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USGS2026

Paleocene-Eocene dinoflagellate biostratigraphy in the central Delaware coastal plain

Dinoflagellate cyst palynology and lithostratigraphy from three continuously cored boreholes (Blackbird, Smyrna, and Woodland Beach), supplemented by calcareous nannofossil biostratigraphic data, were used to refine the age and correlation of three Paleocene-Eocene formations in northern Delaware: the Vincentown, Manasquan, and Shark River. Lithologic logs reveal significant facies changes in the upper Paleocene Vincentown Formation over a short distance (*9 km) southeastward, transitioning from very permeable glauconite-quartz-shell-rich sands that form the regionally important Rancocas/Aquia aquifer to much less permeable muddy sands and sandy muds. These lithologic changes represent a shift from nearshore, clear, warm-water, carbonate-rich sand shoals to mud-dominated deeper-water, offshore shelfal environments. Dinocyst assemblages including Areoligera gippingensis, Cribroperidinium giuseppei, and Stenodinium meckelfeldensis confirm the Paleogene ages and track these paleoceanographic changes from shallow coastal settings updip to neritic or outer marine settings downdip. The Vincentown Formation is unconformably overlain by the lower Eocene Manasquan Formation, which consists predominantly of silt and clay with relatively consistent lithology across the study area, representing general neritic or open marine conditions. Lithology, dinoflagellate cyst assemblages, and calcareous nannofossil data indicate that the Marlboro Clay and its record of the onset of the Paleocene-Eocene Thermal Maximum (PETM) global warming event is absent from the Paleocene-Eocene transition at these sites, with an unconformity marking the boundary between the Vincentown and Manasquan formations. The youngest unit examined, the Eocene Shark River Formation, unconformably overlies the Manasquan Formation and consists of interbedded clayey silts and sands, with dinoflagellate assemblages suggesting a return to coastal or inner neritic settings. Calcareous nannofossil zones recognized from the Woodland Beach core corroborate the depositional ages determined using dinoflagellates throughout the sequence, confirming the chronostratigraphic framework for these important coastal plain units.

Delaware↗

USGS1996

Pliocene–Pleistocene pollen assemblages from the Yermak Plateau, Arctic Ocean: Sites 910 and 911

Palynological and paleobotanical research on upper Pliocene sediments from Meighen Island, Kap København, and deep-sea sites in the North Atlantic Ocean has indicated the presence of forest tundra far north of its present limits and warmer conditions than present. New pollen data from samples obtained on Ocean Drilling Program Leg 151 (Sites 910 and 911) on the Yermak Plateau of the Arctic Ocean provide a record of late Pliocene terrestrial floras characteristic of at least boreal to subarctic climatic conditions in the source areas. Pollen and spores are present in upper Pliocene sediments from both cores, with typical concentrations of 1,000 to 2,000 pollen grains per gram of dry sediment. Pinus is the dominant genus in upper Pliocene assemblages, and Picea and Betula are subdominant. Other taxa typically present include Alnus , Corylus , Larix , Tsuga , Pterocarya , Sciadopitys and members of the Poaceae, Cyperaceae, Asteraceae, and Ericaceae. These assemblages are suggestive of open boreal vegetation with relatively temperate deciduous elements and indicate warmer Pliocene conditions than today in the pollen source areas. Pleistocene pollen assemblages from Site 911 consist primarily of Pinus and Picea pollen with few other taxa present. Such assemblages indicate cold conditions, probably similar to those of today, and palynomorphs are less common in Pleistocene sediments, typically <1,000 pollen grains per gram of dry sediment. In both cores, most reworked palynomorphs, which are two to three times more abundant than nonreworked ones, are Cretaceous in age and include genera characteristic of both the Aquilapollenites and Normapolles provinces; this composition suggests that the source of reworked material was the northern Asian coast between the Barents Sea and Laptev Sea, the main region where Cretaceous rocks containing both these assemblages are preserved. These reworked palynomorphs probably were transported either by sea ice or ocean currents via the Transpolar Drift to the Yermak Plateau sites.

