ഹാപ്പി ന്യൂസ് !
കഴിഞ്ഞ ക്രയ വീക്സ് ആയി കാണാന് illada ഇരുന്ന എന്ടെ സ്വന്തം പൂച്ച തിരിച്ചു വന്നു !
:)
ഐ was
Monday, August 11, 2008
Wednesday, July 09, 2008
മലയാളം അറിയാം പക്ഷെ എങ്ങിനെ ടൈപ്പ് ചെയും എന്ന് അല്ലോചിച്ചു സമയം പോയി ഇനി ഇംഗ്ലീഷ് ആകാം ടൈപ്പ് !
ende kartave ee malayalatil type chyan itra kandu padano /
hmmm
endayallum adutatayi inni !
oru calicut to wayanad yatra yum adil kanda kazhchayum anu vishahayam !
so next in line is the trip from calicut to wayanad and the photos form the trip !
ഇവിടെയും മലയാളം എനിക് തുണയാകും എന്ന് തോന്നില്ല എന്ടയല്ലും ശെരി
ഇനി കഴിയുനടും മലയാളം ഉപയോകികാന് ശ്രമികാം
:)
ende kartave ee malayalatil type chyan itra kandu padano /
hmmm
endayallum adutatayi inni !
oru calicut to wayanad yatra yum adil kanda kazhchayum anu vishahayam !
so next in line is the trip from calicut to wayanad and the photos form the trip !
ഇവിടെയും മലയാളം എനിക് തുണയാകും എന്ന് തോന്നില്ല എന്ടയല്ലും ശെരി
ഇനി കഴിയുനടും മലയാളം ഉപയോകികാന് ശ്രമികാം
:)
Sunday, May 18, 2008
iravangi puzhayude teeram ennum eniku priyapetatayirunu !have spent count less evenings in the sandy shores of this river !
a place to relax ur self !
calm and quite !
cooling breezee !
every thing there was magical !
still remember the days we four goes to attend the sivratri festival in the temple in middle of this eravanchi puza ! this year all of that childhood stuff came back as once more time we went to attend the sivratri festival there only difference where this time my dear Bro was not with me to so we three went to .......... !
Tuesday, April 29, 2008
Flocks its time for a poem i think so ! coz my posts are not moving like it was before so now really ! the situation calls for me to or compelled me to write this poem !
Song to a Petalite changing to a Ruby *
U R a petalite in my sweet dreams
Precious with purity in love's full embrace
So U tosses & U turn soul shining & old
U R a petalite in my sweet dreams
An ornament perhaps, a ring
U will be when its time
Adored by HIS smile
HIS love endures as the tide
Watch, Wait a while...........................
U R a petalite in my sweet dreams
Keep still Until, I .......... or ............ ?
it will be revealed to U
Sooner or later after all
U R a petalite in my sweet dreams
Heart glowing , soul knowing of what you have been
What U will be ,,,,,,,,,,,,
Who R U ? ? ?
HIS secrets R near & Far
With time, love & care, U will become a RUBY! !
Sunday, March 16, 2008
Friday, February 01, 2008
St: Thomas Ferona Church Annual Feast ! Thottumukkom ....
Light decorations make the church a real must see sight !
Anna vadil or the main entrance to church !
Inside church !
Feast decorations !
ende idavaga palli perunall kudan nyan poyi !
perunal kuudan vendi Irvin 2 divasam leave edutu nattil chennu ! avide kanda kazhchakall annu ivide itirikunadu engane undu !
Light decorations make the church a real must see sight !
Anna vadil or the main entrance to church !
Inside church !
Feast decorations !ende idavaga palli perunall kudan nyan poyi !
perunal kuudan vendi Irvin 2 divasam leave edutu nattil chennu ! avide kanda kazhchakall annu ivide itirikunadu engane undu !
Tuesday, January 22, 2008
Saturday, January 19, 2008
Friday, January 18, 2008
Thursday, January 17, 2008
Friday, January 11, 2008
Wednesday, January 09, 2008
Saturday, December 22, 2007
Resolution
for this Christmas !
Can God Use You?
Noah was a drunk
Abraham was too old
Isaac was a daydreamer
Jacob was a liar
Leah was ugly
Joseph was abused
Moses had a stuttering problem
Gideon was afraid
Sampson had long hair and was a womanizer
Rahab was a prostitute
Jeremiah and Timothy were too young
David had an affair and was a murderer
Elijah was suicidal
Isaiah preached naked
Jonah ran from God
Naomi was a widow
Job went bankrupt
John the Baptist ate bugs
Peter denied Christ
The Disciples fell asleep while praying
Martha worried about everything
The Samaritan woman was divorced, more than once
Zaccheus was too small
Paul was too religious
Timothy had an ulcer...AND
Lazarus was dead!
No more excuses now.
God can use you to your full
potential. Besides you aren't the message,
you
are just the messenger.
Share this with a friend or two...
In the Circle of God's love!
"God does not want your ability...
all he wants is your availability.
You say YES, God will do the rest!”
so friends this christmas
lets offer ourselfs to god !
let his plans work on us !
praise the lord !
Thursday, December 20, 2007
Friday, December 07, 2007
Thursday, December 06, 2007
Saturday, December 01, 2007
Wednesday, November 28, 2007
Friday, November 23, 2007
Tuesday, November 20, 2007
Sunday, November 11, 2007
Saturday, November 10, 2007
Enna parayuka ! enikku kavitha varunu ! nyan chollate !
here is my Hindi Shayari ! like it tell me dont like it then also tell me ! oke
Shayar by Irvin Sabastian
Pal do pal ka jeevan hai !
isi mein waqt kaha
pal do pal ka jeevan hai !
isi mein waqt kaha !
Nafrat ke liye !
Dushmani ke liye !
Avo hum pyar kare !
Payar hi such hai jeevan mein ...
baki sab mithya hai !
here is my Hindi Shayari ! like it tell me dont like it then also tell me ! oke
Shayar by Irvin Sabastian
Pal do pal ka jeevan hai !
isi mein waqt kaha
pal do pal ka jeevan hai !
isi mein waqt kaha !
Nafrat ke liye !
Dushmani ke liye !
Avo hum pyar kare !
Payar hi such hai jeevan mein ...
baki sab mithya hai !
Friday, November 09, 2007
Saturday, October 27, 2007
Sunday, September 30, 2007
Sunday, September 23, 2007
I alway dream of being a fish ! to roam free in the endless great waters ! which covers more than land ! being mere mortal seems so boring and i want to break the shackels which is invisible and yet so powerful ! ......... iam i out of my mind @ dont know
any way i will be posting some of my photos from thusharagiri trip ! wait and watch irvin sabastian in action !
style defines more @ you will agree !
any way i will be posting some of my photos from thusharagiri trip ! wait and watch irvin sabastian in action !
style defines more @ you will agree !
Thursday, August 30, 2007
Monday, August 13, 2007
Monday, July 23, 2007
Sunday, July 22, 2007
Saturday, June 30, 2007
Thursday, May 17, 2007
Friday, May 04, 2007
i am in a bit of hurry so the rest of the eras left are posted here feel free to check out !
Paleozoic Era
Early in the 300 million year history of the Paleozoic, atmospheric oxygen reached its present levels, generating the ozone shield that screens out ultraviolet radiation and allows complex life to live in the shallows and finally on land. This era witnessed the age of invertebrates, of fish, of tetrapods, and (during the Permian) reptiles. From the Silurian on, life emerged from the sea to colonize the land, and in the later Paleozoic pteridophyte and later gymnospermous plants flourished. The generally mild to tropical conditions with their warm shallow seas were interspersed with Ordovician and Permo-Carboniferous ice ages. Towards the end of the Paleozoic the continents clustered into the supercontinent of Pangea, and increasingly aridity meant the end of the great Carboniferous swamps and their unique flora and fauna. The Paleozoic was brought to an end by the end Permian mass-extinction, perhaps the most severe extinction the planet has seen.
