Seismic stratigraphy of the Ontong Java Plateau

The Ontong Java Plateau, a large, deep-water carbonate plateau in the western equatorial Pacific, is an ideal location for studying responses of carbonate sedimentation to the effects of changing paleoceanographic conditions. These carbonate responses are often reflected in the physical properties of the sediment, which in turn control the appearance of seismic reflection profiles. Seismic stratigraphy analyses, correlating eight reflector horizons to each drill site, have been conducted in an attempt to map stratigraphic data. Accurate correlation of seismic stratigraphic data to drilling results requires conversion of traveltime to depth in meters. Synthetic seismogram models, using shipboard physical properties data, have been generated in an attempt to provide this correlation. Physical properties, including laboratory-measured and well-log data, were collected from sites drilled during Deep Sea Drilling Project Legs 30 and 89, and Ocean Drilling Program Leg 130, on the top and flank of the Ontong Java Plateau. Laboratory-measured density is corrected to in-situ conditions by accounting for porosity rebound resulting from removal of the sediment from its overburden. The correction of laboratory-measured compressional velocity to in situ appears to be largely a function of increases in elastic moduli (especially shear rigidity) with depth of burial, more than a function of changes in temperature, pressure, or density (porosity rebound). Well-log velocity and density data for the ooze intervals were found to be greatly affected by drilling disturbance; hence, they were disregarded and replaced by lab data for these intervals. Velocity and density data were used to produce synthetic seismograms. Correlation of seismic reflection data with synthetic data, and hence with depth below seafloor, at each drill site shows that a single velocity-depth function exists for sediments on the top and flank of the Ontong Java Plateau. A polynomial fit of this function provides an equation for domain conversion: Depth (mbsf) = 44.49 + 0.800(traveltime[ms]) + 3.308 × 10 4 (traveltime[ms]2 ) Traveltime (ms) = -35.18 + 1.118(depth[mbsf]) - 1.969 × KT* (depth[mbsf]2 ) Seismic reflection profiles down the flank of the plateau undergo three significant changes: (1) a drastic thinning of the sediment column with depth, (2) changes in the echo-character of the profile (development of seismic facies), and (3) loss of continuous, coherent reflections. Sediments on the plateau top were largely deposited by pelagic processes, with little significant postdepositional or syndepositional modification. Sediments on the flank of the plateau are also pelagic, but they have been modified by faulting, erosion, and mass movement. These processes result in disrupted and incoherent reflectors, development of seismic facies, and redistribution of sediment on the flank of the plateau. Seismic stratigraphic analyses have shown that the sediment section decreases in thickness by as much as 65% between water depths of 2000 m water depth (at the top of the plateau) and 4000 m (near the base of the plateau). Thinning is attributed to increasing carbonate dissolution with depth. If this assumption is correct, then changes in the relative thicknesses of seismostratigraphic units at each drill site are indicative of changes in the position of the lysocline and the dissolution gradient between the lysocline and the carbonate compensation depth. We think that a shallow lysocline in the early Miocene caused sediment thinning. A deepening of the lysocline in the late-early Miocene caused relative thickening at each site. Within the middle Miocene, a sharp rise in lysoclinal depth occurs, concurrent with a steepening of the dissolution gradient. These events result in sediment thinning at all four sites. The thicker sections in the late Miocene likely correspond to a deepening of the lysocline, and a subsequent rise in the lysocline again hinders accumulation of sediment in the very late Miocene and Pliocene

New approaches to the measurement of chlorophyll, related pigments and productivity in the sea

