Didactic prediction of pore pressure: Case study in the Amazon Basin

The growth of the randomized controlled trial (RCT) as the “gold standard” for evaluation has justly been praised as an advance in the professionalization of social programs and projects, an “adoption of science” - in the words of the Lancet. None the less, the emphasis on the RCT biases funding for projects that distribute private goods and which focus on “low hanging fruit” in health, nutrition, and sanitation, simply because those areas lend themselves to the sort of measurement that works with RCTs. As a result, many project developers in the government and NGO sectors lament that a hegemonic focus on RCTs impedes creativity or new models that challenge traditional paradigms. This case study of CanalCanoa, a community video coaching project for indigenous parents of young children in the Rio Negro region of the Amazon Basin, offers techniques to measure for innovation. Instead of developing a new RCT for an extremely diverse population (27 ethnic groups) where traditional childcare methods are in historical flux because of urbanization, CanalCanoa measured variables shown by previous RCTs to be causally connected with positive development results. By researching the impact of the intervention on nutrition, language (multilingualism, use of traditional songs and stories), and social network expansion, CanalCanoa measured upstream indicators, thus mixing scientific rigor with an opportunity for innovation and providing important insight and reform of a theory of change.

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New Pore Pressure Evaluation Techniques for LAGIA-8 Well, Sinai, Egypt as a Case Study

International Journal of Geosciences ◽

10.4236/ijg.2016.71004 ◽

2016 ◽

Vol 07 (01) ◽

pp. 32-46 ◽

Cited By ~ 1

Author(s):

Ahmed Zakaria Noah

Keyword(s):

Pore Pressure ◽

Evaluation Techniques

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Transport of Saharan dust from the Bodélé Depression to the Amazon Basin: a case study

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-10-4345-2010 ◽

2010 ◽

Vol 10 (2) ◽

pp. 4345-4372 ◽

Cited By ~ 10

Author(s):

Y. Ben-Ami ◽

I. Koren ◽

Y. Rudich ◽

P. Artaxo ◽

S. T. Martin ◽

...

Keyword(s):

Atlantic Ocean ◽

Amazon Basin ◽

Marine Boundary Layer ◽

Average Concentration ◽

Saharan Dust ◽

Aerosol Layer ◽

Amazon Forest ◽

Close Link ◽

Bodele Depression

Abstract. Through long-range transport of dust, the Sahara desert supplies essential minerals to the Amazon rain forest. Since Saharan dust reaches South America mostly during the Northern Hemisphere winter, the dust sources active during winter are the main contributors to the forest. Given that the Bodélé depression area in Southwestern Chad is the main winter dust source, a close link is expected between the Bodélé emission patterns and volumes and the mineral supply flux to the Amazon. Until now, the particular link between the Bodélé and the Amazon forest was based on sparse satellite measurements and modeling studies. In this study, we combine a detailed analysis of space-borne and ground data with reanalysis model data and surface measurements taken in the Central Amazon during the Amazonian Aerosol Characterization Experiment (AMAZE-08) in order to explore the validity and the nature of the proposed link between the Bodélé depression and the Amazon forest. This case study follows the dust events of 11–16 and 18–27 February 2008, from the emission in the Bodélé over West Africa, the crossing of the Atlantic Ocean, to the observed effects above the Amazon canopy about 10 days after the emission. The dust was lifted by surface winds stronger than 14 m s−1, usually starting early in the morning. The lofted dust mixed with biomass burning aerosols over Nigeria, was transported over the Atlantic Ocean, and arrived over the South American continent. The top of the aerosol layer reached above 3 km, and the bottom merged with the marine boundary layer. The arrival of the dusty air parcel over the Amazon forest increased the average concentration of aerosol crustal elements by an order of magnitude.

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Triple MPD Technique for Drilling and Intelligent Completion Deployment on an Abandoned Deepwater Well

10.4043/31223-ms ◽

2021 ◽

Author(s):

André Alonso Fernandes ◽

Eduardo Schnitzler ◽

Fabio Fabri ◽

Leandro Grabarski ◽

Marcos Vinicius Barreto Malfitani ◽

...