Conference Paper↗

USGS2004

Geologic map of the Kanab 30' x 60' quadrangle, Utah and Arizona

The 1:100,000-scale geologic map of the sparsely populated Kanab 30' x 60' quadrangle in southernmost Utah and a narrow strip in northernmost Arizona delineates 17 formations and numerous subdivisions of sedimentary rock units of Permian, Triassic, Jurassic, Cretaceous, and Tertiary ages; 12 Quaternary alluvial, eolian, and mass-wasting units; and Quaternary basaltic igneous rocks and vents.Units within the Straight Cliffs Formation are correlated with those of the Kaiparowits Plateau. Palynological edidence indicates that the Kaiparowits(?) Formation is older than the type formation in the Kaiparowits Plateau. Structures include parts of the Sevier, Kanab Creek, Johnson Canyon, and Paunsaugunt fault zones. Regional dip is generally northeast at very low angles. Coal beds are presentin the upper unit of the Straight Cliffs Formation, in the Tropic Shale, and in the Dakota Formation.

IMAP↗

USGS2006

Micropaleontology of selected wells and seismic shot holes, northern Alaska

This report provides micropaleontologic data (foraminifera, pollen, spores, and microplankton) and interpretations of the rocks penetrated by 49 wells and 3,134 seismic shot holes distributed among 73 seismic lines (figs. 1, 2; table 1). All shot holes and 30 wells are located within the National Petroleum Reserve in Alaska (NPRA); the remaining 19 wells are located adjacent to the NPRA. The biostratigraphic zonation scheme, stratigraphy, and geologic ages followed in this study are summarized in figure 3. This update brings paleontologic analyses performed at various times over several decades to a current, unified set of interpretations that benefit from the evolution of northern Alaska biostratigraphic understanding developed during the past 33-years by Mickey and Haga. For each well, paleontologic information includes microfossil distribution charts, data spreadsheets, diversity graphs, and interpretive reports describing age and environments of deposition. Three biostratigraphic well-correlation sections that relate Chukchi Sea wells to onshore northwestern NPRA wells are also included. For all analyzed seismic shot hole samples, foraminiferal age and environmental interpretations are provided; palynological interpretations are provided only for those shot hole samples collected and analyzed after 1976, a little less than half of the total number of samples.

Open-File Report↗

USGS2006

Review of lignite resources of western Tennessee and the Jackson Purchase area, western Kentucky

Introduction: This review of the lignite deposits of western Tennessee and the Jackson Purchase area in western Kentucky (Fig. 1) is a preliminary report on part of the U.S. Geological Survey's National Coal Resource Assessment of the Gulf Coastal Plain Coal Province. Lignite deposits of western Kentucky and Tennessee are an extension of the Gulf Coastal Plain Coal Province (Cushing and others, 1964), and currently are not economic to mine. These deposits have not been extensively investigated or developed as an energy resource. This review includes a description of the geology of the lignite-bearing units, a discussion of the available coal quality data, and information on organic petrology. Palynological data for lignite samples collected in Kentucky and Tennessee as part of this work are presented in an Appendix.

Open-File Report↗

USGS2006

Analytical results from samples collected during coal-bed methane exploration drilling in Caldwell Parish, Louisiana

In 2001, and 2002, the U.S. Geological Survey (USGS) and the Louisiana Geological Survey (LGS), through a Cooperative Research and Development Agreement (CRADA) with Devon SFS Operating, Inc. (Devon), participated in an exploratory drilling and coring program for coal-bed methane in north-central Louisiana. The USGS and LGS collected 25 coal core and cuttings samples from two coal-bed methane test wells that were drilled in west-central Caldwell Parish, Louisiana. The purpose of this report is to provide the results of the analytical program conducted on the USGS/LGS samples. The data generated from this project are summarized in various topical sections that include: 1. molecular and isotopic data from coal gas samples; 2. results of low-temperature ashing and X-ray analysis; 3. palynological data; 4. down-hole temperature data; 5. detailed core descriptions and selected core photographs; 6. coal physical and chemical analytical data; 7. coal gas desorption results; 8. methane and carbon dioxide coal sorption data; 9. coal petrographic results; and 10. geophysical logs.

