Skip to main content
U.S. flag

An official website of the United States government

Publications

Filter Total Items: 2692

Geologic implications of gas hydrates in the offshore of India: Krishna-Godavari Basin, Mahanadi Basin, Andaman Sea, Kerala-Konkan Basin

Gas hydrate resource assessments that indicate enormous global volumes of gas present within hydrate accumulations have been one of the primary driving forces behind the growing interest in gas hydrates. Gas hydrate volumetric estimates in recent years have focused on documenting the geologic parameters in the “gas hydrate petroleum system” that control the occurrence of gas hydrates in nature. Th
Authors
Pushpendra Kumar, Timothy S. Collett, Ray Boswell, James R. Cochran, Malcolm Lall, Aninda Mazumdar, Mangipudi Venkata Ramana, Tammisetti Ramprasad, Michael Riedel, Kalachand Sain, Arun Vasant Sathe, Krishna Vishwanath, U.S. Yadav

Geologic implications of gas hydrates in the offshore of India: results of the National Gas Hydrate Program Expedition 01

The Indian National Gas Hydrate Program Expedition 01 (NGHP-01) is designed to study the occurrence of gas hydrate along the passive continental margin of the Indian Peninsula and in the Andaman convergent margin, with special emphasis on understanding the geologic and geochemical controls on the occurrence of gas hydrate in these two diverse settings. The NGHP-01 expedition established the presen
Authors
Timothy S. Collett, Ray Boswell, J. R. Cochran, Pushpendra Kumar, Malcolm Lall, Aninda Mazumdar, Mangipudi Venkata Ramana, Tammisetti Ramprasad, Michael Riedel, Kalachand Sain, Arun Vasant Sathe, Krishna Vishwanath

Molecular-level characterization of crude oil compounds combining reversed-phase high-performance liquid chromatography with off-line high-resolution mass spectrometry

A reversed-phase separation technique was developed in a previous study (Loegel et al., 2012) and successfully applied to the de-asphalted fraction of crude oil. However, to the best of our knowledge, the molecular-level characterization of oil fractions obtained by reversed-phase high-performance liquid chromatography (HPLC) coupled with high-resolution mass spectrometry (MS) has not yet been rep
Authors
Arum Sim, Yunju Cho, Daae Kim, Matthias Witt, Justin E. Birdwell, Byung Ju Kim, Sunghwan Kim

Simultaneous Gaussian and exponential inversion for improved analysis of shales by NMR relaxometry

Nuclear magnetic resonance (NMR) relaxometry is commonly used to provide lithology-independent porosity and pore-size estimates for petroleum resource evaluation based on fluid-phase signals. However in shales, substantial hydrogen content is associated with solid and fluid signals and both may be detected. Depending on the motional regime, the signal from the solids may be best described using ei
Authors
Kathryn E. Washburn, Endre Anderssen, Sarah J. Vogt, Joseph D. Seymour, Justin E. Birdwell, Catherine M. Kirkland, Sarah L. Codd

Paleogeomorphology of the early Colorado River inferred from relationships in Mohave and Cottonwood Valleys, Arizona, California and Nevada

Geologic investigations of late Miocene–early Pliocene deposits in Mohave and Cottonwood valleys provide important insights into the early evolution of the lower Colorado River system. In the latest Miocene these valleys were separate depocenters; the floor of Cottonwood Valley was ∼200 m higher than the floor of Mohave Valley. When Colorado River water arrived from the north after 5.6 Ma, a shall
Authors
Philip Pearthree, Kyle House

Fate of injected CO2 in the Wilcox Group, Louisiana, Gulf Coast Basin: Chemical and isotopic tracers of microbial–brine–rock–CO2 interactions

The “2800’ sandstone” of the Olla oil field is an oil and gas-producing reservoir in a coal-bearing interval of the Paleocene–Eocene Wilcox Group in north-central Louisiana, USA. In the 1980s, this producing unit was flooded with CO2 in an enhanced oil recovery (EOR) project, leaving ∼30% of the injected CO2 in the 2800’ sandstone post-injection. This study utilizes isotopic and geochemical tracer
Authors
Jenna L. Shelton, Jennifer C. McIntosh, Peter D. Warwick, Amelia Lee Zhi Yi

U.S. Geological Survey unconventional petroleum systems research in south Mississippi: Observations on burial history and thermal maturity in the Cretaceous

Shale hydrocarbon ‘resource’ plays have revolutionized the United States energy mix over the last 5 years. These plays are diverse in lithology and age but share the common feature of occurring in ‘tight’ formations which require hydraulic (hydro-) fracturing for economic flow rates. In general, economic success requires an organic-rich reservoir with a quartz- or carbonate-rich mineralogy that re
Authors
Paul C. Hackley, Brett J. Valentine, Catherine B. Enomoto, James L. Coleman

BET surface area distributions in polar stream sediments: Implications for silicate weathering in a cold-arid environment

BET surface area values are critical for quantifying the amount of potentially reactive sediments available for chemical weathering and ultimately, prediction of silicate weathering fluxes. BET surface area values of fine-grained (<62.5 μm) sediment from the hyporheic zone of polar glacial streams in the McMurdo Dry Valleys, Antarctica (Wright and Taylor Valleys) exhibit a wide range (2.5–70.6 m2/
Authors
Kristen R. Marra, Megan E Elwood Madden, Gerilyn S. Soreghan, Brenda L Hall

U-Pb zircon age data for selected sedimentary, metasedimentary, and igneous rocks from northern and central Alaska

This publication contains the complete results of U-Pb zircon age dating studies of sedimentary and metasedimentary units from northern and central Alaska that are discussed and interpreted in other reports by the author. Most of the U-Pb ages are of detrital zircons from sandstones, although U-Pb ages from igneous and sedimentary clasts from conglomerates in some of those same units are also incl
Authors
Thomas E. Moore

Stochastic modeling of a lava-flow aquifer system

This report describes preliminary three-dimensional geostatistical modeling of a lava-flow aquifer system using a multiple-point geostatistical model. The purpose of this study is to provide a proof-of-concept for this modeling approach. An example of the method is demonstrated using a subset of borehole geologic data and aquifer test data from a portion of the Calico Hills Formation, a lava-flow
Authors
Collin Cronkite-Ratcliff, Geoffrey A. Phelps

Vegetation controls on weathering intensity during the last deglacial transition in southeast Africa

Tropical climate is rapidly changing, but the effects of these changes on the geosphere are unknown, despite a likelihood of climatically-induced changes on weathering and erosion. The lack of long, continuous paleo-records prevents an examination of terrestrial responses to climate change with sufficient detail to answer questions about how systems behaved in the past and may alter in the future.
Authors
Sarah J. Ivory, Michael M. McGlue, Geoffrey S. Ellis, Anne-Marie Lézine, Andrew S. Cohen, Annie Vincens

Deformation from the 1989 Loma Prieta earthquake near the southwest margin of the Santa Clara Valley, California

Damage to pavement and near-surface utility pipes, caused by the 17 October 1989, Loma Prieta earthquake, provides evidence for ground deformation in a 663 km2 area near the southwest margin of the Santa Clara Valley, California (USA). A total of 1427 damage sites, collected from more than 30 sources, are concentrated in four zones, three of which lie near previously mapped faults. In one of these
Authors
Kevin M. Schmidt, Stephen D. Ellen, David M. Peterson