Jason Reed, a doctoral student in geological sciences at Virginia Tech, has determined that impervious cementing minerals deposited millions of years ago surround porous compartments in thick sandstone now more than 1,000 feet underground. Water, gas, or petroleum can be trapped within the porous compartments.

Reed will present his research at the 50th annual meeting of the Southeastern Section of the Geological Society of America (GSA) on April 5-6 in Raleigh, N.C.

Reed, who is from Parkersburg, W.Va., is studying core drilled by the U.S. Geological Survey and the West Virginia Geological and Economic Survey collected from coal fields near Beckley, WV He explains that, approximately 300 million years ago — during the Carboniferous period, loose sediment built up in ancient rivers followed by tidal environments during sea level rise, until the deposit was many feet thick. The material compacted into sandstone — a porous rock. In the process of being buried thousands of feet beneath the surface of the earth, the sandstone was cemented by various agents.

“We are looking at a particular kind of cementing agent — carbonate minerals, which we found isolated within distinctive zones that may extend laterally for many kilometers,” says Reed. He reports finding iron-rich and iron-magnesium-calcium carbonates. “The iron-rich carbonates appear to have formed early in the burial history. Later, as the sandstone was buried more deeply, higher concentrations of iron as well as magnesium and calcium were introduced into the system.” The element abundance and distribution in these carbonate cements reflect different formation conditions. The composition of the early iron-rich samples indicate that marine fluids influenced their formation during sea level rise. The cements that formed during deeper burial were likely affected by chemical reactions involving clay minerals and organic matter located in surrounding shale.

The sandstones involved in this study have up to 10 percent open space. The cementing minerals fill in the openings to form horizontal barriers to the flow of liquid or gas, leaving 20 to 50 meters (60 to 150 feet) of uncemented sandstone that may contain liquids or gas. “Such sub-surface compartments can persist for many square miles,” says Reed.

“Knowledge of compartmentalized sandstone is important to petroleum, natural gas, or ground water exploration,” says Reed. “If we understand the geometry of the compartments, we have an opportunity to predict fluid migration into and out of reservoirs. If we can discover something about the process, perhaps we can apply it on a global scale.”

The sandstone layer Reed is studying is now 1,100 feet deep. He is also trying to determine the original depth before erosion. “It would be deeper in northwest West Virginia, for instance,” he says.

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Scientists who analyze data from the Lunar Laser Ranging Experiment have reported some watershed results from these long-term experiments, begun 25 years ago when the Apollo 11 astronauts deployed a reflector array in the Sea of Tranquility. “Using the Lunar Laser Ranging Experiment, we have been able to improve, by orders of magnitude, measurements of the Moon’s rotation,” said Jet Propulsion Laboratory team investigator Dr. Jean Dickey. “We also have strong evidence that the Moon has a liquid core, and laser ranging has allowed us to determine with great accuracy the rate at which the Moon is gradually receding from the Earth.”

The first laser ranging retroreflector was positioned on the Moon in 1969 by the Apollo 11 astronauts. By beaming laser pulses at the reflector from Earth, scientists have been able to determine the round-trip travel time that gives the distance between the two bodies at any time to an accuracy of about 3 centimeters. The laser reflector consists of 100 fused silica half-cubes, called corner cubes, mounted in a 46-centimeter square aluminum panel. Each corner cube is 3.8 centimeters in diameter. Corner cubes reflect a beam of light directly back toward the point of origin.

“Lunar ranging involves sending a laser beam through an optical telescope,” Dickey said. “The beam enters the telescope where the eye piece would be, and the transmitted beam is expanded to become the diameter of the main mirror, then bounced off the surface toward the reflector on the Moon.”

The reflectors are too small to be seen from Earth, so even when the beam is precisely aligned in the telescope, actually hitting a lunar retroreflector array is technically challenging. At the Moon’s surface the beam is roughly four miles wide. Scientists liken the task of aiming the beam to using a rifle to hit a moving dime two miles away.

Once the laser beam hits a reflector, scientists at the ranging observatories use extremely sensitive filtering and amplification equipment to detect the return signal, which is far too weak to be seen with the human eye. Even under good atmospheric viewing conditions, only one photon is received every few seconds.

