DOCSLIB.ORG

Tidal Propagation in the Gulf of Carpentaria Are Developed

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Tidal Propagation in the Gulf of Carpentaria Are Developed tolrol¿Õ i TIDAL PROPAGATION IN THE GULF OF CARPENTARIA by Michele Marie Rienecker B.Sc. (ttons. ), University of Queensland Thesis submitted for the degree of Doctor of PhilosoPhy in the University of Adelaide Department of Applied Mathematics December L978 tli" 1-qT0 [^t.ro{r.i 11ì 0,q J TABLE OF CONTENTS SUMMARY (i) SIGNED STATEMENT ( ii) ACKNOIIILEDGEMENTS (íii) CHAPTER 1 INTRODUCTION I CHAPTER 2 THE PROBLEM: A RECTÆ{GULAR RESONATOR ON A SEMI-INFINITE CHANNEL 2.L The Tidal Equations 5 2.2 Frequency Response Analysis 6 2.3 Reformulation of the Equations for an Analytic Model 8 CHAPTER 3 THE ANA],YTIC SOLUTION 3.1 The Method of Solution and the Boundary Conditions 10 3.2 Solution for the Channel Region 11 3.3 Solution for the ResonaÈor Region 13 3.4 Solution folthe Junction Region 15 3.5 The Remaining Matchíng Conditions and the Galerkin Technique 20 CHAPTER 4 AN EXTENSION TO THE MODEL: AN ADJOINING CHANNEL 4.1 The Equatíons 35 4,2 The Solutions 37 4.3 Determination of ô 46 CHAPTER 5 TI4IO NUMERICAL MODELS 47 5.1 A Linear Fínite-oifference Numeríca1 Model 4B 5,2 The EVP Method 52 5.3 Stability, Consistency and Convergence 55 5.4 The Friction Parameter 59 5.5 A Non-Linear Model 6L 5.6 Consistency, Convergence and Stability 64 CHAPTER 6 APPLICATION TO TIIE GI]LF OF CARPENTARIA 6.1 The Gulf of CarPentaría 68 6.2 The AnalYtic Model of ChaPter 3 72 6.3 The AnalYtic Model of ChaPter 4 89 6.4 The Linear Numerical Model 95 6.5 The Non-linear Numerical Model 105 6.6 The Programs 110 6.7 The Response of the Gulf to Tidal Forcing 110 116 CHAPTER 7 CONCLUSION 1t_8 APPENDIX 1 The Representation of Bottom Friction L27 APPENDIX 2 \te Galerkin and Collocation Methods APPENDIX 3 Evaluation of the Integral Form for 6z(x,y) 130 APPENDIX 4 The Classes of Elements for the Non-linear Model and Their Associated Finite-Difference Equations 135 138 BIBLIOGRAPHY (i) SUMMARY This thesis considers tidal propagation in a rectangular resonator-channel system, with specific reference to the Gulf of Carpentaria, situated to Èhe North of Australia. The linearízed form of the trdo-dimensional depth-averaged equations of continuity and momenEum conservation is used. An analytic solution is found by dividing the area into regions of constant deprh. In this manner, a solution is found for Èhe case of a síngle connecting channel and then for the exEended case of two connecting channels, associated with either neglecÈing or including the effect of tidal flux from Torres Strait into the Gulf. Results from the analytic model are used to provide tidal inputs for two numerical models, both of which use explicir finite- difference approximations. The first numerical model is linear and is developed to account for realistic boundary and bathynetry variations, with the emphasis on obtaining a model with small- compuÈer time and memory requirements. Since, in shallower coastal areas, the non- linear Lerms in Èhe continuity and momentum equations become more important, the second numerical model developed includes these terms to determíne their effect on the resonator as a whole. The two models show favourable agreement, thus verifying the usefulness of the linear mode 1 . ( ii) SIGNED STATEMENT I hereby declare that this thesis contains no material which has been accepted for the award of any other degree or diploma in any University and, to the best of my knowledge, it contains no material previously published by any other person, except where due reference ís made in the text of the thesie. M.M. RIENECKER. (iii) ACKNOI,üLEDGEMENTS I would like to thank my st¡pervisor, Dr. B.J. Noye, for his advice and guidance in completíng this thesis. Many thanks are also due Èo Dr. Michael Teubner for his help and encouragement throughout, Èo Mrs. Angela McKay for her excellent, accurate typing, to Mr, G. de Vries for preparing the diagrams and to Mr. Phil Leppard for his advice on computing. The work associated wíth this thesis was carried Òut from February 1975 to November 1978, during which time I was financed by a Commonwealth Postgtaduate Research Award' M.M. Rietrecker - 1 CHAPTER 1 INTRODUCTION The Gulf of Carpentaria, located in tl're North-Eastern part of Australia, is an area of difficult access by either land or water and hence remains relatively uncharted and unstudied. However, over the past few years, there has been an increase in the nuirber of research programs in the area as its potential for the lucrative rnining and fishing industries has been recognized. Lirnited sectors, such as at lrleipa, PorÈ McArthur, Groote Eylandt and Gove Peninsular, have been surveyed as port facilities l{ere required