William E. Galloway

University of Texas at Austin | UT · Institute for Geophysics

Sediment routing from hinterland to the deep sea is complicated because it involves evolution of river drainage from source areas to coastal plains and sediment mixing on the shelf and slope by marine currents. Previous regional paleogeographic mapping in the Gulf of Mexico has observed a >150 km offset between the middle Miocene paleo-Tennessee fl...

It is well established that sedimentary margins grow by sediments bypassing through shelf- and slope-incising canyons onto the basin floor and by sediments being deposited incrementally across clinoforming and prograding margins. However, we argue that these two distinctive types of deep-water sediment supply to the basin floor and to the margin ar...

Highlights of DOI: 10.1111/bre.12659 Late Mesozoic Sandstone Volumes Recorded in Gulf of Mexico Subsurface Depocenters: Deciphering Long-Term Sediment Supply Trends and Contributions by Paleo-River Systems • Five Late Mesozoic paleo-rivers are deciphered from Gulf of Mexico subsurface depocenters • Siliciclastic grain volume over 12 Mesozoic supe...

Fluvial systems represent a key component in source-to-sink analysis of ancient sediment-dispersal systems. Modern river channels and channel-related deposits possess a range of scaling relationships that reflect drainage-basin controls on water and sediment flux. For example, channel-belt sand-body thicknesses scale to bankfull discharge, and repr...

Empirical scaling relationships between known deepwater siliciclastic submarine fan systems and their linked drainage basins have previously been established for modern to submodern depositional systems and in a few ancient, small-scale basins. Comprehensive mapping in the subsurface Gulf of Mexico basin and geological mapping of the North American...

This paper uses detrital zircon (DZ) provenance and geochronological data to reconstruct paleodrainage areas and lengths for sediment-routing systems that fed the Cenomanian Tuscaloosa-Woodbine, Paleocene Wilcox, and Oligocene Vicksburg-Frio clastic wedges of the northern Gulf of Mexico (GoM) margin. During the Cenomanian, an ancestral Tennessee-Al...

In past decades, numerous studies have focused on the alluvial sedimen-tary record of basin fill. Paleo–drainage basin characteristics, such as drainage area or axial river length, have received little attention, mostly because the paleo–drainage system underwent erosion or bypass, and its record is commonly modified and overprinted by subsequent t...

The early Miocene was a period of major continental margin progradation in the Gulf of Mexico Basin that accompanied prominent tectonic and climatic changes in North America. However, sediment pathways from continental upland sources to deep basinal sinks remain poorly constrained. This study presents 2192 new detrital zircon U-Pb analyses from 19...

The recurrence of the same types of sequence stratigraphic surface through geologic time defines cycles of change in accommodation or sediment supply, which correspond to sequences in the rock record. These cycles may be symmetrical or asymmetrical, and may or may not include all types of systems tracts that may be expected within a fully developed...

The Cenozoic fill of the Gulf of Mexico basin contains a continuous record of sediment supply from the North American continental interior for the past 65 million years. Regional mapping of unit thickness and paleogeography for 18 depositional episodes defines patterns of shifting entry points of continental fluvial systems and quantifies the total...

Sequence stratigraphy emphasizes changes in stratal stacking patterns in response to varying accommodation and sediment supply through time. Certain surfaces are designated as sequence or systems tract boundaries to facilitate the construction of realistic and meaningful palaeogeographic interpretations, which, in turn, allows for the prediction of...

This paper mainly discusses the origin and depositional features of fan‐deltas and braid deltas. Fan‐deltas are storm discharge‐dominated, while braid deltas are usually flashy flood‐dominated. The two types of delta, like common deltas, were reworked by marine processes. Delta systems are classified into nine delta types on the.basis of. the subae...

We thank William Helland-Hansen for his compliments and feedback on our paper. We aimed to establish a consensus in sequence stratigraphy by using a neutral approach that focused on model-independent, fundamental concepts, because these are the ones common to various approaches. This search for common ground is what we meant by “standardization,” n...

