Depositional Setting of the Triassic Dockum Group, Texas Panhandle Eastern New Mexico

The upper Triassic Dockum Group accumulated in relict Paleozoic basins defined in Texas by the Amarillo Uplift on the north and the Glass Mountains on the south. These basins were reactivated during the late Paleozoic or early Mesozoic by tectonic activity that was probably related to the opening of the Gulf of Mexico. As basins subsided and some relict positive elements were uplifted, sedimentation rates increased. More than 2,000 ft (610 m) of terrigenous elastics, derived chiefly from Paleozoic sedimentary rocks, accumulated within the basin. Source areas were in Texas, Oklahoma, and New Mexico; sediment transport was from the south, east, north, and west. The Dockum Group accumulated in a variety of depositional environments including: (1) braided and meandering streams; (2) alluvial fans and fan deltas; (3) distributary-type lacustrine deltas (high-constructive elongate deltas); (4) ephemeral and relatively long-lived lakes; and (5) mud flats. Alternation of wet and dry climate caused cyclic sedimentation in the Dockum. The main control on climate was most likely tectonism. During wet periods, lake level was relatively stable. Meandering streams supplied sediment to high-constructive elongate deltas in the central basin area of Texas and New Mexico, whereas braided streams and fan deltas were dominant depositional elements along southern and northern basin margins. Lake area and depth decreased when dry conditions prevailed. Under these conditions, base level was lowered, valleys were cut into older Dockum deposits, and small fan deltas were built into ephemeral lakes; evaporites, calcretes, silcretes, and soils developed upon emergent surfaces ranging from floors of ephemeral lakes to delta platforms.Bureau of Economic Geolog

Analisis Tingkat Seismisitas dan Tingkat Kerapuhan Batuan di Maluku Utara

ANALISIS TINGKAT SEISMISITAS DAN TINGKAT KERAPUHAN BATUAN DI MALUKU UTARA ABSTRAK Telah dilakukan penelitian untuk menentukan tingkat seismisitas dan tingkat kerapuhan batuan melalui perhitungan nilai a dan b secara spasial di Maluku Utara menggunakan katalog gempa ANSS tahun 1963-2015 dengan metode maksimum likelihood, menghitung kemungkinan waktu terjadinya kembali gempa bumi merusak secara spasial, serta untuk menenentukan daerah-daerah yang sangat rawan berpotensi gempa merusak di wilayah Maluku Utara. Perhitungan nilai a dan b dari data ANSS untuk wilayah Maluku Utara menunjukkan besar nilai b adalah berkisar pada 0,75-1,5 dan nilai a adalah berkisar pada 6,5-10. Periode ulang gempa bumi untuk wilayah Maluku Utara dengan magnitude Mw = 6,5 adalah 3-19 tahun, gempa dengan magnitude Mw = 7 adalah 5-52 tahun, dan gempa dengan magnitude Mw = 7,5 adalah 15-140 tahun. Daerah-daerah yang berpotensi mengalami gempa bumi merusak adalah wilayah Laut Maluku, Ternate, Tidore, sebagian wilayah Kabupaten Halmahera Utara dan Barat, Pulau Kasiruta dan Pulau Obi. Kata kunci: nilai-b, seismisitas, maximum likelihood ANALYSIS OF SEISMICITY LEVEL AND ROCKS FRAGILITY LEVEL IN NORTH MALUKU ABSTRACT A research has ben conducted to determine the seismicity level and rocks fragility level through spatially calculation of a value and b value in North Maluku using ANSS earthquake catalog of years 1963-2015 with maximum likelihood method, spatially calculate possible time of destructive earthquake recurrence, and to determine areas that highly prone to potentially destructive earthquake in North Maluku. A value and b value calculation of ANSS data of North Maluku region shows that b value is in the range of 0.75-1.5 and a value is in the range of 6.5-10. Earthquake repetition period of North Maluku region based on ANSS data with magnitude Mw = 6.5 is 3-19 years, for earthquake with magnitude Mw = 7 is 5-52 years and for earthquake with magnitude Mw = 7.5 is 15-140 years. Areas that potentially have destructive earthquake is Molucca Sea region, Ternate, Tidore, parts of North and West Halmahera District, Kasiruta Island and Obi Island

Consolidation of Geologic Studies of Geopressured-Geothermal Resources in Texas: Colocation of Heavy-Oil and Geothermal Resources in South Texas