Open-File Report↗

USGS2007

Analysis of the dinoflagellate cyst genus Impletosphaeridium as a marker of sea- ice conditions off Seymour Island: An ecomorphological approach

A unique reworked palynological assemblage composed of 32 to 100% (average of 63%) in Impletosphaeridium spp., was found during the study of sixteen samples recovered from piston cores taken off Seymour Island, Antarctica, during a pre-SHALDRIL study. One of the common Impletosphaeridium species recovered, I. lorum, was previously found in Seymour Island’s La Meseta Formation. Two questions we asked are: “What is the age of this high abundance of Impletosphaeridium spp., providing that they come from a unique source?”, and second “What is the environmental significance of such a high relative abundance?” The samples are likely to have been derived from sediments ranging from Eocene to Miocene in age, as this is the range for most of the Impletosphaeridium species. The environmental significance of this high abundance is a difficult question, not only because the genus is extinct, but also because these species are poorly known. To try to understand the ecological significance, we used the hypothesis that the morphology of a dinocyst is linked to environmental sea-surface parameters, and looked at extant species with a similar morphology. The extant dinoflagellate cysts of Echinidinium spp, Islandinium cezare, Islandinium minutum, and Pentapharsodinium dalei were selected for their morphological similarity with Impletosphaeridium. Modern ecological parameters for the extant species listed above were derived from the DinoDatabase (940 modern sea-surface samples from around the world). The database showed that these species are all indicators of sea-ice cover, with a minimum of 8 months for Echinidinium spp., ~ 5 months for Islandinium cezare, and from 1 to 12 months for Pentapharsodinium dalei and Islandinium minutum. If our morphologic-similarity hypothesis is correct, and if this high abundance is indeed indicative of a paleo-environmental condition, then it is most likely to have been associated with ephemeral sea-ice development off Seymour Island, sometime between the Eocene and the Miocene.

Open-File Report↗

USGS1966

Plant microfossils from the Fort Union Formation

As a part of continuing studies to provide palynological data from critical sequences for comparative biostratigraphic studies, the microfossils found in two Paleocene samples have been examined and photographed.

Open-File Report↗

USGS1966

Geology of the Cerro Summit quadrangle, Montrose County, Colorado

The Cerro Summit quadrangle covers 58 square miles of dissected plateau on the south flank of the Gunnison uplift in southwestern Colorado. It lies east of the Uncompahgre River valley and south of the Black Canyon of the Gunnison River. Rocks dip gently in most of the quadrangle, but they are locally upturned and faulted on the margin of the Gunnison uplift and are intensely deformed in the core of the uplift. The rocks exposed are of Precambrian, late Mesozoic, and Cenozoic age. Precambrian rocks include metasedimentary schist and gneiss, granitic pegmatite, and olivine gabbro. The oldest Mesozoic rocks exposed are continental, fresh-water, and lagoonal deposits in the Late Jurassic Entrada Sandstone, Wanakah Formation, and Morrison Formation. Channel-fill deposits that unconformably overlie the Jurassic rocks are possibly the Burro Canyon Formation of Early Cretaceous age. Upper Cretaceous rocks include marine and nearshore deposits of the Dakota Sandstone, Mancos Shale, and Pictured Cliffs Sandstone, and the fresh- and brackish-water sandstone, shale, and coal of the Fruitland Formation. Rocks of Late Cretaceous age that crop out in the adjacent Cimarron Ridge area may also have been deposited in this quadrangle but are now eroded; these rocks include the nonmarine Kirtland Shale and an unnamed volcanic conglomerate and tuff breccia. Nine faunal zones in the Mancos Shale help to establish the correct correlation of units in the Upper Cretaceous. The Pictured Cliffs Sandstone, Fruitland Formation, and Kirtland Shale of the Cerro Summit area have been mapped by some geologists as the Mesaverde Formation. Fossils indicate that the rocks are younger than the type Mesaverde. The unnamed volcanic rocks represent major volcanism in nearby areas. A Late Cretaceous (Maestrichtian) age for the volcanism is indicated by palynological evidence and an isotopic age of approximately 66 million years. Middle Tertiary rocks are conglomerate and tuff breccia. Upper Tertiary or lower Quaternary rocks include gravel along Pool Gulch and older landslide debris on Waterdog Peak. Pleistocene and Recent deposits consist of the older stream gravel of Shinn Park, valley-fill deposits of Bostwick-Shinn Park, and pediment, landslide, eolian, alluvial, and colluvial deposits. P1elstocene valley-fill deposits of Bostwick-Shinn Park were deposited during the Cedar Ridge, or Kansan, to Pinedale or late Wisconsin times. The valley-fill deposits are divided into five units that are separated by strong Interglacial or Interstadial soils and that contain three volcanic ash beds. Chemical and petrographic data suggest that the middle ash bed may correlate with the Pearlette Ash Member (late Kansan) of the Sappa Formation in Nebraska. Alluvium on two pediment surfaces seems to be of Sacagawea Ridge or Illinoian age. Landslide deposits, of Pleistocene and Recent age, cover about 85 percent of the quadrangle; most of the deposits were formerly mapped as till. The name Cerro Till was abandoned because till does not occur in the type area. The dominant tectonic structures are the high-angle Cimarron fault of a few thousand feet displacement and the broad Montrose syncline. Evidence in the Cimarron Ridge area suggests that these structures formed in Late Cretaceous (Maestrichtian) time. Much of the strata near the surface of the quadrangle has been involved in landsliding that has continued from late Tertiary to the present.

