Large-scale Drilling Research Articles

Preliminary Investigation into Measurement While Drilling as a Means to Characterize the Coalmine Roof

The variable nature of the coalmine roof poses a challenge to roadway stability during underground coal mining. There have been fatalities and financial losses in the coal mining industry due to roadway failures and roof falls. Generally, the geotechnical and geological data gathered from exploration boreholes, which are drilled at considerable distances from each other, are used to characterize the thickness and quality (including strength) of the coalmine roof. This process provides a limited number of samples that cannot represent the discontinuous nature of the strata in the coalmine roof nor can they form reliable inputs to a digital model of the rock mass component of the digital mine. Gaining confidence in the strata properties of the coalmine roof is necessary for the modelling, design, and maintenance of roadways. The paper describes the progress of the ongoing work to investigate the monitoring while drilling (MWD) concept for characterizing coalmine roofs. Large-scale drilling experiments in synthesized sandwiched rock samples without interfaces were carried out. The drilling response data were analyzed to identify whether the drill data differentiates the various strengths associated with the rock samples. The initial results show that the drilling data can differentiate the synthesized rock samples.

The Role of Japan DMAT in Tokyo Inland Earthquake

Introduction:An inland earthquake is expected to occur in Tokyo in the near future, and disaster preparedness and response measures have been put in place by the government of Japan and local authorities.Methods:Japan Disaster Medical Assistant Teams (DMATs) conducted two large-scale drills for the first time in preparation for a Tokyo inland earthquake, in collaboration with the following participants: the Tokyo Metropolitan Government, disaster base hospitals in Tokyo, three Staging Care Units (SCUs), and neighboring prefectures. One of the scenarios was a north Tokyo Bay earthquake affecting the Tokyo wards and had 142 Japan DMATs participation. Another scenario was Tama inland earthquake affected mid-west of Tokyo and 110 DMATs participated. The drill included headquarters operation, affected hospital support operation, patient transportation within the area and to the wider region, SCU operation, collaboration with associated organizations, and logistics operation.Results:Post-drill assessments identified the following areas that need to be addressed: review of Japan DMAT implementation strategies; improvement of SCUs; establishment of a patient air transportation framework; securing means of patient transportation; improvement of communication systems; strengthening of disaster response of all hospitals in the Tokyo Metropolis; and preparations for survival in the event of isolation caused by the disaster.

An Analysis of the Physical Mechanics Characteristics of a High-stacked Tailings Dam

From construction to operation, tailings have to go through a long period of time. With the passage of time, the early deposited tailings are gradually covered by the later deposited tailings, and the overburden on the accumulated tailings gradually increases. The different deposition time of tailings dam and the physical and mechanical characteristics of tailings in the sedimentary area are quite different, especially for high-stacked tailings dam. Therefore, it is very important to study the variation of physical and mechanical characteristics in the tailings of high-stacked tailings. In this paper, according to the early, middle and late operational stages, from 1989 to 2005, large scale drilling, in-situ testing and indoor testing were carried out on a certain upstream high pile tailings dam with a maximum thickness of 60m, 100m, and 125m. The physical and mechanical indexes of tailings were divided according to the time and place of deposition, in order to find out the changing laws of physical and mechanical characteristics of the tailings sand around 16 years ago. According to the changing law of the physical and mechanical characteristics of tailings, this paper puts forward the statistical tailings parameters according to the different deposition time and location of tailings, the research results provide reference for choosing the calculating parameters in designing and analyzing tailings dams. Its research results have been applied in the protection of the tailings dam, the tailings reservoir environment protection, and the safety hidden danger management of tailings reservoirs.

Hollow-Core Microstructured Optical Fiber Gas Sensors

Recent progress in gas detection with hollow-core microstructured optical fibers (HC-MOFs) and direct absorption/photothermal interferometry spectroscopy are reported. For direct-absorption sensors, the issue of mode interference noise is addressed and techniques to minimize such a noise are experimentally demonstrated. Large-scale drilling of hundreds of low-loss micro-channels along a single HC-MOF is performed, and reduction of diffusion-limited response time from hours to ∼40 s is demonstrated with a 2.3-m-long HC-MOF. For photothermal inteferometry sensors, novel detection configurations based on respectively a Sagnac interferometer and an in-fiber modal interferometer are experimentally demonstrated. The Sagnac configuration avoids the need for complex servo-control for interferometer stabilization while the in-fiber configuration simplifies the detection, reducing the size and cost of the sensor system. Sub ppm gas detection can be achieved easily with photothermal interferometry HC-MOF sensors but is difficult to achieve for direct-absorption sensors with the current commercial HC-MOFs.