Mesozoic Era
Lasting little more than half the duration of the Paleozoic, this was a spectacular time. The generalized archosaurian reptiles of the Triassic gave way to the dinosaurs, a terrestrial megafauna the like of which the Earth has not seen before or since. While dinosaurs dominated the land, diverse sea-reptiles ruled the oceans, and invertebrates, especially ammonites, were extremely diverse. Pterosaurs and later birds took to the sky. Mammals however remained small and insignificant. Climatic conditions remained warm and tropical worldwide. The supercontinent of Pangea broke up into Laurasia and Gondwana, with different dinosaurian faunas evolving on each. During this era modern forms of corals, insects, new fishes and finally flowering plants evolved. At the end of the Cretaceous period the dinosaurs and many other animals abruptly died out, quite likely the result of an asteroid impact and associated extensive volcanism (acid rain)
Cenozoic Era
With the extinction of the dinosaurs and the end of the Mesozoic, the mammals swiftly inherit the Earth. Archaic mammals co-existed with birds and modern reptiles and invertebrates. The current continents emerged, and the initial tropical conditions were replaced by a colder drier climate, possibly caused by the Himalayan uplift. The appearance of grass meant the rise of grazing mammals, and the cooler drier world allowed modern mammalian groups to evolve, along with other lineages now extinct and a few archaic hold-overs. Among the newcomers were the anthropoid apes that culminated in the australopithecine hominids of Africa. Decreasing temperatures and a polar landmass of Antarctica resulted in a new Ice Age. Most recently, in the blink of an eye geologically speaking, this era saw the rise of Man (Homo erectus, Neanderthal and Cro Magnon) and use of stone tools and fire, the extinction of Megafauna, and civilization and human activities that have transformed the globe, but at a cost of great environmental destruction.
cenozoic era is the era in which we are living so keep in mind we are making its history now !
Paleozoic Era
Early in the 300 million year history of the Paleozoic, atmospheric oxygen reached its present levels, generating the ozone shield that screens out ultraviolet radiation and allows complex life to live in the shallows and finally on land. This era witnessed the age of invertebrates, of fish, of tetrapods, and (during the Permian) reptiles. From the Silurian on, life emerged from the sea to colonize the land, and in the later Paleozoic pteridophyte and later gymnospermous plants flourished. The generally mild to tropical conditions with their warm shallow seas were interspersed with Ordovician and Permo-Carboniferous ice ages. Towards the end of the Paleozoic the continents clustered into the supercontinent of Pangea, and increasingly aridity meant the end of the great Carboniferous swamps and their unique flora and fauna. The Paleozoic was brought to an end by the end Permian mass-extinction, perhaps the most severe extinction the planet has seen.
Mesozoic Era
Lasting little more than half the duration of the Paleozoic, this was a spectacular time. The generalized archosaurian reptiles of the Triassic gave way to the dinosaurs, a terrestrial megafauna the like of which the Earth has not seen before or since. While dinosaurs dominated the land, diverse sea-reptiles ruled the oceans, and invertebrates, especially ammonites, were extremely diverse. Pterosaurs and later birds took to the sky. Mammals however remained small and insignificant. Climatic conditions remained warm and tropical worldwide. The supercontinent of Pangea broke up into Laurasia and Gondwana, with different dinosaurian faunas evolving on each. During this era modern forms of corals, insects, new fishes and finally flowering plants evolved. At the end of the Cretaceous period the dinosaurs and many other animals abruptly died out, quite likely the result of an asteroid impact and associated extensive volcanism (acid rain)
Cenozoic Era
With the extinction of the dinosaurs and the end of the Mesozoic, the mammals swiftly inherit the Earth. Archaic mammals co-existed with birds and modern reptiles and invertebrates. The current continents emerged, and the initial tropical conditions were replaced by a colder drier climate, possibly caused by the Himalayan uplift. The appearance of grass meant the rise of grazing mammals, and the cooler drier world allowed modern mammalian groups to evolve, along with other lineages now extinct and a few archaic hold-overs. Among the newcomers were the anthropoid apes that culminated in the australopithecine hominids of Africa. Decreasing temperatures and a polar landmass of Antarctica resulted in a new Ice Age. Most recently, in the blink of an eye geologically speaking, this era saw the rise of Man (Homo erectus, Neanderthal and Cro Magnon) and use of stone tools and fire, the extinction of Megafauna, and civilization and human activities that have transformed the globe, but at a cost of great environmental destruction.
cenozoic era is the era in which we are living so keep in mind we are making its history now !
Thursday, April 12, 2007
Proterozoic Era
The Proterozoic, which lasted even longer than the Archean Era, saw the atmosphere changes from reducing to oxygenated, driving the original anaerobic inhabitants of the Earth into a few restricted anoxic refuges and enabling the rise of aerobic life (both prokaryote and the more complex eukaryotic cell, which requires the high octane boost that oxygen enables.) Stromatolites (colonial cyanobacteria), which had appeared during the Archean, were common. The modern regime of continental drift began, and saw the formation of supercontinent of Rodinia, and several extensive ice ages. Late in the Proterozoic a runaway icehouse effect meant that the preceding warm conditions were replaced by a "snowball" with ice several kilometers deep covering the globe. Warming conditions saw the short-lived Edicarian biota and finally the appearance of first metazoa.
The Proterozoic, which lasted even longer than the Archean Era, saw the atmosphere changes from reducing to oxygenated, driving the original anaerobic inhabitants of the Earth into a few restricted anoxic refuges and enabling the rise of aerobic life (both prokaryote and the more complex eukaryotic cell, which requires the high octane boost that oxygen enables.) Stromatolites (colonial cyanobacteria), which had appeared during the Archean, were common. The modern regime of continental drift began, and saw the formation of supercontinent of Rodinia, and several extensive ice ages. Late in the Proterozoic a runaway icehouse effect meant that the preceding warm conditions were replaced by a "snowball" with ice several kilometers deep covering the globe. Warming conditions saw the short-lived Edicarian biota and finally the appearance of first metazoa.
Monday, April 02, 2007
ARCHEAN ERA
Lasting more than twice as long as the Phanerozoic eon, the Archean was a time when diverse microbial life flourished in the primordial oceans, and the continental shields developed from volcanic activity. The reducing (anaerobic) atmosphere enabled archea (anaerobic microbes) to develop, and plate tectonics followed a regime of continental drift different to that of the Proterozoic and later. During this era, one type of organism, the Cyanobacteria (blue-green algae) produced oxygen as a metabolic by-product; the eventual build-up of this highly reactive gas was to eventually prove fatal to many life-forms, and converted the atmosphere from.
HU I WONDER WHAT THE NEXT ERA WOULD BE /////// ! ?
Lasting more than twice as long as the Phanerozoic eon, the Archean was a time when diverse microbial life flourished in the primordial oceans, and the continental shields developed from volcanic activity. The reducing (anaerobic) atmosphere enabled archea (anaerobic microbes) to develop, and plate tectonics followed a regime of continental drift different to that of the Proterozoic and later. During this era, one type of organism, the Cyanobacteria (blue-green algae) produced oxygen as a metabolic by-product; the eventual build-up of this highly reactive gas was to eventually prove fatal to many life-forms, and converted the atmosphere from.
HU I WONDER WHAT THE NEXT ERA WOULD BE /////// ! ?
Tuesday, March 27, 2007
HADEAN ERA
This era begins with the formation of the Solar System and Earth, outgassing of first atmosphere and oceans, bombardment by left-over planetessimals and debris. The name says it all; a hellish period lasting some 760 million years, when the Earth was subject to frequent bombardment by comets, asteroids, and other planetary debris. At one point, early in this era the moon was formed when a Mars-sized body struck the original Earth, pulverizing both. Yet incredibly, the first primitive life emerged even at this early stage. This was an era characterized by extensive volcanism and formation of first continents. By the end of the Hadean, the Earth had an atmosphere (unbreathable to most organisms today), and oceans filled with prokaryote life evolution ........ the begining got it ! lets see what next era is in my next blog !
This era begins with the formation of the Solar System and Earth, outgassing of first atmosphere and oceans, bombardment by left-over planetessimals and debris. The name says it all; a hellish period lasting some 760 million years, when the Earth was subject to frequent bombardment by comets, asteroids, and other planetary debris. At one point, early in this era the moon was formed when a Mars-sized body struck the original Earth, pulverizing both. Yet incredibly, the first primitive life emerged even at this early stage. This was an era characterized by extensive volcanism and formation of first continents. By the end of the Hadean, the Earth had an atmosphere (unbreathable to most organisms today), and oceans filled with prokaryote life evolution ........ the begining got it ! lets see what next era is in my next blog !
