bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sedimentary Serpentinite of the Miocene Big Blue Formation Near
Cantua Creek
Authors: Casey Tom Ann L. , Dickinson William R. 
Published: April 2015

Abstract
Between Anticline Ridge on the south and the Ciervo Hills on the north, serpentinous strata of the Big Blue Formation lie strati graphically between Middle Miocene Temblor Formation and Upper Miocene Santa Margarita Formation in homoclinal exposures of Tertiary strata that flank the western margin of the Great Valley. Mapping of three distinctive lithologic units within the Big Blue Formation near Cantua Creek defines key aspects of its unusual origin (see Fig. 30). Foliate but unstratified serpentinite breccia, thickest on the outcrop between Salt and Martinez Creeks, forms the body of a protrusive serpentinite extrusion that flowed as a sheared mass across an unconsolidated substratum of Temblor sand, which was partly scraped away beneath the mass-flow and was locally plowed into chaotically rumpled folds that piled up at the advancing margin of the protrusive mass. Bedded serpentinite-clast conglomerates and breccias, with intercalated serpentine-grain sandstones and associated serpentinous debris-flow deposits, were formed by fluvial reworking of the protrusive serpentinite. Detrital serpentinite locally underlies but more commonly overlies and most typically flanks the latter as a facies equivalent. Interbedded serpentine-grain sandstones and serpentinous claystones of probable marine origin exposed laterally along strike apparently formed as an extensive facies fringe of serpentinite detritus dispersed widely from a central core of protrusive and coarser detrital serpentinite. Santa Margarita beds rest conformably on the finer detrital serpentinite but uncon-formably on protrusive serpentinite and associated deposits. Easterly paleocurrents from clast imbrications in detrital serpentinite suggest that the serpentinite source lay west of the present outcrop belt. Dispersal of serpentinite debris perhaps was fed by protrusive diapiric movement of Mesozoic serpentinite mobilized in the core of an ancestral Joaquin Ridge anticline, whose initial growth thus may have coincided with the Miocene onset of rapid motion along the late Cenzoic San Andreas fault system.
Descriptions of Field Trip Stops 4, 5, and 6
Authors: Casey Tom Ann L. , Dickinson William R. 
Published: April 2015

Abstract
Bedded serpentinite-clast conglomerate and sedimentary breccia with subordinate debris flow deposits form most of the Big Blue Formation between Salt and Cantua Creeks (see Fig. 32). Rusty brown outcrops in resistant ledges are characteristic (Fig. 39). A total thickness of 50 to 100 m is estimated. The bedded serpentinite-clast rudites, in general, lap depositionally upon the flank of the thick lens of protrusive serpentinite. About 15 m of foliate serpentinite breccia persists locally beneath bedded serpentinite-clast conglomerate and breccia as far north as the Lillis Ranch (Fig. 40).
The bedded rudites consist of subangular to sub-rounded serpentinite-clast gravel associated with interstitial and interstratified serpentine-grain sand and cemented by carbonate (Fig. 41). The largest clasts are about 1 m in diameter, but most are much smaller. The texture of the sandy matrix is plainly fragmental (Fig. 42), and there is no hint of a shear fabric. Lenticular bedding and channel structures characteristic of braided-stream deposits are prominent (Figs. 43-45). Nearly all clasts are serpentinite, although rare fragments, of other rock types occur in some beds, and the chrome garnet, uvarovite, is common in the sand fraction.
The proportion of serpentinite-clast conglomerate and sedimentary breccia declines and the proportion of serpentine-grain sandstone increases with distance laterally away from the sequence of foliate serpentinite breccia. In the canyon of Cantua Creek (see Fig. 33), more than half the unit is composed of serpentine-grain sandstone that is intercalated between more prominent layers of coarser serpentinite detritus.
Crudely stratified serpentinite-clast rudites that represent debris-flow deposits locally occur strati graphically between foliate breccia and bedded conglomerate and breccia.
General Geology of the Northern Coast Ranges and the Wilbur
Springs Area
Authors: Carlson Christine 
Published: April 2015

