due to dissolution, weathering and erosion, limestone and marble form karstic landscape with precipitous hills, rugged valleys, caves and sinkholes. In the event of an intrusion, the magma, which resides below the limestone bedrock will ascend toward the earth’s surface and fill up the fractures within the pre-existing rocks, forming dikes and sills. Dikes and veins can also be formed when minerals precipitate from hydrothermal fluids within a fracture. The objective of this study was to determine the texture and mineralogy of the dikes cutting the marble in the study area. The findings suggest that the mineral composition and physical structure of the dikes differ from the marble host rock based on its mineral, chemical and physical properties. Three samples were collected and analyzed using Scanning Electron Microscopy (SEM), X-ray diffraction analysis (XRD) and petrographic microscope. The results show that there are at least two types of dike, which are quartz and a coarse-grained granite dike at the study area. The presence of these dikes may affect the chemical and mechanical properties of aggregates produced from the quarry, and in turn affect the excavated rocks of its usage.
{"title":"Characterization Of Dikes At Simpang Pulai Quarry, Perak","authors":"Muhammad ‘Izzat ‘Irfan Ahmad Tajuddin, Ying Jia Teoh, C. Choong, B. Sautter, H. Tsegab, M. H. Roselee","doi":"10.7186/bgsm74202211","DOIUrl":"https://doi.org/10.7186/bgsm74202211","url":null,"abstract":"Due to dissolution, weathering and erosion, limestone and marble form karstic landscape with precipitous hills, rugged valleys, caves and sinkholes. In the event of an intrusion, the magma, which resides below the limestone bedrock will ascend toward the earth’s surface and fill up the fractures within the pre-existing rocks, forming dikes and sills. Dikes and veins can also be formed when minerals precipitate from hydrothermal fluids within a fracture. The objective of this study was to determine the texture and mineralogy of the dikes cutting the marble in the study area. The findings suggest that the mineral composition and physical structure of the dikes differ from the marble host rock based on its mineral, chemical and physical properties. Three samples were collected and analyzed using Scanning Electron Microscopy (SEM), X-ray diffraction analysis (XRD) and petrographic microscope. The results show that there are at least two types of dike, which are quartz and a coarse-grained granite dike at the study area. The presence of these dikes may affect the chemical and mechanical properties of aggregates produced from the quarry, and in turn affect the excavated rocks of its usage.","PeriodicalId":39503,"journal":{"name":"Bulletin of the Geological Society of Malaysia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48957875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aubrey Marie Villareal-Tirona, M. Balangue-Tarriela, R. Shaw
The Jugan Gold Deposit (JGD) is part of the Bau Mineral District (BMD) in Bau, Sarawak, East Malaysia. Although the mineral district is well studied, limited studies were conducted on the JGD. This paper presents the results of statistical studies using the multi-element geochemical data emphasizing the trace elements association with gold, alteration-mineralization, and the precipitation mechanism of the gold-bearing sulfide minerals. The correlation matrix displays positive correlation associations, particularly those associated with gold mineralization, i.e., arsenic, sulfur, antimony, and bismuth. Factor analysis grouped the trace elements into eight factors that reflect lithologies, mineralization, alteration, and geological processes in the JGD. Elements comprising the gold mineralization assemblage have the most significant factor (Factor 1) with the highest variance. The mineral assemblage was enriched during the alteration-mineralization process, as confirmed by the isocon plot. The barren samples (<0.01g/t) and gold-bearing samples (>0.2 g/t) plotted in a Fe vs. S diagram indicate that sulfidation is the precipitation mechanism of gold-bearing sulfide minerals. The immobility of iron and the vertical trajectory trend in the Fe vs. S diagram suggest that the possible source of Fe for gold-bearing sulfide minerals is the sedimentary host rock. Collectively, characteristics such as (1) the association of gold-bearing sulfide minerals with carbonate mineral assemblage and (2) high bismuth loadings on the main mineralization stage suggest a distinct geochemical characteristic of JGD relative to both Carlin-type deposits (CTD) and Carlin-like deposits (CLD); hence it is inferred to be a sedimentary-hosted gold deposit (SHGD). Establishing the JGD characteristics will contribute to a better understanding of the deposit and the BMD. Exploration-wise, it will assist future exploration work in delineating Au mineralization zones.