In a five-county area of South Texas, geopressured-geothermal reservoirs in the Eocene Wilcox Group occur below heavy-oil reservoirs in the Eocene Jackson Group. This colocation warrants consideration of the use of geothermal fluids for a thermally enhanced waterflood. Geothermal fairways comprise thick deltaic sandstones within growth-fault-bounded compartments containing geopressured water in excess of 250°F. Geothermal reservoirs occur at depths of 11,000 to 15,000 ft in continuous sandstones 100 to 200 ft thick. Permeability ranges from 1 to 150 md, and porosity from 12 to 24 percent. Updip pinch-out of shallowly buried (200 to 2,000 ft) barrier-bar/strandplain sandstones largely controls the distribution of heavy-oil reservoirs. Subtle structure, small faults, and sandbody pinch-outs form lateral barriers of the reservoirs. Structural, depositional, and diagenetic variations affect reservoir compartmentalization. The heavy-oil reservoirs are typically porous (25 to 35 percent), permeable (100 to 1,000 md), slightly clayey fine to medium sand. Calcite-cemented zones of low porosity (>5 percent) and permeability (0.01 md) compartmentalize reservoirs. Injection of hot (300°F), moderately fresh to saline brines will improve oil recovery by lowering viscosity and decreasing residual oil saturation. Matrix clays are smectites, which could swell and clog pore throats if injected waters were fresh. The high temperature of injected fluids will collapse some of the interlayer clays, thus increasing porosity and permeability. Reservoir heterogeneity resulting from facies variation and diagenesis must be considered when siting production and injection wells within the heavy-oil reservoir. The suitability of abandoned gas wells as geothermal production wells and their long-term well productivity also affect the economics of geothermally enhanced hot-water flooding.Bureau of Economic Geolog

Identifikasi Patahan Manado dengan Menggunakan Metode Geolistrik Konfigurasi Wenner di Kota Manado

IDENTIFIKASI PATAHAN MANADO DENGAN MENGGUNAKAN METODE GEOLISTRIK KONFIGURASI WENNER DI KOTA MANADOABSTRAK Identifikasi keberadaan patahan Manado, Sulawesi Utara di Jalan Ringroad Kelurahan Malendeng Kecamatan Paaldua telah dilakukan penelitian menggunakan metode geolistrik tahanan jenis konfigurasi Wenner pada satu lokasi dengan dua lintasan pengukuran dengan panjang bentangan masing-masing 400 meter dengan spasi elektroda 20 meter. Data diolah dengan menggunakan software RES2DINV. Diperoleh hasil dari kedua lintasan dengan nilai resistivitas pada lintasan 1 bernilai (ρ < 311,5 Ωm) dan pada lintasan 2 nilai resistivitas bernilai (ρ < 98,8 Ωm). Nilai resistivitas dengan (ρ < 311,5 Ωm) pada lintasan 1, dan nilai resistivitas (ρ < 98,8 Ωm) pada lintasan 2 menunjukkan rekahan pada lintasan 1 terdapat pada titik bentangan ke 220-240 meter dengan kedalaman 37 meter dan terdapat pada titik ke 280-300 meter dengan kedalaman 15 meter. Sedangkan pada lintasan 2 rekahan terdapat pada titik ke 240-260 meter dengan kedalaman 15 meter. Kata Kunci : Patahan Manado, Metode geolistrik, Konfigurasi Wenner, Software RES2DINV. IDENTIFICATION OF MANADO FAULT BY USING GEOLECTRICAL METHOD RESISTIVITY CONFIGURATION OF WENNER AT MANADO ABSTRACT Identification of existence Manado fault, North Sulawesi at Ringroad Street, in Malendeng Village subdistrict Paaldua has been done research by using geoelectrical resistivity method configuration of Wenner in one located with measurement in two lines each others 400 meters in space electrode is 20 meters. Data processing is done by using RES2DINV software. resistivity value in the two lines show that for the first line (ρ 311,5 Ωm) and second line (ρ 98,8 Ωm). This resistivity in the first line (ρ 311,5 Ωm) and second line (ρ 98,8 Ωm) is founded already joint in first line at point 220-240 meters with depth is 37 meters and at point 280-300 meters with depth is 15 meters and second line position of joint stays at point 240-260 with depth is 15 meters

Analisis Medan Magnet Bumi Sebelum Dan Sesudah Kejadian Gempa (Studi Kasus: Gempa 18 November 2014 Di Sabang)

