RECENT GEOLOGICAL AND GEOPHYSICAL RESULTS IN THE NORTHEASTERN CANNING BASIN

1975 ◽  
Vol 15 (1) ◽  
pp. 1
Author(s):  
M. F. Drew ◽  
G. R. Evans
Keyword(s):  
High Sensitivity ◽  
Structural Features ◽  
Petroleum Exploration ◽  
Seismic Exploration ◽  
Structural Elements ◽  
Seismic Surveys ◽  
Canning Basin ◽  
Reflection Seismic ◽  
Magnetic Basement ◽  
Southern Flank

The exploration programme conducted in Exploration Permits 58 and 59 in the northeastern Canning Basin during the past three years has clarified regional structural and stratigraphic relationships. Interpretation of the combined results of field geological, high sensitivity aeromagnetic and reflection seismic surveys has delineated five major structural elements, some previously unrecognised. These are, from north to south, the Billiluna Shelf, the Betty Terrace, the Fitzroy Trough, the Crossland Platform and the Helena Platform. Sedimentary rocks from Proterozoic to Mesozoic age occur in the permits. The Phanerozoic rocks range in thickness from in excess of 15000 m in the Fitzroy Trough to a veneer of probably less than 1000 m over the Billiluna Shelf. On the Crossland Platform and the Helena Platform, up to 4000 m of Lower and Middle Palaeozoic rocks overlain by up to 1500 m of Upper Palaeozoic sediments are interpreted to be present.Whilst no wells have been drilled within the area, results of exploratory holes in adjoining permits have been used to refine the interpretations presented in this paper. The principal stratigraphic features of interest to petroleum exploration are a possible Devonian reef trend located on the junction of the Crossland and Helena Platforms and subdued structural features caused by halokinesis on the Helena Platform.Two major geological conclusions were drawn from the exploration programme to date. One is that the age of the formation of the Fitzroy Trough, at least in this part of the Canning Basin, is younger than previously postulated. The other is the presence in the northeastern part of the Canning Basin of a Proterozoic infrabasin with depths to magnetic basement comparable with measured outcrop thicknesses on the southern flank of the Kimberley Block.Future exploration plans for the region call for further seismic exploration and the drilling of medium depth wildcat tests to investigate the hydrocarbon potential of the region.

scholarly journals Cetacean behavioral responses to noise exposure generated by seismic surveys: how to mitigate better?

2016 ◽  
Vol 59 (4) ◽  
Author(s):  
Clara Monaco ◽  
Jesús M. Ibáñez ◽  
Francisco Carrión ◽  
L. Mario Tringali
Keyword(s):  
Noise Exposure ◽  
Behavioral Responses ◽  
Seismic Survey ◽  
Seismic Exploration ◽  
Mitigation Measures ◽  
Seismic Surveys ◽  
Reflection Seismic ◽  
Joint Nature Conservation Committee ◽  
Air Gun ◽  
Southern Mediterranean

<p>Cetaceans use sound in many contexts, such as in social interactions, as well as to forage and to react in dangerous situations. Little information exists to describe how they respond physically and behaviorally to intense and long-term noise levels. Effects on cetaceans from seismic survey activities need to be understood in order to determine detailed acoustic exposure guidelines and to apply appropriated mitigation measures. This study examines direct behavioral responses of cetaceans in the southern Mediterranean Sea during seismic surveys with large airgun arrays (volume up to 5200 ci) used in the TOMO-ETNA active seismic experiment of summer 2014. Wide Angle Seismic and Multi-Channel Seismic surveys had carried out with refraction and reflection seismic methods, producing about 25,800 air-gun shots. Visual monitoring undertaken in the 26 daylights of seismic exploration adopted the protocol of the Joint Nature Conservation Committee. Data recorded were analyzed to examine effects on cetaceans. Sighting rates, distance and orientation from the airguns were compared for different volume categories of the airgun arrays. Results show that cetaceans can be disturbed by seismic survey activities, especially during particularly events. Here we propose many integrated actions to further mitigate this exposure and implications for management.</p>

