Why don’t we look to the west?

Paleontological data indicate that the beginning of Java Island’s human habitation took place at the Plio-Pleistocene boundary, around 2.4 Ma, along with uplift process and glacial-interglacial cycles. However, the oldest Homo erectus fossil was mainly found in the eastern part of Java Island where age-dating indicates that they were from ca. 1.5 Ma, especially along the riverbanks of Bengawan Solo and Brantas, such as Perning, Sangiran, Kedungbrubus, Ngandong, Ngawi, Trinil, and Sambungmacan.Recently, Pleistocene sites were discovered from the western part of Java, e.g., Rancah (Ciamis), Semedo (Tegal), and Bumiayu (Brebes) with their archeological, paleontological, and paleoanthropological potentials. This work will present the significance of the potential, especially paleoanthropological data from the new sites, and their implications to the Quaternary prehistory research strategies determination in the future.We present new geological, archeological, paleontological, and paleoanthropological evidence from those mentioned sites. The result shows that the distribution of Homo erectus were extended to the western part of Java, between 1.8-1.7 Ma, older than the oldest previous finding of Homo erectus from Perning and Sangiran. This finding suggests a new window of the human arrival on this island. So, why don’t we look to the west? Intensive research in the future should be addressed to the western part of Java Island.

NEW AMS 14C DATES OF A MULTICULTURAL ARCHAEOLOGICAL SITE FROM THE PALEO-DELTAIC REGION OF WEST BENGAL, INDIA: CULTURAL AND GEO-ARCHAEOLOGICAL IMPLICATIONS

ABSTRACT This study is on the absolute age dating of a multicultural site of Erenda, East Medinipur district, in coastal West Bengal, India. Charcoal samples were collected and measured using the accelerator mass spectrometry (AMS) facility at the Inter-University Accelerator Centre, New Delhi, India. These samples were collected from secured stratigraphic context of two excavated trenches. A careful collection of samples from two trenches provided us with the first calendar dates, 950 BCE and 1979 BCE, of protohistoric sites in coastal West Bengal. These calibrated calendar dates not only have wider significance in terms of archaeology but also methodological implications to understand the relevance of application of AMS from the dynamic coastal landscape in the humid tropics during the late Holocene period.

Hydrothermal Fluids and Cold Meteoric Waters along Tectonic-Controlled Open Spaces in Upper Cretaceous Carbonate Rocks, NE-Iraq: Scanning Data from In Situ U-Pb Geochronology and Microthermometry

The Upper Cretaceous carbonates along the Zagros thrust-fold belt “Harir-Safin anticlines” experienced extensive hot brine fluids that produced several phases of hydrothermal cements, including saddle dolomites. Detailed fluid inclusion microthermometry data show that saddle dolomites precipitated from hydrothermal (83–160 °C) and saline fluids (up to 25 eq. wt.% NaCl; i.e., seven times higher than the seawater salinity). The fluids interacted with brine/rocks during their circulation before invading the Upper Cretaceous carbonates. Two entrapment episodes (early and late) of FIs from the hydrothermal “HT” cements are recognized. The early episode is linked to fault-related fractures and was contemporaneous with the precipitation of the HT cements. The fluid inclusions leaked and were refilled during a later diagenetic phase. The late episode is consistent with low saline fluids (0.18 and 2.57 eq. wt.% NaCl) which had a meteoric origin. Utilizing the laser ablation U-Pb age dating method, two numerical absolute ages of ~70 Ma and 3.8 Ma are identified from calcrete levels in the Upper Cretaceous carbonates. These two ages obtained in the same level of calcrete indicate that this unit was twice exposed to subaerial conditions. The earlier exposure was associated with alveolar and other diagenetic features, such as dissolution, micritization, cementation, while the second calcrete level is associated with laminae, pisolitic, and microstromatolite features which formed during the regional uplifting of the area in Pliocene times. In conclusion, the hydrothermal-saddle dolomites were precipitated from high temperature saline fluids, while calcrete levels entrapped large monophase with very low salinity fluid inclusions, indicative for a low temperature precipitation from water with a meteoric origin.