SummaryA comprehensive synthesis of the Cenozoic depositional history of the Gulf of Mexico basin has integrated data from the coastal plain, shelf, slope and deep basin. Twenty widely recognized Cenozoic genetic-stratigraphy sequences record major and minor depositional episodes of the northern Gulf basin. Results of this synthesis provide a pictu...

Sequence stratigraphy emphasizes facies relationships and stratal architecture within a chronological framework. Despite its wide use, sequence stratigraphy has yet to be included in any stratigraphic code or guide. This lack of standardization reflects the existence of competing approaches (or models) and confusing or even conflicting terminology....

The Gulf of Mexico is a small ocean basin lying between the North American Plate and the Yucatan block. It contains within its depocenter a succession of Jurassic through Holocene strata that is as much as 20 km thick. Sediment supply from the North American continent has filled nearly one-half of the basin since its inception, primarily by of ap o...

The Gulf of Mexico is a small ocean basin lying between the North American plate and the Yucatan block. Following initiation in the Middle Jurassic, sea-floor spreading continued approximately 25Myr. Spreading was asymmetric, creating a broad area of attenuated transitional continental crust beneath the northern basin. Initially, widespread, thick...

In the Gulf of Mexico (GOM), an extensive deep-water fan system of the lower Tertiary Wilcox Group forms a significant exploration target, yet connections to equivalent-aged onshore fluvial, deltaic, and shallow-marine reservoirs are poorly documented. Using a large, three-dimensional (3-D) seismic survey (3300 mi(2), 8500 km(2)), we examined the l...

A shallow coring and geophysical logging program has recorded the sedimentary fill of the Brazos River valley in the Texas Gulf Coastal Plain. Thermoluminescence dates together with new and recalibrated published radiocarbon dates show the valley fill to include extensive, sandy, buried falling stage and lowstand Oxygen Isotope Stage (OIS) 3 and 2...

The Queen City Formation (Eocene) displays an array of tide-dominated coastal facies in the Tyler Basin of the northern Gulf of Mexico. This facies assemblage, which is atypical of the microtidal, wave-dominated, coastal depositional complexes that characterize the Cenozoic Gulf basin, reflects tidal amplification in a generally protected embayment...

A regional stratigraphic and structure framework has been established for the middle Miocene sediment-depositional episode from the shelf through the slope to the basin floor for the east-central Gulf of Mexico. Two widespread, transgressive deposits associated with the faunal tops Amphistegina B (15.5 Ma) and Textularia W (12.1 Ma) define the midd...

Winker (1982; 1984) provided the first summary overview of the depositional evolution of the Gulf of Mexico continental margin, along with a suite of criteria for margin recognition. The subsequent more than 20 years of exploration deep drilling in the Gulf has substantiated both his methodology and synthesis. This paper updates Winker’s map and lo...

A regional analyses to develop sand dispersal models of the Gulf basin is discussed. The Cenozoic sedimentary prism of the northern Gulf consists of offlapping, sigmoidal, sedimentary sequences deposited by a succession of depositional episodes. Two key acquisition parameters are maximized in order to better image the steep flanks of salt bodies as...

The upper Miocene (late middle to early late Miocene) depositional episode (UM depisode) records a long-lived family of sediment dispersal systems that persisted for nearly 6 Ma with little modification. In the central Gulf of Mexico basin, this depisode records extensive margin offlap, primarily centered on the paleo-Tennessee River and Mississipp...

The middle-late Miocene Utsira sandstone of the North Sea Basin contains a fully preserved, regional marine sand deposit that records a stable paleogeographic setting of shelf sand transport and accumulation within an epeiric shelf sea which persisted for ca. 8 Myr. The sediment dispersal system was defined by (1) sediment input through a progradin...

Sequence stratigraphic application has emphasized the recognition and use of subaerial (fluvial entrenchment) or shallow marine/shoreface (regressive ravinement) surfaces as critical boundaries for defining sequences. These surfaces are variously objectively or conceptually associated with times of onset, maximum rate, and/or lowest position of rel...