{"title":"Sulfidation And Gold Precipitation In The Jugan Gold Deposit In Bau, Sarawak, East Malaysia: Insights From Correlation Plots And Factor Analysis","authors":"Aubrey Marie Villareal-Tirona, M. Balangue-Tarriela, R. Shaw","doi":"10.7186/bgsm74202204","DOIUrl":"https://doi.org/10.7186/bgsm74202204","url":null,"abstract":"The Jugan Gold Deposit (JGD) is part of the Bau Mineral District (BMD) in Bau, Sarawak, East Malaysia. Although the mineral district is well studied, limited studies were conducted on the JGD. This paper presents the results of statistical studies using the multi-element geochemical data emphasizing the trace elements association with gold, alteration-mineralization, and the precipitation mechanism of the gold-bearing sulfide minerals. The correlation matrix displays positive correlation associations, particularly those associated with gold mineralization, i.e., arsenic, sulfur, antimony, and bismuth. Factor analysis grouped the trace elements into eight factors that reflect lithologies, mineralization, alteration, and geological processes in the JGD. Elements comprising the gold mineralization assemblage have the most significant factor (Factor 1) with the highest variance. The mineral assemblage was enriched during the alteration-mineralization process, as confirmed by the isocon plot. The barren samples (<0.01g/t) and gold-bearing samples (>0.2 g/t) plotted in a Fe vs. S diagram indicate that sulfidation is the precipitation mechanism of gold-bearing sulfide minerals. The immobility of iron and the vertical trajectory trend in the Fe vs. S diagram suggest that the possible source of Fe for gold-bearing sulfide minerals is the sedimentary host rock. Collectively, characteristics such as (1) the association of gold-bearing sulfide minerals with carbonate mineral assemblage and (2) high bismuth loadings on the main mineralization stage suggest a distinct geochemical characteristic of JGD relative to both Carlin-type deposits (CTD) and Carlin-like deposits (CLD); hence it is inferred to be a sedimentary-hosted gold deposit (SHGD). Establishing the JGD characteristics will contribute to a better understanding of the deposit and the BMD. Exploration-wise, it will assist future exploration work in delineating Au mineralization zones.","PeriodicalId":39503,"journal":{"name":"Bulletin of the Geological Society of Malaysia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43770921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. A, S. Sahari, N. B., N. A.M., Fu Fui, A. Ashwini, T. Q.
The western Himalayan syntaxis represents the region where the major Himalayan structures abruptly curve and the cause of the curvature and the tectonic geomorphology of the region has not been fully explored. The lack of detailed structural maps with extensive field-based data are missing, which is mainly because of the political problems related to border sharing between Pakistan, India, and Afghanistan. However, and fortunately, the usage of satellite derived images has overcome such constrains by providing a robust platform to remotely map such regions. Therefore, the present study was aimed to supplement our previous works in the region by exploring the western portions of the Hazara-Kashmir-Syntaxis. We have used Google terrain imagery to map the evidence for active faulting that involves mapping of triangular facets, displaced and/or faulted topographic ridges, river terraces, alluvial fans and so on. The crosscutting relationships are used to date the faulting events where absolute dates are not available. Our results show that active tectonic deformation is not just limited to the previously mapped structures (e.g. the Kalabagh Fault, the Salt Range Thrust, the Mahesian Anticline, and the Jhelum Fault) but occurs on a broader deformation zone that is delimited by the Chaman fault system in the west, and the Jhelum Fault in the east. The deformation zone in 3D resembles a tectonically formed diamond shaped box that has Salt Range Thrust in front and the Main Boundary Fault at the back with sides delimited by the Chaman and the Jhelum fault systems. The earthquake centroid moment tensor data compliments our geomorphological work, and establishes that transpression is a dominant tectonic process that governs the western regions, which is in comparison to the east where transtension is the norm in the interior Himalayan with reverse and thrust faulting dominant in the frontal regions.
{"title":"Tectonic Geomorphology Of The Jhelum Fault Zone And Its Contiguous Regions In Western Himalaya","authors":"S. A, S. Sahari, N. B., N. A.M., Fu Fui, A. Ashwini, T. Q.","doi":"10.7186/bgsm73202210","DOIUrl":"https://doi.org/10.7186/bgsm73202210","url":null,"abstract":"The western Himalayan syntaxis represents the region where the major Himalayan structures abruptly curve and the cause of the curvature and the tectonic geomorphology of the region has not been fully explored. The lack of detailed structural maps with extensive field-based data are missing, which is mainly because of the political problems related to border sharing between Pakistan, India, and Afghanistan. However, and fortunately, the usage of satellite derived images has overcome such constrains by providing a robust platform to remotely map such regions. Therefore, the present study was aimed to supplement our previous works in the region by exploring the western portions of the Hazara-Kashmir-Syntaxis. We have used Google terrain imagery to map the evidence for active faulting that involves mapping of triangular facets, displaced and/or faulted topographic ridges, river terraces, alluvial fans and so on. The crosscutting relationships are used to date the faulting events where absolute dates are not available. Our results show that active tectonic deformation is not just limited to the previously mapped structures (e.g. the Kalabagh Fault, the Salt Range Thrust, the Mahesian Anticline, and the Jhelum Fault) but occurs on a broader deformation zone that is delimited by the Chaman fault system in the west, and the Jhelum Fault in the east. The deformation zone in 3D resembles a tectonically formed diamond shaped box that has Salt Range Thrust in front and the Main Boundary Fault at the back with sides delimited by the Chaman and the Jhelum fault systems. The earthquake centroid moment tensor data compliments our geomorphological work, and establishes that transpression is a dominant tectonic process that governs the western regions, which is in comparison to the east where transtension is the norm in the interior Himalayan with reverse and thrust faulting dominant in the frontal regions.","PeriodicalId":39503,"journal":{"name":"Bulletin of the Geological Society of Malaysia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47632948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kamal Haji Karim Haji Karim, Hiyam Daoud, Rzger Abdula, Arkan O. Sharezwri
The present study focuses on the presentation of field and laboratory evidences for the first record of the Aqra Formation (Maastrichtian) outcrop at the top of the Tanjero Formation in the Soran area, Erbil Governorate. The previous studies indicated its outcrops as Middle Miocene Govanda Formation between Merga Red Bed Series and Tanjero Formation. The present study discusses relations of this outcrop with Govanda and Bekhme formations in the Sulaimani and Duhok governorates in terms of environment and tectonics. In the Soran area, the formation has variable thickness ranging between 2-160 m and underlies either Red Bed Series or Govanda Formation (Middle Miocene). The study documented many stratigraphic and paleontological evidences to prove occurrence of the Aqra Formation in the area. Additionally, we discussed the significance of its occurrence in detail by which many tectonic and stratigraphic issues of the area are unlocked. One of the issues is occurrence of Tanjero Formation between the Aqra and Bekhme formations and it separates the two formations in two different age ranges and tectonic episodes. Another issue is the documentation of the occurrence of the Aqra Formation inside the Thrust Zone by which the distribution of the formation is extendable beyond Main Zagros Thrust Fault. The study includes a detailed stratigraphic column and tectonic model of the formation to show the coastal area, patchy reef, and shelf environment of the Aqra Formation.