Regional Tectonics to Basin Fill Architecture from Aptian Shuaiba Fm to Miocene Fars Gp of Abu Dhabi

Objectives/Scope Aptian (Shuaiba-Bab) and Cenomanian (Mishrif-Shilaif) intra-shelf basins were extensively studied with their genesis focused on environmental/climatic disturbances (Vahrenkamp et al., 2015a). Additionally, local tectonic events can also affect the physiography of these basins, especially the Cenomanian intra-shelf basin subjected to NE compressional regime. As this ongoing regime increased at Late-Cretaceous and Miocene, it led to more tectonic-driven basin physiography. This paper investigates the areal extent, interaction, and commonalities between the extensional Aptian intra-shelf basin, compressional Late-Cretaceous intra-shelf basin, Late-Cretaceous-Paleogene foreland basin, and Late Oligocene-Miocene salt basin. Methods, Procedures, Process To understand the genesis, driving forces, and distribution of these basins, we used a combination of several large-scale stratigraphic well correlations and seismic, together with age dating, cores, and extensive well information (ADNOC proprietary internal reports). The methodology used this data for detailed mapping of 11 relevant time stratigraphic intervals, placing the mapped architecture in the context of the global eustatic sea level and major geodynamic events of the Arabian Plate. Results, Observations, Conclusions Aptian basin took place as a consequence of environmental/climatic disturbances (Vahrenkamp et al., 2015a). However, environmental factors alone cannot explain isolated carbonate build-ups on salt-related structures at the intra-shelf basin, offshore Abu Dhabi. Subsequently, the emplacement of thrust sheets of Tethyan rocks from NE, and following ophiolite obduction (Searle et al., 1990; Searle, 2007; Searle and Ali, 2009; Searle et al., 2014), established a compressional regime in the Albian?-Cenomanian. This induced tectonic features such as: loading-erosion on eastern Abu Dhabi, isolated carbonate build-ups, and reactivation of a N-S deep-rooted fault (possibly a continuation of Precambrian Amad basement ridge from KSA). This N-S feature was probably the main factor contributing the basin axis change from E-W Aptian trend to N-S position at Cenomanian. Further compression continued into the Coniacian-Santonian, leading to a nascent foreland basin. This compression established a foredeep in eastern Abu Dhabi, separated by a bulge from the northern extension of the eastern Rub’ Al-Khali basin (Ghurab syncline) (Patton and O'Connor, 1988). Numerous paleostructures were developed onshore Abu Dhabi, together with several small patch-reefs on offshore salt growing structures. Campanian exhibits maximum structuration associated to eastern transpression related to Masirah ophiolite obduction during India drift (Johnson et al., 2005, Filbrandt et al., 2006; Gaina et al., 2015). This caused more differentiation of the foredeep, onshore synclines, and northern paleostructures, which continued to cease through Maastrichtian. From Paleocene to Late-Eocene, paleostructure growth intensity continued decreasing and foreland basin hydrological restriction began with the Neotethys closure. Through Oligocene until Burdigalian this situation continued, where the Neotethys closed with the Zagros Orogeny (Sharland et al., 2001), causing a new environmental/climatic disturbances period. These disturbances prevented the continued progradation of the carbonate factory into the foredeep, leading to conspicuous platform-basin differentiation. Additionally, the Zagros orogeny tilted the plate northeastward, dismantling the paleostructures generated at Late-Cenomanian. Finally, during an arid climate in the Burdigalian to Middle-Miocene, the confined Neogene sea filled the foredeep accommodation space with massive evaporites. Novel/Additive Information Little has been published about the outline and architecture of these basins in Abu Dhabi and the detailed circumstances that led to their genesis using subsurface information.

Bedrock to soil: In-situ measurement and analytical techniques for initial weathering of proglacial environments

<p>Dirt. It is more important than one might think. Soil, along with its bedrock-derived components, provides a nexus in the earth system for energy, nutrient, and atmospheric control; yet it is a finite resource. Soils are consumed, transported, and replenished by natural and anthropogenic forces. Weathering—both physical and chemical—is the key process breaking down and regenerating the ions and mineral constituents of soils, facilitating the pathways from solid bedrock to soil to the rest of the global ecosystem. Yet our understanding of weathering is incomplete and the available methods to investigate these processes are limited. Here, the fundamental processes of weathering are questioned by studying them at their origins, the rock surface. New techniques were developed in pursuit of quantifying weathering at small scales in-situ, to obtain the highest resolution measurements possible. These were carried out in the proglacial regions of two New Zealand glaciers, Brewster Glacier and Franz Josef Glacier. Proglacial bedrock environments provided a clean-slate model from which to measure incipient weathering at increasing exposure ages. To mitigate error, a holistic approach encompassing weathering signals from multiple angles was taken. Spatial characterisation was completed through the capture of structure-from-motion photogrammetry (SFM) at multiple scales of observation. The resultant three dimensional surface models had an average error of 1.06x10-1 mm. The models were characterised for weathering using roughness as a novel multi-point analysis of surface features, through two separate novel methods utilising global polynomial interpolation filtering and continuous wavelet transform analysis. Physical samples were collected from the field for cosmogenic radionuclide surface exposure age dating. Compositional analysis was performed through X-ray fluorescence, as well as electron microprobe analysis (EPMA). Nano-scale structural and compositional trends were investigated through optical analysis of backscatter electron imaging and secondary electron imaging. Non-directional roughness and volumetric analysis patterns present compelling information to support negligible weathering occurring on bedrock surfaces in proglacial environments. Lithologic variation was identified as a strong influence on the results. Compositional analysis demonstrated insignificant levels of chemical alteration between sites, corroborating the spatial modelling results. The lack of surficial weathering in highly productive weathering environments necessitates the role of additional weathering factors. Deep subsurface weathering was investigated and presents the strongest case as a major contributor to chemical denudation. Validating the presence of deep weathering in many environments critically alters the knowledge required to evaluate and predict patterns of landscape evolution. By establishing a better understanding of how bedrock weathers in-situ, the groundwork is laid for making more accurate and educated forecasts on how the earth system will respond to changes in the future.</p>

