96 research outputs found
User guide Total Organic Carbon (TOC) data
This report describes the Total Organic Carbon (TOC) point dataset. It contains a brief summary of the methodology and guidance on how the data can be used. The data has been critically assessed and its fitness for purpose determined by BGS Energy specialists.
The purpose of this user guide is to enable those licensing this dataset to have an appreciation of how the data set has been created and therefore better understand the potential applications and limitations that the dataset may have
User Guide Mining Hazard (not including coal). Version 7
This report describes the national scale Mining Hazard not including coal version 7 data. The
methods used to create the dataset have been evaluated and deemed fit for purpose by specialists
in BGS.
This User Guide describes the data outlines why it was created; its potential uses and provides
advice on using the dataset
Proposed methodology for the development of a mining geohazards data layer
This report describes the work carried out for the Mining Geohazard facet of the GeoHazarDs
project up to the 31st March 2003 when development work on the mining aspects of the project
were suspended. The work carried out so far has been restricted to England and Wales, once the
methodology has been verified the area covered will be extended to incorporate Scotland.
Work carried out so far has covered
• Simultaneous data capture of local knowledge and national data coverages as a
foundation for the project.
• Establishment of a GIS framework to hold all data produced and utilised by the
project.
• Explanations of the data structure from capture and manipulation of the Overview
ARUP data layer through to the inclusion of detailed local datasets e.g. the Bath stone
information.
• Proposed methodology using shafts, veins and formations rated on a series of factors
with worked examples illustrating strengths and weaknesses of the methods.
• Future modifications to the methodology developed so far, looking at spheres of
influence rather than raw or generalised themes
User guide for Vitrinite Reflectance data
This report describes the vitrinite reflectance point data. The method used to create the dataset has been critically assessed and its fitness for purpose determined by specialists at BGS
Geological indicators of flooding : user guidance notes
This report provides guidance notes for all users of the Geological Indicators of Flooding V5.2 dataset. It provides a description of the history, details of the data content and data format and notes on the recommended scale of use/search criteria
Mineral safeguarding areas for North York Moors National Park authority
This report describes work carried out by the British Geological Survey (BGS) on behalf of the
North York Moors National Park Authority to delineate draft Mineral Safeguarding Areas
(MSAs), the results of which will be used to undertake a mineral consultation safeguarding
exercise. The approach taken is in accordance with the methodology outlined in ‘Mineral
safeguarding in England: good practice advice’ (Wrighton et al., 2011). National policy for
minerals safeguarding, at the time of the study, is contained within the ‘National Planning Policy
Framework’ that was published in March 2012.
The work undertaken in this study involved the production of maps showing the extent of
mineral resources in the North York Moors National Park and the production of a recommended
safeguarding methodology for each mineral resource informed by consultation. This report will
be used to inform the establishment of MSAs through minerals planning policy, MSAs
themselves are not finalised until relevant planning policy is adopted. Data depicted on the maps
have been provided in digital format to the authority for use within a Geographical Information
System
Environmental and economic information for aggregates provision
This report describes a one-year research project entitled ‘Environmental and economic information
systems for aggregates provision’. This project is an extension to previous research on Strategic
Environmental Assessment (SEA) and future aggregates extraction, which was carried out by the British
Geological Survey (BGS) and reported in early 2004 (Steadman, et al., 2004). Both phases of the research
were co-funded by the BGS and the Mineral Industry Sustainable Technology Programme (MIST).
Environmental, economic and social information are essential for sustainable planning for the provision
of aggregates. There is a need to bring together disparate information relating to aggregate extraction.
Datasets include the location of resources and their potential end-uses, as well as those on the
environment and transport. Bringing this digital information together into one location or system will
assist in supporting a more balanced and informed approach to the decision making process. A number of
regulatory mechanisms are currently driving the gathering and compilation of relevant environmental,
economic and social information. Current drivers for information relevant to aggregate provision include
environmental appraisal of the provision of aggregates, SEA and Sustainability Appraisal (SA).
The objective of this research was to provide an interactive ‘tool’ or information system for the minerals
industry, land-use planners and other stakeholders to use when considering options for future aggregate
provision. The study area for the research was the East Midlands Region of England. The project had
three main deliverables:
1. To provide an online Geographic Information System (GIS) to access the ‘environmental
sensitivity’ map which was developed for the East Midlands Region during the first phase of
research;
2. to compile aggregate end-use suitability maps for the East Midland Region; and
3. to hold a stakeholder consultation exercise and dissemination seminars.