Open-File Report↗

USGS1983

Reconnaissance geologic map of the Harrat Tuffil Quadrangle, sheet 20/39 B, Kingdom of Saudi Arabia

The Harrat Tuffil quadrangle, sheet 20/39 B, is located between lat 20°30’ and 21°00’ N. and long 39°30’ and 40°00’ E. about 50 km southeast of Jiddah. A western belt of Proterozoic metapelites and related rocks, defined as the Sa’diyah formation, structurally underlies and locally is interlayered with Proterozoic metabasaltic rocks of oceanic chemical affinity to the east. The Sa’diyah formation and the metabasaltic rocks are tentatively correlated with the Sabya formation and Baish group. These rocks may represent a miogeosynclinal tectonic setting in the 800 to 850 Ma period of development of the southwestern Arabian Shield. The presence of aluminous metasediments suggest a continental source area, probably west of oceanic and (or) immature island-arc rocks of the Baish(?) igneous suite. The Sa’diyah formation and metabasaltic rocks are intruded by a granite gneiss batholith, probably about 600 Ma old, and by small plutons of granodiorite and syenogranite. Peraluminous monzogranite occurs within the western part of the Sa’diyah formation belt and may provide an alternate source for the aluminous politic rocks. Tentative correlation of an isolated exposure of Jurassic(?) dolomite with the Hanifa Formation significantly extends the areal range of possible Jurassic sedimentary rocks in the Tihamat province. An intense dike swarm intrudes all of the pre-Miocene rocks in the quadrangle. This Damm dike complex is named for Wadi ad Damm. Dike chemistry shows both subalkaline and alkaline bimodal suites. The Sita formation is broadly coeval with the Damm Dike complex and contains volcanic rocks with similar bimodal chemistry. The Sita formation conformably overlies and is locally interbedded with the Sumaysi formation, which is palynologically dated in the Makkah quadrangle as Eocene (~50 Ma). Potassium-argon dating indicated intrusion and volcanism over the period ~50Ma to ~20 Ma ago. The Tertiary volcanic, hypabyssal, and plutonic rocks are all light rare-earth element enriched as would be expected in a rift-related tectonic setting. These rocks represent proto-Red Sea igneous activity and are correlated with the Jizan group. Shama rhyolite near Harrat Tuffil is unconformably overlain by a boulder conglomerate correlated with the Bathan formation. Miocene alkali basalt forms a large paleovalley-fill lava flow at Harrat ad Damm and small flow remnants north of Jabal Sita. Erosional downcutting at Harrat ad Damm averaged ~10 m per MA over the past 11 Ma. Pliocene alkali basalt unconformably overlies Bathan formation and Shama rhyolite at Harrat Tuffil. The uplift of Quaternary reef limestone along the Red Sea coast indicates recent faulting as shown in the adjoining Shu’ayba and Al Ghalah quadrangles. A perlite deposit at Jabal Shama may be suitable as light aggregate for concrete. Sparse barite veins were discovered in the lower Shumaysi formation. Relatively small deposits of Sa’diyah formation marble may be of interest for local use in building or cement. The Jurassic dolomite is locally quite pure and may have economic applications.