by mining companies. The C.S.I.R.O. has reported on the hydrology of the region (Rochford (1966), Newell (1973)) and has made a preliminary study of the circulation in the Gulf (Cresswell (1971)). Further work by this organízatíoa is currently under way. The Gulf r^ras also chosen by Teleki et al (1973), as the test site for assessing the usefulness of satellite irnagery to the rnapping of hydrological parameters in areas of difficult access. Tides and wind are the only two mechanisms which generate Èhe currenÈs in the atea. For several months of the year it is the influence of the strong, sÈeady trade winds which drive the circulation. However, overall, the circulation and mixing of waters ín the Gulf are governed by the clockwise motíon of tides and by density gradients resulting from the stratification of the water masses. Stratification is partly induced by differential evaporation rates betvreen the Northern and Southern halves of the bay (Teleki et al (1973)). According to Newell (1973), "the annual evaporatiorr/precipitation budget of Èhe Gulf forms a very sma1l part of ?- the total water exchange but is of great importance in influencing water movement.tt One examPle of the effect, in the Gulf, of winds and precipitation/ evaporation is the striking feature of the annual cycle of about .7m rn the tides, the lowesttídes being r:ecorded at the end of the drl' season and the highest during the wet season' It is during the wet season, which occurs in the summer months, that the activity of cyclones sometimes has a disastrous effect, causing large surges. some description of this is given by Easton (1970) who outlines the general tidal features of the Gulf. Realistic and accurate modelling of the waÈer movement in the Gulf of Carpentaria is obviously an intricate affair, it being necessary to incorporate the effects of tide, wind, stratification, precipitation/ evaporation and Pressure surges, not to mention ríver run-off and sediment transport. However, whereas the effects of the other mechanisms diminish at certain times of the year, Eidal forcing is always Present; and it is only the response of the Gulf to tidal forcing which is investigated in this thesis. Once the Èi-dal response is understood, it is easier to sËudy the coupling of the tide with other effsu[s' The tides are caused by the movement of the sun and the moon and their changing gravitational pull on the $Iater of the earth; however, in coastal areas, such as gulfs and estuaries, a\¡Iay from the deep oceans, astronomical tidal forcing can usually be neglected compared to the direct forcing from the motion of adjacent r¡raters. From the results of Hamblin (1976) for different size basins, the maximum amplitude of the resPonse of the Gulf of Carpentaría to direct astronomical forcing could be expected to be only about 3 cm, a very sma1l contribution to the response as a whole In this thesis, Eidal propagation in Gulf systems is investigated by finding the resPonse of Ëhe system Èo tidal forcing on an open boundary' 3 One of Èhe main problems in ascertaining the accuracy or limitations of any model of an area is that reliable input data across the open boundary is rarely available, especially if the boundary is wide. Data is usually available from coastal areas, but this may be disturbed by local effects and is not always representative for the open sea. Values may be inter- polated between coastal areas, but this does not normally take into account the disÈribution of depth (see Hansen (1962)). A more accurate input may be obtained from the results of an analytic model which produces the input from the solution to the model equations. This still does not account for the true distribution of depth, but avoids the need to interpolate over wide areas. Analytic models have their limiEations in that they provide solutions only for simplified situations; however, they can be very useful in providing an insight into the important feaÈures of a model area. As well as providing the tidal forcing daÈa along an open boundary for numerical models, they may also act as a guideline to the accuracy or validity of these more complicated models. lüith this in mind, two analytic models of the tidal propagation in the Gulf of Carpentaria are developed. They a, e essentially extensions of Taylorrs (I92Oa) problem of the reflection of a Kelvin wave by an end barrier in a semi-infinite channel. tr{illiams (L972) modelled the Gulf as a rectangular resonator on a serni-infinite channel. His first model neglects the effect of the Coriolis force; his second considers the frequency of rotation of the earEh to be small compared to the frequency of the tidal motion. The models in this thesis are extensions of his work, incorporating, amongst other things, the dissipation of energy by bottom friction.
