Granodiorite is a plutonic rock composed of black biotite, dark-gray hornblende, off-white plagio... more Granodiorite is a plutonic rock composed of black biotite, dark-gray hornblende, off-white plagioclase, and translucent gray quartz. Granodiorite differs from diorite by the presence of quartz, and the predominance of plagioclase over alkali feldspar distinguishes it from granite. Although it isn't true granite, granodiorite is one of the granitoid rocks. Rusty colors reflect weathering of rare grains of pyrite, which releases iron. The random orientation of grains shows that this is a plutonic rock.
It has become accepted in recent years that the fossil record can preserve labile tissues. We rep... more It has become accepted in recent years that the fossil record can preserve labile tissues. We report here the highly detailed mineralization of soft tissues associated with a naturally occurring brain endocast of an iguanodontian dinosaur found in c. 133 Ma fluvial sediments of the Weal-den at Bexhill, Sussex, UK. Moulding of the braincase wall and the mineral replacement of the adjacent brain tissues by phosphates and carbonates allowed the direct examination of petrified brain tissues. Scanning electron microscopy (SEM) imaging and computed tomography (CT) scanning revealed preservation of the tough membranes (meninges) that enveloped and supported the brain proper. Collagen strands of the meningeal layers were preserved in collophane. The blood vessels , also preserved in collophane, were either lined by, or infilled with, microcrystalline siderite. The meninges were preserved in the hindbrain region and exhibit structural similarities with those of living archosaurs. Greater definition of the forebrain (cerebrum) than the hindbrain (cere-bellar and medullary regions) is consistent with the anatomical and implied behavioural complexity previously described in iguanodontian-grade ornithopods. However, we caution that the observed proximity of probable cortical layers to the braincase walls probably resulted from the settling of brain tissues against the roof of the braincase after inversion of the skull during decay and burial.
The discovery of Entelognathus revealed the presence of maxilla, premaxilla, and dentary, suppose... more The discovery of Entelognathus revealed the presence of maxilla, premaxilla, and dentary, supposedly diagnostic osteichthyan bones, in a Silurian placoderm. However, the relationship between these marginal jaw bones and the gnathal plates of conventional placoderms, thought to represent the inner dental arcade, remains uncertain. Here we report a second Silurian maxillate placoderm, which bridges the gnathal and maxillate conditions. We propose that the maxilla, premaxilla, and dentary are homologous to the gnathal plates of placoderms and that all belong to the same dental arcade. The gnathal-maxillate transformation occurred concurrently in upper and lower jaws, predating the addition of infradentary bones to the lower jaw.
Journal of Vertebrate Paleontology Publication details, including instructions for authors and su... more Journal of Vertebrate Paleontology Publication details, including instructions for authors and subscription information:
Sediments and sedimentary rocks are an important, but unfortunately an often-ignored, aspect of p... more Sediments and sedimentary rocks are an important, but unfortunately an often-ignored, aspect of petroleum geology and hence petroleum recovery operations. Knowledge of the geology and mineralogy of a reservoir or deposit leads to deriving the means by which to find and penetrate the reservoir (or deposit), which would be sorely lacking and, most likely, cause problems for recovery. In addition, such knowledge is advantageous when in situ upgrading is considered as a process option during recovery. The minerals might well (hopefully) exhibit beneficial catalytic activity on the in situ upgrading process or, on the other hand, the minerals might have an adverse effect on the process chemistry and physics. It is the purpose of this chapter to introduce the reader to the concept of sediments, reservoirs, and deposits and the means by which these geological features originate and are formed.
A review of the more important aspects of geology with respect to petrophysics. A concise descrip... more A review of the more important aspects of geology with respect to petrophysics. A concise description of the origins of the principle types of sedimentary rocks associated with petroleum that supply the reserves for petroleum is provided. This is followed by theories on the origins of petroleum hydrocarbons, their migrations (sometimes over unusually long distances) to geologic traps where they establish the reservoirs of petroleum. The chapter ends with a discussion of the nature of the subsurface environments where petroleum is found and the properties and chemistry of petroleum and its products.