From the ranging experiments, scientists know that the average distance between the centers of the Earth and the Moon is 385,000 kilometers with an accuracy of better than one part in 10 billion. Laser ranging has also made possible a wealth of new information about the dynamics and structure of the Moon. Among many new observations, scientists now believe that the Moon may harbor a liquid core. The theory has been proposed from data on the Moon’s rate of rotation and very slight bobbing motions caused by gravitational forces from the Sun and Earth.

Ranging has also determined that the length of an Earth day has distinct small-scale variations of about one thousandth of a second over the course of a year, caused by the atmosphere, tides, and Earth’s core. In addition, precise positions of the laser ranging observatories on Earth are slowly drifting as the crustal plates on Earth drift. The observatory on Maui is seen to be drifting away from the observatory in Texas.

Data also indicate that ocean tides on Earth have a direct influence on the Moon’s orbit. Measurements show that the Moon is receding from Earth at a rate of about 3.8 centimeters per year. Ranging has also improved historic knowledge of the Moon’s orbit, enough to permit accurate analysis of solar eclipses as far back as 1400 BC. Continued improvements in range determinations and the need for monitoring the details of the Earth’s rotation will keep the lunar reflector experiments in service for years to come.

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Mayo Clinic cancer researchers have discovered a key partnership between two genes in mice that prevents the development of cancer of the lymph nodes, known as T-cell leukemia or lymphoma.

This first-time finding provides researchers with a promising target for designing new anti-cancer drugs that fight lymphomas, as well as other cancers in which this partnership exists, including breast and colon cancers.

The Mayo Clinic research report appears as the cover story in today’s edition of the journal, Cancer Cell, (http://www.cancercell.org). Jan van Deursen, Ph.D., a specialist in pediatric cancers with the Department of Pediatrics and a member of the Mayo Clinic Cancer Center, led the research team.

According to Dr. van Deursen, the Mayo Clinic cancer research team used specially-bred laboratory mice to demonstrate three things not previously known about the development of these types of cancer. They are the first to:

* Provide laboratory evidence that the gene CBP is a tumor suppressor — and that the lack of CBP contributes to the formation of lymphoma.

* Demonstrate that the absence of CBP works in partnership with low levels of a protein called p27Kip1. When these two conditions are present, lymphoma development accelerates in mice.

* Discover that two compounds — Cyclin E and Skp2 — control p27Kip1 levels.

“We not only found the tumor suppressor, we also showed what other gene defects need to occur in the same cell for cancer to progress,” says Dr. van Deursen. “Cancer is not the result of a single defect, but is related to a combination of defects and events,” he explains. “To find the best treatment, it’s vital to discover what combinations of changes have occurred with the cell to transform it from a normal cell into a cancer cell.” Lymphoma belongs to the hematologic malignancies group of cancers because it involves blood, bone marrow and lymph nodes. In general, it is one of the more common cancers and it is increasing in the United States. Each year about 50,000 Americans are diagnosed with some form of lymphoma, and another 30,000 die from the cancer.

Background Analogy: Cancer as a River and the Search for its Headwaters

Cancer researchers liken cancer to a river with directional flow. Like a river, cancer flows downstream toward production of disease. What researchers want to find is the upstream headwaters — the point of origin that eventually leads to cancer.

They look for the earliest “upstream” cellular irregularities that contribute to dangerous “downstream” conditions. In this study, Mayo Clinic researchers discovered a previously unknown early, upstream event in the cancer process — that the compounds Cyclin E and Skp2 are upstream elements that control the downstream level of p27Kip1. They found that when p27Kip1 levels are low, and when combined with the absence of CBP, conditions favor cancer.

“Low levels of p27Kip1 are often associated with human cancers and with very poor prognosis,” says Dr. van Deursen. “We have shown in our research the mechanism by which p27Kip1 gets altered. Now that we know this mechanism, we can design treatments to keep levels of p27Kip1 from going down.”

Dr. van Deursen notes that altered levels of p27Kip1 are not the result of a defective gene. Rather, the altered levels are the indirect result of high levels of the upstream molecules, Cyclin E and Skp2.

“If we can prevent these indirect upstream effects from happening, then the undesirable downstream events will not occur,” he says.

From this finding, the Mayo Clinic cancer researchers conclude that a cooperative relationship exists between the loss of CBP and depressed levels of p27Kip1 to produce cancer.

A grant to Mayo Clinic from the Department of Defense funded this research study. Researchers from St. Jude Children’s Research Hospital in Memphis, Tenn., also contributed to the investigation.

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