Bedrock to soil: In-situ measurement and analytical techniques for initial weathering of proglacial environments

<p>Dirt. It is more important than one might think. Soil, along with its bedrock-derived components, provides a nexus in the earth system for energy, nutrient, and atmospheric control; yet it is a finite resource. Soils are consumed, transported, and replenished by natural and anthropogenic forces. Weathering—both physical and chemical—is the key process breaking down and regenerating the ions and mineral constituents of soils, facilitating the pathways from solid bedrock to soil to the rest of the global ecosystem. Yet our understanding of weathering is incomplete and the available methods to investigate these processes are limited. Here, the fundamental processes of weathering are questioned by studying them at their origins, the rock surface. New techniques were developed in pursuit of quantifying weathering at small scales in-situ, to obtain the highest resolution measurements possible. These were carried out in the proglacial regions of two New Zealand glaciers, Brewster Glacier and Franz Josef Glacier. Proglacial bedrock environments provided a clean-slate model from which to measure incipient weathering at increasing exposure ages. To mitigate error, a holistic approach encompassing weathering signals from multiple angles was taken. Spatial characterisation was completed through the capture of structure-from-motion photogrammetry (SFM) at multiple scales of observation. The resultant three dimensional surface models had an average error of 1.06x10-1 mm. The models were characterised for weathering using roughness as a novel multi-point analysis of surface features, through two separate novel methods utilising global polynomial interpolation filtering and continuous wavelet transform analysis. Physical samples were collected from the field for cosmogenic radionuclide surface exposure age dating. Compositional analysis was performed through X-ray fluorescence, as well as electron microprobe analysis (EPMA). Nano-scale structural and compositional trends were investigated through optical analysis of backscatter electron imaging and secondary electron imaging. Non-directional roughness and volumetric analysis patterns present compelling information to support negligible weathering occurring on bedrock surfaces in proglacial environments. Lithologic variation was identified as a strong influence on the results. Compositional analysis demonstrated insignificant levels of chemical alteration between sites, corroborating the spatial modelling results. The lack of surficial weathering in highly productive weathering environments necessitates the role of additional weathering factors. Deep subsurface weathering was investigated and presents the strongest case as a major contributor to chemical denudation. Validating the presence of deep weathering in many environments critically alters the knowledge required to evaluate and predict patterns of landscape evolution. By establishing a better understanding of how bedrock weathers in-situ, the groundwork is laid for making more accurate and educated forecasts on how the earth system will respond to changes in the future.</p>

Geology and Geothermal Setting of Tompaso Geothermal System, Indonesia, with Comparisons of Andesite Alteration Patterns with Wairakei, New Zealand