Keyword(s):

Pore Pressure ◽

Fluid Loss ◽

Final Project ◽

Well Design ◽

Open Hole ◽

Loss Control ◽

Fluid Losses ◽

Complex Cases ◽

Total Fluid

Abstract This is a case study of a presalt well that required the use of 3 different MPD techniques to achieve its goals. The well was temporary abandoned when conventional techniques failed to reach the final depth. Total fluid losses in the reservoir section required changing the well design and its completion architecture. The new open hole intelligent completion design had to be used to deliver the selective completion in this challenging scenario. From the hundreds of wells drilled in the Santos basin presalt, there are some wells with tight or no operational drilling window. In order to drill these wells different MPD techniques are used. In most cases, the use of Surface Backpressure (SBP) technique is suitable for drilling the wells to its final depth. For the more complex cases, when higher fluid loss rates occur, the use of SBP and Pressurized Mud Cap Drilling (PMCD) enables the achievement of the drilling and completion objectives. After the temporary abandonment of this specific well in 2018, the uncertainty of the pore pressure could not ensure that the SBP and PMCD techniques would be applicable when reentering the well. To avoid difficult loss control operations, the completion team changed the intelligent completion design to include a separated lower completion, enabling its installation with the MPD system. Besides the previously used MPD techniques, the integrated final project considered an additional technique, Floating Mud Cap Drilling (FMCD), as one of the possible contingencies for the drilling and completion phases. Well reentry and drilling of the remaining reservoir section included the use all the previously mentioned MPD techniques (SBP, PMCD and FMCD). The lower completion deployment utilized the FMCD technique to isolate the formation quickly and efficiently, without damaging the reservoir. The planning and execution of the well faced additional difficulties due to the worldwide pandemic and personnel restrictions. The success from the operation was complete with no safety related events and within the planned budget. At the end, the execution team delivered a highly productive well with an intelligent completion system fully functional, through an integrated and comprehensive approach. MPD use on deepwater wells is relatively new. Different operators used several approaches and MPD techniques to ensure safety and success during wells constructions over the last decade. This paper demonstrates the evolution of MPD techniques usage on deepwater wells.

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A Case Study of Real Time Follow-up of Pore Pressure and Fracturing Pressure, in Wildcat Exploration Well, Leading to Architecture Lightening

First EAGE Workshop on Pore Pressure Prediction ◽

10.3997/2214-4609.201700062 ◽

2017 ◽

Author(s):

S. Gazet-Talvande

Keyword(s):

Real Time ◽

Pore Pressure ◽

Exploration Well

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The influence of long- and short-term volcanic strain on aquifer pressure: a case study from Soufrière Hills Volcano, Montserrat (W.I.)

Geophysical Journal International ◽

10.1093/gji/ggaa354 ◽

2020 ◽

Vol 223 (2) ◽

pp. 1288-1303

Author(s):

K Strehlow ◽

J Gottsmann ◽

A Rust ◽

S Hautmann ◽

B Hemmings

Keyword(s):

Water Level ◽

Pore Pressure ◽

Crustal Deformation ◽

Water Levels ◽

Short Term ◽

Soufriere Hills Volcano ◽

Soufrière Hills Volcano ◽

Water Level Changes ◽

Soufriere Hills

Summary Aquifers are poroelastic bodies that respond to strain by changes in pore pressure. Crustal deformation due to volcanic processes induces pore pressure variations that are mirrored in well water levels. Here, we investigate water level changes in the Belham valley on Montserrat over the course of 2 yr (2004–2006). Using finite element analysis, we simulate crustal deformation due to different volcanic strain sources and the dynamic poroelastic aquifer response. While some additional hydrological drivers cannot be excluded, we suggest that a poroelastic strain response of the aquifer system in the Belham valley is a possible explanation for the observed water level changes. According to our simulations, the shallow Belham aquifer responds to a steadily increasing sediment load due to repeated lahar sedimentation in the valley with rising aquifer pressures. A wholesale dome collapse in May 2006 on the other hand induced dilatational strain and thereby a short-term water level drop in a deeper-seated aquifer, which caused groundwater leakage from the Belham aquifer and thereby induced a delayed water level fall in the wells. The system thus responded to both gradual and rapid transient strain associated with the eruption of Soufrière Hills Volcano (Montserrat). This case study gives field evidence for theoretical predictions on volcanic drivers behind hydrological transients, demonstrating the potential of hydrological data for volcano monitoring. Interrogation of such data can provide valuable constraints on stress evolution in volcanic systems and therefore complement other monitoring systems. The presented models and inferred results are conceptually applicable to volcanic areas worldwide.

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