Each of these was met within the agreed timeframe. The environmental sensitivity map information and
associated attributes have been made available on the internet via the BGS ‘Minerals information online’
web GIS for the East Midlands Region (www.mineralsuk.com/web_gis). Accommodating these data in a
web GIS environment has entailed some compromises on data resolution and system functionality.
A methodology has been developed to integrate a range of aggregate technical property data. This can be
used to summarise the distribution of aggregate resources suitable for particular end-uses. These summary
technical data are useful in communicating issues of variable aggregate quality and economic value to
non-technical stakeholders in the mineral planning process. Availability of appropriate technical property
data for different aggregate resources across a wide geographical area is critical in developing these maps.
Feedback from an extensive consultation and dissemination exercise has generally been very positive.
Two critiques by independent consultants of the environmental sensitivity map were also undertaken.
These were deemed an important aspect of the consultation process. Stakeholders raised several issues.
There were some concerns about updating and maintenance of asset data and about the lack of social
information. In addition, some fundamental issues of approach (particularly asset weighting) raised in the
previous phase of this research resurfaced during this consultation.
Environmental sensitivity mapping will be carried out for the whole of England by the BGS in the near
future. The data will be made available online as each region becomes available. It is anticipated that the
mineral GISs for all regions of England (except London) will be completed by December 2005. New
datasets may be added to the environmental sensitivity layer as they become available. The research into
end-use suitability maps will be carried on by the BGS under its Minerals Programme, with the support of
co-funding where possible. The project team continue to welcome feedback and criticism of this research
Search for Gravitational Waves Associated with Gamma-Ray Bursts Detected by Fermi and Swift during the LIGO-Virgo Run O3b
We search for gravitational-wave signals associated with gamma-ray bursts (GRBs) detected by the Fermi and Swift satellites during the second half of the third observing run of Advanced LIGO and Advanced Virgo (2019 November 1 15:00 UTC-2020 March 27 17:00 UTC). We conduct two independent searches: A generic gravitational-wave transients search to analyze 86 GRBs and an analysis to target binary mergers with at least one neutron star as short GRB progenitors for 17 events. We find no significant evidence for gravitational-wave signals associated with any of these GRBs. A weighted binomial test of the combined results finds no evidence for subthreshold gravitational-wave signals associated with this GRB ensemble either. We use several source types and signal morphologies during the searches, resulting in lower bounds on the estimated distance to each GRB. Finally, we constrain the population of low-luminosity short GRBs using results from the first to the third observing runs of Advanced LIGO and Advanced Virgo. The resulting population is in accordance with the local binary neutron star merger rate. © 2022. The Author(s). Published by the American Astronomical Society
Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run
Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo's third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those inferred from electromagnetic observations. We find no evidence for continuous gravitational waves, and set upper limits on the strain amplitude for each target. These limits are more constraining for seven of the targets than the spin-down limit defined by ascribing all rotational energy loss to gravitational radiation. In an additional search, we look in O3 data for long-duration (hours-months) transient gravitational waves in the aftermath of pulsar glitches for six targets with a total of nine glitches. We report two marginal outliers from this search, but find no clear evidence for such emission either. The resulting duration-dependent strain upper limits do not surpass indirect energy constraints for any of these targets. © 2022. The Author(s). Published by the American Astronomical Society
GW190814: gravitational waves from the coalescence of a 23 solar mass black hole with a 2.6 solar mass compact object
We report the observation of a compact binary coalescence involving a 22.2–24.3 Me black hole and a compact object with a mass of 2.50–2.67 Me (all measurements quoted at the 90% credible level). The gravitational-wave signal, GW190814, was observed during LIGO’s and Virgo’s third observing run on 2019 August 14 at 21:10:39 UTC and has a signal-to-noise ratio of 25 in the three-detector network. The source was localized to 18.5 deg2 at a distance of - + 241 45
41 Mpc; no electromagnetic counterpart has been confirmed to date. The source has the most unequal mass ratio yet measured with gravitational waves, - + 0.112 0.009 0.008, and its secondary component is either the lightest black hole or the heaviest neutron star ever discovered in a double compact-object system. The
dimensionless spin of the primary black hole is tightly constrained to �0.07. Tests of general relativity reveal no measurable deviations from the theory, and its prediction of higher-multipole emission is confirmed at high confidence. We estimate a merger rate density of 1–23 Gpc−3 yr−1 for the new class of binary coalescence sources
that GW190814 represents. Astrophysical models predict that binaries with mass ratios similar to this event can form through several channels, but are unlikely to have formed in globular clusters. However, the combination of mass ratio, component masses, and the inferred merger rate for this event challenges all current models of the formation and mass distribution of compact-object binaries
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