(A233) Preparedness For A Mega Mass-Casualty Event (MMCE)

A Mega Mass-Casualty Event (MMCE) is a unique and exceptional event, that results in a very large number of casualties (500–5000) needing emergency care in the prehospital and hospital settings. This type of event usually goes beyond the capabilities of a certain region and requires reinforcement of resources from adjacent and remote regions. Due to its exceptional nature, a MMCE dictates a different organization of all emergency services and agencies involved. As a result of the recent experience, and in order to adequately prepare for such future events, a novel MMCE doctrine was developed by a committee of diverse emergency professionals. This doctrine was transferred to guidelines referring to MMCE recognition and the following series of actions that need to taken at all levels. It holds organizational, operational, and clinical aspects, as well as command and control elements. In November 2009, a large-scale drill of 1,000 mock casualties was performed in order to validate and evaluate the MMCE plan. This drill emphasized the need for the involvement of all pertinent emergency services and agencies, and their optimal collaboration and coordination, subjected to regional and national headquarters' command and control. In addition, the need for dedicated educational programs and o-going training was recognized. It was accepted that adequate planning is obligatory for better outcomes in the future.

Towing Resistance Calculation of the Cylindrical Drilling Platform

Towing the large-scale drilling platform without self-propulsion is difficult. Towing resistance calculation is necessary for safe pilotage. The tug power decision and the fleet arrangement should be confirmed according to the features and performance of towed vessel, water flow, air flow and other meteorological factors in towing route. The resistance calculations of towed vessel and tugboats are carried out. Whether it is suitable to be towed by the fleet will be verified in accordance with the calculations of the hauling power of tugboats. In this paper, the towing resistance of the cylindrical ultra-deep drilling platform without self-propulsion capability is studied, which could provide reference for other cylindrical structures on the implementation of towing plans.

Geology and mineralogy of ore at the hidden Engteri Au-Ag deposit, the Magadan Region

The Engteri is a new hidden Au-Ag deposit in the Russian segment of the Pacific ore belt. The discovery of this deposit merits special attention, because it involves repeated attempts to reappraise a lowprospective ore occurrence, which were crowned with success as a result of fulfillment of large-scale drilling project. The average Au grade is 18.6 gpt. The deposit is classified as the gold geochemical type of Au-Ag deposits. The major ore mineral is pyrite, which amounts to no less than 95% of the total ore minerals. The native phases comprise electrum and to a lesser extent native gold of low fineness (730). The homogenization temperature of fluid inclusions is 125–255°C with a distinct maximum at 145–150°C. Despite blind localization of some orebodies, the Engteri deposits bears evidence for a deep erosion level: (1) small vertical range of economic mineralization (50–100 m); (2) predominant occurrence of massive sugarlike quartz with a low sulfide content; (3) prevalence of massive and brecciated textures above rhythmically banded textures; and (4) lack of low-temperature propylites. The southern part of the ore field distinguished by occurrence of rhythmically banded, framework-tabular, and brecciated texture has the best prospect for revealing new orebodies. The Engteri deposit allowed us to outline the following prospecting guides and methods of prospecting for hidden Au-Ag deposits: (1) these deposits are regularly arranged in ore clusters between heavy concentrate anomalies of cinnabar and gold-silver or silver-base-metal occurrences (method of missed link); (2) findings of fragments of ore mineral assemblages with sporadically high Au and Ag contents in barren calcite-quartz veins (method of indicators); (3) linear zones of ankeritization in the fields of low- and mediumtemperature propylites (mapping of metasomatic rocks); and (4) pyrite-quartz veinlets with rhythmically banded pockets (mineralogical mapping of halos of stringer-disseminated mineralization).

Reunification: Keeping Families Together in Crisis

In reviewing the literature, there has not been a family reunification plan that has worked consistently during disasters. During Hurricane Katrina, there were children who were sent to a shelter in a different state than their patients. When children are involved, the issues become even more difficult, because some children who are preverbal cannot tell their names or their parents names. Tracking systems have been developed but are not interoperable. No central repository has been developed. There are also issues related to transporting patients, psychosocial issues as well as safety issues that are different when children will be unaccompanied by an adult. Two national meetings were held with experts from all over the country who have an expertise in the care of children. Six focused groups were identified: patient movement/transportation; technology/tracking; clinical issues, nonmedical issues; communication/regulatory issues; and pediatric psychosocial support. The second meeting was a consensus conference. Recommendations from each subgroup were presented and voted on. All recommendations were accepted. The issue of reunification of families in disaster is still a problem. Further work needs to be done on tracking systems that are interoperable before another large disaster strike, pediatric psychological issues after a disaster, transporting patients, and care of the pediatric patient who is not accompanied by an adult. Once a system has been developed, the system needs to be tested by large scale drills that practice moving children across state lines and from one area to another.

