An Upper Cretaceous paleodrainage system on the Coastal Plain unconformity of Alabama-Georgia

ABSTRACT Rocks of the Upper Cretaceous Tuscaloosa Formation (Cenomanian) and Eutaw Formation (Santonian) in southwestern Georgia and southeastern Alabama record an interval of fluvial and nearshore marine deposition. In the vicinity of Columbus, Georgia, basal units of the Tuscaloosa Formation consist of a residual paleosol built on crystalline rocks of the Appalachian Piedmont covered by conglomeratic sandstones deposited in braided stream systems flowing across the mid-Cenomanian Coastal Plain unconformity. The unconformity, which separates Cretaceous detrital rocks from underlying metamorphic rocks and residual paleosols built on those metamorphic rocks, lies primarily within the Tuscaloosa Formation in this region and is marked at the modern surface by the geomorphic Fall Line. Mapping of the unconformity across the region reveals areas of significant paleorelief associated with a number of distinct paleovalleys incised into the mid-Cenomanian surface. The most distinct of these lie immediately east of the Alabama-Georgia state line, within 15 km of the modern Lower Chattahoochee River Valley. Spatially, these distinct paleovalleys lie immediately north of a Santonian estuarine environment recorded in the Eutaw Formation, disconformably above the Tuscaloosa Formation. Collectively, paleo-valleys in the mid-Cenomanian surface, the fluvial nature of the Tuscaloosa Formation in southwestern Georgia and southeastern Alabama, and the estuarine environment in the younger Eutaw Formation suggest a persistent (~10 m.y.) paleodrainage system that may be a forerunner to the modern Chattahoochee River.

Mechanics of side-slipping in alpine skiing. Braking and skidded traversing

A recently proposed simple approximate theory of snow machining is applied to modelling of several basic manoeuvres of alpine skiing: fall-line side-slipping, traversing, and hockey stop. The results agree with the skiing practice and explain the abnormally high friction reported in previous field studies. They also prepare foundation for future rigorous testing of the theory, which will determine its accuracy and limits of applicability.

Resilience of a Fire-Maintained Pinus palustris Woodland to Catastrophic Wind Disturbance: 10 Year Results

Increased interest in ecosystem recovery and resilience has been driven by concerns over global change-induced shifts in forest disturbance regimes. In frequent-fire forests, catastrophic wind disturbances modify vegetation-fuels-fire feedbacks, and these alterations may shift species composition and stand structure to alternative states relative to pre-disturbance conditions. We established permanent inventory plots in a catastrophically wind-disturbed and fire-maintained Pinus palustris woodland in the Alabama Fall Line Hills to examine ecosystem recovery and model the successional and developmental trajectory of the stand through age 50 years. We found that sapling height was best explained by species. Species with the greatest mean heights likely utilized different regeneration mechanisms. The simulation model projected that at age 50 years, the stand would transition to be mixedwood and dominated by Quercus species, Pinus taeda, and P. palustris. The projected successional pathway is likely a function of residual stems that survived the catastrophic wind disturbance and modification of vegetation-fuels-fire feedbacks. Although silvicultural interventions will be required for this system to exhibit pre-disturbance species composition and structure, we contend that the ecosystem was still resilient to the catastrophic disturbance because similar silvicultural treatments were required to create and maintain the P. palustris woodland prior to the disturbance event.

The Liquefaction Record of Past Earthquakes in the Central Virginia Seismic Zone, Eastern United States

Following the 2011 moment magnitude, M 5.7 Mineral, Virginia, earthquake, we conducted a search for paleoliquefaction features and found 41 sand dikes, sand sills, and soft-sediment deformation features at 24 sites exposed in cutbanks along several rivers: (1) the South Anna River, where paleoliquefaction features were found in the epicentral area of the Mineral earthquake and farther downstream to the southeast; (2) the Mattaponi and Pamunkey Rivers east of the Fall Line, where liquefiable sediments are more common than in the epicentral area; and (3) the James River and Rivanna River–Stigger Creek, where a few sand dikes were found in the 1990s. Liquefaction features are grouped into two age categories based on dating of host sediment in which they occur and weathering characteristics of the features. A younger generation of features that formed during the past 350 yr are small, few in number, and appear to be limited to the James and Pamunkey Rivers. Though there are large uncertainties in their locations and magnitudes, one or more preinstrumental earthquakes, including the 1758, 1774, and 1875 events, likely caused these features. An older generation of liquefaction features that formed between 350 and 2800 yr ago are larger, more numerous, and more broadly distributed than the younger generation of features. Several earthquakes could account for the regional distribution of paleoliquefaction features, including one event of M 6.25–6.5 near Holly Grove, or two events of M 6.0 near Mineral and M 6.25 near Ashland. Amplification of ground motions in Coastal Plain sediment might have contributed to liquefaction along the Mattaponi and Pamunkey Rivers.