Load more

Recommended publications
  • GEOG 101 PLACE NAME LIST for EXAM THREE
    GEOG 101 PLACE NAME LIST for EXAM THREE Each exam will have a place name location map section based on the list below, plus countries and political units. Consult the appropriate maps in the atlas and textbook to locate these places. The atlas has a detailed INDEX. Exam III will focus on place names from Asia and Oceania. This section of the exam will be in the form of a matching question. You will match the names to numbers on a map. ________________________________________________________________________________ I. CONTINENTS Australia Asia ________________________________________________________________________________ II. OCEANS Pacific Indian Arctic ________________________________________________________________________________ III. ASIA Seas/Gulfs/Bays/Lakes: Caspian Sea Sea of Japan Arabian Sea South China Sea Red Sea Aral Sea Lake Baikal East China Sea Bering Sea Persian Gulf Bay of Bengal Sea of Okhotsk ________________________________________________________________________________ Islands: New Guinea Taiwan Sri Lanka Singapore Maldives Sakhalin Sumatra Borneo Java Honshu Philippines Luzon Mindanao Cyprus Hokkaido ________________________________________________________________________________ Straits/Canals: Str. of Malacca Bosporas Dardanelles Suez Canal Str. of Hormuz ________________________________________________________________________________ Rivers: Huang Yangtze Tigris Euphrates Amur Ob Mekong Indus Ganges Brahmaputra Lena _______________________________________________________________________________ Mountains, Plateaus,
    [Show full text]
  • Geog 120: World Geography American University of Phnom Penh
    Geog 120: World Geography American University of Phnom Penh Map Quizzes: List of physical features 1. Africa Atlas Drakensberg Seas and Oceans Deserts Mediterranean Atlantic Kalahari Strait of Gibraltar Namib Suez Canal Sahara Mozambique Channel Ogaden Red Sea Libyan Gulf of Suez 2. Asia Lakes Lake Chad Seas and Oceans Lake Malawi (Nyasa) Lake Tanganyika Andaman Sea Lake Victoria Arabian Sea Lake Albert Aral Sea Lake Rudolph Arctic Ocean Atlantic Ocean Rivers Black Sea Caspian Sea Congo East China Sea Limpopo Indian Ocean Niger Inland Sea (also know as Setonaikai, Zambezi Japan) Nile Mediterranean Sea Orange Pacific Ocean Vaal Red Sea Sea of Japan Mountains Sea of Okhotsk 2 South China Sea Mountain Ranges Yellow Sea Caucuses Elburz Straits, Channels, Bays and Gulfs Himalayas Hindu Kush Bay of Bengal Ural Bosporus Zagros Dardanelles Gulf of Aden Gulf of Suez Deserts Gulf of Thailand Arabian Gulf of Tonkin Dasht-E-Kavir Persian Gulf Gobi Strait of Taiwan Negev Strait of Malacca Takla Makan Strait of Hormuz Strait of Sunda Suez Canal 3. The Americas Lakes Seas and Oceans Baykal Bering Tonle Sap Caribbean Sea Atlantic Ocean Pacific Ocean Rivers Straits, Channels, Bays and Gulfs Amur Brahmaputra Gulf of Mexico Chang Jiang Hudson Bay Euphrates Panama Canal Ganges Strait of Magellan Huang He (Yellow) Indus Lakes Irrawaddy Mekong Great Salt Tigris Great Lakes (Lakes Tonle Sap (River and Lake) Superior, Michigan, Huron, 3 Erie, and Ontario) 4. Australia and the Pacific Manitoba Titicaca Winnipeg Seas and Oceans Coral Sea Rivers Tasman Sea Pacific Ocean Amazon Indian Ocean Colorado Columbia Hudson Straits, Channels, Bays and Gulfs Mississippi Bass Strait Missouri Cook Strait Ohio Gulf of Carpentaria Orinoco Torres Strait Paraguay Plata Parana Rivers Rio Grande Darling St.