Telah dilakukan penelitian untuk mengidentifikasi dan menganalisis Perubahan medan magnet bumi sebelum dan sesudah kejadian gempa 18 November 2014 di Sabang yang dapat dikenali sebagai prekursor gempa bumi. Metode yang digunakan adalah perbandingan residu medan magnet komponen Z dan H. Untuk memastikan anomali yang diperoleh bukan berasal dari gangguan eksternal, data diverifikasi dengan Indeks Dst. Hasil yang diperoleh menunjukkan bahwa anomali medan magnet terjadi pada 2 dan 8 hari sebelum gempa. Anomali diduga kuat berasal dari aktivitas litosfer yang berkaitan dengan retakan yang terjadi pada batuan yang dialiri cairan yang mengandung material bersifat magnet yang menyebabkan kenaikan nilai rasio medan magnet Z/H.A research has been done to identify and analyze earth's magnetic field change before and after November 18th, 2014 earthquake in Sabang that can be recognize as an earthquake precursor. Method that used ini this research was comparison of Z and H residu of magnetic's field. To ensure that anomaly identified were not of due to external disturbances that records, data were examined by Dst Index. The result of this research showed that magnetic's field anomaly were identified in 2 and 8 days before earthquake event. This anomaly was predicted from lithosphere that associated with rock's crack that flow by liquid that contains magnetic material cause increased of magnetic's field Z/H rasio

Study of the physicochemical quality of water in the Sebi-Ponty basin at Diamniadio (Senegal)

The Sebi-Ponty dam has a basin that is widely used by the population for agro-pastoral activities (animal watering, agriculture, etc.). This basin covers an average area of 106,000 m2 and an average depth of 7 m or about a volume of 435,000 m3. The origin of the water is rainfall (runoff and direct descent). The availability of water is estimated to eight months taking into account the water being drawn, infiltration and evaporation. A qualitative knowledge of the contents of this pool will be a great benefit to those activities of the population. Itrsquos in this context that this study was carried out by this group of researchers, following physic-chemical compositions were targeted: turbidity, color, temperature, conductivity, pH, hardness alkalinity, nitrite, iron, phosphate, boron, and chlorine concentrations. The physico-chemical results obtained on samples taken in the basin between October and December showed that the concentrations of boron, iron and nitrite exceeded the levels recommended by the standard for agro pastoral needs. While turbidity, color, temperature, conductivity, pH, hardness, alkalinity, phosphate and chlorine are at acceptable levels

Consolidation of Geologic Studies of Geopressured-Geothermal Resources in Texas

In a five-county area of South Texas, geopressured-geothermal reservoirs in the upper Wilcox Group are colocated with heavy-oil reservoirs in the overlying Jackson Group. In 1990, research at the Bureau of Economic Geology concentrated on evaluating the potential of using geopressured-geothermal water for hot-water flooding of heavy-oil reservoirs. Favorable geothermal reservoirs are defined by thick deltaic sandstones and growth-fault-bounded compartments. Potential geothermal reservoirs are present at a depth of 11,000 ft (3,350 m) to 15,000 ft (4,570 m) and contain water at temperatures of 350°F (177°C) to 383°F (195°C) in Fandango field, Zapata County. One potential geothermal reservoir sandstone in the upper Wilcox (R sandstone) is composed of a continuous sand body 100 ft (30 m) to greater than 200 ft (>61 m) thick. Fault blocks average 2 to 4 mi^2 (5.2 to 10.4 km^2) in area. Both heavy-oil (average API=19) and light-oil (average API=26) reservoirs in South Texas are present in sandstones of the Jackson Group Mirando trend. The updip pinch-out of strike-oriented sheet sandstones in the Jackson Group largely controls the distribution of Mirando-trend heavy-oil reservoirs. The lateral continuity of heavy-oil reservoirs minimizes reservoir compartmentalization, which could disrupt injected-fluid flow paths. Geologic and engineering research that still needs to be conducted includes (1) studies of the chemical compatibility between injected geothermal fluids and clay matrix of heavy-oil reservoirs, (2) detailed field studies of geometry and size of geothermal reservoirs, (3) detailed field studies of geometry and size of heavy-oil reservoirs, and (4) studies of changes in the temperature and chemistry of geothermal fluids when injected into heavy-oil reservoirs.Bureau of Economic Geolog

Text Line Segmentation of Historical Documents: a Survey

There is a huge amount of historical documents in libraries and in various National Archives that have not been exploited electronically. Although automatic reading of complete pages remains, in most cases, a long-term objective, tasks such as word spotting, text/image alignment, authentication and extraction of specific fields are in use today. For all these tasks, a major step is document segmentation into text lines. Because of the low quality and the complexity of these documents (background noise, artifacts due to aging, interfering lines),automatic text line segmentation remains an open research field. The objective of this paper is to present a survey of existing methods, developed during the last decade, and dedicated to documents of historical interest.Comment: 25 pages, submitted version, To appear in International Journal on Document Analysis and Recognition, On line version available at http://www.springerlink.com/content/k2813176280456k3

External Ocular Surface Bacterial Isolates and their Antimicrobial Susceptibility Patterns among Pre-operative Cataract Patients at Mulago National Hospital in Kampala, Uganda.