<p>Tompaso geothermal system is a typical volcanic arc geothermal system in North Sulawesi, Indonesia. Although situated close to the Tondano caldera, subsurface lithologies and structures do not show any evidence for caldera-related features and the system is inferred to be related to the andesitic Soputan volcano. The subsurface geology of Tompaso consists of Tuff B unit, Rhyolite unit, Andesite B unit, Pitchstone unit, Pyroclastic Breccia unit,Andesite A unit, Pumice unit, and Tuff A unit, respectively, from the oldest penetrated unit. The silicic Pitchstone and Rhyolite units are presumed to be sourced from the same magma chamber. Petrological and mineralogical observations using binocular and petrographic microscopy, short-wave infrared (SWIR) analysis, and back-scattered electron (BSE) imaging combined with energy dispersive X-ray spectroscopy (EDS) have been applied to cuttings and limited core material from three boreholes: LHD-26, LHD-27, and LHD-32. Age dating has not been undertaken and, thus, conclusions on correlations between subsurface geology inferred here with surface formation groupings from previous works cannot be drawn. Tompaso geothermal system is characterised primarily by variations in the fracturing within the reservoir. Secondary mineralogy and the structure of present-day temperature of the system suggest that the movement of hydrothermal fluids at Tompaso is controlled by faults: the Soputan, Tempang, and A-A’ faults, the last defined for the first time in this thesis. Soputan Fault controls the outflow of the system. On the other hand, the influence of Tempang and A-A’ faults is dominant only in the upper portion of the system. The A-A’ fault likely acts as a channel for cooler meteoric surface water, while the Tempang Fault is inferred to have experienced self-sealing and appears to be an impermeable structure in the system. The self-sealing process of the Tempang Fault and/or the introduction of meteoric water through the A-A’ fault may be related to the cooling of the northern and western part of the system. The challenges in identifying protoliths in active geothermal areas is addressed here through studies of the influence of andesite textures on the preferences of hydrothermal alteration processes. Wairakei andesites were chosen for comparison to Tompaso andesites, especially because of its different geological setting and geothermal reservoir structure. The results suggest that mineral composition and arrangement affect the preference of hydrothermal alteration on andesites.</p>

Geology and Geothermal Setting of Tompaso Geothermal System, Indonesia, with Comparisons of Andesite Alteration Patterns with Wairakei, New Zealand

<p>Tompaso geothermal system is a typical volcanic arc geothermal system in North Sulawesi, Indonesia. Although situated close to the Tondano caldera, subsurface lithologies and structures do not show any evidence for caldera-related features and the system is inferred to be related to the andesitic Soputan volcano. The subsurface geology of Tompaso consists of Tuff B unit, Rhyolite unit, Andesite B unit, Pitchstone unit, Pyroclastic Breccia unit,Andesite A unit, Pumice unit, and Tuff A unit, respectively, from the oldest penetrated unit. The silicic Pitchstone and Rhyolite units are presumed to be sourced from the same magma chamber. Petrological and mineralogical observations using binocular and petrographic microscopy, short-wave infrared (SWIR) analysis, and back-scattered electron (BSE) imaging combined with energy dispersive X-ray spectroscopy (EDS) have been applied to cuttings and limited core material from three boreholes: LHD-26, LHD-27, and LHD-32. Age dating has not been undertaken and, thus, conclusions on correlations between subsurface geology inferred here with surface formation groupings from previous works cannot be drawn. Tompaso geothermal system is characterised primarily by variations in the fracturing within the reservoir. Secondary mineralogy and the structure of present-day temperature of the system suggest that the movement of hydrothermal fluids at Tompaso is controlled by faults: the Soputan, Tempang, and A-A’ faults, the last defined for the first time in this thesis. Soputan Fault controls the outflow of the system. On the other hand, the influence of Tempang and A-A’ faults is dominant only in the upper portion of the system. The A-A’ fault likely acts as a channel for cooler meteoric surface water, while the Tempang Fault is inferred to have experienced self-sealing and appears to be an impermeable structure in the system. The self-sealing process of the Tempang Fault and/or the introduction of meteoric water through the A-A’ fault may be related to the cooling of the northern and western part of the system. The challenges in identifying protoliths in active geothermal areas is addressed here through studies of the influence of andesite textures on the preferences of hydrothermal alteration processes. Wairakei andesites were chosen for comparison to Tompaso andesites, especially because of its different geological setting and geothermal reservoir structure. The results suggest that mineral composition and arrangement affect the preference of hydrothermal alteration on andesites.</p>

Schmidt hammer exposure-age dating of periglacial and glacial landforms in the Southern Swiss Alps based on <i>R</i>-value calibration using historical data

As a contribution to the palaeoenvironmental history reconstruction of the Alpine periglacial domain, this study focuses on the Schmidt hammer exposure-age dating (SHD) of (peri-)glacial landforms using rebound-value (R-value) calibrations for 10 stations in the Scaradra glacier forefield (north-eastern part of the Ticino Canton, Lepontine Alps) and for 13 stations in the Splügenpass region (located between Switzerland and Italy, Rhaetian Alps). Linear calibration based on the known age of several moraines of the Scaradra glacier assessed by historical cartography allowed the reconstruction of the glacier fluctuations around the end of the Little Ice Age. Timing of deglaciation and of rock glacier development was defined in the Splügenpass region using the calibration of exposure ages based on two mule tracks built in 300 CE and 1250 CE, respectively. Discussion on R-value analysis and calibration improves the knowledge on the potential use of SHD for numerical-age dating in Alpine geomorphological studies.