Open-File Report↗

USGS1995

Coal geology of the Paleocene-Eocene Calvert Bluff Formation (Wilcox Group) and the Eocene Manning Formation (Jackson Group) in east-central Texas: Field trip guidebook for the Society for Organic Petrology, Twelfth Annual Meeting, The Woodlands, Texas, August 30, 1995

The Jackson and Wilcox Groups of eastern Texas (fig. 1) are the major lignite producing intervals in the Gulf Region. Within these groups, the major lignite-producing formations are the Paleocene-Eocene Calvert Bluff Formation (Wilcox) and the Eocene Manning Formation (Jackson). According to the Keystone Coal Industry Manual (Maclean Hunter Publishing Company, 1994), the Gulf Coast basin produces about 57 million short tons of lignite annually. The state of Texas ranks number 6 in coal production in the United States. Most of the lignite is used for electric power generation in mine-mouth power plant facilities. In recent years, particular interest has been given to lignite quality and the distribution and concentration of about a dozen trace elements that have been identified as potential hazardous air pollutants (HAPs) by the 1990 Clean Air Act Amendments. As pointed out by Oman and Finkelman (1994), Gulf Coast lignite deposits have elevated concentrations of many of the HAPs elements (Be, Cd, Co, Cr, Hg, Mn, Se, U) on a as-received gm/mmBtu basis when compared to other United States coal deposits used for fuel in thermo-electric power plants. Although regulations have not yet been established for acceptable emissions of the HAPs elements during coal burning, considerable research effort has been given to the characterization of these elements in coal feed stocks. The general purpose of the present field trip and of the accompanying collection of papers is to investigate how various aspects of east Texas lignite geology might collectively influence the quality of the lignite fuel. We hope that this collection of papers will help future researchers understand the complex, multifaceted interrelations of coal geology, petrology, palynology and coal quality, and that this introduction to the geology of the lignite deposits of east Texas might serve as a stimulus for new ideas to be applied to other coal basins in the U.S. and abroad.

Texas↗

USGS1980

Sporomorphs from the Jackson Group (upper Eocene) and adjacent strata of Mississippi and western Alabama

This palynological study is based on 71 outcrop and core samples of the Jackson Group and adjacent strata from the type area of the group in western Mississippi and also from eastern Mississippi and western Alabama. The Jackson Group consists entirely of marine strata in the region of study. It includes the fossiliferous greensands of the Moodys Branch Formation at the base and the calcareous Yazoo Clay at the top. One hundred seventy-four sporomorph (spore and pollen) types are known from the Jackson Group and adjacent strata in the area of study; all but four of them were observed by the writer. The 174 types are assigned to 74 form genera, 37 modern genera, and 25 new species. Eleven species of pollen grains appear to have accurately determined restricted stratigraphic ranges within the sequence studied. Parsonsidites conspicuus Frederiksen and Ericipites aff. E. ericius (Potonie) Potonie have first occurrences (range bottoms) at the base of the Jackson Group. Aglaoreidia pristina Fowler has its first occurrence near the top of the Jackson. Eight species have last occurrences at or just below the top of the Jackson Group. These are Casuarinidites cf. C. granilabratus (Stanley) Srivastava, Chrysophyllum brevisulcatum (Frederiksen) n. comb., Cupanieidites orthoteichus Cookson and Pike, Symplocos gemroota n. sp., Nudopollis terminalis (Pflug and Thomson) Elsik, Sabal cf. S. granopollenites Rouse, Caprifoliipites tantulus n. sp., and Nypa echinata (Muller) n. comb. From the upper part of the Claiborne Group up through most of the Jackson, the dominant sporomorph types are Cupuliferdipollenites spp., Momipites coryloides Wodehouse, Cupuliferoidaepollenites liblarensis (Thomson) Potonie, Momipites micTofoveolatus (Stanley) Nichols, Quercoidites microhenricii (Potonie) Potonie, and Araliaceoipollenites granulatus (Potonie) n. comb. All these were probably produced by trees of the Juglandaceae and Fagaceae. Relative frequencies of each of these pollen types fluctuate little within the interval from the upper part of the Claiborne to near the top of the Jackson. Near the top of the Jackson Group, there is a rapid rise to dominance or near dominance of the sporomorph assemblages by Quercoidites inamoenus (Takahashi) n. comb. (Fagaceae, Dryophyllum or Quercus). This remains the dominant sporomorph species through the lower part of the Vicksburg Group. On the basis of these range and relative-frequency data for spores and pollen grains, the Jackson Group is divided into two zones. Zone I includes the upper part of the Claiborne Group and all but the uppermost part of the Jackson Group; zone II includes the uppermost part of the Yazoo Clay and extends into the overlying Vicksburg Group. The two zones and the boundary between them can be traced from western Mississippi to western Alabama. Sporomorph data support evidence from physical stratigraphy and from other fossils that only a minor disconformity is present between the Claiborne and Jackson Groups in this region. In western Mississippi, the zone I-zone II boundary is below the minor disconformity separating the open marine Yazoo Clay from the uppermost lagoonal part of that formation. Sporomorph data agree with faunal evidence that no unconformity is between the Jack son and Vicksburg Groups in eastern Mississippi. No sporomorph-bearing samples were available from the uppermost part of the Yazoo Clay at Little Stave Creek in western Alabama; however, samples from above and below the uppermost part of the Yazoo show that the zone I-zone II boundary either coincides with, or is slightly below, the unconformity separating the Jackson and Vicksburg Groups there. The information on sporomorph ranges and relative frequencies suggests that the flora and the vegetation of southeastern North America changed little from late middle Eocene time until almost the end of the late Eocene. Then, perhaps because of a change in climate, some species disappeared from the regional f