Sunday, March 25, 2007
NOW ITS going to be geological time scale about the past eras and the present era !
first let me tell u guys what is geological time scale
The Geological Time Scale
Scientists divide the Earth into a number of periods - the "geological time scale according to the rock types and sort of fossils found in each one. These divisions are pretty arbitrary, like any man-made divisions, but they at least can serve as useful labels. So the Paleozoic, the era of "ancient life" is characterized by fossils of invertebrates, primitive tetrapods, etc; the Mesozoic or era of "middle life", by fossils of dinosaurs etc, and the Cenozoic or era of "recent life" by mammals and modern plants and invertebrates.
These eras are divided into periods, the system of which was established by the end of the last century. The periods are in turn divided into epochs, and the epochs are divided into ages called ages.
Scientists know these periods lasted for millions of years, because they can date them with a fair degree of accuracy according to the amount of radioactivity that occurs in the rocks.
The geological time scale can also be used to define the major stages in the history of life on Earth. Often each era ends with a major extinction, which eliminates the dominant life forms of the time and paves the way for newcomers
first let me tell u guys what is geological time scale
The Geological Time Scale
Scientists divide the Earth into a number of periods - the "geological time scale according to the rock types and sort of fossils found in each one. These divisions are pretty arbitrary, like any man-made divisions, but they at least can serve as useful labels. So the Paleozoic, the era of "ancient life" is characterized by fossils of invertebrates, primitive tetrapods, etc; the Mesozoic or era of "middle life", by fossils of dinosaurs etc, and the Cenozoic or era of "recent life" by mammals and modern plants and invertebrates.
These eras are divided into periods, the system of which was established by the end of the last century. The periods are in turn divided into epochs, and the epochs are divided into ages called ages.
Scientists know these periods lasted for millions of years, because they can date them with a fair degree of accuracy according to the amount of radioactivity that occurs in the rocks.
The geological time scale can also be used to define the major stages in the history of life on Earth. Often each era ends with a major extinction, which eliminates the dominant life forms of the time and paves the way for newcomers
Monday, March 19, 2007
i think the dinosaur fever is all done ! now is the time for me tot change my subject as usual next subject in on the search ! as soon as i find one i will start blogging on it ! ok ! if any of you know a better subject or a suggestion on what to start next ! please let me know iam clueless ! so the past week was a busy one
we had a international conference to attend UROLAPCON 2007 ! boy that was a task i say ! it was on advanced lap procedures in intra renal surgery ! a live work shop ! many renowned surgeons and urologist attended the conferernce and it was a huge sucess ! the whole conf! was on KADAVU RESORT calicut ! 3 days were flying actually ! bye until i gets new inspiration !
we had a international conference to attend UROLAPCON 2007 ! boy that was a task i say ! it was on advanced lap procedures in intra renal surgery ! a live work shop ! many renowned surgeons and urologist attended the conferernce and it was a huge sucess ! the whole conf! was on KADAVU RESORT calicut ! 3 days were flying actually ! bye until i gets new inspiration !
Wednesday, March 07, 2007
after reveling all the secrets of dinosaurs this cretaceous beast is really mad at me its time to escape ! -- from what the bordem that often envelop me or in to the cool world out side ! hey one thing i for got i have started orkuting recently some one month ago think it will be great place to shed my bordem and loneliness
Saturday, March 03, 2007
Cretaceous Stratigraphy
Period
Epoch (ICS, with added subdivision)
Harland Epoch
Age
ICS Base
ICS Duration
Paleogene
Paleocene: 9.7 My
Paleocene
Danian
65.5
3.8
Cretaceous80.0 My
Late Cretaceous II(End-Cretaceous)18.0 My
Senonian
Maastrichtian
70.6
5.1
Campanian
83.5
12.9
Late Cretaceous I(The "High Cretaceous")16.1 My
Santonian
85.8
2.3
Coniacian
89.3
3.5
Gallic
Turonian
93.5
4.2
Cenomanian
99.6
6.1
Early Cretaceous II(Aptian-Albian)25.4 My
Albian
112.0
12.4
Aptian
125.0
13.0
Early Cretaceous I("Neocomian")20.5 My
Barremian
130.0
5.0
Neocomian
Hauterivian
136.4
6.4
Valanginian
140.2
3.8
Berriasian
145.5
5.3
Jurassic
Late Jurassic: 15.7 My
Malm
Tithonian
150.8
5.3
i have used the Harland three-fold division of the Cretaceous into Neocomian, Gallic, and Senonian Epochs. As of this writing (040911) we are in the process of gradually converting to the ICS system, which recognizes only Early and Late Cretaceous epochs. Unfortunately, the ICS Cretaceous epochs are unreasonably long for our purposes, so we have taken the further step of dividing both of them into two.
Our "Neocomian" division is based largely on climatic considerations. This "Early Early Cretaceous" demi-epoch was a time of steadily rising seas and temperatures. According to one source, the ocean temperature increased an almost unbelievable 17 C° over the Early Cretaceous, and the bulk of this must increase must have occurred in the Neocomian division. The Aptian-Albian division continued the Neocomian trend, but at a slower rate. The Aptian-Albian is also the interval that produced the definitive Cretaceous dinosaur clades. These dinosaurs dominated the large herbivore guild in the Late Cretaceous: the ornithischian iguanodonts (including hadrosaurs), Ceratopsia (e.g. Triceratops), and various saurischian titanosaurs. In the oceans, a final radiation of pliosaurs also occurred at about this time.
The Early Late Cretaceous ("High Cretaceous") was marked by several critical events. The first was the widening Atlantic rift. The Atlantic Ocean: (a) had become wide enough to become a complete barrier to east-west dispersal over its entire length, except in the far north, and (b) was circulating meaningful amounts of ocean water north and south. The initial results seem somewhat paradoxical. On the one hand, the High Cretaceous experienced unprecedented uniformity of ocean temperatures from pole to pole, suggesting very good horizontal mixing of ocean waters. On the other hand, it is well known for sporadic deep ocean anoxia, which would indicate poor vertical mixing. It is tempting to speculate on the causes of this peculiar set of events. One strong line of evidence implicates methane and/or carbon dioxide outgassing. But most of this data comes from the Atlantic basin. In due course, we will have enough information from the Pacific to give us a better global perspective.
The second major event of the High Cretaceous was angiosperm dominance. Angiosperm plants had begun to spread at least as early as the middle Neocomian. However, during the High Cretaceous, angiosperms reached some critical mass or critical stage of development and became the dominant type of plant in most parts of the world. Finally, the long, gradual increase in sea levels which began in the Triassic reached its peak in the High Cretaceous. During the End-Cretaceous, sea levels began to retreat after 165 million years of advances. Miller et al. (2003) have recently reported that the peak and decline of sea levels in the Late Cretaceous is punctuated by a number of sudden, drastic, marine regressions. Apparently, the oceans retreated quite quickly, and, almost as quickly, returned to more or less their former depths. The pace of these changes appears to have been below the limit of geological resolution for their core samples, i.e. about <500Ky. Miller et al. state that their data are consistent only with the formation of short-lived, but rather extensive ice sheets in Antarctica. This conclusion is almost -- but not quite -- irreconcilable with what we know about Late Cretaceous climate. Miller's group coordinates data from a number of different regions in arriving at this result. While these sequences are diverse, they still cover only the Atlantic and Tethyan regions. Once again, we are badly in need of data from the Pacific Basin.
more to follow on cretaceous in join me in irvincalicut.blogspot.com
Period
Epoch (ICS, with added subdivision)
Harland Epoch
Age
ICS Base
ICS Duration
Paleogene
Paleocene: 9.7 My
Paleocene
Danian
65.5
3.8
Cretaceous80.0 My
Late Cretaceous II(End-Cretaceous)18.0 My
Senonian
Maastrichtian
70.6
5.1
Campanian
83.5
12.9
Late Cretaceous I(The "High Cretaceous")16.1 My
Santonian
85.8
2.3
Coniacian
89.3
3.5
Gallic
Turonian
93.5
4.2
Cenomanian
99.6
6.1
Early Cretaceous II(Aptian-Albian)25.4 My
Albian
112.0
12.4
Aptian
125.0
13.0
Early Cretaceous I("Neocomian")20.5 My
Barremian
130.0
5.0
Neocomian
Hauterivian
136.4
6.4
Valanginian
140.2
3.8
Berriasian
145.5
5.3
Jurassic
Late Jurassic: 15.7 My
Malm
Tithonian
150.8
5.3
i have used the Harland three-fold division of the Cretaceous into Neocomian, Gallic, and Senonian Epochs. As of this writing (040911) we are in the process of gradually converting to the ICS system, which recognizes only Early and Late Cretaceous epochs. Unfortunately, the ICS Cretaceous epochs are unreasonably long for our purposes, so we have taken the further step of dividing both of them into two.
