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The pitch angle distributions of energetic Solar protons in the pseudo-trapping region were used in order to examine magnetospheric processes. Temporal and spatial variations of these processes should give insight into the magnetospheric dynamics. Data from two instruments (viewing angle perpendicular and 45° with respect to the local geomagnetic field) on board the low altitude polar orbiting satellite GRS/Azur give a rough measure of the pitch angle distribution of energetic Solar protons (1.5<E<2.7 MeV) over the polar cap. For several Solar particle events the ratios of the counting rates of the two instruments were ordered according to invariant latitude, magnetic local time and geomagnetic activity. The geomagnetic activity was expressed by the time phase relative to the expansion of isolated substorms and the H-component of the magnetic field at a near midnight auroral station. Thus the analysis shows substorm-related effects on energetic particles in the pseudo-trapping region.
ARK: https://n2t.net/ark:/88439/y019155
Permalink: https://geophysicsjournal.com/article/1
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The National Meteorological Archive is the official UK Place of Deposit for meteorological records. It is one of the many services provided by the Met Office. Records for England and Wales are held in our Exeter based repository; records for Scotland are stored in Edinburgh; and records for Northern Ireland are kept in Belfast. We also have records for overseas stations and hold the historic collections of the Royal Meteorological Society. The National Meteorological Archive is therefore home to one of the most comprehensive collections on meteorology anywhere in the world and provides a major resource for scientific and historical research of international scope. Our aim is to support the Met Office and the wider scientific community by providing a targeted, proactive and flexible information service; our primary role is to preserve the public memory of the weather and to conserve the records in our care.
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Records of the Geological Society of London, 1807-current, notably comprising: Minutes and papers of Annual General Meetings, 1840-current; minutes, correspondence and papers relating to meetings of the Council, 1810-current; minutes and papers of Ordinary Meetings, 1807-1998; minutes and papers of Special General Meetings; 1834-2001; Minutes and papers of Standing and Ad Hoc committees of Council, [1810]-current; Charter and Bye-laws, 1810-1993; Correspondence and other administrative papers relating to the running of the Geological Society, including: Presidents' Papers, 1977-1997; Elected Officers' papers, 1956-1995; Executive Secretary's papers, 1950-2013; Financial records, including bequests, trust funds, 1820-2011; Letterbooks of the Assistant Secretary and other Officers, [1807]-1960; Administrative records of departments, including: Membership, 1807-current; Conferences and scientific meetings, 1932-2006; Library, 1835-current; Archives and conservation, 1971-2004; Education Department, 1993-1998; Society's Museum, 1808-1911; Publications, 1906-2009; Portraits and photographs of Fellows, 1792-2011; Images of the interior and exterior of Burlington House, 1873-[1995]; Plans of the Society's apartments at Somerset House and Burlington House, 1828-[1982]; Obituaries & biographical information on Fellows, [1895]-current; Records of the Society's Centenary celebrations, 1907-1908; and Bicentenary celebrations, 1994-1998; Records of the Geological Society Club, 1824-2006; Records of the Society's Specialist Groups and Joint Associations, 1964-current.
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Records of the Institution of Geologists and its predecessors, 1973-1991, comprising: Minutes, papers, sample questionnaires, correspondence and reports of the Working Party on Professional Recognition, 1973-1975; Minutes, correspondence and papers of the Committee and sub committees of the Association for the Promotion of an Institution of Professional Geologists, 1975-1978; membership lists of the APIPG [incomplete], 1974-1977; documents relating to the incorporation of the APIPG as the Institution of Geologists, 1976-1977; draft rules and regulations of the proposed Institution of Geologists, 1977; Annual reports, agendas and other papers relating to the Annual General Meetings of the Institution of Geologists, 1978-1991; minutes and papers of the IG Council, 1977-1991; correspondence of the IG Council [incomplete], 1977-1984; correspondence and minutes of committees, sub committees, working groups and regional groups of the IG, 1977-1991; minutes, correspondence and papers of the joint Co-operation Committee, 1985-1991; annual accounts, 1977-1991; membership lists (incomplete), 1977-1986; rules and regulations, 1979-1986; correspondence, citations and speeches relating to the recipients of the Aberconway Medal, 1980-1989; obituaries, 1982-1985.