Paleogeographic and volumetric lithofacies mapping of 18 Cenozoic genetic sequences within the Northern Gulf of Mexico Basin quantifies the proportional sequestering of sediment within wave-dominated shore-zone vs. deltaic systems through time. Three long-term depositional phases are revealed by plots, based on paleogeographic and sediment isochore...

The Middle–Late Miocene Utsira Formation of the North Sea Basin contains a fully preserved, regional marine sand deposit that records a stable paleogeographic setting of sand transport and accumulation within a deep, epeiric seaway which persisted for >8 Ma. The sediment dispersal system was defined by (1) input through a marginal prograding strand...

A Geographic Information System (GIS) database incorporating information from 241 publications, theses, and dissertations; well logs and paleontologic reports; and interpreted University of Texas Institute for Geophysics (UTIG) deep-basin seismic lines was used to map and interpret 18 basinwide genetic stratigraphic sequences that form the Gulf of...

In Stratigraphic Systems: Origin and Application, Glenn S.Visher attempts to synthesize and organize the knowledge and integrated interpretation system developed over 35 years in sedimentary analysis. The book sets forth an extremely aggressive agenda: to bring together a knowledge base that includes basin tectonics, stratigraphy, sedimentology pal...

Hydrologic processes are fundamental in the emplacement of all three major categories of sedimentary uranium deposits: syngenetic, syndiagenetic, and epigenetic. In each case, the basic sedimentary uranium-enrichment cycle involves: (1) leaching or erosion of uranium from a low-grade provenance; (2) transport of uranium by surface or groundwater fl...

The Gulf of Mexico continues to be a premier basin for global hydrocarbon exploration and development. An overwhelming volume of information has been generated by decades of onshore and offshore seismic acquisition and drilling. A major challenge facing explorationists is the synthesis of this information into a framework that can focus efforts in...

Subaqueous slope and base-of-slope depositional systems are a major component of most marine and many lacustrine basin fills, and constitute primary targets for hydrocarbon exploration and development. Seven basic facies building blocks comprise slope systems: (1) turbidite channel fills, (2) turbidite lobes, (3) sheet turbidites, (4) slide, slump,...

Sediment supply comprises a major family of regime variables that influence geomorphic surface grade. Spatial and temporal changes in total sediment supply and sediment texture (gravel:sand:mud ratio) will cause reconfiguration of clepositional and erosional profiles, potentially creating or influencing the sequence stratigraphic framework of the b...

Short-term variations in accommodation and sediment supply on the continental shelf cause imbalances within longer-term dynamic equilibrium conditions. These imbalances result in the deposition of high-frequency sequences. The Eocene Yegua Formation of the Texas Gulf Coast is made up of six such sequences, which have average durations of 0.8 millio...

Slope and base-of-slope depositional systems (simply called slope systems for brevity) occur in relatively deep water beyond the shelf break. However, the meaning of “deep” depends upon basin type and tectonic context. On modern continental margins the shelf break typically lies at depths of 90–180m (300–600ft), but in intracratonic, foreland, and...

Coal-forming environments have waxed and waned in extent since the mid-Paleozoic, having been associated with a restricted range of environments and hydrologic regimes during relatively brief geologic timespans. The three major episodes of coal genesis were the late Carboniferous and Permian, the late Jurassic through early Cretaceous, and the late...

Although a discussion of hydrogeologic processes and basinal flow systems may seem to be a departure from this examination of depositional systems, it is included for several compelling reasons.

Terrigenous shelves include both epeiric (epicontinental) platforms and continental shelves with a mantle of land-derived sediments. Epeiric platforms are broad, shallowly inundated continental areas. Modern examples such as the North Sea, Hudson Bay, and Gulf of Carpentaria are small by comparison with many of their ancient counterparts. Continent...