Our "Neocomian" division is based largely on climatic considerations. This "Early Early Cretaceous" demi-epoch was a time of steadily rising seas and temperatures. According to one source, the ocean temperature increased an almost unbelievable 17 C° over the Early Cretaceous, and the bulk of this must increase must have occurred in the Neocomian division. The Aptian-Albian division continued the Neocomian trend, but at a slower rate. The Aptian-Albian is also the interval that produced the definitive Cretaceous dinosaur clades. These dinosaurs dominated the large herbivore guild in the Late Cretaceous: the ornithischian iguanodonts (including hadrosaurs), Ceratopsia (e.g. Triceratops), and various saurischian titanosaurs. In the oceans, a final radiation of pliosaurs also occurred at about this time.
The Early Late Cretaceous ("High Cretaceous") was marked by several critical events. The first was the widening Atlantic rift. The Atlantic Ocean: (a) had become wide enough to become a complete barrier to east-west dispersal over its entire length, except in the far north, and (b) was circulating meaningful amounts of ocean water north and south. The initial results seem somewhat paradoxical. On the one hand, the High Cretaceous experienced unprecedented uniformity of ocean temperatures from pole to pole, suggesting very good horizontal mixing of ocean waters. On the other hand, it is well known for sporadic deep ocean anoxia, which would indicate poor vertical mixing. It is tempting to speculate on the causes of this peculiar set of events. One strong line of evidence implicates methane and/or carbon dioxide outgassing. But most of this data comes from the Atlantic basin. In due course, we will have enough information from the Pacific to give us a better global perspective.
The second major event of the High Cretaceous was angiosperm dominance. Angiosperm plants had begun to spread at least as early as the middle Neocomian. However, during the High Cretaceous, angiosperms reached some critical mass or critical stage of development and became the dominant type of plant in most parts of the world. Finally, the long, gradual increase in sea levels which began in the Triassic reached its peak in the High Cretaceous. During the End-Cretaceous, sea levels began to retreat after 165 million years of advances. Miller et al. (2003) have recently reported that the peak and decline of sea levels in the Late Cretaceous is punctuated by a number of sudden, drastic, marine regressions. Apparently, the oceans retreated quite quickly, and, almost as quickly, returned to more or less their former depths. The pace of these changes appears to have been below the limit of geological resolution for their core samples, i.e. about <500Ky. Miller et al. state that their data are consistent only with the formation of short-lived, but rather extensive ice sheets in Antarctica. This conclusion is almost -- but not quite -- irreconcilable with what we know about Late Cretaceous climate. Miller's group coordinates data from a number of different regions in arriving at this result. While these sequences are diverse, they still cover only the Atlantic and Tethyan regions. Once again, we are badly in need of data from the Pacific Basin.
more to follow on cretaceous in join me in irvincalicut.blogspot.com
Monday, February 26, 2007
now guys lets move on to cretaceous period with me irvin
The Cretaceous Period - 1
The Cretaceous Period of the Mesozoic Era: 146 to 65.5 million years ago
Introduction
In 1822 the Belgian geologist D'Omalius d'Halloy gave the name Terrain Cretace, for the chalk and rock outcrops of the Paris Basin, and for similar deposits in Belgium and Holland and traceable also from England eastward into Sweden and Poland.
This term "Cretaceous" "chalk-bearing" (from Creta, the Latin word for chalk) later came to be used. The famous White Cliffs of Dover, are typical of this rock formation. Extensive chalk deposits were laid down in Europe and parts of North America during this period. The chalk itself is actually formed from the shells of countless micro-organisms.
William Smith had previously mapped four strata between the lower clay (= early Tertiary) and the "Portland Stone" (= late Jurassic), namely White Chalk, Brown or Grey Chalk, Greensand, and Micaceous Clay or brick earth (later referred to as Blue Marl or Gault). In 1822 Conybeare and Phillips arranged these in two groups, the Chalk and the earlier strata, a division that has remained to the present day. In 1841 Leymerie introduced the term Neocomian for the lower division. Senonian was coined by d'Orbigny in 1842 for the later Cretaceous. The name "Gallic" has also been used for times that do not fall conveniently into either of the above two categories.
The Cretaceous Period - 1
The Cretaceous Period of the Mesozoic Era: 146 to 65.5 million years ago
Introduction
In 1822 the Belgian geologist D'Omalius d'Halloy gave the name Terrain Cretace, for the chalk and rock outcrops of the Paris Basin, and for similar deposits in Belgium and Holland and traceable also from England eastward into Sweden and Poland.
This term "Cretaceous" "chalk-bearing" (from Creta, the Latin word for chalk) later came to be used. The famous White Cliffs of Dover, are typical of this rock formation. Extensive chalk deposits were laid down in Europe and parts of North America during this period. The chalk itself is actually formed from the shells of countless micro-organisms.
William Smith had previously mapped four strata between the lower clay (= early Tertiary) and the "Portland Stone" (= late Jurassic), namely White Chalk, Brown or Grey Chalk, Greensand, and Micaceous Clay or brick earth (later referred to as Blue Marl or Gault). In 1822 Conybeare and Phillips arranged these in two groups, the Chalk and the earlier strata, a division that has remained to the present day. In 1841 Leymerie introduced the term Neocomian for the lower division. Senonian was coined by d'Orbigny in 1842 for the later Cretaceous. The name "Gallic" has also been used for times that do not fall conveniently into either of the above two categories.
Thursday, February 22, 2007
now lets see what was in the oceans in the time of jurassic Period !IRVIN
Plankton
There must surely have been something special about the Jurassic oceans. Of the dozen or so types of planktonic organisms with a fossil record, at least four either first evolved or experienced massive radiation during Jurassic: coccolithophorids (evolved latest Triassic), diatoms (evolved Late Jurassic), dinoflagellates (radiated Jurassic), planktonic foraminifera (?evolved or radiated Jurassic), and ostracodes (radiated Jurassic). Most plankton groups experienced greater prominence yet in the Cretaceous. However, there seems to have been -- literally -- something in the water during the Jurassic. That "something" may simply have been lots of free calcium with which to build shells and tests; but, that would not explain the ostracodes and microcrustaceans that also seem to have found the Jurassic seas particularly congenial.
Nor were these the only marine groups who left Jurassic microfossils. The "modern" coralline group of the Rhodophyta (red algae) evolved in the Jurassic. They are called modern to distinguish them from the Paleozoic corallines. The current view is that the modern and Paleozoic corallines are unrelated. However, the otherwise unidentifiable Middle to Late Jurassic Iberopora may be a late member of a transitional taxon. Schlagintweit (2004). It would be useful to be more certain, since it has been suggested that the "something in the water" was the rhodophytes themselves -- or, rather, their chloroplasts. All of the new photosynthetic forms of the Jurassic were "red," with chloroplasts of the red algae type, with chlorophyll c, rather than the chlorophyll b of green plants and green algae (Chlorophyta). Falkowski et al. (2004). It is almost certain that these chloroplasts were "adopted" from red algae by some secondary symbiosis, rather than by descent from the Rhodophyta. Grzebyk et al. (2003).
