Extended-Time Conductivity Testing of Proppants Used for Multi-Stage Horizontal Completions

The American Petroleum Institute Recommended Practice 19-D (2018) is the current industry standard for conductivity testing of proppants used in hydraulic fracturing. Similar to previous standards from both the API and ISO, it continues the practice of measuring a "reference" long-term conductivity after 50-hours of time at a given stress. The fracture design engineer is then left to estimate a damage factor to apply over the life of the well completion based on correlations or experience. This study takes four standard proppants used for multi-stage horizontal well completions in North America and presents test data over 250-days of "extended-time" at 7,500 psi of effective stress. The API RP 19-D procedure was followed for all testing, but extended for 250-days duration for the four proppant types: 40/70 mesh mono-crystalline "White" sand, 40/70 mesh multi-crystalline "Brown" sand, 100 mesh "Brown" sand, and 40/70 mesh Light Weight Ceramic (LWC). The 7,500 psi stress condition was chosen to replicate initial stress conditions for a 10,000 feet deep well with a 0.75 psi/ft fracture gradient - typical of unconventional resource plays such as the Bakken formation of North Dakota or the Delaware Basin in west Texas. Results presented provide a measure of the amount of damage occurring in the proppant pack due to time at stress. To the authors’ knowledge, there has never been any extended-time conductivity data published for multiple proppant types over the timeframe completed in this study - despite the obvious need for this understanding to optimize the stimulation design over the full life of the well. Results for the four proppant types are presented as conductivity curves as a function of time for the 250-days of testing. Pack degradation is shown to follow a semi-log decline. Late time continued degradation for all materials is extrapolated over the life of a typical well (40 years), and compared to extended-time particle size distribution and crush data to explain the results observed. Extended-time data such as this 250-day study have never been published on proppants such as these despite the fact that fracture conductivity has a major impact on the productive life of a well and the ultimate recovery of hydrocarbons from the formation. The data presented should be of great interest to any engineer involved with completion designs, or reservoir engineers assessing the productive life and ultimate recovery in the formation since economic optimization is primarily driven by the interplay of fracture length/area with extended-time in-situ fracture conductivity.

Pengaruh Event Pariwisata dan Physical Evidence terhadap Keputusan Berkunjung

Indonesia is a maritime country, and it has more than thousands of beautiful islands. Those are the main reasons many domestic or even international tourists choose Indonesia for a holiday. White Sand Beach in Situbondo is one of the most visited tourist attractions. The local government that manages this place uses tourism events as a promotional medium and improves the physical evidence to attract more tourists to White Sand Beach for holidays. Therefore, this study aims to determine how effective tourism events and physical evidence influence the decision to visit this place. The survey was conducted using an online questionnaire and collected data from 50 early adult respondents who had visited the Beach. The data obtained were analyzed quantitatively through multiple linear regression analysis techniques in SPSS. This study shows that tourism events and physical evidence have a significant effect on visiting decisions. For further research, this study recommends comparing several different tourist attractions by adding variables and expanding the scope of respondents. The local government that manages the White Sand Beach tourism can use the findings as evaluation materials.

SPECIFIC MICROBIOLOGY SPECTRUM OF WHITE SAND MUSSELS FROM KEY SAMPLE SPOTS FROM BULGARIAN BLACK SEA AQUATORY

The "white sand mussels" are edible bivalves inhabiting the littoral shores usually buried in the sand. Тhey are invasive species for the Bulgarian waters of the Black Sea. The samples for this study were collected from different points on the northern and southern Black Sea Bulgarian coast in the period January 2020 to December 2020. The study of different types of microorganisms was performed by using the microbial identification system model: MicroLog M® BIO45101 BiologInc and the software product GEN III. The physic-chemical parameters of the waters – temperature, pH, salinity and dissolved O2 were also determined. In the different species, we had detected specific microbiological complexes. The species Pseudomonas viridilivida and Citrobacter farmer were isolated only from Donax trunculus. The species Escherichia hermannii was found only in Mya arenaria, and Acinetobacter johnsonii was detected only in Chamelea gallina. The isolated species Acinetobacter gyllenbergii and Acinetobacter johnsonii are related to humans and are indicators for pollution of the water with channel waste waters. Our results demonstrated an increase ofhe quantity of the coliforms the region of Sveti Vlas from August, where they were 50 the norms. In the region of Arkutino in July and Ahtopol in August, the quantity of the fecal coliforms is 190 and 30 times the norms prescribed in the Ordinanceo. 4 from 20.10.2000 for the quality of fisheries water and the breeding of shellfish (the amount of fecal coliforms in the inter-shell content should be less than 300 NVB). We noticed also seriousollution of the Varna lake even months after an accident with a leaky pipe.