Studies of eolian systems have been spurred by their association with hydrocarbons, for example in the Permian Rotliegendes of the North Sea, the Jurassic of the Gulf of Mexico and western United States, and elsewhere. In other geologic situations, they host epigenetic and placer minerals of commercial importance. Although commonly not as thick as...

A delta forms where a river transporting significant quantities of sediment enters a receiving basin. In one sense, few processes or environments are unique to the deltaic setting. However, the interaction of subaerial fluvial processes and subaqueous processes of marine or lake basins produces distinctive facies assemblages. A delta is a progradat...

Alluvial fans are conical, lobate, or arcuate accumulations of sediment that have a focused source of sediment supply, usually an incised canyon or channel from a mountain front or escarpment. Fans are depositional geomorphic features, defined by their point source, equidimensional planview geometry, mounded topographic profile, and radial sediment...

Most of the world’s energy and groundwater resources are in sedimentary rocks, and any procedure that helps to categorize, understand, and predict the external geometry, internal architecture, and other properties of sedimentary rocks can contribute to more efficient discovery, exploitation, and resource management. The depositional systems approac...

Fluvial systems primarily collect and transport sediment into lacustrine or marine basins. However, in certain basin settings favoring subaerial accumulation of sediment, such as subsiding coastal plains, intermontane basins, and tectonic forelands, fluvial depositional systems may become a major or even dominant component of the basin fill. Even w...

Lacustrine systems have assumed new importance with the growing recognition that they contain some of the richest oil-prone source rocks, which in many extensional basins are located in zones of high thermal maturation, in close proximity to porous synrift or postrift reservoirs. Rift-basin lake systems underlie many passive-margin basins, where th...

Quantitative analysis of sediment supply rate, subsidence and uplift rates, and eustatic sea-level change demonstrates order of magnitude changes in the ratios of these regime variables over timespans of tens of thousands to a few million years. This chapter focuses on the results of this history of change — the punctuated accumulation of depositio...

Although not a fossil fuel, uranium shares with petroleum and coal many similarities in geologic origin, mode of occurrence, and utilization. Existing fission reactors consume 235U, producing waste byproducts of the induced fission process. It is noteworthy that less than 1% of naturally occurring uranium is the desired 235U isotope, the remainder...

The shore zone, excluding deltas, comprises the narrow, high-energy transitional environment that extends from wave base, commonly at about 10 m (35 ft) to the landward limit of marine processes (Fig. 6.1). Although the shore zone is a narrow, linear zone, shorelines migrate over time to leave a record of widespread shore-zone deposits, with consid...

A trend in applied facices sedimentology during the late the twentieth century is the shift in focus from hydrocarbon exploration, with its need for reservoir prediction and extrapolation, to detailed reservoir characterization. As many older oil and gas fields reach maturity, they must be redeveloped and advanced production technologies applied if...

The real world is immensely complex (and) continuous. Isolated structures are therefore subjective and artificial portions of reality, and the biggest initial problem is the identification and separation of meaningful sections of the real world. On the one hand, every section or structure must be sufficiently complex … so that its study will yield...

For the industrial nations of the world, petroleum has fueled the twentieth century. Despite accelerating depletion of the resource, new technologies and exploration concepts are contributing to effective replacement of production, and oil and gas will remain major contributors to the world energy supply well into the next century. Because the disc...

This second edition bridges the gap between process-related out-crop studies of sedimentary rocks and the three-dimensional subsurface world of the mineral fuel geologist and hydrogeologist. It remains unique in its focus on the application of subsurface facies analysis to problems of petroleum, coal, uranium, and ground water resource discovery, d...

Detailed correlation using well logs combined with seismic data shows that the Miocene succession of central Texas and western Louisiana are highly cyclic. These cycles are vertically stacked to form a hierarchy with durations ranging from 0.4 my. to 2.0 my. Previous quantitative testing of the high-frequency cyclicity in central Texas suggested th...