{"title":"Occurrence And Relationship Of The Aqra, Bekhme And Govanda Formations In The Soran (Rawanduz) Area, Kurdistan Region, Northeastern Iraq","authors":"Kamal Haji Karim Haji Karim, Hiyam Daoud, Rzger Abdula, Arkan O. Sharezwri","doi":"10.7186/bgsm73202206","DOIUrl":"https://doi.org/10.7186/bgsm73202206","url":null,"abstract":"The present study focuses on the presentation of field and laboratory evidences for the first record of the Aqra Formation (Maastrichtian) outcrop at the top of the Tanjero Formation in the Soran area, Erbil Governorate. The previous studies indicated its outcrops as Middle Miocene Govanda Formation between Merga Red Bed Series and Tanjero Formation. The present study discusses relations of this outcrop with Govanda and Bekhme formations in the Sulaimani and Duhok governorates in terms of environment and tectonics. In the Soran area, the formation has variable thickness ranging between 2-160 m and underlies either Red Bed Series or Govanda Formation (Middle Miocene). The study documented many stratigraphic and paleontological evidences to prove occurrence of the Aqra Formation in the area. Additionally, we discussed the significance of its occurrence in detail by which many tectonic and stratigraphic issues of the area are unlocked. One of the issues is occurrence of Tanjero Formation between the Aqra and Bekhme formations and it separates the two formations in two different age ranges and tectonic episodes. Another issue is the documentation of the occurrence of the Aqra Formation inside the Thrust Zone by which the distribution of the formation is extendable beyond Main Zagros Thrust Fault. The study includes a detailed stratigraphic column and tectonic model of the formation to show the coastal area, patchy reef, and shelf environment of the Aqra Formation.","PeriodicalId":39503,"journal":{"name":"Bulletin of the Geological Society of Malaysia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42683457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hamid A. A. Alsultan, F. Maziqa, Mohanad R. A. Al-Owaidi
The carbonate platform is the environment of Khasib, Tanuma and Sa’di formations which were deposited within open shelf settings at the Majnoon oil field in eight microfacies. The deposition, based on the analysis of microfacies, took place within shallow open marine, shoal environment, deep marine and basin environments. Five third order cycles of succession consist in MJ-12 oil well and three third order cycles in the MJ-15 oil well. They represent successive episodes of sea level rise and standstills. The succession in the study area was formed in a high subsidence environment, reflecting the high subsidence as the main controlling factor in the sequence creation. Because of a significant transgression, the Khasib, Tanuma, and Sa’di formations were deposited on an extremely subsidential carbonate base, where sea level succession involved episodes of rise and standstills.
{"title":"A Stratigraphic Analysis Of The Khasib, Tanuma And Sa’di Formations In The Majnoon Oil Field, Southern Iraq","authors":"Hamid A. A. Alsultan, F. Maziqa, Mohanad R. A. Al-Owaidi","doi":"10.7186/bgsm73202213","DOIUrl":"https://doi.org/10.7186/bgsm73202213","url":null,"abstract":"The carbonate platform is the environment of Khasib, Tanuma and Sa’di formations which were deposited within open shelf settings at the Majnoon oil field in eight microfacies. The deposition, based on the analysis of microfacies, took place within shallow open marine, shoal environment, deep marine and basin environments. Five third order cycles of succession consist in MJ-12 oil well and three third order cycles in the MJ-15 oil well. They represent successive episodes of sea level rise and standstills. The succession in the study area was formed in a high subsidence environment, reflecting the high subsidence as the main controlling factor in the sequence creation. Because of a significant transgression, the Khasib, Tanuma, and Sa’di formations were deposited on an extremely subsidential carbonate base, where sea level succession involved episodes of rise and standstills.","PeriodicalId":39503,"journal":{"name":"Bulletin of the Geological Society of Malaysia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43893739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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