This chapter describes the internal megascopic features of a sediment. These are termed sedimenta... more This chapter describes the internal megascopic features of a sediment. These are termed sedimentary structures, and are distinguished from the microscopic structural features of a sediment. Sedimentary structures are divided into primary and secondary classes. Primary structures are those generated in a sediment during or shortly after deposition, whereas secondary sedimentary structures are those that form sometime after sedimentation. The chapter discusses various examples of both primary and secondary structures. Primary sedimentary structures are divisible into inorganic structures, and organic structures. The observation, interpretation, and classification of inorganic sedimentary structures are considered. The chapter describes two basic approaches to observe sedimentary structures. The first approach is to pretend the outcrop is a borehole and to measure a detailed sedimentological log. This records a vertical section of limited lateral extent. The second method is to create a two-dimensional survey of all, or a major part, of the outcrop.
Documentation of structures in different scales is the first step in many structural geological s... more Documentation of structures in different scales is the first step in many structural geological studies. This edited atlas gives an overview of diverse structures. Due to lack of space or inappropriateness, sometimes interesting structural snaps cannot be published in journals. This book fills that gap.
Geophysics, as its name indicates, has to do with the physics of the earth and its atmosphere. Gi... more Geophysics, as its name indicates, has to do with the physics of the earth and its atmosphere. Gilbert's discovery that the earth behaves as a great and rather irregular magnet and Newton's theory of gravitation may be said to constitute the beginning of geophysics. the continued expansion in demand for metals of all kinds and the enormous increase in the use of petroleum products have led to the development of many geophysical techniques of ever-increasing sensitivity for the detection and mapping of unseen deposits and structures. because the great majority of mineral deposits are beneath the surface, their detection depends on those characteristics that differentiate them from the surrounding media. Methods based on variations in the elastic properties of rocks have been developed for determine structures associated with oil and gas, such as faults, anticlines, and sync lines several kilometers below the surface.
Petroleum geology is the application of geology (the study of rocks) to the exploration for and ... more Petroleum geology is the application of geology (the study of rocks) to the exploration for and production of oil and gas. Geology itself is strongly based on chemistry, physics and biology, involving the application of essentially abstract concepts to data. In the past these data were basically observational and subjective. Petroleum geology, in particular still rely on value judgments based on experience and an assessment of validity among the data presented. Exploration had advanced over the years as various geological techniques were developed.
The development of new technologies in the past 10 years, like the MWD systems for
real-time surv... more The development of new technologies in the past 10 years, like the MWD systems for real-time surveying, steerable systems for an effective control of trajectory, PDC bits for efficient drilling of long sections, mud and hydraulic systems for improved control of hole cleaning and borehole stability, etc. have transformed directional drilling into a common practice. There are a few serious problems which may arise during the course of drilling a directional well. The probability of certain drilling problems arising (e.g. differential sticking) is increased by virtue of the well being deviated. The causes and implications of differential sticking are discussed here, as well as solutions and possible preventive measures. This is very relevant to the DD, particularly in areas which are prone to differential sticking. Dog legs and key seats are discussed here in detail. As mentioned elsewhere in this manual, it is the DD’s responsibility to ascertain the client’s limit on dog leg severity at the beginning of the project. The consequences of high dog leg severity at a shallow depth often do not become apparent until much deeper in the well. Problems caused by borehole instability due to poor hydraulics and mud conditioning are outlined. Increases in Drag, particularly when drilling with a PDM, directly concern the DD. In high-angle wells, it often becomes very difficult to "slide".
Granodiorite is a plutonic rock composed of black biotite, dark-gray hornblende, off-white plagio... more Granodiorite is a plutonic rock composed of black biotite, dark-gray hornblende, off-white plagioclase, and translucent gray quartz. Granodiorite differs from diorite by the presence of quartz, and the predominance of plagioclase over alkali feldspar distinguishes it from granite. Although it isn't true granite, granodiorite is one of the granitoid rocks. Rusty colors reflect weathering of rare grains of pyrite, which releases iron. The random orientation of grains shows that this is a plutonic rock.
