James A. Harrell

Time-series analysis of the Pleistocene deep-sea paleoclimatic record

Abstract Pleistocene deep-sea cores V16-205, V28-239 and composite core RC11-120/E49-18 were selected for a time-series analysis of climatic periodicities which correspond to secular changes in the earths orbital parameters. These data were analyzed using the Periodic Regression with Cyclic Descent — a technique which offers three major advantages over more conventional approaches because (1) the observation interval may be unequally spaced with respect to time, (2) resolution of all the discrete periodic components present in the data, including those with low frequencies, is made possible, and (3) the associated Monte Carlo experiments permit the evaluation of the importance of the observed periodic components vis-a-vis “red” climatic noise. Analytical results indicate periodicities which correspond to secular changes in the earths orbital parameters. In particular, the results strongly suggest a quasi-periodicity of 413,000 years recorded in deep-sea globigerina oozes. Clearly this periodicity is reminiscent of a beat in the eccentricity of the earths orbit, first detected in tropical North Atlantic core V16-205 by Briskin and Berggren (1975).

Polycrystallinity: Effect on the Durability of Detrital Quartz

ABSTRACT Experimental studies using a tumbling barrel apparatus reveal the following sequence of mechanical durabilities for varieties of quartz: finely-polycrystalline quartz > coarsely-polycrystalline quartz > monocrystalline quartz. Published field studies indicate that monocrystalline quartz has a greater survival potential than polycrystalline quartz. This suggests that chemical stability is more important than inherent mechanical durability in determining the survival potential of detrital grains during their predepositional history.

Radon hazards associated with outcrops of Ohio Shale in Ohio

The indoor (basement) radon concentrations and the uranium, organic carbon, and radon contents of samples from the underlying Ohio Shale (Upper Devonian) were investigated in six approximately 100 square kilometer areas of Ashtabula, Cuyahoga, Erie-Huron, Franklin, Pike, and Logan counties. The thickness and lithology of the sediment overburden above the Ohio Shale in these areas also was investigated.Results show that the amount of radon gas emanating from the Ohio Shale is a direct function of the uranium concentration in this geologic unit and that the uranium itself is ultimately controlled by the amount of organic matter. Uranium, organic matter (as measured by total organic carbon), and radon in the Ohio Shale outcrops all increase in a westward direction across Ohio. Similarly, the indoor radon concentration in houses increases from east to west across the state.Where the average thickness of the sediment overburden exceeds 27 m (Franklin and Logan counties), much of the radon in houses may be derived from Ohio Shale clasts in the glacial till. In other areas where the average overburden thickness is 6 m or less (Ashtabula, Cuyahoga, Erie-Huron, and Pike counties), the indoor radon levels appear to be directly controlled by emanations from the underlying Ohio Shale bedrock.

Development of an indoor radon information system

Abstract This paper describes data management software for the Indoor Radon Information System (IRISDAT) that was developed in order to enable users to perform database management operations on indoor radon data for Ohio. The software is a FORTRAN-77 based program written on a VAX 6420 which can access a commercial database management utility, DATATRIEVE (Digital Equipment Corporation, Maynard, MA). The system allows for data records consisting of numerous fields and is able to perform several useful data management manipulations. The database, which can be continually updated using the system, currently consists of nearly 51,000 records of data collected from commercial, governmental and university sources. The system has been used to create collections of data and to compute statistical parameters for investigating the controls on indoor radon concentrations and for performing initial health risk assessments.