Abstract
The Northern Coast Ranges (Fig. 61) are a composite geomorphic province consisting of structurally controlled, northwest trending, enechelon ridges and valleys that extend from the Klamath Mountains in the north to San Francisco Bay in the south. The core of the Coast Ranges consists of complexly deformed Upper Jurassic to Early Tertiary rocks of the Franciscan Complex. This core is structurally overlain to the east by less deformed, late Mesozoic marine, clastic rocks of the Great Valley Sequence. These two essentially coeval terranes are juxtaposed along a major low-angle fault, the Coast Range Thrust (Bailey et al., 1964), whose present geometry is extensively modified by Tertiary deformation of the Coast Ranges and extensive strike slip displacement along reactivated Mesozoic structural discontinuities (McLaughlin, 1974, 1981; Suppe and Foland, 1978; Suppe, 1979).
The Franciscan Complex is a highly deformed, lithologically heterogeneous assemblage. It consists predominately of graywacke and metagraywacke with subordinate shale, altered mafic volcanic rocks, radiolarian chert and minor limestones, which range from unmetamorphosed through zeolite, prehnite-pumpellyite, greenschist, and blueschist facies. It also includes minor blueschist and eclogite facies exotic blocks. The distribution and relationships of these rocks is complicated by numerous thrusts and chaotic melange zones. Vestiges of original stratigraphic relations are only locally preserved in large tectonic slabs and thrust sheets. Thrust sequences “top” eastward and “young” to the west and the regional tectonic fabric dips eastward at high angles. Overall, the high P, low T metamorphic grade increases west to east but the metamorphic facies progression is more complicated in detail.
Depositional Environments and Sedimentary Facies of Foliate
Serpentinite Breccias, Wilbur Springs
Authors: Carlson Christine 
Published: April 2015

Abstract
Voluminous serpentinite strata interfinger with Lower Cretaceous terrigenous clastics of the Great Valley sequence along the western edge of the Sacramento Valley. These deposits are exposed in the core of a regional, southeast-plunging structure, the Wilbur Springs anticline. The sedimentary serpenti-nites form a distinctive lithologic unit of foliate serpentinite breccias in road cuts along Highway 20 just west of its intersection with Highway 16.
Extensive serpentinite masses of sedimentary origin were first reported in the area of Wilbur Springs by Taliaferro (1943). He recognized their association with fault-bounded serpentinite of the ophiolite belt but was unable to establish sufficient criteria to distinguish between the two types in many cases. Thus the origin of much of the exposed serpentinite remained unresolved. Lawton (1956), citing numerous fossil discoveries within serpentinite breccia and gradational contacts with surrounding Great Valley strata, suggested that all of the serpentinite bodies south of Wilbur Springs were the products of sedimentary processes. Although he noted textural variation between chaotic and stratified units, he did not attach genetic significance to these facies changes. He considered all the deposits detrital accumulations despite the poor stratification, chaotic nature, schistose fabric, and the admitted lack of internal clastic textures in many of the bodies. The foliation was attributed to later tectonism, which he thought had obliterated original depositional features.
Moiseyev (1966), in his study of the mercury mineralization of the Wilbur Springs District, concurred with Lawton's findings and provided further documentation of the detrital nature of some of the ultramafic rocks. Stressing the inherent difficulty in discriminating sedimentary serpentinites, he concluded that lateral gradation of foliate breccia into coarse elastics of ultramafic composition and the presence of fossils in the serpentinite are the only unambiguous criteria of sedimentary origin (Moiseyev, 1970).
Upper Precambrian-Lower Paleozoic Clastic Sequences, Blue Ridge and Adjacent Areas, Virginia and North Carolina
Authors: Schwab Frederic L. 
Published: April 2015