Analisis Daya Dukung Kawasan Wisata Pantai Di Kecamatan Nambo Kota Kendari (Studi Kasus: Pantai Nambo)

Abstrak: Pariwisata adalah segala hal yang berhubungan dengan perjalanan untuk rekreasi, pelancongan, dan hiburan yang dilakukan dengan sukarela dan bersifat sementara serta didukung oleh berbagai fasilitas dan layanan yang disediakan oleh masyarakat, pengusaha, dan pemerintah daerah. Penelitian ini bertujuan untuk: (1) mengetahui kondisi lingkungan kegiatan pariwisata di Kecamatan Nambo; (2) mengetahui daya dukung lingkungan pariwisata Di Kecamatan Nambo. Metode dalam penelitian ini adalah metode penelitian kuantitatif. Metode penelitian kuantitatif digunakan untuk menjawab tujuan penelitian yaitu mengetahui kondisi lingkungan kegiatan pariwisata dan menganalisis daya dukung lingkungan pariwisata pantai di Kecamatan Nambo. Hasil penelitian menunjukkan bahwa: (1) Pantai Nambo merupakan Pantai yang terdiri dari pasir putih dengan topografi yang tidak curam,memiliki suasana yang tenang, udara yang dingin dan pemandangan yang indah. Pantai Nambo sendiri telah menyediakan fasilitas seperti tempat parkir, gazebo, tempat bilas mandi dan tempat sampah. Namun masih terdapat pengunjung yang membuang sampah sembarangan sehinggah mengotori lingkungan Pantai Nambo; (2) Berdasarkan perhitungan daya dukung lingkungan objek wisata Pantai Nambo, maka diperoleh nilai daya dukung fisik (PCC) atau jumlah maksimum wisatawan yang dapat diterima di area wisata dengan luas 10,3 ha sebesar 3.961 wisatawan/hari dengan nilai kapasitas manajemen (MC) sebesar 0,54 dan nilai daya dukung efektif (ECC) sebesar 2.138 wisatawan/hari dengan mempertimbangkan nilai PCC dan MC.Kata kunci: Analisis, Daya Dukung, Kawasan Wisata PantaiAbstract: Tourism is all things related to travel for recreation,travel, and entertainment which is carried out on a voluntary basis and is temporary andsupported by various facilities and services provided by the community,entrepreneurs, and local governments. This study aims to: (1) determine the conditionsthe environment of tourism activities in Nambo District, (2) know the carrying capacitytourism environment in Nambo district. The method in this research is quantitative research methods.Quantitative research method is used to answer objectivesresearch, namely knowing environmental conditions of tourism activities and analyzing carrying capacity of the coastal tourism environment in Nambo District.The results showed that: (1) Nambo Beach is a beach consisting of white sand with a topography that is not steep, has a calm atmosphere, cold air and beautiful scenery. Nambo Beach itself has provided facilities such as parking, gazebo, shower and trash cans. But there are still visitors who throw garbage carelessly so that they pollute the neighborhood of Nambo;(2) Based on the calculation of the environmental carrying capacity of the Nambo Beach tourist attraction,then obtained the value of the physical carrying capacity (PCC), the maximum number of touristswhich can be accepted in the tourist area with an area of 10.3 acre for 3,961 tourists/daywith a value of management capacity (MC) of 0.54 and an effective carrying capacity (ECC) of 2,138 tourists/day by considering the value of PCC and MC.Keywords: Analysis, Carrying Capacity, Beach Tourism Area

Collaborative and sustainable management strategy of the Wallacea Key biodiversity area (KBA) in Kasa Island

Kasa island, with an area of 52.80 Ha, was declared a KBA in the Wallacea region with the staut of wildlife sanctuary and Ocean Tourist Reserve because of its particular biodiversity and its service to the environment. This research aimed to determine the social, biophysical potential and the threats to the region, as well as to explore a collaborative management. The methods used included survey, spatial analysis of the vegetation and Focus Discussion Groups (FDG). The results showed a variety index level of 1.37%. The dominant tree species were belo hitam, salamuli daun besar and kayu besi pantai. The belo hitam species had the highest INP. The wildlife sanctuary is the habitat of the Gosong Maluku bird (Eulipoa and Megapodis), an endemic species called Gosong Maluku (Euliopa wallacei). Other species include Gosong Kelam (megapodius freycinet). The coastline with its white sand and natural ocean is a tourist attraction with development potential. The strategy which needs to be developed is by using strengths to take advantage of opportunities so they can overcome weaknesses and threats. the strategies developed are as follows: Collaborative Management; Strengthening The Capacity of Local Community and Formulation of regional policy regarding Kasa Island management