In the 1984 SBIR Call for Proposals, NASA solicited new methods to measure primary production and chlorophyll in the ocean. Biospherical Instruments Inc. responded to this call with a proposal first to study a variety of approaches to this problem. A second phase of research was then funded to pursue instrumentation to measure the sunlight stimulated naturally occurring fluorescence of chlorophyll in marine phytoplankton. The monitoring of global productivity, global fisheries resources, application of above surface-to-underwater optical communications systems, submarine detection applications, correlation, and calibration of remote sensing systems are but some of the reasons for developing inexpensive sensors to measure chlorophyll and productivity. Normally, productivity measurements are manpower and cost intensive and, with the exception of a very few expensive multiship research experiments, provide no contemporaneous data. We feel that the patented, simple sensors that we have designed will provide a cost effective method for large scale, synoptic, optical measurements in the ocean. This document is the final project report for a NASA sponsored SBIR Phase 2 effort to develop new methods for the measurements of primary production in the ocean. This project has been successfully completed, a U.S. patent was issued covering the methodology and sensors, and the first production run of instrumentation developed under this contract has sold out and been delivered

Machine Learning Based Real-Time Quantification of Production from Individual Clusters in Shale Wells

Over the last two decades, there has been advances in downhole monitoring in oil and gas wells with the use of Fiber-Optic sensing technology such as the Distributed Temperature Sensing (DTS). Unlike a conventional production log that provides only snapshots of the well performance, DTS provides continuous temperature measurements along the entire wellbore. Whether by fluid extraction or injection, oil and gas production changes reservoir conditions, and continuous monitoring of downhole conditions is highly desirable. This research study presents a tool for real-time quantification of production from individual perforation clusters in a multi-stage shale well using Artificial Intelligence and Machine Learning. The technique presented provides continuous production log on demand thereby providing opportunities for the optimization of completions design and hydraulic fracture treatments of future planned wells. A Fiber-Optic sensing enabled horizontal well MIP-3H in the Marcellus Shale has been selected for this work. MIP-3H is a 28-stage horizontal well drilled in July 2015, as part of a Department of Energy (DOE)-sponsored project - Marcellus Shale Energy & Environment Laboratory (MSEEL). A one-day conventional production logging operation has been performed on MIP-3H using a flow scanner while the installed Fiber-Optic DTS unit has collected temperature measurements every three hours along the well since completion. An ensemble of machine learning models has been developed using as input the DTS measurements taken during the production logging operation, details of mechanical logs, completions design and hydraulic fracture treatments data of the well to develop the real-time shale gas production monitoring tool

Development and Application of a Performance and Operational Feasibility Guide to Facilitate Adoption of Soil Moisture Sensors

Soil moisture sensors can be effective and promising decision-making tools for diverse applications and audiences, including agricultural managers, irrigation practitioners, and researchers. Nevertheless, there exists immense adoption potential in the United States, with only 1.2 in 10 farms nationally using soil moisture sensors to decide when to irrigate. This number is much lower in the global scale. Increased adoption is likely hindered by lack of scientific support in need assessment, selection, suitability and use of these sensors. Here, through extensive field research, we address the operational feasibility of soil moisture sensors, an aspect which has been overlooked in the past, and integrate it with their performance accuracy, in order to develop a quantitative framework to guide users in the selection of best-suited sensors for varying applications. These evaluations were conducted for nine commercially available sensors under silt loam and loamy sand soils in irrigated cropland and rainfed grassland for two different installation orientations [sensing component parallel (horizontal) and perpendicular (vertical) to the ground surface] typically used. All the sensors were assessed for their aptness in terms of cost, ease of operation, convenience of telemetry, and performance accuracy. Best sensors under each soil condition, sensor orientation, and user applications (research versus agricultural production) were identified. The step-by-step guide presented here will serve as an unprecedented and holistic adoption-assisting resource and can be extended to other sensors as well

Interpretation of Downhole Temperature Measurements for Multistage Fracture Stimulation in Horizontal Wells