Ancient Egyptian Origins of Some Common Rock Names

Alabaster, basalt, ophiolite, porphyry and syenite are rock names that have their origins in ancient Egypt. Alabaster comes from the Greco-Roman alabastrites, a variety of travertine named for the Alabastrum region of the Nile Valley where it was quarried. Basalt is derived, through a transcription error, from the Greco-Roman basanite which is a transliteration of the pharaonic bekhen-stone, a graywacke sandstone/siltstone quarried at Wadi Hammamat in the Eastern Desert. Ophiolite and porphyry are obtained from the Roman names of two other Eastern Desert quarry stones: ophites, a gabbro from Wadi Semna, and porphyrites, an andesite/dacite porphyry from Gebel Dokhan. Syenite comes from the Roman syenites, a granite named for the Greco-Roman city of Syene at the first Nile cataract where it was quarried. Syene is a transliteration of the pharaonic Swenet and evolved into the Arabic Aswan, the modern name for the city.

The Great Pyramid Debate – Evidence from the Lauer Sample

In recent years the origin of the stone blocks used to build the 4,500 year old pyramids at Giza in Egypt has been hotly debated. The source of the controversy is the suggestion that the blocks were made from poured concrete rather than cut from natural limestone as traditionally believed. At the center of the debate is the so-called “Lauer sample,” which comes from the interior of one of the pyramids. Proponents of the concrete origin tout this specimen as a prime example of a material made from a mixture of limestone aggregate and synthetic zeolite (“geopolymer”) cement. Detailed petrographic and chemical analyses of the Lauer sample should settle the controversy. These analyses are performed in the present study, and it is concluded that this sample is a natural limestone that was quarried locally in the Eocene Mokattam Formation. There is no evidence of the special textures and zeolite cement that must exist if the sample is concrete.

Granite Platforms in the Wichita Mountains, Oklahoma: Pediment Outliers of the Southern High Plains in Texas and New Mexico

Well-developed granite platforms exist near the summits of four of the highest hills in the Lake Altus area of the western Wichita Mountains in southwest Oklahoma. These features had previously been interpreted as wave-cut benches of Permian age. New evidence indicates that they are Pliocene pediments cut at the level of the Southern High Plains, which originally extended into western Oklahoma. During the late Pliocene and early Pleistocene, this surface retreated 180 km to its present position in the Texas Panhandle.

Megascopic Classification of Rocks

A new classification of rocks that requires almost no tools other than a hand lens and that is both comprehensive and informative is described in this paper. These classifications should be useful in many classroom, laboratory, and field situations where the alternative classifications are either overly simplistic in that they provide little useful information or overly analytical in that they require optical and/or chemical data that are not readily available. The rock classifications presented here are our megascopic adaptations of the more popular analytical classifications in use today. Each of the three main rock groups is treated in two-dimensional, rectangular charts with additional appended boxes that provide optional mineralogical and textural terms that can be used with the rock names.

The roman quarry and installations in Wadi Umm Wikala and Wadi Semna

A detailed surface survey of the gabbro quarry and related facilities in Wadis Umm Wikala and Semna indicates activity in the first to second or early third centuries AD. Surface pottery found associated with quarry faces, loading ramps, related huts, skopeloi, a putative temple, a main adminstrative building and nearby hydreuma attest to intensive operations here contemporary with periods of early exploitation of the larger quarries of Mons Claudianus and Mons Porphyrites farther north in the Eastern Desert. A lengthy Greek inscription of the early first century AD recovered here over a century ago records that the ancient name of the site was Ophites.

Mapping the Tura-Masara Limestone Quarries

The Tura-Masara limestone quarries, near Cairo, supplied stone to the Old and Middle Kingdom pyramid complexes of the Memphite necropolis and also for many temples of the Middle Kingdom and later at sites throughout the Nile Valley and Delta. These underground quarries, commonly referred to as galleries, were previously known primarily from their many inscriptions. Maps with detailed plans of about 70 of the galleries were recently discovered in the British Library. These were prepared at the beginning of the Second World War for the British military in order to facilitate its occupation of the bomb-proof galleries. The maps, which also report the surface area of each gallery, not only provide much-needed cartographical documentation of one of ancient Egypt’s most important quarry complexes but also new insights into the quarrying process and use of the Tura-Masara limestone.