It has become accepted in recent years that the fossil record can preserve labile tissues. We rep... more It has become accepted in recent years that the fossil record can preserve labile tissues. We report here the highly detailed mineralization of soft tissues associated with a naturally occurring brain endocast of an iguanodontian dinosaur found in c. 133 Ma fluvial sediments of the Weal-den at Bexhill, Sussex, UK. Moulding of the braincase wall and the mineral replacement of the adjacent brain tissues by phosphates and carbonates allowed the direct examination of petrified brain tissues. Scanning electron microscopy (SEM) imaging and computed tomography (CT) scanning revealed preservation of the tough membranes (meninges) that enveloped and supported the brain proper. Collagen strands of the meningeal layers were preserved in collophane. The blood vessels , also preserved in collophane, were either lined by, or infilled with, microcrystalline siderite. The meninges were preserved in the hindbrain region and exhibit structural similarities with those of living archosaurs. Greater definition of the forebrain (cerebrum) than the hindbrain (cere-bellar and medullary regions) is consistent with the anatomical and implied behavioural complexity previously described in iguanodontian-grade ornithopods. However, we caution that the observed proximity of probable cortical layers to the braincase walls probably resulted from the settling of brain tissues against the roof of the braincase after inversion of the skull during decay and burial.
The discovery of Entelognathus revealed the presence of maxilla, premaxilla, and dentary, suppose... more The discovery of Entelognathus revealed the presence of maxilla, premaxilla, and dentary, supposedly diagnostic osteichthyan bones, in a Silurian placoderm. However, the relationship between these marginal jaw bones and the gnathal plates of conventional placoderms, thought to represent the inner dental arcade, remains uncertain. Here we report a second Silurian maxillate placoderm, which bridges the gnathal and maxillate conditions. We propose that the maxilla, premaxilla, and dentary are homologous to the gnathal plates of placoderms and that all belong to the same dental arcade. The gnathal-maxillate transformation occurred concurrently in upper and lower jaws, predating the addition of infradentary bones to the lower jaw.
Journal of Vertebrate Paleontology Publication details, including instructions for authors and su... more Journal of Vertebrate Paleontology Publication details, including instructions for authors and subscription information:
Sediments and sedimentary rocks are an important, but unfortunately an often-ignored, aspect of p... more Sediments and sedimentary rocks are an important, but unfortunately an often-ignored, aspect of petroleum geology and hence petroleum recovery operations. Knowledge of the geology and mineralogy of a reservoir or deposit leads to deriving the means by which to find and penetrate the reservoir (or deposit), which would be sorely lacking and, most likely, cause problems for recovery. In addition, such knowledge is advantageous when in situ upgrading is considered as a process option during recovery. The minerals might well (hopefully) exhibit beneficial catalytic activity on the in situ upgrading process or, on the other hand, the minerals might have an adverse effect on the process chemistry and physics. It is the purpose of this chapter to introduce the reader to the concept of sediments, reservoirs, and deposits and the means by which these geological features originate and are formed.
A review of the more important aspects of geology with respect to petrophysics. A concise descrip... more A review of the more important aspects of geology with respect to petrophysics. A concise description of the origins of the principle types of sedimentary rocks associated with petroleum that supply the reserves for petroleum is provided. This is followed by theories on the origins of petroleum hydrocarbons, their migrations (sometimes over unusually long distances) to geologic traps where they establish the reservoirs of petroleum. The chapter ends with a discussion of the nature of the subsurface environments where petroleum is found and the properties and chemistry of petroleum and its products.
This chapter describes the internal megascopic features of a sediment. These are termed sedimenta... more This chapter describes the internal megascopic features of a sediment. These are termed sedimentary structures, and are distinguished from the microscopic structural features of a sediment. Sedimentary structures are divided into primary and secondary classes. Primary structures are those generated in a sediment during or shortly after deposition, whereas secondary sedimentary structures are those that form sometime after sedimentation. The chapter discusses various examples of both primary and secondary structures. Primary sedimentary structures are divisible into inorganic structures, and organic structures. The observation, interpretation, and classification of inorganic sedimentary structures are considered. The chapter describes two basic approaches to observe sedimentary structures. The first approach is to pretend the outcrop is a borehole and to measure a detailed sedimentological log. This records a vertical section of limited lateral extent. The second method is to create a two-dimensional survey of all, or a major part, of the outcrop.
