bluuebunny/crossref_metadata_2025_split huggingface dataset:
The right way and the wrong way of presenting statistical and geological evidence in a court of law (a little knowledge is a dangerous thing!)
Authors: Isphording Wayne C. 
Published: April 2008

Abstract
On 21 March 1981 a young black male was abducted in Mobile, Alabama, and taken to a site across Mobile Bay where he was beaten and murdered. The act was in apparent revenge for the mis-trial of a black man accused of killing a white police officer from Birmingham, Alabama. Three members of the notorious Ku Klux Klan were apprehended and charged with murder. All were found guilty and the ringleader was executed in 1997; the others are now serving life sentences.
Ironically, the perpetrators were successful in having evidence tying them to the crime scene completely discredited. Statistical evidence purporting to show similarities in soil chemistry from samples taken from the victim, the defendants, and the crime scene was totally invalidated because improper statistical analyses were used. Following completion of the trial, the defence’s expert witness was contacted by the district attorney and asked to describe the appropriate statistical tests that should have been offered and that would have supported his case. He was further able to take solace by learning that strong mineralogical evidence could also have been used. It simply had not been reviewed by anyone who possessed the proper expertise.
Using geological information to identify apparent ‘misrepresentation’ of facts in a litigious situation
Authors: Isphording Wayne C. 
Published: April 2008

Abstract
On 7 November 1980, a motorcyclist entered a curve in a fog-shrouded, marshy area. The cyclist subsequently stated that his helmet visor suddenly ‘fogged up’, and that he was unable to raise the visor. The motorcycle slid out of control, throwing the rider into the path of an oncoming car; the impact led to the surgical removal of his left leg. The victim sued the local motorcycle dealer and the motorcycle visor manufacturer, alleging that he had not been advised that the visor could not be raised.
A number of lines of evidence argued against the plaintiff’s version of the events. Index of refraction, X-ray diffraction and fluorescence analyses clearly showed that the visor on the plaintiff’s helmet was not of the same material as visors sold by the defendants. Furthermore, although the plaintiff claimed he had purchased the visor the night before the accident, the visor had a curvature that could have been acquired only from being attached to the helmet for a number of weeks. Scanning electron microscopy (SEM) disclosed scratches that were found to contain orthoclase feldspar. The accident site, however, was on the Plio-Pleistocene Citronelle Formation, which is completely devoid of feldspar. Each of these points was used to show that the visor had not been purchased the night before the accident. The outcome of the trial, however, showed that nothing is certain in a court of law.
The nature of, and approaches to, teaching forensic geoscience on forensic science and earth science courses
Authors: Lee C. W. 
Published: April 2008

Abstract
Whereas geoscience depends in part on the classical nomological method of the environmental sciences, it is also distinguished by a discrete set of logical procedures that lend themselves to forensic analysis. It has been argued that, as geology is a derivative science, it only partially lives up to the classical model of scientific reasoning. It does, however, provide a model of scientific reasoning based on interpretive techniques and its historical nature. Reasoning in geoscience offers a method that is applicable to the uncertainties and complexities of real-life situations because we are seldom in possession of all the data that we would like in order to make an unbiased or objective decision. The ‘geological’ method, in which we fill the gaps in our knowledge with interpretation and reasonable assumptions, is exemplified by the pragmatism of geological and geomorphological analysis and is herein considered analogous to that undertaken by forensic practitioners. A problem-based learning situation based on a past geological/forensic case study is included to illustrate the approach advocated.
A review of natural CO
2
accumulations in Europe as analogues for geological sequestration
Authors: Pearce J. , Czernichowski-Lauriol I. , Lombardi S. , Brune S. , Nador A. , Baker J. , Pauwels H. , Hatziyannis G. , Beaubien S. , Faber E. 
Published: April 2008

Abstract

Natural geological accumulations of carbon dioxide occur widely throughout Europe, often close to population centres. Some of these CO
2
deposits leak, whereas others are sealed. Understanding these deposits is critical for selecting and designing underground storage sites for anthropogenic CO
2
. To provide confidence that the potential risks of geological CO
2
storage are understood, geologists are required to predict how CO
2
may behave once stored underground. Natural CO
2
accumulations provide a unique opportunity to study long-term geochemical and geomechanical processes that may occur following geological storage of anthropogenic CO
2
. In addition, natural CO
2
springs and gas vents can provide information on the mechanisms of gas migration and the potential effects of CO
2
leakage to the surface. This paper provides a description of some natural, European CO
2
occurrences.