The ideal outcomes of multistage hydraulic fracturing in horizontal wells are to create a controlled fracture distribution along the horizontal well with maximum contact with the reservoir which can provide the sufficient production after stimulation. Downhole temperature sensing is one of the valuable tools to monitor hydraulic fracture treatment process and diagnose fracture performance during production. Today, there are still many challenges in quantitative interpretations of distributed downhole temperature measurements for flow profiling. These challenges come from the following aspects: the uncertainties of the parameters ranging from the reservoir properties, well completion, to fracture geometry; the need of a fast and robust forward model to simulate temperature behavior from injection, shut-in and production accurately; the need of an inversion methodology that can converge fast, reduce the uncertainties and lead to a practically meaningful solution. In this study, an integrated multiphase black-oil thermal and flow model is presented. This model is developed to simulate the transient temperature and flow behavior during injection, shut-in, and production for multistage hydraulic fractured horizontal wells. The model consists of a reservoir model and a wellbore model, which are coupled interactively through boundary conditions to each other. It is assumed that the oil and water components are immiscible, and the gas component is only soluble in oil. Comparing with the compositional model, this model has an improved computational efficiency while still maintains the maximum robustness. This study gives guidance on when and how to apply this black-oil thermal model to fulfill its full advantages. This study also proposed a new temperature interpretation methodology which incorporates the black-oil thermal model as the forward model for temperature simulation and the inversion model for inverting the flow rate profile along the wellbore by matching the simulated temperature with the measured temperature. The sensitivity study is first performed to determine the impact of parameters on temperature behavior such as fracture half-length, fracture permeability, matrix permeability, and matrix porosity. The inversion model uses the initial analysis on temperature gradient to identify the initial guess of fluid distribution which leads to a faster convergence as well as a sensible solution. The Levenberg-Marquart algorithm is adopted to update the inversion parameters during each iteration. A synthetic example with multiple fractures is presented to test the interpretation procedure’s accuracy and speed. The interpretation methodology is further applied to two different filed cases. One is a single-phase gas producing horizontal well with multiple hydraulic fractures; the other one is a two-phase water-oil producing horizontal well with multiple hydraulic fractures. This study illustrates how to adjust the methodologies and perform the analysis for each particular case and explains how to reduce the uncertainties and increase the interpretation efficiency. The results reveal that this temperature interpretation methodology is efficient and effective to translate temperature measurements to flow profile quantitatively with reasonable assumptions

Field application of an interpretation method of downhole temperature and pressure data for detecting water entry in horizontal/highly inclined gas wells

In the oil and gas industry today, continuous wellbore data can be obtained with high precision. This accurate and reliable downhole data acquisition is made possible by advancements in permanent monitoring systems such as downhole pressure and temperature gauges and fiber optic sensors. The monitoring instruments are increasingly incorporated as part of the intelligent completion in oil wells where they provide bottomhole temperature, pressure and sometimes volumetric flow rate along the wellbore - offering the promise of revolutionary changes in the way these wells are operated. However, to fully realize the value of these intelligent completions, there is a need for a systematic data analysis process to interpret accurately and efficiently the raw data being acquired. This process will improve our understanding of the reservoir and production conditions and enable us make decisions for well control and well performance optimization. In this study, we evaluated the practical application of an interpretation model, developed in a previous research work, to field data. To achieve the objectives, we developed a simple and detailed analysis procedure and built Excel user interface for data entry, data update and data output, including diagnostic charts and graphs. By applying our interpretation procedure to the acquired field data we predicted temperature and pressure along the wellbore. Based on the predicted data, we used an inversion method to infer the flow profile - demonstrating how the monitored raw downhole temperature and pressure can be converted into useful knowledge of the phase flow profiles and fluid entry along the wellbore. Finally, we illustrated the sensitivity of reservoir parameters on accuracy of interpretation, and generated practical guidelines on how to initialize the inverse process. Field production logging data were used for validation and application purposes. From the analysis, we obtained the production profile along the wellbore; the fluid entry location i.e. the productive and non-productive locations along the wellbore; and identified the fluid type i.e. gas or water being produced along the wellbore. These results show that temperature and pressure profiles could provide sufficient information for fluid identity and inflow distribution in gas wells

Integrated Ocean Drilling Program Expedition 317/319 Scientific Prospectus: Pacific Equatorial Age Transect