    [Show full text]
  • Morning Glories" ^S'as* Over Northern Australia And
    Interacting "Morning Glories" ^S'aS* over Northern Australia and Abstract some of the place names mentioned in the text is displayed in Fig. 1a; the remaining place names are It is just over 15 years since the first major expedition was indicated on Fig. 1b, which focuses on the Gulf of organized to investigate the "morning glory" phenomenon of north- Carpentaria region.) A photograph of a morning glory eastern Australia. The authors review briefly what has been learned roll cloud is shown in Fig. 2. The clouds are parallel to about the generation and evolution of morning glory disturbances during this time and present data for a particularly interesting event one another, often stretching for several hundred that occurred on 3 October 1991, a day on which two morning glory kilometers. The leading roll is usually smooth, whereas wave formations, one from the northeast and one from the south, were successive rolls are more ragged in texture reflecting detected. The morning glories were seen to interact over the Gulf of a higher degree of turbulence. As the name suggests, Carpentaria. Spectacular National Oceanic and Atmospheric Ad- ministration/Advanced Very High Resolution Radiometer satellite imagery together with comparatively good surface data are pre- sented for this event. Aspects of the interaction between the north- easterly and southerly morning glories are shown to be consistent with theoretical predictions concerning solitary wave interactions. 1. Introduction Solitary waves are isolated finite-amplitude waves of permanent form. Although their mathematical prop- erties have been studied for the past century and a half, only recently have they been viewed as funda- mentally important in the evolution of a wide variety of dynamical systems in the physical and biological sciences.
    [Show full text]
  • Revisiting Inscriptions on the Investigator Tree on Sweers Island, Gulf of Carpentaria
    REVISITING INSCRIPTIONS ON THE INVESTIGATOR TREE ON SWEERS ISLAND, GULF OF CARPENTARIA COLLINS, S. J.1, MATE, G.2,1 & ULM, S.1,3 The Investigator Tree, so named after Matthew Flinders’ ship HMS Investigator, is an inscribed tree currently on display in the Queensland Museum. Before being accessioned into the Queensland Museum’s collection in 1889, the Investigator Tree grew on the western shore of Sweers Island in the southern Gulf of Carpentaria. The tree’s “Investigator” inscription, attributed to Flinders (1802), provided the catalyst for future and varied forms of European inscription making on Sweers Island, including a contentious additional “Investigator” inscription on the Investigator Tree carved by Thomas Baines in 1856. Previous researchers have speculated that Baines’ second “Investigator” inscription has caused the faded original “Investigator” inscription to be misinterpreted as either a Chinese or Dutch inscription predating Flinders’ visit to Sweers Island. For the first time, this study undertakes a physical examination of all markings on the Investigator Tree, including a second portion of the tree located at the Queensland Museum since 2009. In com­ bination with a review of the archival and historical record, findings provide alternative interpretations regarding the (28) inscriptions to address outstanding questions. Archival documents demonstrate that there were at least three inscribed trees on Sweers Island. This paper also revisits the possibility of there once being pre­Flinders inscriptions on the Investigator
    [Show full text]
  • Northern Large Marine Domain
    Collation and Analysis of Oceanographic Datasets for National Marine Bioregionalisation: The Northern Large Marine Domain. A report to the Australian Government, National Oceans Office. May 2005 CSIRO Marine Research Peter Rothlisberg Scott Condie Donna Hayes Brian Griffiths Steve Edgar Jeff Dunn Cover Image designed by Vincent Lyne CSIRO Marine Researchi Cover Design Lea Crosswell and Louise Bell CSIRO Marine Research Collation and Analysis of Oceanographic Datasets – The Northern Large Marine Domain Contents Contents...........................................................................................................................................i List of Figures.................................................................................................................................ii 