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The papers are principally biographical and research material. There are records of her career and honours, obituaries and letters of condolence (sent to John Sutton on her death), her own autobiographical notes, poems and short stories from the 1940s, and photographs including some from visits to East Germany in connection with the International Geological Correlation Programme. There is a sequence of thirty-six notebooks covering Watson's research, chiefly in the Scottish Highlands and Islands, from undergraduate research in 1946 to late work in Orkney during the early 1980s. Additionally a few notebooks record some of Watson's overseas visits. There are drafts and miscellaneous material relating to work in Scotland in the 1970s and a memoir on the geology of the Outer Hebrides compiled in collaboration with the Institute of Geological Sciences. Research is also represented by annotated maps.
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The public transportation system along the Kapuas River, Central Kalimantan are highly depend on water transportation. Natural condition gives high distribution to the smoothness of the vessel traffic along the Kapuas Murung River. The local government has planned to build specific port for stock pile at the Batanjung which would face with natural phenomena of sedimentation and erosion at a river mouth. Erosion and sedimentation could be predicted not only by field observing but it is also needed hypotheses using software analysis. Hydrodynamics and transport sediment models by Mike 21 HDFM-MT software will be applied to describe the position of sedimentations and erosions at a river mouth. Model is assumed by two different river conditions, wet and dry seasons. Based on two types of conditions the model would also describe the river flow and sediment transport at spring and neap periods. Tidal fluctuations and a river current as field observation data would be verified with the result of model simulations. Based on field observation and simulation results could be known the verification of tidal has an 89.74% correlation while the river current correlation has 43.6%. Moreover, based on the simulation the sediment patterns in flood period have a larger area than ebb period. Furthermore, the erosion patterns dominantly occur during wet and dry season within ebb period. Water depths and sediment patterns should be considered by the vessels that will use the navigation channel at a river mouth.
Keywords: Kapuas Murung River, software Mike 21 HDFM-MT, erosion and sedimentation pattern
Penduduk yang berada di sepanjang Sungai Kapuas sangat bergantung pada transportasi air. Kelancaran lalu lintas kapal di sepanjang Sungai Kapuas Murung sangat tergantung dengan kondisi alam yang terjadi. Rencana pemerintah daerah yang akan membangun pelabuhan khusus batubara di Batanjung akan berhadapan dengan fenomena alam yang umum terjadi di muara sungai yaitu sedimentasi dan erosi. Prediksi akan terjadinya sedimentasi dan erosi tidak hanya ditunjang pengamatan lapangan namun juga perlu dilakukan dengan melakukan hipotesa menggunakan bantuan analisis software. Penelitian ini akan menggambarkan posisi sedimentasi dan erosi di sekitar muara dengan pemodelan hidrodinamika dan transport sedimen yang menggunakan Software MIKE 21 HDFM-MT. Model dibuat dengan mengasumsikan kondisi sungai pada saat musim hujan dan musim kemarau. Berdasarkan dua kondisi tersebut model akan menggambarkan sebaran arus dan sebaran sedimen untuk periode bulan baru dan perbani. Data lapangan pasang surut dan kecepatan arus akan diverifikasi ke hasil simulasi model. Berdasarkan data hasil pengukuran lapangan dan data hasil simulasi model maka dapat diketahui bahwa verifikasi nilai pasang surut menunjukkan korelasi sebesar 89.74% sedangkan verifikasi nilai arus sebesar 43.6%. Selanjutnya dari hasil simulasi didapatkan bahwa pada saat pasang, gambaran posisi sedimentasi banyak terdapat pada bagian timur muara sungai dengan penyebaran cukup luas sedangkan pada kondisi surut area lebih sedikit. Selanjutnya gambaran daerah yang tererosi banyak terjadi pada saat air surut baik untuk musim hujan maupun kemarau. Kapal yang akan menggunakan muara sebagai alur pelayaran harus mempertimbangkan kondisi kedalaman air yang ada dan juga pola sedimentasi yang terjadi.