Endophthalmitis is a severe complication of cataract surgery which leads to high ocular morbidity and visual loss even with antibiotic treatment. Bacterial ocular floras are the implicated causative agents. This study was undertaken to evaluate the external ocular surface bacterial isolates and their antimicrobial susceptibility patterns among pre-operative cataract patients at Mulago National Hospital. This cross sectional study enrolled consecutively 131 patients scheduled for routine cataract surgery in the Department of Ophthalmology at Mulago National Hospital in Kampala, Uganda. Eyelid margin and conjunctival swabs were collected and processed using standard microbiological procedures to identify bacterial isolates and their respective antimicrobial susceptibility patterns. Of 131 patients involved (mean age 63.3 ± 14.5 years), 54.2% (71/131) were females. The eyelid margin and conjunctival samples were culture positive in 59.5% (78/138) and 45.8% (60/138) respectively. The most common organisms identified were Coagulase-negative Staphylococci (CoNS) [65.9% (91/138)] and Staphylococcus aureus [21.0% (29/138)]. CoNS showed the highest resistance to tetracycline (58.2%, 53/91) and erythromycin (38.5%, 35/91), whereas in S. aureus the resistance to tetracycline and erythromycin were 55.2% (16/29) and 31.0% (9/29) respectively. Methicillin resistant CoNS (MRS) and Methicillin resistance S. aureus (MRSA) were 31.9% (29/91) and 27.6% (8/29) respectively. There were low resistance rates for CoNS, S. aureus and other bacterial isolates to ciprofloxacin (11.1%-24.2%), gentamicin (5.6-31.0%), tobramycin (17.2% -25.3%) and vancomycin (0.0%). CoNS and S. aureus are the most common bacterial isolates found on the external ocular surface of the pre-operative cataract patients. Ciprofloxacin, gentamicin, tobramycin and vancomycin showed the lowest resistance rates to all bacterial isolates, therefore may be used to reduce bacteria load in the conjunctiva sac among cataract patients prior to surgery

Molecular characterizations of the coagulase-negative staphylococci species causing urinary tract infection in Tanzania : a laboratory-based cross-sectional study

Funding: This study is part of the Holistic Approach to Unravel Antibacterial Resistance in East Africa (HATUA) project funded by the National Institute for Health Research, Medical Research Council and the Department of Health and Social Care, Award (MR/S004785/1).Background: There is a growing body of evidence on the potential involvement of coagulase-negative Staphylococci (CoNS) in causing urinary tract infections (UTIs). The aim of this study was to delineate virulence potential, antimicrobial resistance genes, and sequence types of CoNS isolated from patients with UTI symptoms and pyuria in Tanzania. Methods: CoNS from patients with UTI symptoms and more than 125 leucocytes/μL were retrieved, subcultured, and whole-genome sequenced. Results: Out of 65 CoNS isolates, 8 species of CoNS were identified; Staphylococcus haemolyticus, n = 27 (41.5%), and Staphylococcus epidermidis, n = 24 (36.9%), were predominant. The majority of S. haemolyticus were sequence type (ST) 30, with 8 new ST138-145 reported, while the majority of S. epidermidis were typed as ST490 with 7 new ST1184-1190 reported. Sixty isolates (92.3%) had either one or multiple antimicrobial resistance genes. The most frequently detected resistance genes were 53 (21%) dfrG, 32 (12.9%) blaZ, and 26 (10.5%) mecA genes conferring resistance to trimethoprim, penicillin, and methicillin, respectively. Out of 65 isolates, 59 (90.8%) had virulence genes associated with UTI, with a predominance of the icaC 47 (46.5%) and icaA 14 (13.9%) genes. Conclusion: S. haemolyticus and S. epidermidis harboring icaC, dfrG, blaZ, and mecA genes were the predominant CoNS causing UTI in Tanzania. Laboratories should carefully interpret the significant bacteriuria due to CoNS in relation to UTI symptoms and pyuria before labeling them as contaminants. Follow-up studies to document the outcome of the treated patients is needed to add more evidence that CoNS are UTI pathogens.Publisher PDFPeer reviewe