Both of the last cited papers are from the Coastal Ocean Observatory Laboratory at Rutgers so (although it pains us to fall victim to so obvious a linguistic ploy) we'll refer to them as the COOL group. The COOL workers offer two reasons to explain why the ocean is "red." First, the Mesozoic rhodophyte chloroplast was a sturdy, self-reliant sort of plastid which had retained a much greater amount of its own DNA, and thus had greater genetic independence from its host. Consequently, by the Mesozoic, it was much easier for the red chloroplast to trade symbionts than it might have been for some debased, decadent green chloroplasts, which had surrendered most of its genetic control to its hosts. Second, the COOL group notes that red and green species are associated with different trace element requirements. The "red" elements are cadmium, cobalt and manganese, while the "green" elements are copper and iron. This leads the COOL group into a somewhat confused discussion of ocean anoxia and its effects on trace element availability. We suggest that they are correct about trace elements, but for the wrong reasons. Marine iron concentrations are largely dependent on continental weathering. Iron is high when the winds drop iron-bearing dust weathered from barren, arid inland areas. The rising seas and humid, equable conditions of the Mesozoic strongly reduced the availability of marine iron. It is not really necessary to invoke anything more complicated; however, we may also note that sulfides produced at the highly active Mesozoic mid-ocean ridges would also draw down dissolved iron as insoluble pyrite.
The Jurassic was also, in a small way, a good time for acritarchs. Acritarchs are just curiously shaped organic casings, without any particular phylogenetic identity. The Jurassic variety are probably some type of radiolarian-like protist and may have nothing at all to do with the Paleozoic acritarchs. For radiolarians of the more conventional type, the Jurassic was also favorable. The Jurassic radiation of radiolarians was largely a radiation of the Spumellaria in the latter half of the Jurassic. Pantanellium, shown in the image, is a rather typical spumellarian. There is some speculation that this Late Jurassic recovery from a long period of decline may have been due to the availability of planktonic foraminifera as a food source. However, this remains speculation. Most radiolarian work in the Mesozoic is limited to identifying taxa for stratigraphic purposes. Surprisingly little has been done on their paleoecology or evolution.
There must surely have been something special about the Jurassic oceans. Of the dozen or so types of planktonic organisms with a fossil record, at least four either first evolved or experienced massive radiation during Jurassic: coccolithophorids (evolved latest Triassic), diatoms (evolved Late Jurassic), dinoflagellates (radiated Jurassic), planktonic foraminifera (?evolved or radiated Jurassic), and ostracodes (radiated Jurassic). Most plankton groups experienced greater prominence yet in the Cretaceous. However, there seems to have been -- literally -- something in the water during the Jurassic. That "something" may simply have been lots of free calcium with which to build shells and tests; but, that would not explain the ostracodes and microcrustaceans that also seem to have found the Jurassic seas particularly congenial.
Nor were these the only marine groups who left Jurassic microfossils. The "modern" coralline group of the Rhodophyta (red algae) evolved in the Jurassic. They are called modern to distinguish them from the Paleozoic corallines. The current view is that the modern and Paleozoic corallines are unrelated. However, the otherwise unidentifiable Middle to Late Jurassic Iberopora may be a late member of a transitional taxon. Schlagintweit (2004). It would be useful to be more certain, since it has been suggested that the "something in the water" was the rhodophytes themselves -- or, rather, their chloroplasts. All of the new photosynthetic forms of the Jurassic were "red," with chloroplasts of the red algae type, with chlorophyll c, rather than the chlorophyll b of green plants and green algae (Chlorophyta). Falkowski et al. (2004). It is almost certain that these chloroplasts were "adopted" from red algae by some secondary symbiosis, rather than by descent from the Rhodophyta. Grzebyk et al. (2003).
Both of the last cited papers are from the Coastal Ocean Observatory Laboratory at Rutgers so (although it pains us to fall victim to so obvious a linguistic ploy) we'll refer to them as the COOL group. The COOL workers offer two reasons to explain why the ocean is "red." First, the Mesozoic rhodophyte chloroplast was a sturdy, self-reliant sort of plastid which had retained a much greater amount of its own DNA, and thus had greater genetic independence from its host. Consequently, by the Mesozoic, it was much easier for the red chloroplast to trade symbionts than it might have been for some debased, decadent green chloroplasts, which had surrendered most of its genetic control to its hosts. Second, the COOL group notes that red and green species are associated with different trace element requirements. The "red" elements are cadmium, cobalt and manganese, while the "green" elements are copper and iron. This leads the COOL group into a somewhat confused discussion of ocean anoxia and its effects on trace element availability. We suggest that they are correct about trace elements, but for the wrong reasons. Marine iron concentrations are largely dependent on continental weathering. Iron is high when the winds drop iron-bearing dust weathered from barren, arid inland areas. The rising seas and humid, equable conditions of the Mesozoic strongly reduced the availability of marine iron. It is not really necessary to invoke anything more complicated; however, we may also note that sulfides produced at the highly active Mesozoic mid-ocean ridges would also draw down dissolved iron as insoluble pyrite.
The Jurassic was also, in a small way, a good time for acritarchs. Acritarchs are just curiously shaped organic casings, without any particular phylogenetic identity. The Jurassic variety are probably some type of radiolarian-like protist and may have nothing at all to do with the Paleozoic acritarchs. For radiolarians of the more conventional type, the Jurassic was also favorable. The Jurassic radiation of radiolarians was largely a radiation of the Spumellaria in the latter half of the Jurassic. Pantanellium, shown in the image, is a rather typical spumellarian. There is some speculation that this Late Jurassic recovery from a long period of decline may have been due to the availability of planktonic foraminifera as a food source. However, this remains speculation. Most radiolarian work in the Mesozoic is limited to identifying taxa for stratigraphic purposes. Surprisingly little has been done on their paleoecology or evolution.
now lets see what was in the oceans in the time of jurassic Period !IRVIN
Plankton
There must surely have been something special about the Jurassic oceans. Of the dozen or so types of planktonic organisms with a fossil record, at least four either first evolved or experienced massive radiation during Jurassic: coccolithophorids (evolved latest Triassic), diatoms (evolved Late Jurassic), dinoflagellates (radiated Jurassic), planktonic foraminifera (?evolved or radiated Jurassic), and ostracodes (radiated Jurassic). Most plankton groups experienced greater prominence yet in the Cretaceous. However, there seems to have been -- literally -- something in the water during the Jurassic. That "something" may simply have been lots of free calcium with which to build shells and tests; but, that would not explain the ostracodes and microcrustaceans that also seem to have found the Jurassic seas particularly congenial.
Nor were these the only marine groups who left Jurassic microfossils. The "modern" coralline group of the Rhodophyta (red algae) evolved in the Jurassic. They are called modern to distinguish them from the Paleozoic corallines. The current view is that the modern and Paleozoic corallines are unrelated. However, the otherwise unidentifiable Middle to Late Jurassic Iberopora may be a late member of a transitional taxon. Schlagintweit (2004). It would be useful to be more certain, since it has been suggested that the "something in the water" was the rhodophytes themselves -- or, rather, their chloroplasts. All of the new photosynthetic forms of the Jurassic were "red," with chloroplasts of the red algae type, with chlorophyll c, rather than the chlorophyll b of green plants and green algae (Chlorophyta). Falkowski et al. (2004). It is almost certain that these chloroplasts were "adopted" from red algae by some secondary symbiosis, rather than by descent from the Rhodophyta. Grzebyk et al. (2003).
Both of the last cited papers are from the Coastal Ocean Observatory Laboratory at Rutgers so (although it pains us to fall victim to so obvious a linguistic ploy) we'll refer to them as the COOL group. The COOL workers offer two reasons to explain why the ocean is "red." First, the Mesozoic rhodophyte chloroplast was a sturdy, self-reliant sort of plastid which had retained a much greater amount of its own DNA, and thus had greater genetic independence from its host. Consequently, by the Mesozoic, it was much easier for the red chloroplast to trade symbionts than it might have been for some debased, decadent green chloroplasts, which had surrendered most of its genetic control to its hosts. Second, the COOL group notes that red and green species are associated with different trace element requirements. The "red" elements are cadmium, cobalt and manganese, while the "green" elements are copper and iron. This leads the COOL group into a somewhat confused discussion of ocean anoxia and its effects on trace element availability. We suggest that they are correct about trace elements, but for the wrong reasons. Marine iron concentrations are largely dependent on continental weathering. Iron is high when the winds drop iron-bearing dust weathered from barren, arid inland areas. The rising seas and humid, equable conditions of the Mesozoic strongly reduced the availability of marine iron. It is not really necessary to invoke anything more complicated; however, we may also note that sulfides produced at the highly active Mesozoic mid-ocean ridges would also draw down dissolved iron as insoluble pyrite.