The application of ambient noise and reflection seismic exploration in an urban active fault survey

2020 ◽  
Vol 8 (4) ◽  
pp. SU1-SU10
Author(s):  
Xiaoqiong Lei ◽  
Jun Zhang ◽  
Wenyuan Jin ◽  
Chen Han ◽  
Xiwei Xu
Keyword(s):  
High Resolution ◽  
Ambient Noise ◽  
Active Fault ◽  
Active Faults ◽  
Seismic Exploration ◽  
Deep Penetration ◽  
Seismic Surveys ◽  
Reflection Seismic ◽  
Active Source ◽  
Seismic Lines

As the detection of urban active faults becomes increasingly important, high-resolution detection of urban blind active faults is very important for urban planning, land use, and disaster risk reduction. However, it is difficult to determine the corresponding surface positions in the city environment for noise and building restrictions. The active source reflection seismic technique is considered the best technique to image faults with a high resolution and deep penetration. However, urban geophysical exploration must often consider the complex urban environment, which includes moving vehicles, dense power grids, and irregular buildings. These features make active source reflection seismic exploration difficult for wide application due to its drawbacks of high cost and the necessary use of explosives. In contrast, ambient noise seismic surveys have the advantages of continuous ambient noise sources, low cost, and fast deployment. These advantages are good for urban exploration. Although ambient noise seismic surveys have a lower resolution than active seismic surveys, their ultrahigh-density layout can improve the resolution. We have conducted two active source seismic lines and two ambient noise seismic lines near the Huangzhuang-Gaoliying fault (HGF) in a northern suburb of Beijing. The autocorrelation and crosscorrelation results are consistent with the active source reflection seismic results. They revealed the location of the HGF, which is composed of a set of steep dip faults. The study of the combination of the two techniques demonstrates that ambient noise seismic surveys are effective for urban active fault detection, especially for larger scale area surveys, and active source reflection seismic surveys can be used for detailed surveys. The combination of the two techniques has a higher efficiency and lower costs and can be widely used in blind urban active fault surveys.

THE GEOLOGY OF THE OFFSHORE CANNING BASIN, WESTERN AUSTRALIA

1970 ◽  
Vol 10 (1) ◽  
pp. 78 ◽  
Author(s):  
A. Challinor
Keyword(s):  
Western Australia ◽  
Close Association ◽  
Structural Features ◽  
Geophysical Data ◽  
Petroleum Exploration ◽  
Canning Basin ◽  
Hydrocarbon Reservoir ◽  
Geophysical Surveys ◽  
Australian Continent ◽  
Carnarvon Basin

The Canning Basin is a major geological province of Western Australia and of the Australian continent. It constitutes a major crustal down-warp between the Precambrian Kimberley and Pilbara Blocks and extends offshore onto the wide Rowley Shelf. A large part of this shelf is held under petroleum exploration permit by a group of companies of which B.O.C. of Australia Limited is operator.To date no wells have been drilled in this offshore Canning Basin but extensive geophysical surveys have allowed an interpretive geological model to be presented. This model is based upon an interpretation of geophysical data by extrapolation from offshore data and well control in the Carnarvon Basin and onshore well, outcrop and geophysical data in the Canning Basin.The major Palaeozoic structural features of the Broome Swell and Fitzroy Graben which characterise the onshore Canning Basin extend offshore beneath Mesozoic and Tertiary cover. Thick Palaeozoic and Permo-Triassic sediments are thus expected offshore in the Fitzroy Graben extension and in a major sub-basin at the offshore margin of the Pilbara Block called the Bedout Sub-basin. This sub-basin is believed to have had continued development during the Mesozoic with the accumulation of large thicknesses of Jurassic-Cretaceous sediments. It is restricted further offshore by the structurally positive Rankin Platform, a feature reflected in a large positive gravity anomaly.Mesozoic deposition was associated with a westerly tilt of the Rowley Shelf and Mesozoic thickness consequently increases westwards. The tilt increased during the Tertiary with the development of a major Tertiary stratigraphic wedge locally reaching 8000-10,000 feet in thickness at the shelf edge.Sedimentary deposition was controlled throughout Phanerozoic time by periodic epeirogenic warping related to uplift of the two major blocks. These movements caused considerable structural fragmentation and initiated periods of exiensive erosion. Complex lithofacies variations are thus expected and multiple intra-sectional unconformities are evident.The area contains many fault induced fold features, some compressional folds and extensive stratigraphic trap potential. Coarse clastic units with high hydrocarbon reservoir potential are expected to occur in close association with postulated marine Mesozoic basinal shale sequences. Similar deposits in the Carnarvon Basin and its offshore extension have been proved to be hydrocarbon bearing and productive (Barrow Island). The hydrocarbon potential of the offshore Canning Basin is thus rated highly.