CO
2
accumulations occur in many basins across Europe. In addition, volcanic areas and seismically active areas allow CO
2
-rich fluids to migrate to the near surface. Many of these occur in areas that have been populated for hundreds and thousands of years.

Stratigraphic traps have allowed CO
2
to accumulate below evaporite, limestone and mudstone caprocks. Comparisons between reservoir sandstone and equivalent nearby sandstones that contain no CO
2
indicate that reservoir sandstones may experience increased secondary porosity development through feldspar dissolution. Where fracture reactivation allows CO
2
-rich fluids to migrate, limited self-sealing may take place through calcite precipitation. Gas migration experiments indicate that, due to geochemical interactions, fine-grained seals would be able to trap smaller volumes of CO
2
compared to, for example CH
4
. In natural systems most leakage from depth occurs along fractures and is typically extremely localized on a metre-scale.
The role of hydrogeological and geochemical trapping in sedimentary basins for secure geological storage of carbon dioxide
Authors: Gunter William D. , Bachu Stefan , Benson Sally 
Published: April 2008

Abstract

Sedimentary basins throughout the world are thick piles of lithified sediments that, in many cases, are the hosts for fossil fuel resources. They may become even more important in the future if they are used for the storage of anthropogenic carbon dioxide. The efficiency of CO
2
geological storage is determined by the structure of the sedimentary basins, which have an intricate plumbing system defined by the location of high and low permeability strata that control the flow of fluids throughout the basin and define ‘hydrogeological’ traps. The most secure type of hydrogeological trapping is found in ‘stratigraphic’ and ‘structural’ traps in oil and gas reservoirs that have held oil and gas for millions of years. Another form of hydrogeological trapping is ‘hydrodynamic’ trapping which has been recognized in saline aquifers of sedimentary basins that have extremely slow flow rates. A volume of carbon dioxide injected into a deep hydrodynamic trap may take millions of years to travel by buoyancy forces updip to reach the surface before it leaks back into the atmosphere. Moreover, as the carbon dioxide migrates towards the surface, it dissolves in the surrounding brine (‘solubility’ trapping) and may react geochemically with rock minerals to become permanently trapped in the sedimentary basin by ‘ionic’ or ‘mineral’ trapping. The efficiency of the CO
2
geological storage in sedimentary basins depends on many factors, among the most important being CO
2
buoyancy, formation water density, lithological heterogeneity and mineralogy. A risk analysis must be completed for each site chosen for the geological storage of CO
2
to evaluate the trapping security.
Seismic monitoring at the Sleipner underground CO
2
storage site (North Sea)
Authors: Arts Rob , Eiken Ola , Chadwick Andy , Zweigel Peter , van der Meer Bert , Kirby Gary 
Published: April 2008

Abstract

The growing emissions of greenhouse gases, especially CO
2
, are seen worldwide as one of the major causes of climate change. International treaties like the Kyoto Protocol are supposed to contribute to reducing the emission of greenhouse gases. Underground sequestration has the potential to play an important role in keeping large volumes of CO
2
from escaping into the atmosphere in the short term. The first case of industrial scale CO
2
storage in the world (close to one million tonnes per year since 1996) is taking place at the Sleipner underground CO
2
storage site in the North Sea offshore Norway. Careful monitoring of the behaviour of the storage facility is required to establish its safety. To this end, two time-lapse seismic surveys have been acquired; the first repeat survey was completed in October 1999 and the second in October 2001. The presence of CO
2
beneath thin intra-shale layers within the reservoir has caused significant changes both in reflection amplitudes (up to a factor 10) and in travel time (more than 40ms) through the CO
2
plume (the velocity push-down effect). Some aspects of the interpretation of these time-lapse seismic surveys will be presented here.
The Neogene to Recent Rallier-du-Baty nested ring complex, Kerguelen Archipelago (TAAF, Indian Ocean): stratigraphy revisited, implications for cauldron subsidence mechanisms
Authors: Bonin B. , Ethien R. , Gerbe M. C. , Cottin J. Y. , Féraud G. , Gagnevin D. , Giret A. , Michon G. , Moine B. 
Published: April 2008