Abstract
Late Proterozoic to Early Paleozoic stratified assemblages of the central and southern Appalachian Blue Ridge, Piedmont, and Valley and Ridge provinces document the initial origin and early evolution of the eastern margin of ancient North America. A series of thick, late Proterozoic (post-Grenville, 950 to 1100 Ma) clastic sequences record an initial episode of continental distension and rifting with the development of localized, interior, Triassic-like grabens adjacent to a major, scarp-bounded continental edge that bordered either a Proto-Atlantic (Iapetus) Ocean or a smaller, marginal back-arc basin. Overlying, younger stratified sequences document the gradual development of a passive, Atlantic-type continental margin with shallow water shelf sediments of a continental terrace deposited subjacent to deeper water continental rise deposits.
The purpose of this field excursion is to familiarize participants with the regional setting, overall lithology and characteristics, and tectonic setting of selected units within the Blue Ridge and adjacent regions that document the evolutionary history briefly described above. All stops will be within the Blue Ridge province itself or along its immediate boundaries with the Piedmont and Valley and Ridge provinces. Stratigraphic units to be seen include: (1) Grandfather Mountain Formation: late Proterozoic fanglomerate and associated alluvium of a rift-related, Newark-like interior basin; (2) Mount Rogers Formation (or Volcanic Group): glacio-fluvial deposits (including tillite and dropstone-bearing laminated pebbly mudstone) and interbedded peralkaline pyroclastics and flows; (3) earliest Cambrian Chilhowee Group: initial shallow water shelf deposits of a developing passive, Atlantic-type continental margin terrace; and (4) Early Paleozoic Alligator Back Formation: metasedimentary and meta-volcanic rocks believed to be altered from deeper water continental rise deposits believed to have been deposited subjacent to the developing continental shelf.
Volcaniclastic Rocks of the Carolina Slate Belt, Central North Carolina
Authors: Butler James Robert 
Published: April 2015

Abstract
The Carolina slate belt includes volcanic and sedimentary rocks of Late Precambrian and Cambrian age, metamorphosed to lower greenschist facies, that extend through the Piedmont from Georgia to Virginia. The segment in central North Carolina (Fig. 1) is probably the best-known part of the belt. Rocks in the Albemarle area are mildly deformed and metamorphosed; the dominant structures are open folds plunging southwest and the regional metamorphism is chlorite and biotite grade. The Albemarle region includes type localities for several stratigraphic units. The localities described here are on the Albemarle (Conley, 1962) and Denton (Stromquist, Choquette, and Sundelius, 1971) 15-minute quadrangles. The guidebook by Stromquist and Conley (1959) marked the beginning of modern studies in the central Carolina slate belt, as they demonstrated that stratigraphy and structure could be worked out on a regional basis. Conley and Bain (1965) applied formation names to the section in the Albemarle area (Fig. 2) and extended this stratigraphic nomenclature through most of the slate belt in North Carolina. In the Albemarle region, a thick, dominantly felsic volcanic unit (Uwharrie Formation) is overlain by a dominantly sedimentary sequence (Albemarle Group). The Morrow Mountain Rhyolite and Badin Greenstone of the Tater Top Group were interpreted to be the uppermost units and to lie with angular unconformity above folded older units (Conley and Bain, 1965). Stromquist and Sundelius (1969) reinterpreted part of the middle and upper stratigraphic sequence. They considered the Tater Tbp Group to be interlayered with other units of the Albemarle Group, rather than
Cretaceous-Paleocene Boundary, Lenoir County, North Carolina
Authors: Brown Philip M. , Miller James A. 
Published: April 2015

Abstract
In eastern Lenoir and western Craven Counties, located in the central part of the North Carolina Coastal Plain, a series of tilted and partially-exposed structural blocks define the limits, at the surface, of a zone of tectonic uplift and subsidence called the Graingers wrench zone (Brown and others, 1977). The segment of the wrench zone exposed at the surface is about 10 miles (16 km) long and 15 miles (24 km) wide. It trends NE-SW, plunges to the NE, is characterized by a sense of left-lateral displacement, and lies athwart the NW-SE trending Neuse River in the vicinity of Graingers, N.C.
The structural blocks characteristic of the wrench zone comprise a mosaic of juxtaposed grabens, half grabens, and horsts. In part, the blocks are composed of Navarroan, Midwayan and Claibornian sediments. The general boundaries of the blocks and their positions relative to each other, are established chiefly from the observed lateral discontinuity and variance in the relative vertical position of essentially flat-lying indurated mudstones (volcaniclastics) of Midway age, and from observed variance in elevation, relative to sea level, of the unconformity between Midwayan and Navarroan sediments.
The purpose of the field trip is to provide the participants with the opportunity to examine and collect from the Cretaceous-Tertiary boundary at five fresh exposures in the wrench zone, to collect from sections where the boundary is exposed, and to observe the manner in which rocks of different ages and and resistance (Midwayan porcelanites and Navarroan clayey sands) have reacted to the same
Deltaic Evolution During a Major Transgression
Authors: Eckard Timothy L. , Hayes Miles O. , Sexton Walter J. 
Published: April 2015