The Jurassic was also, in a small way, a good time for acritarchs. Acritarchs are just curiously shaped organic casings, without any particular phylogenetic identity. The Jurassic variety are probably some type of radiolarian-like protist and may have nothing at all to do with the Paleozoic acritarchs. For radiolarians of the more conventional type, the Jurassic was also favorable. The Jurassic radiation of radiolarians was largely a radiation of the Spumellaria in the latter half of the Jurassic. Pantanellium, shown in the image, is a rather typical spumellarian. There is some speculation that this Late Jurassic recovery from a long period of decline may have been due to the availability of planktonic foraminifera as a food source. However, this remains speculation. Most radiolarian work in the Mesozoic is limited to identifying taxa for stratigraphic purposes. Surprisingly little has been done on their paleoecology or evolution.
There must surely have been something special about the Jurassic oceans. Of the dozen or so types of planktonic organisms with a fossil record, at least four either first evolved or experienced massive radiation during Jurassic: coccolithophorids (evolved latest Triassic), diatoms (evolved Late Jurassic), dinoflagellates (radiated Jurassic), planktonic foraminifera (?evolved or radiated Jurassic), and ostracodes (radiated Jurassic). Most plankton groups experienced greater prominence yet in the Cretaceous. However, there seems to have been -- literally -- something in the water during the Jurassic. That "something" may simply have been lots of free calcium with which to build shells and tests; but, that would not explain the ostracodes and microcrustaceans that also seem to have found the Jurassic seas particularly congenial.
Nor were these the only marine groups who left Jurassic microfossils. The "modern" coralline group of the Rhodophyta (red algae) evolved in the Jurassic. They are called modern to distinguish them from the Paleozoic corallines. The current view is that the modern and Paleozoic corallines are unrelated. However, the otherwise unidentifiable Middle to Late Jurassic Iberopora may be a late member of a transitional taxon. Schlagintweit (2004). It would be useful to be more certain, since it has been suggested that the "something in the water" was the rhodophytes themselves -- or, rather, their chloroplasts. All of the new photosynthetic forms of the Jurassic were "red," with chloroplasts of the red algae type, with chlorophyll c, rather than the chlorophyll b of green plants and green algae (Chlorophyta). Falkowski et al. (2004). It is almost certain that these chloroplasts were "adopted" from red algae by some secondary symbiosis, rather than by descent from the Rhodophyta. Grzebyk et al. (2003).
Both of the last cited papers are from the Coastal Ocean Observatory Laboratory at Rutgers so (although it pains us to fall victim to so obvious a linguistic ploy) we'll refer to them as the COOL group. The COOL workers offer two reasons to explain why the ocean is "red." First, the Mesozoic rhodophyte chloroplast was a sturdy, self-reliant sort of plastid which had retained a much greater amount of its own DNA, and thus had greater genetic independence from its host. Consequently, by the Mesozoic, it was much easier for the red chloroplast to trade symbionts than it might have been for some debased, decadent green chloroplasts, which had surrendered most of its genetic control to its hosts. Second, the COOL group notes that red and green species are associated with different trace element requirements. The "red" elements are cadmium, cobalt and manganese, while the "green" elements are copper and iron. This leads the COOL group into a somewhat confused discussion of ocean anoxia and its effects on trace element availability. We suggest that they are correct about trace elements, but for the wrong reasons. Marine iron concentrations are largely dependent on continental weathering. Iron is high when the winds drop iron-bearing dust weathered from barren, arid inland areas. The rising seas and humid, equable conditions of the Mesozoic strongly reduced the availability of marine iron. It is not really necessary to invoke anything more complicated; however, we may also note that sulfides produced at the highly active Mesozoic mid-ocean ridges would also draw down dissolved iron as insoluble pyrite.
The Jurassic was also, in a small way, a good time for acritarchs. Acritarchs are just curiously shaped organic casings, without any particular phylogenetic identity. The Jurassic variety are probably some type of radiolarian-like protist and may have nothing at all to do with the Paleozoic acritarchs. For radiolarians of the more conventional type, the Jurassic was also favorable. The Jurassic radiation of radiolarians was largely a radiation of the Spumellaria in the latter half of the Jurassic. Pantanellium, shown in the image, is a rather typical spumellarian. There is some speculation that this Late Jurassic recovery from a long period of decline may have been due to the availability of planktonic foraminifera as a food source. However, this remains speculation. Most radiolarian work in the Mesozoic is limited to identifying taxa for stratigraphic purposes. Surprisingly little has been done on their paleoecology or evolution.
Tuesday, February 20, 2007
now lets see the how the jurassic life worked in that very best Jurassic period with me irvin
Jurassic Life
On land gymnosperm plants were well represented. The superficially palm-like Cycadophyta (Cycads) were so abundant and diverse that the Jurassic period could well be called "the Age of Cycads" Some cycads were tall palm-like trees with rough branches marked by leaf scars, and pinnate (fern-like) leaf fronds. Other, unrelated forms, the equatorial flowering Bennettitales, were the most important group of shrubby trees, with short and stubby with squat bulbous trunks from the top of which the fronds grew.
Conifers continued to be the most diverse large trees, and included representatives of the extant (still living) families Araucariaceae, Cephalotaxaceae, Pinaceae, Podocarpaceae, Taxaceae, and Taxodiaceae, along with the extinct equatorial Cheirolepidiaceae. Ginkgos were important, particularly in mid to high northern latitudes. Dicksoniaceous tree ferns and Caytoniaceous seed ferns were relatively successful plants in the shrubby tree size range. The Cyatheaceae tree ferns may have (and still do) reach(ed) heights of 20 meters. Osmundaceous, matoniaceous, and dipteridaceous ferns were probably the dominant undergrowth and small plants. Lycopods remained relatively insignificant and sphenopsids were represented by the small (and still surviving "living fossil") Equisetum or "horsetail"
In the seas there was a great diversity of invertebrates. Sponges, corals, bryozoa, gastropods, bivalves, and ammonoid (left) and belemnite cephalopods all flourished, the latter two groups becoming the dominant nektonic invertebrates for the rest of the Mesozoic.
Brachiopods and Crinoids continued, but with nowhere like their Paleozoic glory.
Freshwater bivalves (clams), snails, and branchiopod Crustacea were common. On land, numerous groups of herbivorous insects were present, including the orders Orthoptera, Hemoptera (among which were the superfamilies Cicadelloidea and Fulgoroidea (leafhoppers), Psylloidea (plant hoppers), Pentatomoidea (shield bugs), and Cimicoidea (plant bugs)), Thysanoptera (thrips), Coleoptera (beetles, including most extant groups) and primitive Hymenoptera (sawflies). Pulmonate snails, millipedes, scorpions, spiders and mites were certainly present, but are not known from fossils.
As for the vertebrates, modern shark groups begin to appear. Bony fish are still mostly the intermediate heavy scaled holostean type, although the first teleosts appear early in the period. The gigantic Leedsichthys, a huge, scaleless filter feeder, reached 10 or even 30 meters in length, and filled the same ecological role as modern baleen whales.
On land, a few basal tetrapods struggled on, but most amphibians were of essential modern types (frogs and newts), although the most primitive representatives of those orders.
Sphenodont lepidosaurs took the same ecological role as lizards do today. Crocodiles were abundant and diverse, and included marine, semi-aquatic and even a few small lizard-like terrestrial forms.
In the oceans new types of ichthyosaurs replaced their Triassic predecessors. The cousins of the Triassic nothosaurs, the long-necked plesiosauroids and short-necked pliosauroids, were also common. All these marine reptiles, filled similar ecological roles to cetaceans of the Cenozoic. In the air were various types of pterosaur, these were mostly small to medium-sized forms, all were endothermic with a covering of fur.
