By April 2005, the surface of Lake Powell, a human-made lake in Utah and Arizona, had fallen 145 feet below its highest level. This revealed many traces of ancient life that had not been observed since this area had been covered with water. Among these traces, discovered in sandstone bedrock, were many dinosaur tracks, ranging in age between 170 and 200 million years old.

What is the correct sequence of the events listed above that led to the formation and exposure of the dinosaur tracks in the surface bedrock along the shoreline of Lake Powell?

A 65.5-million-year-old impact crater in Mexico provides evidence for the cause of the

Layers of volcanic ash often serve as useful geologic time markers because ash layers usually

When do scientists think these continents were joined together?

What is a possible age of igneous rock E?

Which letter best indicates when trilobites became extinct?

Present-day evidence of the existence of the inland sea during the Pennsylvanian Period is best provided by

What is the total number of major glacial periods that have occurred in North America in the last 200,000 years?

A very large, circular, impact crater under the coast of Mexico is believed to be approximately 65 million years old. This impact event is inferred to be related to the

The sequence of rock layers in the cross section provides evidence that the Muave formation is

Volcanic ash deposits found in the geologic record are most useful in correlating the age of rock layers if the volcanic ash was distributed over a

Which column best represents the relative lengths of time of the major intervals of geologic history?

What is the geologic age of layer B?

According to the graph, the rate of uplifting was greater than the rate of erosion during which geologic time period?

Which graph shows the relative duration of geologic time for the Precambrian, Paleozoic, Mesozoic, and Cenozoic time intervals?

Which pie graph best represents the percentage of total time for the four major divisions of geologic time?

During which geologic era did life first appear on land?

Which number best represents when humans are inferred to have rst appeared on Earth?

What type of event usually marks the end of an era?

Each era is divided into

The disappearance of a species is known as...

Based on the law of superposition, where would the oldest rocks be found?

The Earth is estimated to be _____ years old.

Past environments can be determined using

Which era does the following characteristic fall into?

SMALL MAMMALS

Which era does the following characteristic fall into?

AMPHIBIANS

Which era does the following characteristic fall into?

LARGE MAMMALS

Which era does the following characteristic fall into?

DINOSAURS

Which era does the following characteristic fall into?

WARM, DRY TEMPERATURES

Which era does the following characteristic fall into?

THE ICE AGE

Which era does the following characteristic fall into?

FIRST PLANTS

Which era does the following characteristic fall into?

THE MIDDLE ERA

Which era does the following characteristic fall into?

FLOWERS

Which era does the following characteristic fall into?

HUMANS

Which era does the following characteristic fall into?

FIRST REPTILES

Which era does the following characteristic fall into?

THE ERA WE ARE CURRENTLY IN

Which era does the following characteristic fall into?

PANGAEA FORMED

Which era does the following characteristic fall into?

INSECTS

Which era does the following characteristic fall into?

THE OLDEST

Which era does the following characteristic fall into?

PANGAEA SPLITS APART

Which era does the following characteristic fall into?

MONKEYS/PRIMATES

Which era does the following characteristic fall into?

FISH

Which era does the following characteristic fall into?

MARINE LIFE MOVES TO LAND

Which type of fossil is found in the least recently formed sedimentary rock layer?

Human beings evolved during the cenozoic era