Professional Paper↗

USGS2023

Assessing environmental change associated with early Eocene hyperthermals in the Atlantic Coastal Plain, USA

Eocene transient global warming events (hyperthermals) can provide insight into a future warmer world. While much research has focused on the Paleocene–Eocene Thermal Maximum (PETM), hyperthermals of a smaller magnitude can be used to characterize climatic responses over different magnitudes of forcing. This study identifies two events, namely the Eocene Thermal Maximum 2 (ETM2 and H2), in shallow marine sediments of the Eocene-aged Salisbury Embayment of Maryland, based on magnetostratigraphy, calcareous nannofossil, and dinocyst biostratigraphy, as well as the recognition of negative stable carbon isotope excursions (CIEs) in biogenic calcite. We assess local environmental change in the Salisbury Embayment, utilizing clay mineralogy, marine palynology, δ 18 O of biogenic calcite, and biomarker paleothermometry (TEX 86 ). Paleotemperature proxies show broad agreement between surface water and bottom water temperature changes. However, the timing of the warming does not correspond to the CIE of the ETM2 as expected from other records, and the highest values are observed during H2, suggesting factors in addition to p CO 2 forcing have influenced temperature changes in the region. The ETM2 interval exhibits a shift in clay mineralogy from smectite-dominated facies to illite-rich facies, suggesting hydroclimatic changes but with a rather dampened weathering response relative to that of the PETM in the same region. Organic walled dinoflagellate cyst assemblages show large fluctuations throughout the studied section, none of which seem systematically related to CIE warming. These observations are contrary to the typical tight correspondence between climate change and assemblages across the PETM, regionally and globally, and ETM2 in the Arctic Ocean. The data do indicate very warm and (seasonally) stratified conditions, likely salinity-driven, across H2. The absence of evidence for strong perturbations in local hydrology and nutrient supply during ETM2 and H2, compared to the PETM, is consistent with the less extreme forcing and the warmer pre-event baseline, as well as the non-linear response in hydroclimates to greenhouse forcing.

Atlantic Coastal Plain↗

USGS1992

Late Pleistocene equilibrium-line reconstructions in the northern Peruvian Andes

ELA reconstructions using the toe-to-headwall-altitude ratio method for paleoglaciers in the Cordilleras Blanca and Oriental, northern Peruvian Andes indicate that ELAs during the last glacial maximum (LGM; marine isotope stage 2)) were c.4300 m in the Cordillera Blanca, c.3900-3600 m on the west side of the Cordillera Oriental, and c.3200 m on the east (Amazon Basin) side of the Cordillera Oriental. Comparison with estimated modern ELAs and glaciation thresholds indicate that ELA depression ranged from c.700 m in the Cordillera Blanca to c.1200 m on the east side of the Cordillera Oriental. Palynological evidence for drier conditions during the LGM in the tropical Andes suggests that ELA depression of this amount involved a temperature reduction (>5-6??C) that greatly exceeded the tropical sea-surface temperature depression estimates of CLIMAP (<2??C). The west to east increase in ELA depression during the LGM indicates that the steep modern precipitation gradients may have been even steeper during the LGM. -from Author

Boreas↗

USGS2003

U.S. Geological Survey resource assessment of selected Tertiary coal zones in Wyoming, Montana and North Dakota

In 1999, 1 Gt (1.1 billion st) of coal was produced in the United States. Of this total, 37% was produced in Wyoming, Montana and North Dakota. Coals of Tertiary age from these states typically have low ash contents. Most of these coals have sulfur contents that are in compliance with Clean Air Act standards and most have low concentrations of the trace elements that are of environmental concern. The U.S. Geological Survey (USGS) National Coal Resource Assessment for these states includes geologic, stratigraphic, palynologic and geochemical studies and resource calculations for major Tertiary coal zones in the Powder River, Williston, Greater Green River, Hanna and Carbon Basins. Calculated resources are 595 Gt (655 billion st). Results of the study are available in a USGS Professional Paper and a USGS Open-File Report, both in CD-ROM format.