The middle Wilcox subgroup in the Texas coastal plain of the Gulf of Mexico basin is consistently defined by maximum flooding surfaces associated with the Big shale at the bottom and the Yoakum shale at the top, dated at 56.5 Ma and 54.3-55.0 Ma, respectively. Two high-resolution genetic stratigraphic sequences of the middle Wilcox were delineated...

The Lavaca submarine canyon briefly formed a large slump-generated embayment, centered in Lavaca County, Texas, along the prograding Lower Wilcox shelf margin. Episodes of canyon excavation by large-scale mass wasting alternated with periods of delta lobe progradation into the upper canyon. Resultant canyon fill consists of: 1) displaced, rotated s...

Slope/basin depositional systems consist of combinations of facies, including slump lobes; chute, flute, and channel fills; mounded turbidite lobes; sheet turbidites; low-density turbidite sheets and fills; hemipelagic drapes; and contourite mounds. Specific facies associations are determined by the nature (point source or linear source) and calibe...

The lower Wilcox (LW) strata comprise a single genetic sequence and are subdivided into four subsequences (I-IV, from oldest to youngest) based on regional flooding surfaces. The LW sequence is bounded by maximum flooding surfaces associated with the Big Shale at the top and Midway marine shale at the bottom, and is dated at 56.5 Ma and 59.0 Ma. Th...

The Qingshankou, Yaojia, and Nenjiang (QYN) formations in the Songliao basin of northeastern China can be used to illustrate the application of sequence stratigraphic analysis in a lacustrine setting and to provide a good example of hydrocarbon occurrence in a lacustrine stratigraphic framework. The QYN genetic stratigraphic sequence, bounded by ma...

The post-Danian through Miocene clastic fill of the Central and Northern North Sea Basin consists of four tectonosequences that record the regional structural evolution of the basin and adjacent source areas. The tectonosequences, in turn, contain strata deposited during at least 15 depositional episodes, creating a series of stratigraphic sequence...

High-frequency glacioeustatic sea-level change is one of the major factors that controls late Paleogene and Neogene clastic sedimentation. Study of such high-frequency cyclicity will greatly improve the understanding of reservoir stratification and compartmentalization. Quantitative testing of these high-frequency cycles of Milankovitch periodicity...

There are errors associated with the sediment-accumulation rates determined from either present thickness or decompacted thickness due to compaction. We propose to use solid grain thickness to calculate sediment-accumulation rates so as to remove the compaction effects. Using this approach, we analyzed the sediment accumulation rates for North Sea...

Eocene siliciclastics of the North Sea Basin have been divided into five stratigraphic sequences regionally correlated on reflection seismic and well log data. These include: a sand-rich, onlapping lower Eocene unit; two middle Eocene mud-prone outbuildings from the Moray Firth area; a middle to upper Eocene basin-centered amalgamation of muddy and...

The evolution of continental margins and related distribution of hydrocarbon reservoirs in divergent margin basins reflects the primary interaction between sediment supply and process regime within the basin and secondary modifications by sea-level change and structural history. Cenozoic sequences of the northwestern Gulf Coast Basin contain numero...

The Paleogene fill of the northwestern Gulf of Mexico basin consists of eight genetic stratigraphic, sequences bounded by regional marine flooding surfaces. Calculation of sediment accumulation rates along dip profiles through four subbasins shows that regional changes in accumulation rate---and by inference, rate of sediment supply---of fivefold t...

The late Paleocene Yoakum/Lavaca submarine canyon system exhibits morphologies and fill patterns typical of canyons cut in prograding continental margins. Initially, canyons were excavated largely by retrogressive slumping of unstable sediments of the flank of the Wilcox deltaic platform. Given sufficient time and extensive submergence of the depos...

The Yoakum canyon is the largest of the Gulf Coast Eocene erosional gorges and is interpreted as a buried submarine channel. The canyon can be traced for 67 mi (108 km) from the Wilcox fault zone, which defines the position of the early Eocene shelf edge, nearly to present outcrop. In this paper, the authors expand on previously published descripti...