As the world's largest ocean, the Pacific is intricately linked to major changes in the global climate system. Throughout the Cenozoic, Pacific plate motion has had a northward component. Thus, the Pacific is unique in that the thick sediment bulge of biogenic-rich deposits from the currently narrowly focused zone of equatorial upwelling is slowly moving away from the Equator. Hence, older sections are not deeply buried and can be recovered by drilling. Previous drilling in this area during Ocean Drilling Program (ODP) Legs 138 and 199 was remarkably successful in giving us new insights into the workings of the climate and carbon system, productivity changes across the zone of divergence, time-dependent calcium carbonate dissolution, bio- and magnetostratigraphy, the location of the Intertropical Convergence Zone (ITCZ), and evolutionary patterns for times of climatic change and upheaval. Together with older Deep Sea Drilling Project drilling in the eastern equatorial Pacific, both legs also helped to delineate the position of the paleoequator and variations in sediment thickness from ~150°W to 110°W.The Pacific equatorial age transect (PEAT) science program is based on Integrated Ocean Drilling Program (IODP) Proposal 626 and consists of Expeditions 317 and 319, grouped into one science program. The goal is to recover a continuous Cenozoic record of the equatorial Pacific by drilling at the paleoposition of the Equator at successive crustal ages on the Pacific plate. Records collected from Expeditions 317 and 319 are to be joined with records of previous drilling during ODP Legs 138 and 199 to make a complete equatorial Pacific record from 0 to 55 Ma. Previously, ODP Legs 138 and 199 were designed as transects across the paleoequator in order to study the changing patterns of sediment deposition across equatorial regions at critical time intervals. As we have gained more information about the past movement of plates and when in Earth's history "critical" climate events took place, it becomes possible to drill an age transect ("flow-line") along the position of the Pacific paleoequator. The goal of this transect is to target important time slices where calcareous sediments have been best preserved and the sedimentary archive will allow us to reconstruct past climatic and tectonic conditions. Leg 199 enhanced our understanding of extreme changes of the calcium carbonate compensation depth (CCD) across major geological boundaries during the last 55 m.y. A very shallow CCD during most of the Paleogene makes it difficult to obtain well-preserved sediments during these stratigraphic intervals, but the strategy of site locations for the current two expeditions is designed to occupy the most promising sites and to obtain a unique sedimentary biogenic sediment archive for time periods just after the Paleocene/Eocene boundary event, Eocene cooling, the Eocene–Oligocene transition, the "one cold pole" Oligocene, the Oligocene–Miocene transition, and the Miocene. These new cores and data will significantly contribute to the objectives of the IODP Extreme Climates Initiative and will provide material that the previous legs were not able to recover.For logistical reasons, the PEAT science program is composed of two expeditions but is being implemented as a single science program to best achieve the overall objectives of Proposal 626. Participants on both expeditions (as well as approved shore-based scientists) will comprise a single science party with equal access to data and materials from both cruises. Sampling aboard the ship will be minimal, and the bulk of the sampling will be completed postcruise.The operational plan is to occupy eight sites along the age transect with the goal of recovering as complete a sedimentary succession as possible. This will probably require three holes to be cored at each site with wireline logging operations in one hole. Basement will be tagged in at least one of the holes. Expedition 317 will be directed primarily to sample the Neogene sites (proposed Sites PEAT-2C, 6C, and 7C, in priority order). The second expedition (319) will primarily sample the Paleogene sites (proposed Sites PEAT-1C, 3C, 4C, and possibly 5C, in priority order)

Expert-based development of a standard in CO2 sequestration monitoring technology

Bureau of Economic Geolog

Applications of aerospace technology to petroleum extraction and reservoir engineering

Through contacts with the petroleum industry, the petroleum service industry, universities and government agencies, important petroleum extraction problems were identified. For each problem, areas of aerospace technology that might aid in its solution were also identified, where possible. Some of the problems were selected for further consideration. Work on these problems led to the formulation of specific concepts as candidate for development. Each concept is addressed to the solution of specific extraction problems and makes use of specific areas of aerospace technology