Documentation of structures in different scales is the first step in many structural geological s... more Documentation of structures in different scales is the first step in many structural geological studies. This edited atlas gives an overview of diverse structures. Due to lack of space or inappropriateness, sometimes interesting structural snaps cannot be published in journals. This book fills that gap.
Geophysics, as its name indicates, has to do with the physics of the earth and its atmosphere. Gi... more Geophysics, as its name indicates, has to do with the physics of the earth and its atmosphere. Gilbert's discovery that the earth behaves as a great and rather irregular magnet and Newton's theory of gravitation may be said to constitute the beginning of geophysics. the continued expansion in demand for metals of all kinds and the enormous increase in the use of petroleum products have led to the development of many geophysical techniques of ever-increasing sensitivity for the detection and mapping of unseen deposits and structures. because the great majority of mineral deposits are beneath the surface, their detection depends on those characteristics that differentiate them from the surrounding media. Methods based on variations in the elastic properties of rocks have been developed for determine structures associated with oil and gas, such as faults, anticlines, and sync lines several kilometers below the surface.
Petroleum geology is the application of geology (the study of rocks) to the exploration for and ... more Petroleum geology is the application of geology (the study of rocks) to the exploration for and production of oil and gas. Geology itself is strongly based on chemistry, physics and biology, involving the application of essentially abstract concepts to data. In the past these data were basically observational and subjective. Petroleum geology, in particular still rely on value judgments based on experience and an assessment of validity among the data presented. Exploration had advanced over the years as various geological techniques were developed.
The development of new technologies in the past 10 years, like the MWD systems for
real-time surv... more The development of new technologies in the past 10 years, like the MWD systems for real-time surveying, steerable systems for an effective control of trajectory, PDC bits for efficient drilling of long sections, mud and hydraulic systems for improved control of hole cleaning and borehole stability, etc. have transformed directional drilling into a common practice. There are a few serious problems which may arise during the course of drilling a directional well. The probability of certain drilling problems arising (e.g. differential sticking) is increased by virtue of the well being deviated. The causes and implications of differential sticking are discussed here, as well as solutions and possible preventive measures. This is very relevant to the DD, particularly in areas which are prone to differential sticking. Dog legs and key seats are discussed here in detail. As mentioned elsewhere in this manual, it is the DD’s responsibility to ascertain the client’s limit on dog leg severity at the beginning of the project. The consequences of high dog leg severity at a shallow depth often do not become apparent until much deeper in the well. Problems caused by borehole instability due to poor hydraulics and mud conditioning are outlined. Increases in Drag, particularly when drilling with a PDM, directly concern the DD. In high-angle wells, it often becomes very difficult to "slide".
This article deals with some geochemical parameters of some selected chemical data of the younger... more This article deals with some geochemical parameters of some selected chemical data of the younger granite of Egypt. The younger granites have a composition ranging from Alkali feldspar granite to syenogranites. the major oxides (FeO, CaO, MgO, Al2O3, MnO, Na2O) show symmetrical variation which indicated continuous variation and fractional crystallization from the pure magmatic melt. It was concluded that these rocks exhibit alkaline affinity and fractional crystallization from the magmatic melt. This younger granites are classified according to their geological setting and petrography to belong to Phase III which is mainly alkali granites. The younger granite of Egypt seems to be homogeneous chemically and mineralogically, unfoliated, hard resist weathering to a great extent. The relations between Al2O3 and SiO2 indicate that most investigated samples are post-orogenic granite(POG). These results are also confirmed by using the relation between (FeOt/FeOt+MgO) and SiO2 wt%.