Model for Preparedness of a Public Institution for a Terrorist Attack

Public institutions such as governmental facilities, hospitals, universities, and amusement parks may be targeted by terrorists using weapons of mass destruction due to their potential to cause large numbers of casualties. Consequentially, these institutions should be prepared to manage such an event by the development and implementation of specific preparedness guidelines for any conventional or unconventional terrorist attacks. In order to test the preparedness of such an institution for a chemical event, a large-scale drill focusing on the first medical team to respond was conducted. Some important lessons regarding the way the medical team operates and communicates were learned from this drill. Periodic drills should be performed in order to assess the practicality and applicability of these guidelines.

Who Should Worry for the “Worried Well”? Analysis of Mild Casualties Center Drills in Non-Conventional Scenarios

A mass toxicological event (MTE) caused by an act of terrorism or an industrial incident can create large numbers of ambulatory casualties suffering from mild intoxication, acute stress reaction (ASR), and exacerbation of chronic diseases or iatrogenic insult (such as atropine overdose). The logistical and medical management of this population may present a challenge in such a scenario. The aim of this article is to describe the concept of the Israeli Home Front Command (HFC) of a "Mild Casualties Center" (MCC) for a chemical scenario, and to analyze the results of two large-scale drills that have been used to evaluate this concept. Two large-scale drills were conducted. One MCC drill was located in a school building and the second MCC drill was located in a basketball stadium. These medical centers were staffed by physicians, nurses, and medics, both military (reservists) and civilian (community, non-hospital teams). Two hundred simulated patients entered the MCC during each of the drills, and drill observers assessed how these patients were managed for two hours. Of the casualties, 28 were treated in the "medical treatment site", 10 of which were relocated to a nearby hospital. Only four casualties were treated in the large "mental care site", planned for a much higher burden of "worried well" patients. Documentation of patient data and medical care was sub-optimal. A MCC is a logistically suitable solution for the challenge of managing thousands of ambulatory casualties. The knowledge of the medical team must be bolstered, as most are unfamiliar with both nerve gas poisoning and with ASR. Mild casualties centers should not be located within hospitals and must be staffed by non-hospital, medical personnel to achieve the main task of allowing hospital teams to focus on providing medical care to the moderate and severe nerve gas casualties, without the extra burden of caring for thousands of mild casualties.

Impact Excavation and the Search for Subsurface Life on Mars

Because of the ubiquity of subsurface microbial life on Earth, examination of the subsurface of Mars could provide an answer to the question of whether microorganisms exist or ever existed on that planet. Impact craters provide a natural mechanism for accessing the deep substrate of Mars and exploring its exobiological potential. Based on equations that relate impact crater diameters to excavation depth we estimate the observed crater diameters that are required to prospect to given depths in the martian subsurface and we relate these depths to observed microbiological phenomena in the terrestrial subsurface. Simple craters can be used to examine material to a depth of ∼270 m. Complex craters can be used to reach greater depths, with craters of diameters ≥300 km required to reach depths of 6 km or greater, which represent the limit of the terrestrial deep subsurface biosphere. Examination of the ejecta blankets of craters between 17.5 and 260 km in diameter would provide insights into whether there is an extant, or whether there is evidence of an extinct, deep subsurface microbiota between 500 and 5000 m prior to committing to large-scale drilling efforts. At depths <500 m some crater excavations are likely to be more important than others from an exobiological point of view. We discuss examples of impacts into putative intracrater paleolacustrine sediments and regions associated with hydrothermal activity. We compare these depths to the characteristics of subsurface life on Earth and the fossil microbiological record in terrestrial impact craters.

Core drilling of the basin-fill sediments in the Kathmandu Valley for palaeoclimatic study: preliminary results

Core drillings in ancient lake sediments of the Kathmandu Valley, central Nepal Himalaya were carried out in order to clarify the past Indian monsoon climate and its linkage to the uplift of the Himalaya. This is the first large-scale drilling project in the valley with full core recovery, and solely dedicated to academic research purpose. The drilling penetrated the whole sequence of 208 m thick Kalimati Clay, newly defined as the Kalimati Formation.&#x0D; Based on the drill-core study, the sediments are divided into three formations: 1) Bagmati Formation, 2) Kalimati Formation, and 3) Patan Formation in ascending order. These formations have very distinct sedimentary characteristics: Bagmati essentially gravelly, Kalimati clayey and Patan sandy. The lower part of the Kalimati Formation, showing marginal lake facies, has been designated as the Basal Lignite Member. Judging from the lithology and sedimentary facies and previous studies on the Lukundol Formation, the Bagmati Formation is interpreted to have been deposited by the Proto-Bagmati River prior to the appearance of the lake before 2 Ma. The clay-predominant Kalimati Formation lying over the Lignite Member was deposited in an open lacustrine environment, which is mainly composed of carbonaceous clay yielding abundant fossil leaves and diatomaceous laminite. The fluvial sand of the Patan Formation rests on the Kalimati clay bed with a marked erosional base. The 14C age of the uppermost part of-the Kalimati Formation suggests that the lake water of the Kathmandu Basin was drained out later than 10 kyr B. P. (Fujii and Sakai 2002). Based on comparison of the present altitude of the ancient lake floor and top set beds of the lacustrine delta sediments (dated as 29 kyr B.P.), the water-depth of the Palaeo-Kathmandu Lake in the central part of the valley is estimated to be about 70 m.