Kata kunci: Sungai Kapuas Murung, software Mike 21FM HD-MT, erosi dan pola sedimentasi
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According to the regulation No 4 of 2009 of Mineral and Coal Mining Management stated that the requirement of an inventory for mineral resources data was created to support the establishment of mining area. This study is intended to obtain mineral resources content and surficial sediment data, Geographically the study area belongs to Meranti Archipelago Regency, Riau Province. it is located between 102o00'00" - 103o 15'00" E and 00o35'00" - 01o28'00" N. Grain size analyses result show that surficial sediment in the study area consists of silt, silty sand and sand which is dominated by silt. Based on the mineral identification, some of the minerals such as quartz, cassiterite, magnetite, hematite, dolonite, biotite and zircon have been found. Silt distribution is very wide started from estuarine southeast part northen part of Rangsang Island toward southeast of rangsang island. Sandy silt only found at the southeast of Rangsang Island, while sand sediment is found at the south and southeast of Rangsang Island. The presence of silt and sand grains is influenced by moderate to strong currents and wave patterns, so that the silt and sand grains sediment was transported along coastal to offsore area, while the fine grained (clay - silt) are deposited in the valley at the western part of Rangsang Island.Keywords: mineral, surficial sediment, Rangsang Island Berdasarkan Undang Undang Nomor 4 tahun 2009 tentang Pengelolaan Pertambangan Mineral dan Batubara, disebutkan bahwa inventarisasi data sumber daya mineral diperlukan dalam rangka mendukung penetapan Wilayah Pertambangan (WP). Penelitian ini dimaksudkan untuk memperoleh data kandungan sumber daya mineral dan sedimen dasar laut. Daerah penelitian, secara geografis termasuk dalam Kabupaten Kepulauan Meranti, Provinsi Riau, dan terletak pada koordinat antara 102o00'00" - 103o15'00" BT dan 00o35'00" - 01o28'00" LU. Hasil analisis besar butir menunjukkan sedimen permukaan dasar laut di daerah penelitian terdiri atas lanau, lanau pasiran dan pasir yang didominasi oleh lanau. Berdasarkan identifikasi mineral pada sedimen permukaan dasar lautnya menunjukkan kehadiran mineral kasiterit, magnetit, hematit, dolomit, biotit, zirkon dan kuarsa. Penyebaran lanau sangat luas dimulai dari daerah estuari barat laut dan bagian utara Pulau Rangsang, hingga ke sebelah tenggara Pulau Rangsang. Lanau pasiran hanya terdapat di tenggara Pulau rangsang, sedangkan pasir hanya terdapat di daerah di bagian selatan - tenggara Pulau Rangsang. Adanya butiran lanau - pasir dipengaruhi oleh pola arus dan gelombang yang sedang sampai kuat, sehingga butiran berukuran lanau - pasir dapat terangkut ke arah lepas pantai, sedangkan butiran halus (lempung) mengendap di daerah lembah di bagian barat Pulau Rangsang. Kata kunci: mineral, sedimen permukaan dasar laut, Pulau Rangsang
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Arafura Sea is located between Papua and Australia as a part of Sahul Shelf. It is strongly influenced by ITF, ITCZ replacement, monsoon, and ENSO circulation that interplay with local mechanism. To understand the paleoceanographic parameter changes during Holocene, we conducted foraminiferal quantitative analysis from a 152 cm length sediment core (Aru–07), in every 10 cm interval. This sediment core was retrieved from 134o00’33.6” E, 5o55’51.59” S, by RV Geomarin 3 belongs to Marine Geological Institute. Geochronology of the sediment was reconstructed based on 2 AMS 14C age dates, analyzed on organic samples. We identified 129 species of benthic and 24 species of planktonic foraminifera that is dominated by planktonic specimens with average of 53.14%. Predominant species are Globigerina bulloides (16.16%), Globigerinoides ruber (11.18%), and Neogloboquadrina dutertrei (5.65%). Benthic type is dominated by genera Bolivina, Bulimina, and Uvigerina by 25.86% (average). This might suggest eutrophic condition associated with carbon-rich or low oxygen level (dysoxic) condition. Single linkage cluster analysis revealed 3 paleoenvironmental zones, are: Zone I: older than 3.9 kyr BP, characterized by depleted oxygen level and nutrient enrichment compared to that of younger zone. Zone II: 3.9 – 2 kyr BP, characterized by oxygen content enrichment and deeper thermocline layer, related to the sea level rise during more neutral or La Niña like condition. Zone III: younger than 2 kyr BP, represent shallower thermocline layer, higher productivity which might be related to upwelling, and dysoxic condition. Sea level might be declined that related to more El Niño like condition.Keywords: Paleoceanographic changes, upwelling, foraminiferal analysis, Arafura SeaLaut Arafura berlokasi di antara Papua dan Australia sebagai bagian dari Paparan Sahul. Kondisi iklim sangat dipengaruhi oleh ITF, perpindahan ITCZ, monsun, dan ENSO yang berinteraksi dengan mekanisme lokal. Untuk memahami perubahan parameter oseanografi selama Holosen, kami melakukan analisis kuantitatif mikrofauna foraminifera, yang dilakukan terhadap sebuah bor sedimen laut sepanjang 152 cm (Aru–07) pada interval setiap 10 cm. Bor sedimen bawah laut ini telah diambil pada posisi 134o00’33.6” BT, 5o55’51.59” LS, menggunakan kapal penelitian Geomarin 3, Pusat Penelitian Geologi Kelautan. Geokronologi sedimen berdasarkan 2 radiocarbon dating, dianalisis dari sampel organik pada sedimen. Teridentifikasi 129 spesies bentik dan 24 spesies plangtonik yang didominasi oleh plangtonik dengan persentase rata-rata 53.14%. Foraminifera Jenis–jenis yang dominan antara lain Globigerina bulloides (16.16%), Globigerinoides ruber (11.18%), dan Neogloboquadrina dutertrei (5.65%). Sedangkan jenis bentik didominasi oleh genus Bolivina, Bulimina, dan Uvigerina, dengan persentase rata–rata 25.86%. Hal tersebut kemungkinan menunjukkan kondisi eutropik yang berasosiasi dengan kondisi kaya karbon dan rendah level oksigen (disoxic). Analisis cluster single linkage menunjukkan tiga zona utama, yaitu: Zona I: lebih tua dari 3.9 kyr BP, dicirikan oleh relatif rendahnya kandungan oksigen dan lebih kaya kandungan nutrien. Zona II: 3.9 – 2 kyr BP, dicirikan oleh meningkatnya kandungan oksigen, dan mendalamnya lapisan termoklin, berkaitan dengan meningkatnya muka air laut ketika kondisi netral atau kondisi seperti La Niña. Zona III: lebih muda dari 2 kyr BP, merupakan zona dengan kondisi lapisan termoklin yang mendangkal, produktifitas meningkat yang kemungkinan berkaitan dengan upwelling, dan kondisi disoxic. Muka air laut kemungkinan turun, berasosiasi dengan kondisi seperti El Niño.Kata kunci: Perubahan paleoseanografi, upwelling, analisis foraminifera, Laut Arafura
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The identification of quality and condition of the coral reef in the study areas will support the biological diversity and it frequently contains a valuable assortment of natural resources, conservation of marine biota. The environmental problem particularly on the coastal area needs a more comprehensive management due to the complexity of the rapidly growth. Karimata Archipelago geographically is located between 108o40' - 109o10' E and 1o25' - 1o50' S and administratively belongs to the Ketapang Regency (approximate 100 km west side of Ketapang). In the study area, the growth of coral reef is dominated by non-Acropora type arised between the depths 3-15m. The condition is somewhat good to good. Karimata Archipelago consist of two big islands they are Karimata Island (Studied area) and Serutu Island and also some other isles, with the topography from low land to high land having the height of about 1030 meters from sea level.
Keywords: Coral reef, Karimata coast, West Kalimantan.