1. Summary................................................................................................................................1 2. Project Objectives..................................................................................................................2 3. Background............................................................................................................................2 4. Data Storage and Metadata....................................................................................................2 5 Setting for the Northern Large Marine Domain ....................................................................3 5.1 Geomorphology..............................................................................................................4
    [Show full text]
  • REY Patterns and Their Natural Anomalies in Waters and Brines: the Correlation of Gd and Y Anomalies
    hydrology Article REY Patterns and Their Natural Anomalies in Waters and Brines: The Correlation of Gd and Y Anomalies Peter Möller * , Peter Dulski and Marco De Lucia GFZ German Research Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany; [email protected] (P.D.); [email protected] (M.D.L.) * Correspondence: [email protected] Abstract: Rare earths and yttrium (REY) distribution patterns of the hydrosphere reveal system- atic correlations of Gd and Y anomalies besides the non-correlated redox-dependent Ce and Eu anomalies. Eu anomalies are inherited by dissolution of feldspars in igneous rocks, whereas Ce, Gd and Y anomalies develop in aqueous systems in contact with minerals and amorphous matter. Natural, positive Gd and Y anomalies in REY patterns characterize high-salinity fluids from the Dead Sea, Israel/Jordan, the Great Salt Lake, USA, the Aral Sea, Kazakhstan/Uzbekistan, ground- and surface water worldwide. Extreme Gd anomalies mostly originate from anthropogenic sources. The correlation of Gd and Y anomalies at low temperature in water bodies differ from geothermal ones. In nature, dynamic systems prevail in which either solids settle in water columns or water moves through permeable sediments or sedimentary rocks. In both cases, the anomalies in water develop due to repeated equilibration with solid matter. Thus, these anomalies provide information about the hydrological history of seawater, fresh groundwater and continental brines. When migrating, the interaction of aqueous phases with mineral surfaces leads to increasing anomalies because the Citation: Möller, P.; Dulski, P.; more hydrophillic Gd and Y preferentially remain in the aqueous phase compared to their nearest De Lucia, M.
    [Show full text]
  • Gulf of Carpentaria
    newsletter of australian wildlife conservancy wildlife matters SUMMER 2008/09 An historic partnership to save the wildlife of the Gulf of Carpentaria Terry Trewin P. Rothlisberg S. Murphy Lochman Transparencies a u s t r a l i a n w i l d l i f e saving australia’s conservancy threatened wildlife the awc mission Pictograph The mission of Australian Wildlife elcome to the Summer 2008 edition of Wildlife Matters. At a time when global financial Conservancy (AWC) is the effective Wmarkets are in turmoil, I am pleased to provide some very good news about one of your conservation of all Australian animal investments. Australian Wildlife Conservancy (AWC) continues to deliver very strong positive returns. species and the habitats in which they Of course, the value of our assets is not measured in dollars but in terms of the number of native live. To achieve this mission, our actions wildlife species and habitats that are effectively conserved on AWC sanctuaries. In this respect, are focused on: AWC is a market leader, protecting more species of birds, mammals, reptiles and amphibians, and their habitats, than any other non-government organisation in Australia. • Establishing a network of sanctuaries Over the last 12 months, we have increased the number of species and habitats that are which protect threatened wildlife and protected by AWC through the acquisition of key sanctuaries in central and northern Australia. ecosystems: AWC now manages 20 However, most importantly, we have continued to deliver effective conservation for species on sanctuaries covering over 2.5 million our sanctuaries through the implementation of practical, on-ground programs targeting feral hectares (6.2 million acres).