Evolvement of interpretation capacities of seismic measurements in mining of water-soluble minerals

2021 ◽  
pp. 28-33
Author(s):  
I. A. Sanfirov ◽  
A. A. Zhikin ◽  
K. B. Fatkin ◽  
R. A. Bogdanov
Keyword(s):  
Rock Mass ◽  
Wave Field ◽  
Geophysical Methods ◽  
Structural Features ◽  
Water Soluble ◽  
Seismic Exploration ◽  
Seismic Surveys ◽  
Irregular Wave ◽  
Wide Range ◽  
Interval Velocities

The current development level of geophysical methods for mining monitoring of water-soluble mineral deposits provides opportunities to control the growing variety of potentially hazardous geological and mining conditions, to identify the critical states of rock mass and to monitor the emergency facilities. Seismic surveys for solving the specified problems have proven to be a highly informative method for studying the structural features and properties of productive and waterprotective overburden strata, which has a high information richness of the recorded data. The main set of parameters for the interpretation stage of seismic exploration has been formed based on the experience in shallow seismic surveys within a potash deposit; it incl udes the target reflection times, effective and interval velocities, amplitudes, frequencies and a number of derivatives from these parameters. Improvement and adaptation of world interpretation practices in relation to the indicated seismic studies conditions provides means for increasing reliability of anomalies identification and expanding the set of typical wave ‘images’ for various kinds of inhomogeneities in a wide range of wave field realizations and its attributes. The analysis of irregular wave field component in the results of scattered waves processing, spectral decomposition and RGB-mixing is considered as an additional techniques of qualitative interpretation. An approach is proposed to determining possible fracturing in rock mass based on the variability of interval velocities. In combination with the AVO-analysis, this approach makes it possible to assess the trend of rock disintegration within the emergency facilities. The interpretation results of the areal (quasi-3D) and spatial (3D) detailed surveys of a shallow potash deposit are presented.

Ultrastructural identification of three types of sensory setae on copepod antennae

1995 ◽  
Vol 53 ◽  
pp. 956-957
Author(s):  
T. M. Weatherby ◽  
P.H. Lenz
Keyword(s):  
Phase Locking ◽  
Membrane Surface ◽  
Reaction Times ◽  
High Sensitivity ◽  
Structural Features ◽  
Calanoid Copepods ◽  
Marine Food Webs ◽  
Dendritic Membrane ◽  
Ultrastructural Characterization

Crustaceans, as well as other arthropods, are covered with sensory setae and hairs, including mechanoand chemosensory sensillae with a ciliary origin. Calanoid copepods are small planktonic crustaceans forming a major link in marine food webs. In conjunction with behavioral and physiological studies of the antennae of calanoids, we undertook the ultrastructural characterization of sensory setae on the antennae of Pleuromamma xiphias.Distal mechanoreceptive setae exhibit exceptional behavioral and physiological performance characteristics: high sensitivity (<10 nm displacements), fast reaction times (<1 msec latency) and phase locking to high frequencies (1-2 kHz). Unusual structural features of the mechanoreceptors are likely to be related to their physiological sensitivity. These features include a large number (up to 3000) of microtubules in each sensory cell dendrite, arising from or anchored to electron dense rods associated with the ciliary basal body microtubule doublets. The microtubules are arranged in a regular array, with bridges between and within rows. These bundles of microtubules extend far into each mechanoreceptive seta and terminate in a staggered fashion along the dendritic membrane, contacting a large membrane surface area and providing a large potential site of mechanotransduction.