Mining Engineering↗

USGS2011

A review of the lignite resources of Arkansas

This review of the lignite resources of Arkansas is a part of the U.S. Geological Survey's (USGS) National Coal Resource Assessment (NCRA) of the Gulf Coastal Plain Coal Province, which also includes coal-bearing areas in the states of Texas, Louisiana, Alabama, Mississippi, Tennessee, and Kentucky (see Ruppert et al., 2002 ; Dennen, 2009 ; and other chapters of this publication). Lignite mining is not planned in Arkansas in the immediate future, and the lignite resources of the state were not assessed in detail as part of the NCRA. This chapter includes reviews of the geology of the lignite-bearing units, historical mining, previous investigations of lignite resources, and coal quality. Palynological data for lignite samples collected in Arkansas as part of this work are presented in Table 1 .

Arkansas↗

USGS2011

A review of lignite resources of western Tennessee and the Jackson Purchase area, western Kentucky

This review of the lignite deposits of western Tennessee and the Jackson Purchase area in western Kentucky (Figure 1) is an updated report on part of the U.S. Geological Survey's National Coal Resource Assessment of the Gulf Coastal Plain Coal Province (see Ruppert et al., 2002; Hackley et al., 2006; Dennen, 2009; and other chapters of this publication). Lignite deposits of western Kentucky and Tennessee are an extension of the Gulf Coastal Plain Coal Province (Cushing et al., 1964), and currently are not economic to mine. These deposits have not been extensively investigated or developed as an energy resource. This review includes a description of the geology of the lignite-bearing units, a discussion of the available coal quality data, and information on organic petrology. Palynological data for lignite samples collected in Kentucky and Tennessee as part of this work are presented in Table 1. Lignite trace element data originally presented in Hackley et al. (2006) are not included in this report due to potential laboratory quality control issues during the time the samples were analyzed (U.S. Geological Survey Energy Resources Program, 2010).

Kentucky, Tennessee↗

USGS1982

The occurrence of the Complexiopollis-Atlantopollis zone (Palynomorphs) in the Eagle Ford Group (Upper Cretaceous) of Texas

The Lower and lower Upper Cretaceous palynological zones defined in the Atlantic Coastal Plain Province and which occur in the eastern Gulf Coastal Plain Province are characterized by a paucity of marine invertebrate fossils. As a result, correlation of these zones with European and provincial stages, as well as with other microfossil and megafossil zones is tenuous. However, an examination of a complete section of the Eagle Ford Group and adjacent strata in Texas reveals that: 1) the upper part of the Woodbine Formation and the Tarrant Formation of the overlying Eagle Ford Group represent a biostratigraphic interval that is absent in the Atlantic and eastern Gulf Coastal Plain Provinces; 2) the Complexiopollis-Atlantopollis Zone (zone IV of some authors) occurs within the Britton Formation (Eagle Ford Group), and is equivalent to the upper part of the Rotalipora cushmani-greenhornensis Subzone (planktic foraminifers) and possibly to the Sciponoceras gracile Zone (ammonites); 3) the Arcadia Park Formation (Eagle Ford Group) contains a mixed assemblage of palynomorphs that includes guides to both the Complexiopollis-Atlantopollis and the overlying Complexiopollis exigua-Santalacites minor Zones, suggesting that biostratigraphic equivalents of the Arcadia Park Formation are not represented in the Atlantic and eastern Gulf Coastal Plain Provinces; and 4) in the basal part of the Austin Chalk of Texas, only one guide palynomorph to the Complexiopollis-Atlantopollis Zone was recognized, but guides to the Complexiopollis exigua-Santalacites minor Zone are present. The Tuscaloosa Group of the eastern Gulf Coastal Plain appears to be biostratigraphically equivalent to the Complexiopollis-Atlantopollis Zone, and therefore correlative with the middle to upper part of the Britton Formation of the Eagle Ford Group.

Texas↗