scholarly journals Chapter 1: Structural Geology Applied to the Evaluation of Hydrothermal Gold Deposits

2020 ◽  
pp. 1-23
Author(s):  
T. G. Blenkinsop ◽  
N.H.S. Oliver ◽  
P.G.H.M. Dirks ◽  
M. Nugus ◽  
G. Tripp ◽  
...  
Keyword(s):  
Structural Geology ◽  
Gold Deposits

Chapter 1: Gold Deposit Types: An Overview

2020 ◽  
pp. 1-28
Author(s):  
Richard H. Sillitoe
Keyword(s):  
Gold Deposit ◽  
Unknown Origin ◽  
Mafic Magma ◽  
Massive Sulfide ◽  
Gold Deposits ◽  
Hydrothermal Fluids ◽  
Copper Gold ◽  
Deposit Type ◽  
Ambient Surface

Abstract Gold is either the only economically important metal or a major by-product in 11 well-characterized deposit types—paleoplacer, orogenic, porphyry, epithermal, Carlin, placer, reduced intrusion related, volcanogenic massive sulfide (VMS), skarn, carbonate replacement, and iron oxide-copper-gold (IOCG), arguably more than for those of any other metal; it also dominates a number of deposits of uncertain or unknown origin. Major gold concentrations formed worldwide from the Mesoarchean to the Pleistocene, from Earth’s surface to midcrustal paleodepths, alone or in association with silver, base metals, and/or uranium, and from hydrothermal fluids of predominantly metamorphic, magmatic, meteoric, seawater, or, uncommonly, basinal origins, as well as from mafic magma or ambient surface water. Most of the Neoproterozoic and Phanerozoic deposits unequivocally formed in accretionary orogens. As an introduction to this compilation of the world’s major gold deposits and provinces, this paper provides a thumbnail sketch of each gold deposit type, including geologic and economic characteristics and widely accepted genetic models, as well as briefly discusses aspects of their spatial and temporal associations and distributions.

Quick Reference: Chapter 1: The Musculoskeletal System: The Hand and Upper Extremity

2000 ◽  
Vol 5 (5) ◽  
pp. 4-5
Keyword(s):  
Dorsal Column ◽  
Persistent Pain ◽  
Illness Behavior ◽  
Abnormal Illness Behavior ◽  
Organ Systems ◽  
Spinal Cord Dorsal ◽  
Objective Basis ◽  
Dorsal Column Stimulation ◽  
Underlying Pathology

Abstract Spinal cord (dorsal column) stimulation (SCS) and intraspinal opioids (ISO) are treatments for patients in whom abnormal illness behavior is absent but who have an objective basis for severe, persistent pain that has not been adequately relieved by other interventions. Usually, physicians prescribe these treatments in cancer pain or noncancer-related neuropathic pain settings. A survey of academic centers showed that 87% of responding centers use SCS and 84% use ISO. These treatments are performed frequently in nonacademic settings, so evaluators likely will encounter patients who were treated with SCS and ISO. Does SCS or ISO change the impairment associated with the underlying conditions for which these treatments are performed? Although the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides) does not specifically address this question, the answer follows directly from the principles on which the AMA Guides impairment rating methodology is based. Specifically, “the impairment percents shown in the chapters that consider the various organ systems make allowance for the pain that may accompany the impairing condition.” Thus, impairment is neither increased due to persistent pain nor is it decreased in the absence of pain. In summary, in the absence of complications, the evaluator should rate the underlying pathology or injury without making an adjustment in the impairment for SCS or ISO.

Fifth Edition: the New Standard

2000 ◽  
Vol 5 (6) ◽  
pp. 1-7
Author(s):  
Christopher R. Brigham ◽  
James B. Talmage ◽  
Leon H. Ensalada
Keyword(s):  
Musculoskeletal System ◽  
Medical Information ◽  
Objective Assessment ◽  
Scientific Data ◽  
Practical Application ◽  
Fourth Edition ◽  
Appropriate Use ◽  
Medical Evaluation ◽  
Single Set

Abstract The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fifth Edition, is available and includes numerous changes that will affect both evaluators who and systems that use the AMA Guides. The Fifth Edition is nearly twice the size of its predecessor (613 pages vs 339 pages) and contains three additional chapters (the musculoskeletal system now is split into three chapters and the cardiovascular system into two). Table 1 shows how chapters in the Fifth Edition were reorganized from the Fourth Edition. In addition, each of the chapters is presented in a consistent format, as shown in Table 2. This article and subsequent issues of The Guides Newsletter will examine these changes, and the present discussion focuses on major revisions, particularly those in the first two chapters. (See Table 3 for a summary of the revisions to the musculoskeletal and pain chapters.) Chapter 1, Philosophy, Purpose, and Appropriate Use of the AMA Guides, emphasizes objective assessment necessitating a medical evaluation. Most impairment percentages in the Fifth Edition are unchanged from the Fourth because the majority of ratings currently are accepted, there is limited scientific data to support changes, and ratings should not be changed arbitrarily. Chapter 2, Practical Application of the AMA Guides, describes how to use the AMA Guides for consistent and reliable acquisition, analysis, communication, and utilization of medical information through a single set of standards.

Structural Geology: A Quantitative Introduction

2020 ◽  
Author(s):  
David D. Pollard ◽  
Stephen J. Martel
Keyword(s):  
Structural Geology

Chapter 1

2019 ◽  
Author(s):  
Servicio Geológico Colombiano SGC

Studi Awal Geologi di Daerah Beruang Kanan Kabupaten Gunung Mas Propinsi Kalimantan Tengah

PROMINE ◽  
2018 ◽  
Vol 6 (1) ◽  
pp. 1-11
Author(s):  
Retno Anjarwati ◽  
Arifudin Idrus ◽  
Lucas Donny Setijadji
Keyword(s):  
Gold Mineralization ◽  
Volcanic Rocks ◽  
Gold Deposits ◽  
Central Kalimantan ◽  
Magmatic Arc ◽  
Tertiary Sediment ◽  
Copper Gold ◽  
Regional Tectonic ◽  
Mineralization Processes ◽  
High Yields

The regional tectonic conditions of the KSK Contract of Work are located in the mid-Tertiary magmatic arc (Carlile and Mitchell, 1994) which host a number of epithermal gold deposits (eg, Kelian, Indon, Muro) and significant prospects such as Muyup, Masupa Ria, Gunung Mas and Mirah. Copper-gold mineralization in the KSK Contract of Work is associated with a number of intrusions that have occupied the shallow-scale crust at the Mesozoic metamorphic intercellular junction to the south and continuously into the Lower Tertiary sediment toward the water. This intrusion is interpreted to be part of the Oligocene arc of Central Kalimantan (in Carlile and Mitchell 1994) Volcanic rocks and associated volcanoes are older than intrusions, possibly aged Cretaceous and exposed together with all three contacts (Carlile and Mitchell, 1994) some researchers contribute details about the geological and mineralogical background, and some papers for that are published for the Beruang Kanan region and beyond but no one can confirm the genesis type of the Beruang Kanan region The mineralization of the Beruang Kanan area is generally composed by high yields of epithermal sulphide mineralization. with Cu-Au mineralization This high epithermal sulphide deposition coats the upper part of the Cu-Au porphyry precipitate associated with mineralization processes that are generally controlled by the structure

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