Alleghanian Mountains
About 320 MYA, Africa collided with PNA, which formed the Alleghanian Mountains. We know that the Alleghanian Orogeny happened because the Alleghanian Orogeny formed the Appalachian Mountains, and the remains of the Appalachian Mountains are still here today. 260 MYA, when the Alleghanian Mountains started eroding, the Appalachian Mountains eroded, but not completely, so the parts that did not erode are the parts we see today. During this time, the Iapetus Ocean was narrowing and subducting, and it finally disappeared. All continents came together to form a supercontinent, Pangea, during this time. At this time, North America is tilted upside down, and on the equator.
About 230 MYA, Pangea started to split up into separate continents, a process
known as rifting. The Connecticut Rift Valley is an area where North America could have potentially split away from Africa, which would form the Atlantic Ocean. But the basin where the Atlantic Ocean could have been failed, and the Atlantic Ocean formed in a different place. When the Connecticut Rift Valley was rifting, a lot of coarse stream sediments like mudstone and lava went into the valley. The tilted beds, which are the Longmeadow Formation, at the Rift Valley is made out of mostly sandstone, but some contain shale. They formed when sandy muds got deposited in water. A lot of layers of tilted beds contain ripple marks, mud cracks, raindrop impressions, and animal tracks which indicate that the water they were deposited in was shallow, and frequently dry and exposed to the sun. The tilted beds are colored tan, gray, brown, and are well sorted, fine grained, and arranged, with layers. During the Jurassic Period, 194 MYA, the Holyoke Basalts formed. The Holyoke Basalts were basalt that formed when basalt oozed about of faults. The Holyoke Range, which is 600 feet of flows, formed a ridge that stretches for a long distance, 50 miles. The basalt was radioactive minerals. The basalt is a gray pillow shaped, well sorted, randomly arranged, medium grained rock. The Holyoke Basalts can be found near the Connecticut River in Massachusetts. We have proof that this rock formed, because basalt is an igneous rock. Igneous rock forms from volcanic action, and the rifting action during that time indicates that there was volcanic action during that time, which formed this rock. The ripple marks at the Connecticut River Valley indicate that back then during the dinosaurs, the land was a muddy, swampy lake shore. The fossilized wood by the Connecticut River indicate that there was plant life near the river, during the time of the dinosaurs.The dinosaur footprints indicate to us that there was three dinosaur species living by the rift valley, since there were three sizes of footprints, small, medium, and large. Paleontologists have concluded with the footprints that dinosaurs moved in groups back then. The footprints also tell us that the dinosaurs were hunting by the river, and that they were moving away from the river, towards what is now the cement wall. The footprints in the tilted beds tell us that the dinosaurs walked on the tilted beds. When the rifting was going on, the Atlantic Ocean was opening up.
About 230 MYA, Pangea started to split up into separate continents, a process
known as rifting. The Connecticut Rift Valley is an area where North America could have potentially split away from Africa, which would form the Atlantic Ocean. But the basin where the Atlantic Ocean could have been failed, and the Atlantic Ocean formed in a different place. When the Connecticut Rift Valley was rifting, a lot of coarse stream sediments like mudstone and lava went into the valley. The tilted beds, which are the Longmeadow Formation, at the Rift Valley is made out of mostly sandstone, but some contain shale. They formed when sandy muds got deposited in water. A lot of layers of tilted beds contain ripple marks, mud cracks, raindrop impressions, and animal tracks which indicate that the water they were deposited in was shallow, and frequently dry and exposed to the sun. The tilted beds are colored tan, gray, brown, and are well sorted, fine grained, and arranged, with layers. During the Jurassic Period, 194 MYA, the Holyoke Basalts formed. The Holyoke Basalts were basalt that formed when basalt oozed about of faults. The Holyoke Range, which is 600 feet of flows, formed a ridge that stretches for a long distance, 50 miles. The basalt was radioactive minerals. The basalt is a gray pillow shaped, well sorted, randomly arranged, medium grained rock. The Holyoke Basalts can be found near the Connecticut River in Massachusetts. We have proof that this rock formed, because basalt is an igneous rock. Igneous rock forms from volcanic action, and the rifting action during that time indicates that there was volcanic action during that time, which formed this rock. The ripple marks at the Connecticut River Valley indicate that back then during the dinosaurs, the land was a muddy, swampy lake shore. The fossilized wood by the Connecticut River indicate that there was plant life near the river, during the time of the dinosaurs.The dinosaur footprints indicate to us that there was three dinosaur species living by the rift valley, since there were three sizes of footprints, small, medium, and large. Paleontologists have concluded with the footprints that dinosaurs moved in groups back then. The footprints also tell us that the dinosaurs were hunting by the river, and that they were moving away from the river, towards what is now the cement wall. The footprints in the tilted beds tell us that the dinosaurs walked on the tilted beds. When the rifting was going on, the Atlantic Ocean was opening up.