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Granodiorite differs from diorite by the presence of quartz, and the predominance of plagioclase over alkali feldspar distinguishes it from granite. Although it isn't true granite, granodiorite is one of the granitoid rocks. Rusty colors reflect weathering of rare grains of pyrite, which releases iron. The random orientation of grains shows that this is a plutonic rock.
an overview of diverse structures. Due to lack of space or inappropriateness, sometimes interesting structural snaps cannot
be published in journals. This book fills that gap.
because the great majority of mineral deposits are beneath the surface, their detection depends on those characteristics that differentiate them from the surrounding media.
Methods based on variations in the elastic properties of rocks have been developed for determine structures associated with oil and gas, such as faults, anticlines, and sync lines several kilometers below the surface.
Geology itself is strongly based on chemistry, physics and biology, involving the application of essentially abstract concepts to data.
In the past these data were basically observational and subjective.
Petroleum geology, in particular still rely on value judgments based on experience and an assessment of validity among the data presented.
Exploration had advanced over the years as various geological techniques were developed.
real-time surveying, steerable systems for an effective control of trajectory, PDC bits for
efficient drilling of long sections, mud and hydraulic systems for improved control of
hole cleaning and borehole stability, etc. have transformed directional drilling into a
common practice.
There are a few serious problems which may arise during the course of drilling a
directional well. The probability of certain drilling problems arising (e.g. differential
sticking) is increased by virtue of the well being deviated. The causes and implications of
differential sticking are discussed here, as well as solutions and possible preventive
measures. This is very relevant to the DD, particularly in areas which are prone to
differential sticking.
Dog legs and key seats are discussed here in detail. As mentioned elsewhere in this
manual, it is the DD’s responsibility to ascertain the client’s limit on dog leg severity at
the beginning of the project. The consequences of high dog leg severity at a shallow
depth often do not become apparent until much deeper in the well.
Problems caused by borehole instability due to poor hydraulics and mud conditioning are
outlined. Increases in Drag, particularly when drilling with a PDM, directly concern the
DD. In high-angle wells, it often becomes very difficult to "slide".
Granodiorite differs from diorite by the presence of quartz, and the predominance of plagioclase over alkali feldspar distinguishes it from granite. Although it isn't true granite, granodiorite is one of the granitoid rocks. Rusty colors reflect weathering of rare grains of pyrite, which releases iron. The random orientation of grains shows that this is a plutonic rock.
an overview of diverse structures. Due to lack of space or inappropriateness, sometimes interesting structural snaps cannot
be published in journals. This book fills that gap.
because the great majority of mineral deposits are beneath the surface, their detection depends on those characteristics that differentiate them from the surrounding media.
Methods based on variations in the elastic properties of rocks have been developed for determine structures associated with oil and gas, such as faults, anticlines, and sync lines several kilometers below the surface.
Geology itself is strongly based on chemistry, physics and biology, involving the application of essentially abstract concepts to data.
In the past these data were basically observational and subjective.
Petroleum geology, in particular still rely on value judgments based on experience and an assessment of validity among the data presented.
Exploration had advanced over the years as various geological techniques were developed.
real-time surveying, steerable systems for an effective control of trajectory, PDC bits for
efficient drilling of long sections, mud and hydraulic systems for improved control of
hole cleaning and borehole stability, etc. have transformed directional drilling into a
common practice.
There are a few serious problems which may arise during the course of drilling a
directional well. The probability of certain drilling problems arising (e.g. differential
sticking) is increased by virtue of the well being deviated. The causes and implications of
differential sticking are discussed here, as well as solutions and possible preventive
measures. This is very relevant to the DD, particularly in areas which are prone to
differential sticking.
Dog legs and key seats are discussed here in detail. As mentioned elsewhere in this
manual, it is the DD’s responsibility to ascertain the client’s limit on dog leg severity at
the beginning of the project. The consequences of high dog leg severity at a shallow
depth often do not become apparent until much deeper in the well.
Problems caused by borehole instability due to poor hydraulics and mud conditioning are
outlined. Increases in Drag, particularly when drilling with a PDM, directly concern the
DD. In high-angle wells, it often becomes very difficult to "slide".