Dinosaurs were diverse and abundant, and their was a rich megafauna of huge sauropods (including a number of families - Euhelopidae, Cetiosauridae, Brachiosaurus, Camarasaurs, Diplodocidae, etc), reaching many tons in weight, and the more modestly sized Scelidosauridae, Stegosauridae, and the camptosaurid iguanodonts. The browsing pressure these great beasts exerted on the vegetation must have been tremendous, although there is continuing argument whether the dinosaurs were ectotherms, endotherms, homeotherms, gigantotherms, or (as seems most likely) some combination of all of the preceding. Obviously, the higher their metabolism the greater the selection pressure they would have exerted on the contemporary vegetation. Along with the giant herbivores there were also the small fleet-footed "fabrosaurs", scutellosaurs, and hypsilophodontids, the "gazelles" of the dinosaurian world. These plant eaters were kept in check by a variety of carnivorous (theropod) dinosaurs, including small lightly built coelophysids, compsognathids, and ornitholestids, and larger (from several hundred kilos to several tons in weight) dilophosaurids, Ceratosauria, Torvosauroidea, and Allosauridae. Some of the smaller carnivores developed feathers and took to the air, these were the proto-bird Archaeornithes.A few tritylodontid therapsids straggled on, but it was a diverse assemblage of Mesozoic Mammals that played an important part of the microvertebrate fauna, filling the same ecological role as Insectivora and rodents do today.
please find the answers to your query at the links provided on complicated or dino names !
Jurassic Life
On land gymnosperm plants were well represented. The superficially palm-like Cycadophyta (Cycads) were so abundant and diverse that the Jurassic period could well be called "the Age of Cycads" Some cycads were tall palm-like trees with rough branches marked by leaf scars, and pinnate (fern-like) leaf fronds. Other, unrelated forms, the equatorial flowering Bennettitales, were the most important group of shrubby trees, with short and stubby with squat bulbous trunks from the top of which the fronds grew.
Conifers continued to be the most diverse large trees, and included representatives of the extant (still living) families Araucariaceae, Cephalotaxaceae, Pinaceae, Podocarpaceae, Taxaceae, and Taxodiaceae, along with the extinct equatorial Cheirolepidiaceae. Ginkgos were important, particularly in mid to high northern latitudes. Dicksoniaceous tree ferns and Caytoniaceous seed ferns were relatively successful plants in the shrubby tree size range. The Cyatheaceae tree ferns may have (and still do) reach(ed) heights of 20 meters. Osmundaceous, matoniaceous, and dipteridaceous ferns were probably the dominant undergrowth and small plants. Lycopods remained relatively insignificant and sphenopsids were represented by the small (and still surviving "living fossil") Equisetum or "horsetail"
In the seas there was a great diversity of invertebrates. Sponges, corals, bryozoa, gastropods, bivalves, and ammonoid (left) and belemnite cephalopods all flourished, the latter two groups becoming the dominant nektonic invertebrates for the rest of the Mesozoic.
Brachiopods and Crinoids continued, but with nowhere like their Paleozoic glory.
Freshwater bivalves (clams), snails, and branchiopod Crustacea were common. On land, numerous groups of herbivorous insects were present, including the orders Orthoptera, Hemoptera (among which were the superfamilies Cicadelloidea and Fulgoroidea (leafhoppers), Psylloidea (plant hoppers), Pentatomoidea (shield bugs), and Cimicoidea (plant bugs)), Thysanoptera (thrips), Coleoptera (beetles, including most extant groups) and primitive Hymenoptera (sawflies). Pulmonate snails, millipedes, scorpions, spiders and mites were certainly present, but are not known from fossils.
As for the vertebrates, modern shark groups begin to appear. Bony fish are still mostly the intermediate heavy scaled holostean type, although the first teleosts appear early in the period. The gigantic Leedsichthys, a huge, scaleless filter feeder, reached 10 or even 30 meters in length, and filled the same ecological role as modern baleen whales.
On land, a few basal tetrapods struggled on, but most amphibians were of essential modern types (frogs and newts), although the most primitive representatives of those orders.
Sphenodont lepidosaurs took the same ecological role as lizards do today. Crocodiles were abundant and diverse, and included marine, semi-aquatic and even a few small lizard-like terrestrial forms.
In the oceans new types of ichthyosaurs replaced their Triassic predecessors. The cousins of the Triassic nothosaurs, the long-necked plesiosauroids and short-necked pliosauroids, were also common. All these marine reptiles, filled similar ecological roles to cetaceans of the Cenozoic. In the air were various types of pterosaur, these were mostly small to medium-sized forms, all were endothermic with a covering of fur.
Dinosaurs were diverse and abundant, and their was a rich megafauna of huge sauropods (including a number of families - Euhelopidae, Cetiosauridae, Brachiosaurus, Camarasaurs, Diplodocidae, etc), reaching many tons in weight, and the more modestly sized Scelidosauridae, Stegosauridae, and the camptosaurid iguanodonts. The browsing pressure these great beasts exerted on the vegetation must have been tremendous, although there is continuing argument whether the dinosaurs were ectotherms, endotherms, homeotherms, gigantotherms, or (as seems most likely) some combination of all of the preceding. Obviously, the higher their metabolism the greater the selection pressure they would have exerted on the contemporary vegetation. Along with the giant herbivores there were also the small fleet-footed "fabrosaurs", scutellosaurs, and hypsilophodontids, the "gazelles" of the dinosaurian world. These plant eaters were kept in check by a variety of carnivorous (theropod) dinosaurs, including small lightly built coelophysids, compsognathids, and ornitholestids, and larger (from several hundred kilos to several tons in weight) dilophosaurids, Ceratosauria, Torvosauroidea, and Allosauridae. Some of the smaller carnivores developed feathers and took to the air, these were the proto-bird Archaeornithes.A few tritylodontid therapsids straggled on, but it was a diverse assemblage of Mesozoic Mammals that played an important part of the microvertebrate fauna, filling the same ecological role as Insectivora and rodents do today.
please find the answers to your query at the links provided on complicated or dino names !
Wednesday, February 14, 2007
today we will go through the time chart of JURASSIC Period Ok !
Stratigraphy
Period
Epoch (sub-period)
Age
When began
Duration
Cretaceous
Early Cretaceous
Berriasian
146
6
Jurassic54 My
Late Jurassic(Malm) 15 My
Tithonian
151
5
Kimmeridgian
156
5
Oxfordian
161
5
Middle Jurassic (Dogger) 15 My
Callovian
165
4
Bathonian
168
3
Bajocian
172
4
Aalenian
176
4
Early Jurassic(Lias) 24 My
Toarcian
183
7
Pliensbachian
190
7
Sinemurian
197
7
Hettangian
200
3
Triassic
Late Triassic
Rhaetian
204
4
sorry guys this chart is strictly for professionals but any one can grab the basics if you just figure out this !
Stratigraphy
Period
Epoch (sub-period)
Age
When began
Duration
Cretaceous
Early Cretaceous
Berriasian
146
6
Jurassic54 My
Late Jurassic(Malm) 15 My
Tithonian
151
5
Kimmeridgian
156
5
Oxfordian
161
5
Middle Jurassic (Dogger) 15 My
Callovian
165
4
Bathonian
168
3
Bajocian
172
4
Aalenian
176
4
Early Jurassic(Lias) 24 My
Toarcian
183
7
Pliensbachian
190
7
Sinemurian
197
7
Hettangian
200
3
Triassic
Late Triassic
Rhaetian
204
4
sorry guys this chart is strictly for professionals but any one can grab the basics if you just figure out this !
Monday, February 12, 2007
lets further explore the features of Jurassic period with me IRVIN.
Jurassic Geography
The Jurassic saw disintegration of Pangea that began in the Triassic continuing apace. The supercontinent begins to rotate, but the different components of the huge mass rotated at different rates and then in different directions, forming rift valleys. One of these opened the southern part of the North Atlantic Ocean and continued westward into the Gulf of Mexico. This was North America drifting westward, opening the Gulf of Mexico, forming the central Atlantic. As Greenland-North America separate from Europe-Africa and slide over the Pacific Ocean floor, mountain-building events are triggered that created the North American Cordillera (the Rocky Mountains and the Sierra Nevada). A huge arc was built on western North America and the Nevadan orogeny begins. Cimmeria begins its collision with Laurasia to form the Cimmerian orogeny.