Abstract
The sedimentary deposits of the Santee River deltam, South Carolina, consist of two primary facies: (1) a 13-m-thick Late Pleistocene-Holocene alluvial sequence composed of coarse-grained, fluvial, point-bar deposits; overlain by (2) a 7-m-thick fine-grained deltaic complex. During the Wisconsin low stand of sea level, the river incised a deep valley, which in response to the Holocene sea-level rise, aggraded with fluvial deposits. During active channel migration within the confines of the valley walls, multistage, stacked, point-bar and channel sands were deposited. A decrease in river gradient brought about by the continued rise in sea level resulted in widespread overbank deposition and eventual stabilization of the fluvial channels by 7,000-5,000 BP. Sea-level stabilization at about this same time period initiated constructional phases of delta formation.
A stratigraphic model for delta evolution has been constructed through analysis of 63 vibracores, 45 power augers, 30 gouge augers, and 12 radiocarbon dates. The alluvial sediments comprising the valley fill unit are composed of pebbly, coarsegrained sand deposited as fluvial, multistage, stacked, point-bar and channel deposits capped by a widespread, fining- upward, sandy clay unit representing floodplain deposition. The overlying deltaic complex is a gently inclined, seaward–thickening sediment body consisting of a lower delta plain and delta front facies. The lower delta plain deposits are composed primarily of organic-rich muds deposited in freshwater swamp and open bay environments. In a seaward direction, these deposits interfinger with estuarine sands and muds deposited in back–barrier–related environments of the delta front. The present delta front is in a destructive phase as the shoreline is advancing landward beyond reworked, abandoned deltaic deposits in water depths of 5-10 m. The facies complex of the Santee River delta should provide some insight into the stratigraphic nature of medium-to small-sized deltas deposited in a mixed energy setting during a major transgression.
Upper Ordovician and Silurian Stratigraphy of the Virginia and West Virginia Valley and Ridge
Authors: Diecchio Richard J. 
Published: April 2015

Abstract
Two pronounced effects of the Taconic Orogeny were the creation of an eastern source area which influenced sedimentation through much of the Appalachian basin, and the early deformation of the eastern margin of the Appalachian basin. This field trip will investigate the stratigraphy of the Taconian (Upper Ordovician) and post-Taconian (Silurian) clastic strata in an attempt to illustrate the sedimentologic and structural effects of the Taconic Orogeny in the eastern portion of the Appalachian basin.
The Taconian clastic sequence is an orogenic progradational sequence. The distal (western) facies of the clastic sequence were deposited between the carbonate shelf and the source area, in a deep basin which was created by tectonic downwarping of the eastern edge of the carbonate bank. During deposition of the Taconian clastics, there occurred a pronounced, probably glacio-eustatic lowering of sea level, which lasted until the beginning of the Silurian.
The Silurian clastics are a series of post-orogenic quartz sandstones and mudrocks, the upper portion of which changes facies basinward to limestone. The sandstones comprise a number of tongues which are thickest near the basin margin, and thin to the west. The Silurian strata were deposited in relatively shallow water, implying that tectonic downwarping had ceased. The large-scale inter-tonguing of strata may have been caused by sea-level fluctuations.
Morphology and Stratigraphy of Mesotidal Shoreline Features
Authors: Hayes Miles O. , Sexton Walter J. , Imperato Douglas P. 
Published: April 2015

Abstract
This one-day field trip is designed to examine the morphology and stratigraphy of a mesotidal tidal inlet, Price Inlet, and barrier island, Capers Island, located in the central portion of the South Carolina coast. The tidal range in the study area averages around 2 m (mesotidal; Davies, 1964) and waves average 50-60 cm in height. Dominant longshore sediment transport is from north to south, with 150,000-200,000 m3 of sand moving past any given point on the Capers Island beach each year (Kana, 1976, 1979).
The field trip will be conducted at low tide, which will allow the participants to observe in detail intertidal features such as bedforms, swash bars, and inlet channels. Trenches dug through swash bars and beach berms will allow for detailed inspection of the internal sedimentary structures of these features. The main ebb channel of the inlet will be surveyed with a depth recorder and bottom samples will be collected along its length in order to demonstrate the effects of the tidal currents in shaping the inlet and its ebb-tidal delta. A 3 km walk along the front of the northern half of Capers Island, as well as a perpendicular transect across the island’s midsection, will expose the participants to all important aspects of the morphology of a typical regressive, mesotidal barrier island. A core taken in the middle of the island will be displayed in order to augment the description of the island’s Holocene stratigraphy.
An oblique aerial photograph of the area to be visited is
Cape Lookout Cuspate Foreland Depositional Systems
Authors: Moslow Thomas F. , Heron S. Duncan 
Published: April 2015