Rapid Online Buffer Exchange: A Method for Screening of Proteins, Protein Complexes, and Cell Lysates by Native Mass Spectrometry

2019 ◽  
Author(s):  
Zachary VanAernum ◽  
Florian Busch ◽  
Benjamin J. Jones ◽  
Mengxuan Jia ◽  
Zibo Chen ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
High Speed ◽  
Structural Information ◽  
Protein Complexes ◽  
High Sensitivity ◽  
Native Mass Spectrometry ◽  
Structural Features ◽  
Consumer Products ◽  
Cell Lysates ◽  
Protein Expression And Purification

It is important to assess the identity and purity of proteins and protein complexes during and after protein purification to ensure that samples are of sufficient quality for further biochemical and structural characterization, as well as for use in consumer products, chemical processes, and therapeutics. Native mass spectrometry (nMS) has become an important tool in protein analysis due to its ability to retain non-covalent interactions during measurements, making it possible to obtain protein structural information with high sensitivity and at high speed. Interferences from the presence of non-volatiles are typically alleviated by offline buffer exchange, which is timeconsuming and difficult to automate. We provide a protocol for rapid online buffer exchange (OBE) nMS to directly screen structural features of pre-purified proteins, protein complexes, or clarified cell lysates. Information obtained by OBE nMS can be used for fast (<5 min) quality control and can further guide protein expression and purification optimization.

scholarly journals Repression and Derepression of Minus-Strand Synthesis in a Plus-Strand RNA Virus Replicon

2004 ◽  
Vol 78 (14) ◽  
pp. 7619-7633 ◽  
Author(s):  
Guohua Zhang ◽  
Jiuchun Zhang ◽  
Anne E. Simon
Keyword(s):  
Solution Structure ◽  
Rna Virus ◽  
Structural Features ◽  
General Mechanism ◽  
Minus Strand ◽  
Turnip Crinkle Virus ◽  
Structural Elements ◽  
Transcription In Vitro

ABSTRACT Plus-strand viral RNAs contain sequences and structural elements that allow cognate RNA-dependent RNA polymerases (RdRp) to correctly initiate and transcribe asymmetric levels of plus and minus strands during RNA replication. cis-acting sequences involved in minus-strand synthesis, including promoters, enhancers, and, recently, transcriptional repressors (J. Pogany, M. R. Fabian, K. A. White, and P. D. Nagy, EMBO J. 22:5602-5611, 2003), have been identified for many viruses. A second example of a transcriptional repressor has been discovered in satC, a replicon associated with turnip crinkle virus. satC hairpin 5 (H5), located proximal to the core hairpin promoter, contains a large symmetrical internal loop (LSL) with sequence complementary to 3′-terminal bases. Deletion of satC 3′-terminal bases or alteration of the putative interacting bases enhanced transcription in vitro, while compensatory exchanges between the LSL and 3′ end restored near-normal transcription. Solution structure analysis indicated that substantial alteration of the satC H5 region occurs when the three 3′-terminal cytidylates are deleted. These results indicate that H5 functions to suppress synthesis of minus strands by sequestering the 3′ terminus from the RdRp. Alteration of a second sequence strongly repressed transcription in vitro and accumulation in vivo, suggesting that this sequence may function as a derepressor to free the 3′ end from interaction with H5. Hairpins with similar sequence and/or structural features that contain sequence complementary to 3′-terminal bases, as well as sequences that could function as derepressors, are located in similar regions in other carmoviruses, suggesting a general mechanism for controlling minus-strand synthesis in the genus.