In Gondwana the initial narrow split between South America and Africa that began during the Triassic widened into a configuration resembling the present-day Red Sea. New sea floor formed along the nascent South Atlantic. This lengthened into a long, narrow seaway between South America and Africa. The Western side South America was subducted by an opposing oceanic plate. A great rift separates Antarctica from the southern ends of South America and Africa, developing an arm that extends eastward from South Africa along what is presently the eastern side of India, which began drifting northward.. Volcanoes located along these rifts erupted and issued huge amounts of basaltic lavas. The separated segments of Gondwanaland move slowly northward, turning gently counter-clockwise. Early rifting along the Australia-Antarctica join provided moist forested conditions that became coal deposits.
During the Jurassic the extent of the oceans was far more widespread then they had been in the Triassic. The Jurassic sea level rose and flooded large portions of the continents. Shallow epi-continental seas spilled out of the Tethys and Proto-Atlantic and spread across Europe, leaving a rich sedimentary record of limestone with fine clastics adjacent to the highlands. These warm shallow seas were home to a rich diversity of life. The spreading ocean crawled across Russia and into what is now the Arctic Sea before retreating at the end of the period. Meanwhile much of central North America was flooded by wide sea way that at its height extended into central Utah. This continent-wide embayment has been dubbed the Sundance Sea, and was fringed by strips of continental land on three sides.
there is lot more to come under jurassic period just wait and watch ! please feel free to use the links in the matter for more information.
Jurassic Geography
The Jurassic saw disintegration of Pangea that began in the Triassic continuing apace. The supercontinent begins to rotate, but the different components of the huge mass rotated at different rates and then in different directions, forming rift valleys. One of these opened the southern part of the North Atlantic Ocean and continued westward into the Gulf of Mexico. This was North America drifting westward, opening the Gulf of Mexico, forming the central Atlantic. As Greenland-North America separate from Europe-Africa and slide over the Pacific Ocean floor, mountain-building events are triggered that created the North American Cordillera (the Rocky Mountains and the Sierra Nevada). A huge arc was built on western North America and the Nevadan orogeny begins. Cimmeria begins its collision with Laurasia to form the Cimmerian orogeny.
In Gondwana the initial narrow split between South America and Africa that began during the Triassic widened into a configuration resembling the present-day Red Sea. New sea floor formed along the nascent South Atlantic. This lengthened into a long, narrow seaway between South America and Africa. The Western side South America was subducted by an opposing oceanic plate. A great rift separates Antarctica from the southern ends of South America and Africa, developing an arm that extends eastward from South Africa along what is presently the eastern side of India, which began drifting northward.. Volcanoes located along these rifts erupted and issued huge amounts of basaltic lavas. The separated segments of Gondwanaland move slowly northward, turning gently counter-clockwise. Early rifting along the Australia-Antarctica join provided moist forested conditions that became coal deposits.
During the Jurassic the extent of the oceans was far more widespread then they had been in the Triassic. The Jurassic sea level rose and flooded large portions of the continents. Shallow epi-continental seas spilled out of the Tethys and Proto-Atlantic and spread across Europe, leaving a rich sedimentary record of limestone with fine clastics adjacent to the highlands. These warm shallow seas were home to a rich diversity of life. The spreading ocean crawled across Russia and into what is now the Arctic Sea before retreating at the end of the period. Meanwhile much of central North America was flooded by wide sea way that at its height extended into central Utah. This continent-wide embayment has been dubbed the Sundance Sea, and was fringed by strips of continental land on three sides.
there is lot more to come under jurassic period just wait and watch ! please feel free to use the links in the matter for more information.
Saturday, February 10, 2007
today's blog is about the jurassic period !
The Jurassic
The Jurassic Period of the Mesozoic Era: 200 to 146 million years ago.
Introduction
The second of the three divisions that make up the Mesozoic era, the Jurassic period saw warm tropical greenhouse conditions world-wide, shallow continental seas, the break-up of Pangea, cosmopolitan flora and fauna, and the triumph of the majestic dinosaurs and the great sea reptiles.
The name Jurassic comes from the Jura Mountains on the border of France and Switzerland (actually an extension of the Alps into eastern France), where rocks of this age were first studied. In 1795 Alexander von Humbolt described massive limestone formations of the Jura Mountains in Switzerland as the Calcaire de Jura, or Jura-Kalkstein ("Jura Limestone"), which he wrongly believed were older than the (Triassic) Muschelkalk. Between 1796 and 1815 William Smith published geological maps featuring strata that were referred to by William Buckland in 1818 as the Oolite Formation or Oolitic Series. These were divided into Lower, Middle and Upper Oolites. In 1822 Conybeare and Phillips named the underlying strata as the Lias. From this Alexander Brongniart used the term Terrains Jurassiques, although only for the "Lower Oolite" The names Lias and Oolites continued to be used in Britain until quite recently.
In 1839 Leopold von Buch formally named the rocks described by von Humbolt as the Jurassic System, from whence the term has come into general use.
The immense wealth of fossils in Jurassic sediments of Britain (especially ammonites) meant that biostratigraphic zonation was further advanced for Jurassic sediments than for other periods. The terms used to divide the Jurassic Period into early, middle and late - Lias, Dogger, and Malm, are ones that originally referred only to English sediments.
The fact that the remains of many dinosaur and sea reptile remains have been found from the early nineteenth century on contributed to the Victorian imagination regarding "antediluvian monsters."Much more recently, the word Jurassic has become a household word with the success of Speilberg's rather absurd movie about genetically resurrected dinosaurs, Jurassic Park, based on a disappointing novel by Michael Crichton of the same name (actually the novel starts out quite well, but quickly slides into fantasy). Ironically most of dinosaurs featured in Jurassic Park actually lived during the following, Cretaceous, period. But then Cretaceous Park just doesn't have the same ring now, does it.
The Jurassic
The Jurassic Period of the Mesozoic Era: 200 to 146 million years ago.
Introduction
The second of the three divisions that make up the Mesozoic era, the Jurassic period saw warm tropical greenhouse conditions world-wide, shallow continental seas, the break-up of Pangea, cosmopolitan flora and fauna, and the triumph of the majestic dinosaurs and the great sea reptiles.
The name Jurassic comes from the Jura Mountains on the border of France and Switzerland (actually an extension of the Alps into eastern France), where rocks of this age were first studied. In 1795 Alexander von Humbolt described massive limestone formations of the Jura Mountains in Switzerland as the Calcaire de Jura, or Jura-Kalkstein ("Jura Limestone"), which he wrongly believed were older than the (Triassic) Muschelkalk. Between 1796 and 1815 William Smith published geological maps featuring strata that were referred to by William Buckland in 1818 as the Oolite Formation or Oolitic Series. These were divided into Lower, Middle and Upper Oolites. In 1822 Conybeare and Phillips named the underlying strata as the Lias. From this Alexander Brongniart used the term Terrains Jurassiques, although only for the "Lower Oolite" The names Lias and Oolites continued to be used in Britain until quite recently.
In 1839 Leopold von Buch formally named the rocks described by von Humbolt as the Jurassic System, from whence the term has come into general use.
The immense wealth of fossils in Jurassic sediments of Britain (especially ammonites) meant that biostratigraphic zonation was further advanced for Jurassic sediments than for other periods. The terms used to divide the Jurassic Period into early, middle and late - Lias, Dogger, and Malm, are ones that originally referred only to English sediments.
The fact that the remains of many dinosaur and sea reptile remains have been found from the early nineteenth century on contributed to the Victorian imagination regarding "antediluvian monsters."Much more recently, the word Jurassic has become a household word with the success of Speilberg's rather absurd movie about genetically resurrected dinosaurs, Jurassic Park, based on a disappointing novel by Michael Crichton of the same name (actually the novel starts out quite well, but quickly slides into fantasy). Ironically most of dinosaurs featured in Jurassic Park actually lived during the following, Cretaceous, period. But then Cretaceous Park just doesn't have the same ring now, does it.
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