An exploitation model and performance predictions for the ahuachapán geothermal field, El Salvador

The Ahuachapán geothermal field in El Salvador has been producing electrical power since 1975. The power plant currently generates at approximately 50 per cent of its total installed capacity of 95MW e because of a substantial reservoir pressure drawdown and limited drilling of make-up wells. The focus of this study is to develop means for increasing the power production over the next 30 years. One possible option is to devise an injection scheme to decrease the pressure decline and increase the energy recovery from the reservoir. Another possibility is to drill step-out wells to increase the size of the wellfield. A three-dimensional numerical model of the field has been developed to determine the effects of injection and expanded fluid production. The model was used to predict the responses of the existing and proposed production wells for different levels of electrical power generation. The overall reservoir response to different exploitation and injection scenarios was also investigated. The model predicts that the geothermal system can provide steam to generate 90 MW e, for no more than 20 y, even with reinjection and a large-scale drilling program. The results also indicate that the system can produce about 75 MW e for a 30-y period with significant reinjection and the drilling of about 20 new production wells.

Waste Management For A Large-Scale Drilling Project

Abstract In 1985 Shell Canada Limited completed the drilling of 209 wells as part of its Peace River Expansion Project (PREP). This projeel generated a combined total of 34 000 m3 of solid and liquid drilling wastes. Due to the volume of the wastes to be generated and because potassium chloride (KCl) salts would be present in the wastes, a waste management plan was required. The objectives of this plan were:Minimize the volume of wastes generated.Treat and re-use as much waste liquid in the drilling operation as possible.Dispose of all remaining wastes at project completion in an economical and environmentally acceptable manner. Prior to and during the project, various government agencies raised additional environmental concerns over those initially identified. To address these concerns, hydrogeological and environmental studies were undertaken. This paper discusses the approach used to develop and implement a waste management plan for a large-scale drilling project. Recommendations are provided to refine this plan for future projects. Introduction Over the past five years waste management has become a much more important aspect of the drilling operation. This has come about due to increased drilling sump disposal costs and increased environmental awareness. For Shell Canada Limited, the importance of having an effective waste management project in place for its Peace River Expansion Project (PREP) was very important due to the large volume of wastes expected to be generated as well as the environmental sensitivity of the area. Three rigs were used to directionally drill 209 wells from eight pads (Figs. 1 and 2). Each rig had centralized mud and power systems. Drilling time averaged 3.2 days per well. The pads were built on muskeg. All drilling wastes therefore had to be temporarily stored in surface tanks prior to transport to an off-lease site. Waste management has typically been considered by many as only that portion of our business which deals with the wastes remaining after the completion of drilling. On this project, the concept of waste management was expanded to also include that portion of our business which deals with wastes while they are being generated. The waste management program looked at not only the wastes that were produced but also the process by which they were produced. The over-all waste management program, therefore, focused on the areas of solids control, sump management, waste water re-use, waste water disposal and solids disposal. Waste Management Plan The waste management plan had the following main objectives:Minimize the volume of wastes generated.Treat and re-use as much waste liquid in the drilling operation as possible.Dispose of all remaining wastes at project completion in an economical and environmentally acceptable manner. To help meet the objective of minimizing the volume of wastes generated, a monitoring program was implemented. This involved monitoring the volume of wastes transported from each rig on a daily basis. This data was entered into a computer data system to be used for regular performance updates. This information was used to assist operations personnel in monitoring their waste management performance.

The Pass at Thermopylae, Greece

Conflicts among historians over the battle at Thermopylae in 480 B.C. tend to center around supposed inconsistencies between ancient sources, particularly Herodotus, and the modern topography of the region. The area, however, is one of extensive tectonic activity, fluctuations in sea level, and sediment deposition. Any attempt to reconstruct ancient events on the basis of modern topography alone is therefore bound to be misleading. Precise paleogeographic reconstruction would require a large-scale drilling program. This study involved the drilling and analysis of seven core holes in sediments infilling the Gulf of Malia. Results clearly demonstrate a Holocene epoch marine incursion to the far west of the Malian embayment and subsequent considerable variation over time in the physiography at Thermopylae. We have reconstructed the shoreline for ca. 480 B.C. and examined variations in the morphology of the middle gate with respect to the width of the pass. Geological and geomorphic evidence suggest that the pass at Thermopylae was closed for long portions of recorded history and may therefore have had less relative importance as a route into southern Greece.