Abstract
The sedimentary record of 130 km of microtidal (0.9 m tidal range) high wave energy (1.5 m average wave height) barrier island shoreline of the Cape Lookout cuspate foreland has been evaluated through examination of 3136 m of subsurface samples from closely spaced drill holes. Holocene sedimentation and coastal evolution has been a function of five major depositional processes: (1) eustatic sea-level rise and barrier-shoreline transgression; (2) lateral tidal inlet migration and reworking of barrier island deposits; (3) shoreface sedimentation and local barrier progradation; (4) storm washover deposition with infilling of shallow lagoons; and (5) floodtidal delta sedimentation in back-barrier environments.
Twenty-five radiocarbon dates of subsurface peat and shell material from the Cape Lookout area are the basis for a late Holocene sea- level curve. From 9000 to 4000 B.P. eustatic sea level rose rapidly, resulting in landward migration of both barrier limbs of the cuspate foreland. A decline in the rate of sea-level rise since 4000 B.P. resulted in relative shoreline stabilization and deposition of contrasting coastal sedimentary sequences. The higher energy, northeast barrier li.h (Core and Portsmouth Banks) has migrated landward producing a transgressive sequence of coarse-grained, horizontally bedded washover sands overlying burrowed to laminated backbarrier and lagoonal silty sands. Locally, ephemeral tidal inlets have reworked the transgressive barrier sequence depositing fining-upward spit platform and channel-fill sequences of cross-bedded, pebble gravel to fine sand and shell. Shoreface sedimentation along a portion of the lower energy, northwest barrier limb (Bogue Banks) has resulted in shoreline progradation and deposition of a coarsening-up sequence of burrowed to cross-bedded and laminated, fine-grained shoreface and foreshore sands. In contrast, the adjacent barrier island (Shackleford Banks) consists almost totally of inlet-fill sediments deposited by lateral tidal inlet migration. Holocene sediments in the shallow lagoons behind the barriers are 5-8 m thick fining-up sequences of interbedded burrowed, rooted and laminated flood- tidal delta, salt marsh, and washover sands, silts and clays.
While barrier island sequences are 10 m in thickness, inlet-fill sequences may be as much as 25 m thick and comprise an average of 35% of the Holocene sedimentary deposits. Tidal inlet-fill, back- barrier (including flood-tidal delta) and shoreface deposits are the most highly preservable facies in the wave-dominated barrier-shoreline setting. In the Cape Lookout cuspate foreland, these three facies account for over 80% of the sedimentary deposits preserved beneath the barriers. Foreshore, spit platform and overwash facies account for the remaining 20%.
Field Trip Introduction
Authors: Harris Paul M. (Mitch) , Simo J. A. (Toni) 
Published: April 2015

Abstract
The Guadalupe and Hueco Mountains are exquisite natural laboratories for studying the stratigraphy, depositional facies, and diagenetic overprint of Permian platform and reef carbonates. Well-studied outcrops from these two classic localities serve as important analogs for other areas where the data is more limited. In addition, studies from the two areas have had immediate application to subsurface hydrocarbon exploration and exploitation efforts in the immediately adjacent Permian Basin.
Our field trip of three days will emphasize the stratigraphic framework, facies, and diagenesis of a Lower Permian (Wolfcampian) low-relief carbonate platform outcropping in the Hueco Mountains and an Upper Permian (Guadalupian) steep-rimmed platform of the Guadalupe Mountains. We invite questions and discussion at all field stops, as our group has diverse backgrounds and interests and any discussion will be beneficial to all.
The focus of the trip in the Hueco Mountains is on the evolution of the shelf-margin architecture and fauna! change. The exposures allow us to view the architectural elements of a prograding and retrograding shelf margin in ice-house conditions as well as the biotic response to environmental change. A relevant part of the exposure to visit is the facies variability both temporally and laterally.
Our emphasis in the Guadalupe Mountains is on the Capitan margin, as well as the related shelf and basin deposits. Large-scale outcrops like that of McKittrick Canyon offer an unparalleled view into the inside of a progradational platform, and we hope you will agree that the hike up the Permian Reef Geology Trail presents an