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John R. SanFilipo

Publications and source records attributed to John R. SanFilipo.

At least 19 recordsLinked to original sources
USGS2020

Coal biomethanation potential of various ranks from Pakistan: A possible alternative energy source

The present study investigated the possibility of microbial transformations of coal to gas (biogasification) as an alternative to conventional coal mining because this approach has the potential to be less expensive, cleaner, and providinge greater access to deeper coal resources. Biogasification is often associated with low rank coal such as lignite and subbituminous coal that hasve produced enough coalbed methane to be commercially viable in the United States and Australia. However, little work has been done to analyze the potential of biogasification in higher rank coal. For this purpose, bioassay using a wetland-derived consortium, and a coal-derived consortium were used to analyze coal samples from Pakistan belonging to different ranks (lignite to semi-anthracite). Among all samples a low volatile bituminous coal produced the maximum methane 34.95 µmol CH4/g coal with the wetland-derived microbial consortium, followed by subbituminous coal (30.18 µmol CH4/g coal). Lower methane levels were recorded with the coal-derived consortium, with subbituminous coal yielding the highest concentration (25.1 µmol CH4/g coal). Methane levels appeared to be increasing on the last measurement indicating the coal-derived consortium was slower than the wetland-derived consortium but could still catalyze biogasification in higher rank coals. Quantitative polymerase chain reaction analysis for mcrA functional genes suggested indicated that the microbial community members that produce methane (methanogens) varied during the incubations. Energy conversion efficiency of different strategies (other biological and underground coal gasification processes) was also compared and discussed. This study was the first to compare bioassay using consortia of microbes non-indigenous and indigenous to coal and indicate the potential of biogasification from many different coalbeds across Pakistan.

Article↗
USGS2015

Structural degradation of Thar lignite using MW1 fungal isolate: optimization studies

Biological degradation of low-rank coals, particularly degradation mediated by fungi, can play an important role in helping us to utilize neglected lignite resources for both fuel and non-fuel applications. Fungal degradation of low-rank coals has already been investigated for the extraction of soil-conditioning agents and the substrates, which could be subjected to subsequent processing for the generation of alternative fuel options, like methane. However, to achieve an efficient degradation process, the fungal isolates must originate from an appropriate coal environment and the degradation process must be optimized. With this in mind, a representative sample from the Thar coalfield (the largest lignite resource of Pakistan) was treated with a fungal strain, MW1, which was previously isolated from a drilled core coal sample. The treatment caused the liberation of organic fractions from the structural matrix of coal. Fungal degradation was optimized, and it showed significant release of organics, with 0.1% glucose concentration and 1% coal loading ratio after an incubation time of 7 days. Analytical investigations revealed the release of complex organic moieties, pertaining to polyaromatic hydrocarbons, and it also helped in predicting structural units present within structure of coal. Such isolates, with enhanced degradation capabilities, can definitely help in exploiting the chemical-feedstock-status of coal.

Thar coalfield↗
USGS2013

Fungal degradation of coal as a pretreatment for methane production

Coal conversion technologies can help in taking advantage of huge low rank coal reserves by converting those into alternative fuels like methane. In this regard, fungal degradation of coal can serve as a pretreatment step in order to make coal a suitable substrate for biological beneficiation. A fungal isolate MW1, identified as Penicillium chrysogenum on the basis of fungal ITS sequences, was isolated from a core sample of coal, taken from a well drilled by the US. Geological Survey in Montana, USA. The low rank coal samples, from major coal fields of Pakistan, were treated with MW1 for 7 days in the presence of 0.1% ammonium sulfate as nitrogen source and 0.1% glucose as a supplemental carbon source. Liquid extracts were analyzed through Excitation–Emission Matrix Spectroscopy (EEMS) to obtain qualitative estimates of solubilized coal; these analyses indicated the release of complex organic functionalities. In addition, GC–MS analysis of these extracts confirmed the presence of single ring aromatics, polyaromatic hydrocarbons (PAHs), aromatic nitrogen compounds and aliphatics. Subsequently, the released organics were subjected to a bioassay for the generation of methane which conferred the potential application of fungal degradation as pretreatment. Additionally, fungal-mediated degradation was also prospected for extracting some other chemical entities like humic acids from brown coals with high huminite content especially from Thar, the largest lignite reserve of Pakistan.

Sindh Province↗
USGS2011

Paleocene coal deposits of the Wilcox Group, Northeast Texas

The surface exposure of the Paleocene Wilcox Group in northeast Texas varies in width from 9 to 27 mi along an arcuate outcrop that extends southwest approximately 156 mi from the Texas-Arkansas State line to 32° latitude. Parts of Bowie, Camp, Cass, Franklin, Henderson, Hopkins, Morris, Navarro, Rains, Titus, Van Zandt, and Wood Counties are included in this outcrop belt (Figure 1). This area forms the northwestern flank of the East Texas Basin (Figure 2), the axis of which separates northeast Texas from the Sabine uplift structural area. The Wilcox Group dips south and southeast at 2° or less toward the axis of the East Texas Basin, with the exception of local salt-dome structures and a transcurrent structural high that extends from Monticello to Martin Lake (Figure 1).