The Effect of Using White Sand As Material High Quality Concrete Mix

The use of concrete in Indonesia cannot be separated from skyscrapers, bridges with long spans, and underground buildings which generally have a larger load, so the use of high-strength concrete is necessary. This study aims to determine the value of compressive strength, split tensile strength, flexural strength, modulus of elasticity of concrete and determine the workability of fresh concrete with the addition of 0.8% superplaticizer. The test objects used in the form of cylinders with a diameter of 15 cm and a height of 30 cm as many as 15 pieces, and 3 pieces of blocks measuring 15 cm × 15 cm × 60 cm. From the results of the study, the compressive strength value was 43,007 MPa. The split tensile strength test is 3.584 MPa. The flexural strength test is 4,340 MPa. The elastic modulus test is 28447.956 MPa. From the slump test on fresh concrete with the addition of a superplaticizer, it is obtained by 10 cm.

Seagrass Vegetation Analysis in Jhembengan and Pasir Putih Beach, Bawean Island, East Java

Seagrass is a flowering plant that lives in coastal areas In Indonesia there are 12 species, where seagrasses are able to live at a depth of 1-90 meters, seagrass growth is influenced by several factors including the intensity of sunlight. The purpose of this study was to observe the cover, distribution, Importance Value Index (IVI) and correlation of abiotic factors with seagrass in Jhembangan Beach and White Sand on Bawean Island, East Java. The quadratic transect with 50 m length was used. Each station equipped with 3 transects with a distance of 25 m. The data collected includes the parameter of type, stand, and water quality. The data analyze use Past Program 3.15 systems. Three species of seagrass plant were collected. The total seagrass cover value was 32.6 percent at Jhembangan Beach, and 38 percent at Pasir Putih Beach. Clumped and uniform types were included in the distribution of seagrass at Jhembangan and Pasir Putih beach. The highest of important value index In Jhembangan and Pasir Putih was Thallasia hemprichii, while the association to abiotic factor such temperature, pH, salinity and DO variables are included in the good or perfect correlation with values range from 0.7 to 0.9.

Chemistry, Taxonomy and Ecology of the potentially chimpanzee-dispersed Vepris teva sp.nov. (Rutaceae) of coastal thicket in the Congo Republic

ABSTRACTContinuing a survey of the chemistry of species of the largely continental African genus Vepris, we investigate a species previously referred to as Vepris sp. 1 of Congo. From the leaves of Vepris sp. 1 we report six compounds. The compounds were three furoquinoline alkaloids, kokusaginine (1), maculine (2), and flindersiamine (3), two acridone alkaloids, arborinine (4)and 1-hydroxy-3-methoxy-10-methylacridone (5), and the triterpenoid, ß-amyrin (6). Compounds 1-4 are commonly isolated from other Vepris species, compound 5 has been reported before once, from Malagasy Vepris pilosa, while this is the first report of ß-amyrin from Vepris. This combination of compounds has never before been reported from any species of Vepris. We test the hypothesis that Vepris sp.1 is new to science and formally describe it as Vepris teva, unique in the genus in that the trifoliolate leaves are subsessile, with the median petiolule far exceeding the petiole in length. Similar fleshy-leathery 4-locular syncarpous fruits are otherwise only known in the genus in Vepris glaberrima (formerly the monotypic genus Oriciopsis Engl.), a potential sister species, but requiring further investigation to confirm this phylogenetic position. We briefly characterise the unusual and poorly documented Atlantic coast equatorial ecosystem, where Vepris teva is restricted to evergreen thicket on white sand, unusual in a genus usually confine to evergreen forest. This endemic-rich ecosystem with a unique amphibian as well as plants, extends along the coastline from the mouth of the Congo River to southern Rio Muni, a distance of about 1000 km, traversing five countries. We map and illustrate Vepris teva and assess its extinction risk as Endangered (EN B1ab(iii)+B2ab(iii)) using the IUCN standard. Only three locations are known, and threats include port and oil refinery construction and associated activities, with only one protected location, the Jane Goodall Institute’s Tchimpounga Reserve. Initial evidence indicates that the seeds of Vepris teva are dispersed by chimpanzees, previously unreported in the genus