Identifikasi kualitas dan kondisi terumbu karang di daerah penelitian dapat menopang keanekaragaman biologi yang pada akhirnya dapat berperan sebagai kawasan konservasi biota laut. Masalah kepekaan lingkungan khususnya di wilayah pantai dan pesisir memerlukan penanganan yang lebih komperhensif, karena kawasan ini relatif lebih kompleks selain perkembangannya yang demikian pesat. Gugusan kepulauan Karimata secara geografi menempati posisi 108o40' - 109o10' BT and 1o25' - 1o50' LS dan secara administrasi masuk dalam Kabupaten Ketapang (lebih-kurang berjarak 100 km ke arah barat dari Ketapang). Di lokasi telitian, keberadaan terumbu karangnya didominasi oleh jenis non-Acropora yang tumbuh baik pada kedalaman antara 3 hingga 15 m. Terumbu karang yang dijumpai dengan kondisi agak baik hingga baik. Kepulauan Karimata terdiri dari 2 pulau besar, P. Karimata di mana lokasi studi terletak dan P.Serutu dan beberapa pulau-pulau kecil dengan topografi dari dataran rendah hingga dataran tinggi (1030 m) di atas permukaan laut.
Kata kunci:Terumbu karang, Pantai Karimata, Kalimantan Barat.
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Study area is located in South Banda Basin near the triple junction between Eurasian, Pacific and Indo-Australian Plates. This area is part of back-arc thrusting zone that evolved to compensate convergence between Australia Continent and Banda Arc. Based on seismic section in this area, geological structure analysis is characterized into three distinctive zones. There are Thrust Zone (TZ), Proto Thrust Zone (PTZ) and Normal Fault Zone (NFZ). TZ is defined by distribution of numerous of thrust fault, PTZ contains a blind zone or folds instead of thrust fault, and NFZ defined by distribution of numerous normal fault in the upper portion of seismic section. PTZ identified at several seismic section along the bending zone of oceanic crust. The appearances of bending zone will be easily understood by comprehend the driving mechanism of Australia Continent to the Northeast. The bending zone also related to geometry and tectonic stress of collision. Based on this mechanism it was clearly understood why the western end of study area was not identified the bending zone but it probably the initial process of bending. Contradictive to the western end, the eastern part was clearly shown the bending zone that assumed to have the biggest tectonic stress at this moment. Map of structural analysis also explain that PTZ getting narrow towards the west as the indicator of less of tectonic stress.Keywords: Arc-Continent Collision, Proto Thrust Zone, Wetar, Back arc Thrusting, Banda Sea. Lokasi penelitian berada pada Cekungan Banda Selatan sekitar area triple junction antara Lempeng Eurasia, Pasifik dan Indo-Australia.Daerah ini merupakan bagian dari zona back-arc thrusting yang berkembang sebagai kompensasi dari konvergensi antara kontinen Austalia dan Busur Banda.Berdasarkan penampang seismik di daerah ini analisis struktur geologi dikelompokan kedalam tiga zona. Tiga zona tersebut meliputi Thrust Zone (TZ), Proto Thrust Zone (PTZ) and Normal Fault Zone (NFZ). TZ didefinisikan oleh distribusi dari sejumlah sesar naik, PTZ mengandung sejumlah blind thrust atau lipatan pengganti sesar naik dan NFZ didefinisikan oleh distribusi dari sejumlah sesar normal pada bagian atas dari penampang seismik. PTZ teridentifikasi pada beberapa penampang seismic sepanjang zona bending dari lempeng oseanik. Kenampakan dari zona bending akan mudah dipahami dengan mengetahui mekanisme pergerakan dari kontinen Australia ke arah timurlaut. Zona ini umumnya berhubungan dengan bentuk geometri dan besaran dari tectonic stress dari tumbukan. Berdasarkan mekanisme ini dapat dipahami dengan jelas mengapa bagian ujung barat dari daerah penelitian tidak teridentifikasi zona bending. Kontradiktif terhadap ujung barat, ujung timur memperlihatkan zona bending yang sangat jelas yang diperkirakan mempunyai tectonic stress yang paling besar pada saat ini. Peta dari analisis struktur juga menjelaskan bahwa zona PTZ semakin ke arah barat semakin menyempit sebagai indicator dari berkurangnya tectonic stress.Kata Kunci: Tumbukan Busur-Kontinen, Proto Thrust Zone, Wetar, Back arc Thrusting, Banda Sea.