    [Show full text]
  • Gulf of Carpentaria Line Fishery (GOCLF) Is a Multi-Species Fishery Which Predominately Targets Spanish Mackerel (Scomberomorus Commerson) Using Surface Troll Lines
    Queensland the Smart State Annual status report 2008 GulfEast Coastof Carpentaria Spanish MackerelLine Fishery Fishery The Department of Primary Industries and Fisheries (DPI&F) seeks to maximise the economic potential of Queensland’s primary industries on a sustainable basis. While every care has been taken in preparing this publication, the State of Queensland accepts no responsibility for decisions or actions taken as a result of any data, information, statement or advice, expressed or implied, contained in this report. © The State of Queensland, Department of Primary Industries and Fisheries 2008. Copyright protects this material. Except as permitted by the Copyright Act 1968 (Cth), reproduction by any means (photocopying, electronic, mechanical, recording or otherwise), making available online, electronic transmission or other publication of this material is prohibited without the prior written permission of the Department of Primary Industries and Fisheries, Queensland. Inquiries should be addressed to: Intellectual Property and Commercialisation Unit Department of Primary Industries and Fisheries GPO Box 46 Brisbane Qld 4001 or [email protected] Tel: +61 7 3404 6999 Introduction The Gulf of Carpentaria Line Fishery (GOCLF) is a multi-species fishery which predominately targets Spanish mackerel (Scomberomorus commerson) using surface troll lines. Other permitted species typically comprise only a small portion of the overall catch. Permitted species encompass a variety of pelagic (living in open ocean) and demersel (bottom-dwelling) groups. Pelagic groups include trevally and the lesser mackerels that are caught via trolling methods. Demersel groups frequenting coral and rocky reef areas include tropical snappers, cods and emperors, and are primarily caught in waters between 10 and 30 m deep using hand lines (Roelofs, 2004).
    [Show full text]
  • Twelve Tropical Sea Treasures
    Twelve Tropical Sea Treasures Underwater Icons of Northern Australia Underwater Icons of Northern Australia Cobourg Pinnacles 4 Van Diemen Rise 3 • Darwin Fog Bay 2 1 Joseph Bonaparte Gulf • Wyndham • Derby 1 Joseph Bonaparte Gulf – huge tides, sea snakes and red-legged banana prawns 2 Fog Bay – flatback turtles, seabirds and critically endangered sawfish 3 Van Diemen Rise – carbonate banks, olive ridley turtles and coral reef cafes for sharks 4 Cobourg Pinnacles – ancient reef remnants, light-loving marine life, leatherback turtles 5 Arafura Canyons – deepwater upwellings, whale sharks and special red snapper 6 Arnhem Shelf Islands – clear waters, endemic species and underwater sacred sites 5 Arafura Canyons Cobourg Pinnacles 12 Torres Strait Arnhem Shelf Islands 6 7 Northern Gulf • Nhulunbuy • Darwin • Weipa 11 Central Gulf/ 8 Groote Cape York Joseph Bonaparte Gulf 9 Limmen Bight 10 Southern Gulf • Karumba 7 Northern Gulf – traditional knowledge and contemporary science 8 Groote – rare snubfin dolphins and sea turtles 9 Limmen Bight – seagrass meadows, dugong haven 10 Southern Gulf – fresh waters, wild rivers and phytoplankton 11 Central Gulf/Cape York – soft bottoms, heart urchins and a clockwise current 12 Torres Strait – sea turtle highway Our northern tropical seas Northern Australians love getting out on the water. tropical marine life that is threatened with extinction in A quarter of Territorians own a boat. We fish, sail, other parts of the world. It is the good health of these kayak, and even swim and snorkel in our waters waters and the abundant (but threatened) sea life they when the season is right and the water is safe.