Abstract
The Kerguelen Archipelago is made up of a stack of thick piles of Tertiary flood basalts intruded by transitional to alkaline igneous centres at various times since 30 Ma ago. In the SW, the Rallier-du-Baty Peninsula is mostly occupied by two silicic ring complexes, each with an average diameter of 15 km, comprising dissected calderas cross-cut by subvolcanic cupolas. Previous radiometric determinations yield ages ranging from 15.4 to 7.4 Ma in the southern centre, and 6.2 to 4.9 Ma in the northern one. The felsic ring dykes were injected by coeval mafic magmas, forming, successively, swarms of early mafic enclaves, disrupted synplutonic cone sheets, and late cone-sheets. After the emplacement and subsequent unroofing of the plutonic ring complexes, abundant and thick trachytic pyroclastic flows and falls were emitted from the younger caldera volcanoes, while hawaiite and mugearite lava flows were erupted from marginal maars and cones. Huge trachyte ignimbritic flows filled the glacial valleys in the central Peninsula, and capped lacustrine deposits and older lava flows, while related pumice falls are widespread throughout the archipelago. This powerful plinian eruption took place after the network of glacial valleys was established, but before the Little Ice Age that occurred during the last centuries. In the south of the peninsula, even younger trachytic formations are exposed, and fumarolic vents are still active.

The growth mechanisms of a caldera-related ring complex can be explained as a repetitive sequence of two eruptive episodes. The first episode of hydrofracturing, induced by volatile exsolution within the evolving magma chamber, creates a vertical circular fracture zone, along which highly vesiculated magmas are emitted during explosive eruptive events occurring at the surface in a caldera volcano. It is followed by a second episode of cauldron-subsidence of a crustal block down to the degassed magma chamber, induced by pressure release. Downward movement of the crustal block favours the emplacement at shallow depths within the older caldera-filling formations, of discrete magmatic sheets characterized by a 16-km mean diameter and a 1-km mean thickness, corresponding to an average unit volume of 200 km
3
. Actually, the estimated volumes of the different igneous episodes within the Rallier-du-Baty nested ring complex vary from 60 to 900 km
3
, and correspond to the production during 15 Ma of about 2800 ± 850 km
3
of new materials and a net crustal growth of about 100 ± 30 × 10
3
m
3
per year.
Tectonic control on laccolith emplacement in the northern Apennines fold-thrust belt: the Gavorrano intrusion (southern Tuscany, Italy)
Authors: Mazzarini Francesco , Corti Giacomo , Musumeci Giovanni , Innocenti Fabrizio 
Published: April 2008

Abstract

Mechanical discontinuities within the crust, represented by tectonic structures (faults) or lithological heterogeneities, strongly control the emplacement of magmas as tabular intrusions within the middle-upper crust. The occurrence of mechanical layering is a common feature in fold and thrust belts. In the northern Apenniness, a Cenozoic fold-thrust belt affected in its inner part by Neogene magmatism, the Gavorrano laccolith (southern Tuscany) is a particularly suitable example for studying the relationships between magmatism and tectonic structures. New geological mapping, together with a large amount of subsurface data available from historical mining activity in the area, have allowed the reconstruction of:

1
the original relationships of the intrusion within the nappe pile, and

2
the laccolithic shape of the intrusion.