Lousiana, Oklahoma, Texas↗
USGS2011

Paleocene coal deposits of the Wilcox group, central Texas

Coal deposits in the Wilcox Group of central Texas have been regarded as the richest coal resources in the Gulf Coastal Plain. Although minable coal beds appear to be less numerous and generally higher in sulfur content (1 percent average, as-received basis; table 1) than Wilcox coal deposits in the Northeast Texas and Louisiana Sabine assessment areas (0.5 and 0.6 percent sulfur, respectively; table 1), net coal thickness in coal zones in central Texas is up to 32 ft thick and more persistent along strike (up to 15 mi) at or near the surface than coals of any other Gulf Coast assessment area. The rank of the coal beds in central Texas is generally lignite (table 1), but some coal ranks as great as subbituminous C have been reported (Mukhopadhyay, 1989). The outcrop of the Wilcox Group in central Texas strikes northeast, extends for approximately 140 mi between the Trinity and Colorado Rivers, and covers parts of Bastrop, Falls, Freestone, Lee, Leon, Limestone, Milam, Navarro, Robertson, and Williamson Counties (Figure 1). Three formations, in ascending order, the Hooper, Simsboro, and Calvert Bluff, are recognized in central Texas (Figure 2). The Wilcox Group is underlain conformably by the Midway Group, a mudstone-dominated marine sequence, and is overlain and scoured locally by the Carrizo Sand, a fluvial unit at the base of the Claiborne Group.

Texas↗
USGS2011

Wilcox group (Paleocene to Eocene) coals of the Sabine Uplift area, Texas and Louisiana

The Wilcox Group (Paleocene to Eocene) of the Sabine uplift, a structural arch in northeastern Texas and northwestern Louisiana (Figure 1), has lignite zones that approach subbituminous rank (see Chapter 4, this publication). These coals are among the highest quality resources known within the Gulf Coastal Plain because of their low ash yield and sulfur content. The surface expression of the Sabine uplift is defined by the contact between coal-bearing rocks of the Wilcox Group and overlying fluvial rocks of the Carrizo Sand, which is the basal unit of the Claiborne Group (Figures 2, 3). The Sabine uplift study area includes parts of Harrison, Marion, Nacogdoches, Panola, Rusk, Sabine, San Augustine, and Shelby Counties in Texas and Bossier, Caddo, De Soto, Natchitoches, Red River, and Sabine Parishes in Louisiana (Figure 1). Adjacent counties and parishes that include the subsurface Wilcox Group extend the regional Sabine uplift area. The Wilcox in the subsurface is underlain by the Midway Group (Figure 3), a mudstone-dominated marine sequence of Paleocene age. Quaternary alluvium and terrace deposits overlying the Wilcox Group at the surface are limited to areas of modern drainage. The total thickness of the Wilcox Group within the Sabine uplift area ranges from approximately 400 ft on outcrop to 2500 ft in subsurface (Kaiser, 1990). In a few places, the contact between the overlying Carrizo Sand and Wilcox Group is erosional, but in other places, the contact is gradational.

Louisiana, Texas↗
USGS2011

Upper Cretaceous bituminous coal deposits of the Olmos Formation, Maverick County, Texas

This report describes the bituminous coal deposits of the Olmos Formation (Navarro Group, Upper Cretaceous; Figures 1, 2) of Maverick County in south Texas. Although these were not evaluated quantitatively as part of the current Gulf Coastal Plain coal-resource assessment, a detailed review is presented in this chapter. Prior to the late 1920s, these coal beds were mined underground on a large scale in the vicinity of Eagle Pass, Texas (Figure 1). Since the 1970s, Olmos Formation coals have been mined extensively in both underground and surface mines in nearby Coahuila, Mexico, to supply mine-mouth fuel for power generation at a plant nearby. A tract northeast of Eagle Pass was permitted in the late 1990s for surface mining. In east-central Maverick County, a coalbed methane field is being developed in coal beds of the lower part of the Olmos Formation (Barker et al., 2002; Scott, 2003).