Integrated geophysical modelling of terranes and other structural features along the western Canadian margin

1992 ◽  
Vol 29 (7) ◽  
pp. 1492-1508 ◽  
Author(s):  
S. A. Dehler ◽  
R. M. Clowes
Keyword(s):  
Seismic Refraction ◽  
Vancouver Island ◽  
Structural Features ◽  
Pacific Rim ◽  
Data Set ◽  
Reflection Seismic ◽  
Barkley Sound ◽  
The Pacific ◽  
Wrangellia Terrane ◽  
Lower Crustal

An integrated geophysical data set has been used to develop structural models across the continental margin west of Vancouver Island, Canada. A modern accretionary complex underlies the continental slope and shelf and rests against and below the allochthonous Crescent and Pacific Rim terranes. These terranes in turn abut against the pre-Tertiary Wrangellia terrane that constitutes most of the island. Gravity and magnetic anomaly data, constrained by seismic reflection, seismic refraction, and other data, were interpreted to determine the offshore positions of these terranes and related features. Iterative 2.5-dimensional forward models of anomaly profiles were stepped laterally along the margin to extend areal coverage over a 70 km wide swath oriented normal to the tectonic features. An average model was then developed to represent this part of the margin. The Pacific Rim terrane appears to be continuous and close to the coastline along the length of Vancouver Island, consistent with emplacement by strike-slip motion along the margin. The Westcoast fault, the boundary between the Pacific Rim and Wrangellia terranes, is interpreted to be 15 km farther seaward than in previous interpretations in the region of Barkley Sound. The Crescent terrane forms a thin landward-dipping slab along the southern half of the Vancouver Island margin, and cannot be confirmed along the northern part. Model results suggest the slab has buckled into an anticline beneath southern Vancouver Island and Juan de Fuca Strait, uplifting high-density lower crustal or upper mantle material close to the surface to produce the observed intense positive gravity anomaly. This geometry is consistent with emplacement of the Crescent terrane by oblique subduction.

Chondroitin sulfate and cytoplasmic domain-dependent membrane targeting of the NG2 proteoglycan promotes retraction fiber formation and cell polarization

2001 ◽  
Vol 114 (12) ◽  
pp. 2315-2325 ◽  
Author(s):  
William B. Stallcup ◽  
Kimberlee Dahlin-Huppe
Keyword(s):  
Chondroitin Sulfate ◽  
Rho Gtpase ◽  
Cytoplasmic Domain ◽  
Structural Features ◽  
Cell Polarization ◽  
Fiber Formation ◽  
Structural Elements ◽  
Motile Cells ◽  
Chondroitin Sulfate Chain ◽  
Ng2 Proteoglycan

Targeting of the NG2 proteoglycan to cellular retraction fibers was studied by expressing mutant NG2 molecules lacking specific structural elements of the proteoglycan. Both the cytoplasmic domain and the chondroitin sulfate chain of NG2 appear to have roles in sorting NG2 to subcellular microdomains destined to become retraction fibers. Neither of these structural features alone is sufficient to allow optimal targeting of NG2 to retraction fibers, but together they promote efficient localization of the proteoglycan to these sites. This pattern of NG2 sorting seems to be necessary for optimal retraction fiber formation, as cells expressing poorly targeted NG2 mutants are noticeably deficient in their ability to extend retraction fibers. Furthermore, retraction fiber formation correlates strongly with the tendency of cells to assume a polarized morphology with NG2-positive retraction fibers at one pole of the cell and actin-rich lamellipodia at the other. This polarization can be triggered either through engagement of NG2 by the substratum or by exposure to lysophosphatidic acid, a potent activator of the rho GTPase. These results suggest a possible role for NG2 in regulating rho-dependent mechanisms in the trailing processes of motile cells.

Aspect structural du Medoc atlantique

1960 ◽  
Vol S7-II (6) ◽  
pp. 796-800
Author(s):  
Michelle Caralp ◽  
M. Vigneaux
Keyword(s):  
Atlantic Coast ◽  
River Mouth ◽  
Structural Features ◽  
Structural Elements

Abstract Data from some 10 boreholes in the area south of the Gironde river mouth on the Atlantic coast of France show that there are three main structural elements below the Quaternary cover. From north to south, these are the Hourtin syncline, the faulted Carcans anticline, and the block-faulted section south of Carcans. These structural features controlled Tertiary deposition and, in particular, explain the lateral facies variations of Miocene formations.

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