Using the Gavorrano laccolith as an example, we propose that the emplacement of Neogene intrusions in southern Tuscany was strongly controlled by the occurrence of mechanical discontinuities represented by thrust zones in the nappe pile.
Rate of construction of the Black Mesa bysmalith, Henry Mountains, Utah
Authors: Habert Guillaume , De Saint-Blanquat Michel 
Published: April 2008

Abstract

At shallow-crustal levels, the most efficient process for the accommodation of magma emplacement is roof lifting, which induces an upward vertical displacement of the Earth’s surface. Estimates of the rate and duration of this process have rarely been published. One of the most spectacular places where plutons constructed by such mechanisms are exposed is the Henry Mountains in Utah. In this place, Pollard & Johnson (1973) derive a time of ‘less than several weeks’ for the construction of the Black Mesa bysmalith (BMb), by coupling a mechanical approach with a model for the flow rate of Bingham magma in a tabular conduit with a constant driving pressure at the feeder. The aim of this new study of the BMb is to evaluate the maximum duration of its emplacement and propose a feasible scenario for its construction. Our study of the pluton’s internal structures suggest that the BMb is a multi-pulse pluton. We have constrained the duration of BMb emplacement by simulating the thermal evolution of the growing pluton and its wallrocks for different construction scenarios. We have adjusted the number, the thickness and the frequency of the pulses with our textural ‘time’ constraints, which are the absence of solid-state textures around internal contacts, which implies that a melted zone was maintained in the intrusion during its construction; and the absence of significant contact metamorphism or recrystallization which means that the increase of temperature in the host rock was relatively small, or short-lived, or both. In accordance with the previous estimates of Pollard & Johnson (1973), we propose that the emplacement of the BMb was a very short geological event, with a
maximum
duration in the order of 60 years, implying
minimum
vertical displacement rates of the wallrocks above the pluton of 4 metres per year. Moreover, our simulations indicate that pulses around 20 metres thick rapidly injected approximately every three months are the most consistent with the constraints from field observations.
Rise and fall of a nested Christmas-tree laccolith complex, Elba Island, Italy
Authors: Westerman D. S. , Dini A. , Innocenti F. , Rocchi S. 
Published: April 2008

Abstract
In two separate areas of western and central Elba Island (Italy), Late Miocene granite porphyries are found as shallow-level intrusions inside a stack of nappes rich in physical discontinuities. Detailed mapping of intrusive rocks, along with their relations with country rocks, show that outcrops from western and central Elba Island expose the same rock types, with matching intrusive sequence, petrography and geochemical features. Structural and geological data indicate that these layers were originally part of a single sequence that was split by eastward-directed décollement and tilting. The two juxtaposed portions of the original sequence allow the restoration of a 5-km thick sequence, made up of nine main intrusive layers, building three Christmas-tree laccoliths nested into each other to support a structural dome. During their construction, the role of the neutral buoyancy level was of minor significance with respect to the role played by the relatively thin overburden and/or the large availability of magma traps inside the intruded crustal section. Emplacement of the Monte Capanne pluton into the base of the domal structure likely caused oversteepening and initiated decapitation of the complex, with gravity sliding of the upper half off the top.
Hydrothermal vent complexes associated with sill intrusions in sedimentary basins
Authors: Jamtveit Bjørn , Svensen Henrik , Podladchikov Yuri Y. , Planke Sverre 
Published: April 2008

Abstract

Subvolcanic intrusions in sedimentary basins cause strong thermal perturbations and frequently cause extensive hydrothermal activity. Hydrothermal vent complexes emanating from the tips of transgressive sills are observed in seismic profiles from the Northeast Atlantic margin, and geometrically similar complexes occur in the Stormberg Group within the Late Carboniferous-Middle Jurassic Karoo Basin in South Africa. Distinct features include inward-dipping sedimentary strata surrounding a central vent complex, comprising multiple sandstone dykes, pipes, and hydrothermal breccias. Theoretical arguments reveal that the extent of fluid-pressure build-up depends largely on a single dimensionless number (

Ve

) that reflects the relative rates of heat and fluid transport. For

Ve

>> 1, ‘explosive’ release of fluids from the area near the upper sill surface triggers hydrothermal venting shortly after sill emplacement. In the Karoo Basin, the formation of shallow (< 1 km) sandstone-hosted vents was initially associated with extensive brecciation, followed by emplacement of sandstone dykes and pipes in the central parts of the vent complexes. High fluid fluxes towards the surface were sustained by boiling of aqueous fluids near the sill. Both the sill bodies and the hydrothermal vent complexes represent major perturbations of the permeability structure of the sedimentary basin, and are likely to have long time-scale effects on its hydrogeological evolution.
Irish Lower Carboniferous replacement dolomite: isotopic modelling evidence for a diagenetic origin involving low-temperature modified seawater
Authors: Wright Wayne R. , Somerville I. D. , Gregg J. M. , Shelton K. L. , Johnson A. W. 
Published: April 2008