Texas↗
USGS2011

Paleogene coal deposits of the Wilcox group and the Indio formation of south Texas

Coal deposits of the undivided Wilcox Group and its southern equivalent Indio Formation (Paleogene) of south Texas are among the coal resources that are not evaluated quantitatively in the current Gulf Coastal Plain coal re-source assessment. South Texas Wilcox and Indio coals have not been extensively mined, nor have they been mined commercially for at least the past 60 years. These coals constitute only about 1 percent of the demonstrated coal resources within the Texas Gulf Coastal Province. In contrast to the Wilcox coal resources of the assessed areas of the Sabine uplift of Texas and Louisiana, and of northeast Texas and central Texas (see Warwick et al., 2011a, b, c), Wilcox and Indio coal beds of south Texas are few in number, each generally less than 5 ft thick, and highly discontinuous. Furthermore, analytical data indicate that the sulfur content and ash yields of south Texas Wilcox and Indio coals generally exceed those of other Texas coals. Although these and other factors preclude the likely development of Wilcox or Indio coal resources in the near future, the comparatively elevated rank of these deposits has attracted recent interests related to coalbed methane production (SanFilipo, 1999; Warwick et al., 2002a, 2007b).

Texas↗
USGS2011

Introduction

The National Coal Resource Assessment (NCRA) team of the U.S. Geological Survey (USGS) has assessed the quantity and quality of coal beds and zones that could be mined during the next 20 years or more. Geologic, geochemical, and resource information was collected and compiled for the five major coal-producing regions of the United States: the Appalachian Basin, Illinois Basin, Northern Rocky Mountains and Great Plains, Colorado Plateau, and the Gulf of Mexico Coastal Plain, (Gulf Coast) (Figure 1). In particular, the NCRA assessed coal-quality information and characterized environmentally significant trace elements, such as arsenic and mercury, that are defined in and administered by 1990 Clean Air Act Amendments (U.S. Environmental Protection Agency, 1990). The results of various USGS coal assessment efforts may be found at: http://energy.cr.usgs.gov/coal/coal_assessments/index.html, and a summary of the results from all assessment areas can be found in Ruppert et al. (2002) and Dennen (2009).

Louisiana, Texas↗
USGS2010

Chemical analyses in the World Coal Quality Inventory

The main objective of the World Coal Quality Inventory (WoCQI) was to collect and analyze a global set of samples of mined coal during a time period from about 1995 to 2006 (Finkelman and Lovern, 2001). Coal samples were collected by foreign collaborators and submitted to country specialists in the U.S. Geological Survey (USGS) Energy Program. However, samples from certain countries, such as Afghanistan, India, and Kyrgyzstan, were collected collaboratively in the field with USGS personnel. Samples were subsequently analyzed at two laboratories: the USGS Inorganic Geochemistry Laboratory located in Denver, CO and a commercial laboratory (Geochemical Testing, Inc.) located in Somerset, PA. Thus the dataset, which is in Excel (2003) format and includes 1,580 samples from 57 countries, does not have the inter-laboratory variability that is present in many compilations. Major-, minor-, and trace-element analyses from the USGS laboratory, calculated to a consistent analytical basis (dry, whole-coal) and presented with available sample identification information, are sorted alphabetically by country name. About 70 percent of the samples also have data from the commercial laboratory, which are presented on an as-received analytical basis. The USGS initiated a laboratory review of quality assurance in 2008, covering quality control and methodology used in inorganic chemical analyses of coal, coal power plant ash, water, and sediment samples. This quality control review found that data generated by the USGS Inorganic Geochemistry Laboratory from 1996 through 2006 were characterized by quality practices that did not meet USGS requirements commonly in use at the time. The most serious shortcomings were (1) the adjustment of raw sample data to standards when the instrument values for those standards exceeded acceptable limits or (2) the insufficient use of multiple standards to provide adequate quality assurance. In general, adjustment of raw data to account for instrument 'drift' is an acceptable practice within strictly defined limits. During the denoted period, USGS required that the maximum adjustment of instrument values, guided by calibration standards, was not allowed to exceed 10 percent. However, in some cases, the Inorganic Geochemistry Laboratory released data that were adjusted by more than 10 percent and (or) were not constrained by an adequate number of control standards. Original instrument values no longer exist for about 80 percent of the analyses during this period; therefore, the acceptability of drift corrections for most of the samples analyzed cannot be determined. For these reasons, the WoCQI data from the USGS Inorganic Geochemistry Laboratory should be used with care. For more information, individuals may contact laboratory management at EnergyLabs@usgs.gov with specific questions about particular datasets or analytical attributes. Standard USGS sampling methods were provided and recommended to collaborators, but the analyzed samples may or may not be representative of their locale; for some samples, only limited information is available concerning sample provenance. Single samples cannot represent spatial or temporal variability within a coal area. Geochemical datasets of U.S. coals can be found in the COALQUAL database (Bragg and others, 1997) and the National Coal Quality Inventory (Hatch and others, 2006), as only non-U.S. sample data are presented in the WoCQI. Although the WoCQI does not contain worldwide coverage of coal deposits, it is truly a unique and valuable compilation. The information in the WoCQI should prove useful for identifying possible areas for future global coal research.