    [Show full text]
  • The Northern Planning Area (PDF – 3.79
    Atlas - Northern Chapter 3 The Northern Planning Area Planning is now underway in the Northern Planning Area (figure 2). The Northern Planning Area covers about 800 000 km2 of water off the Northern Territory and Queensland coasts, and includes the Torres Strait, the Gulf of Carpentaria Fisheries Uses and Social Indicators in Australia’s Marine Jurisdiction and eastern Arafura Sea (to a line 133°23’ east, which coincides with the Goulburn Islands). Maps in this Atlas are of the Northern Planning Area. The Northern Planning Area covers a significant proportion of the Northern Marine Region. The Northern Planning Area is a region of great diversity in its land and sea scapes, its biodiversity and its people. It is an area of rich Indigenous cultural diversity but with a sparse population, located chiefly in isolated communities. Its main industries are fishing and mining, but compared with much of Australia’s marine domain, it is economically largely undeveloped. Marine planning in the Torres Strait is being considered as part of a separate process and was not covered by the arrangements agreed between the Queensland and Australian Governments for scoping the northern marine planning process. This is in recognition of the distinct ecological, cultural and institutional arrangements that characterise the Torres Strait. Figure 2: Indicative map of the Northern Planning Area 6 > Chapter 3 7 > Chapter 3 Atlas - Northern Map 1A - The Northern Planning Area Satellite Overview MODIS satellite imagery mosaic. NASA Earth Observatory. 135°E 140°E 145°E Indonesia This map uses a mosaic of data from the MODIS Papua New Guinea (Moderate Resolution Imaging Spectroradiometer) sensor aboard the Earth Observer System satellites operated by NASA.
    [Show full text]
  • Pilot Investigation of the Origins and Pathways of Marine Debris Found in the Northern Australian Marine Environment
    SUMMARY Pilot investigation of the origins and pathways of marine debris found in the northern Australian marine environment Introduction Every year hundreds of lost or abandoned fishing nets are found along parts of the northern Australian coastline, especially areas of the Gulf of Carpentaria. To find out where these derelict nets come from, and the paths they may drift to reach the coast, a pilot project was commissioned. The project involved the use of a computer model and floating satellite transmitters to predict the likely pathways of these derelict nets in waters north and east of Australia. The pilot project found that derelict nets entering the Gulf of Carpentaria could originate in the South Pacific and Coral Sea (off Australia’s east coast), before being blown through the Torres Strait during the dry season by the south-east trade winds. This document provides a non-technical summary of the full technical report of the pilot project undertaken by Dr David Griffin (CSIRO, Centre for Australian Weather and Climate Research), entitled ‘Pilot investigation of the origins and pathways of marine debris found in the northern Australian marine environment’ http://www.environment.gov.au/coasts/publications/index.html). Project background Marine debris is a growing global problem that many nations are trying to address. Fishing nets that have been lost accidentally or deliberately abandoned at sea are a particularly concerning component of this marine debris, because of the navigational hazards they pose and the number of marine creatures that they harm and kill as they drift through the oceans with the currents and tides.
    [Show full text]
  • Queensland Geological Framework
    Geological framework (Compiled by I.W. Withnall & L.C. Cranfield) The geological framework outlined here provides a basic overview of the geology of Queensland and draws particularly on work completed by Geoscience Australia and the Geological Survey of Queensland. Queensland contains mineralisation in rocks as old as Proterozoic (~1880Ma) and in Holocene sediments, with world-class mineral deposits as diverse as Proterozoic sediment-hosted base metals and Holocene age dune silica sand. Potential exists for significant mineral discoveries in a range of deposit styles, particularly from exploration under Mesozoic age shallow sedimentary cover fringing prospective older terranes. The geology of Queensland is divided into three main structural divisions: the Proterozoic North Australian Craton in the north-west and north, the Paleozoic–Mesozoic Tasman Orogen (including the intracratonic Permian to Triassic Bowen and Galilee Basins) in the east, and overlapping Mesozoic rocks of the Great Australian Basin (Figure 1). The structural framework of Queensland has recently been revised in conjunction with production of a new 1:2 million-scale geological map of Queensland (Geological Survey of Queensland, 2012), and also the volume on the geology of Queensland (Withnall & others, 2013). In some cases the divisions have been renamed. Because updating of records in the Mineral Occurrence database—and therefore the data sheets that accompany this product—has not been completed, the old nomenclature as shown in Figure 1 is retained here, but the changes are indicated in the discussion below. North Australian Craton Proterozoic rocks crop out in north-west Queensland in the Mount Isa Province as well as the McArthur and South Nicholson Basins and in the north as the Etheridge Province in the Georgetown, Yambo and Coen Inliers and Savannah Province in the Coen Inlier.
    [Show full text]