Abstract

Irish Lower Carboniferous (Dinantian Subsystem) carbonate rocks are extensively replaced by planar dolomite. This dolomitization is unrestricted in lithology replaced, age of host rock and geographical occurrence. This paper presents geochemical (δ
18
O, δ
13
C,
87
Sr/
86
Sr, Sr conc.) modelling evidence, and discussion supporting and extending the theory that replacement planar dolomitization formed in the Waulsortian, and other host rocks under shallow burial conditions via interaction with a low-temperature (
c.
50–70 °C) slightly modified seawater. The probable mechanism for transporting the fluid into the carbonates appears to be a variant of Kohout convection, driven by an elevated geothermal gradient. As seawater was drawn inwards, it encountered the units beneath the Waulsortian and scavenged radiogenic Sr. This warmer fluid then migrated upwards and up-slope into overlying Waulsortian and Supra-Waulsortian platform carbonates still undergoing early diagenesis. Calcium in pore fluids, provided by dissolution-precipitation reactions of calcite, was probably incorporated into the modified, and slightly warmer, seawater resulting in the variability noted in the planar replacement dolomite Sr concentrations. The early low-temperature dolomitization of the carbonate host rocks provided a crucial preparation event by creating/redistributing and preserving porosity and permeability. Younger regionally migrating high-temperature fluids directly related to the Zn-Pb mineralization in Ireland exploited these dolomitzed units as aquifers. The models and methodologies presented for understanding dolomite genesis in the Lower Carboniferous rocks of Ireland can be applied to any dolomitized reservoir.
Origin and petrophysics of dolostone pore space
Authors: Lucia F. Jerry 
Published: April 2008

Abstract
The common claim that dolomitization creates 12% porosity is based on the mole-for-mole replacement equation. However, in the past 50 years, data have been collected demonstrating that dolomitization does not create porosity. Instead, dolostones inherit the porosity and fabric of the precursor limestone, and porosity is reduced by overdolomitization. The porosity of the precursor limestone depends on the diagenetic history up to the time of dolomitization. Data show that: (1) carbonates are born with high porosity and lose porosity gradually over a long period; and (2) mud-dominated fabrics compact more readily than grain-dominated fabrics. The problem of estimating the time of dolomitization is minimized by confining observations to young limestones and associated dolostones. Limited data from Holocene dolomitic sediments suggest no change in porosity with dolomitization. Study of Plio-Pleistocene carbonates in Bonaire, Netherlands Antilles, demonstrates that precursor limestones are more porous than dolostones. Limestones average 25% porosity, whereas dolostones average 11% porosity. Data from the Neogene of the Great Bahama Bank show that dolostones and adjacent limestones both have 40% porosity. Porosity studies of the Jurassic Arab D Formation show that dolostones and associated grain-dominated limestones have similar porosity ranges and that the decrease in porosity with increasing dolomitization results from compaction of the mud-dominated fabrics. These data suggest that porosity in dolostone is not created by a mole-for-mole replacement mechanism. Instead, dolostone porosity is: (1) inherited from the precursor limestone; and (2) occluded by the process of overdolomitization. Palaeozoic dolostones, however, are commonly more porous than juxtaposed limestones. The explanation for this observation is that limestones lose porosity through compaction and cementation, whereas dolostones resist compaction and retain much of their porosity.
Permeability studies have demonstrated that dolomitization of grain-dominated limestones usually does not change porosity-permeability relationships. Instead, precursor limestone fabric controls pore-size distribution. The dolomite crystal size of a muddominated dolostone may, however, be larger than the carbonate mud size, improving the porosity-permeability relationship substantially. Hence, there is a predictable relationship between interparticle (grains or crystals) porosity, permeability, precursor grain size and dolomite crystal size.