Open-File Report↗
USGS2007

The Lakhra Anticline - An Active Structure of Pleistocene to Holocene Age in Southern Pakistan

The Lakhra anticline is a breached north-trending structure northwest of Hyderabad in Sindh Province, Pakistan. About 340 meters (m) of Paleocene to Holocene strata have been eroded from the core of the anticline. North-trending normal faults transect the anticline at a low angle, are vertical, and form a set of nested grabens. Lakhra Nala and Siph Nala were formed where antecedent streams eroded the nalas (canyons, gullies, ravines, or watercourses and the streams in them) as the anticline rose. Lakhra Nala flows onto the Indus River flood plain, which is accumulating about 6.1 m of alluvium per 1,000 years. If the anticline rose at an equivalent rate, it started to rise about 60,000 years ago.

Scientific Investigations Report↗
USGS2002

Preliminary evaluation of the coalbed methane potential of the Gulf Coastal Plain, USA and Mexico

Several areas in the Gulf Coast have potential for coalbed gas accumulations. These areas include parts of southern Alabama and Mississippi, north-central Louisiana, northeast, east-central and south Texas and northeastern Mexico. The coal deposits in these areas vary in rank, thickness, lateral extent and gas content, and range in age from Late Cretaceous to Eocene. Gas desorption tests conducted by the U.S. Geological Survey (USGS) on shallow (2,000 ft [609 m]) Paleocene (Wilcox-Midway Groups) coals of southeastern Mississippi indicate that the coalbeds contain some methane. Measured gas contents range from 0 to 19 scf/ton (0.19 to 0.59 cc/g; dry, ash-free) and average about 15 scf/ton (0.5 cc/g). These coals have apparent ranks of lignite to subbituminous (vitrinite reflectance of 0.3 to 0.4% R omax ) at shallow depths and subbituminous to bituminous (0.5 to 0.6% R omax ) in the deeper parts of the basin. Adsorption isotherm data indicate that Wilcox Group coals are undersaturated and have methane gas-storage capacities similar to those of the subbituminous coals in the Powder River basin, Wyoming. In the primary areas where Wilcox Group coalbeds are mined and subsurface data are available, net coal thickness ranges from about 10 to 50 ft (3 to 15 m), which is much less than coal thickness in the Powder River basin, which can be 300 ft (91 m). Upper Cretaceous and Paleocene-Eocene coals of south Texas and northeastern Mexico are subbituminous to bituminous rank (up to 0.6% R omax ). Some methane has been produced commercially from thin coal beds (13 ft [4 m] net) and associated sandstone at shallow depths (

Gulf Coast↗
USGS2000

A primer on the occurrence of coalbed methane in low-rank coals, with special reference to its potential occurrence in Pakistan

Introduction: This report compiles and updates a series of correspondence that took place between 1998 and early 2000 among the author and representatives of various consulting groups operating in the coal sector of Pakistan. The purpose of the original correspondence was to introduce basic concepts of coalbed methane (CBM) in low-rank coals to planners and other parties interested in the development of Pakistan's coal, particularly the large deposits of the Thar desert area of Sindh Province that were recently discovered (SanFilipo and Khan, 1994) by the Geological Survey of Pakistan (GSP) and the U.S. Geological Survey (USGS). The author tested two shallow boreholes in Sindh Province for CBM in 1992, including one in Thar, with very marginal results. Additional targets with better CBM prospects were recommended shortly thereafter (SanFilipo and others, 1994), but these were not followed up during subsequent drilling, nor were any other sites tested. Recent events, notably the rapid pace of CBM development in low-rank coals of the Powder River Basin of the U.S., and a show of CBM in commercial quantities in the Cambay Basin of India - both of which are similar in age and rank to most of Pakistan's coal - have indicated a need for reevaluating the initial CBM investigations made in Pakistan in 1992 and for a reassessment of the CBM prospects for the country at large.

Open-File Report↗
USGS2000

Preliminary Gulf Coast Coalbed Methane Exploration Maps: Depth to Wilcox, Apparent Wilcox Thickness and Vitrinite Reflectance

Strong economic controls on the viability of coalbed methane (CBM) prospects make coal geometry and coal property maps key elements in identifying sweet spots and production fairways. Therefore, this study seeks to identify the apparent prospective areas for CBM exploration in the Wilcox Group (Paleocene-Eocene) lignite and coalbeds by mapping net coal thickness, depth to coal, and coal rank (vitrinite reflectance). Economic factors are not considered in this CBM prospects study. Given the comparatively extensive gas pipeline and other production infrastructure development in the Gulf Coast Region, these factors seem less a control compared to other areas. However, open leasable public lands are minimal or nonexistent in the Gulf Coast region and access to the CBM prospects could be a problem.

Open-File Report↗