Application Of The Concept And Monitoring Of Robot Line Follwer As a Prototype Of Pekanbaru Trans Metro Bus Towards The Revolution Industry 4.0 (Penerapan Konsep Dan Monitoring Robot Line Follwer Sebagai Prototipe Bus Trans Metro Pekanbaru Menuju Era Revo

Public transportation is a major part of developing an advanced and modern city. Progress in public transportation is needed to be planned and realized to deal with the development of the city together with population and economic growth. The use of the Trans Metro Pekanbaru bus transportation is not in line with the development and progress of the City of Pekanbaru, which wants to be a smart city, where the role of the Internet of Things (IoT) needs to be realized in building smart cities and currently the use of the Trans Metro Pekanbaru bus in Pekanbaru is still becoming a problem. it needs to be resolved like the Trans Metro Pekanbaru bus lane which still uses a shared lane which causes congestion and lack of good trafic regulations. Trans Metro Pekanbaru bus transportation is still weak in terms of arrival and departure times. Trans metro Pekanbaru has not yet been integrated in a system that can be monitored centrally through the application of an application system based on the Global Positioning System (GPS). To overcome this problem, it is necessary to have the Trans Metro Pekanbaru bus transportation in the form of a prototype line follower robot which is a solution to overcome this problem. The purpose of this research is to make the line follower robot as a trans-metro silmulation bus for Pekanbaru become a smart city that is able to serve and facilitate the public's need for public transportation towards the industrial revolution 4.0. Line follower robot is a robot that works by following a line in the form of a road such as a traf ic lane, where the robot works using photodiode sensors and ultrasonic sensors as proximity sensors so that it stops automatically at every stop or place where passengers rise and fall. Line follower robots are automatically controlled so programming code and fuzzy algorithms are needed. Line follower robots are also equipped with Closed Circuit Television (CCTV) to determine passenger conditions.

Dynamics of carving runs in alpine skiing. I.The basic centrifugal pendulum.

We studied perfect carving turns of alpine skiing using the simple model of an inverted pendulum which is subject to the gravity force and the force mimicking the centrifugal force emerging in the turns. Depending on the turn speed the model describes two different regimes. In the subcritical ( low speed) regime, there exist three equilibrium positions of the pendulum where the total torque applied to the pendulum vanishes -- the marginally stable vertical position and two unstable tilted positions on both sides of the vertical. The tilted equilibria correspond to the ski turns executed in perfect balance. The vertical equilibrium corresponds to gliding down the fall line without turns. In the supercritical (high speed) regime, the tilted equilibria disappear. In addition to the equilibria the model allows fall-rise solutions, where the pendulum (skier) hits (rises from) the ground, and oscillations about the vertical. These oscillations correspond to the so-called dynamic skiing where the skier never settles to a balanced position in the turn. Analysis of the available data on FIS WC races shows that elite races ski mostly in the supercritical regime. In its current form the model of centrifugal pendulum has no feedback components associated with the skier control over their runs and therefore describes a riderless mono ski. Hence the theory predicts that such a vehicle can execute carving turns automatically.

A new species of Heterotrissocladius Spärck, 1923 (Diptera: Chironomidae: Orthocladiinae) from Georgia, USA

Heterotrissocladius spiesi sp. n. is described from headwaters of two small Georgia streams, below the Fall Line in the Coastal Plain Physiologic Province, Atlantic Slope drainage. One stream is near the coast (Lower Coastal Plain) and characterized as a“blackwater” stream due to high tannin concentrations. The other stream is inland (Upper Coastal Plain), clear and not noticeably affected by tannins. The description is based on adult males, pharate male pupae and one attached larval skin. The new species is assignable to the H. marcidus species group with some exceptions. Males differ from the previous group by a reduced number of rather weak, short acrostichal setae (0-3, previously considered as typical of the subpilosus group) as well as by a very reduced wing squamal fringe compared to most members of the H. marcidus group. Males are recognizable by an elongate, thin virga, distinctive anal point and inflated/triangular gonostylus. The female is not described; the immature stages are very similar in some features to H. boltoni Sæther. At the inland stream, an adult male of the new species was found together with pharate male pupae (one with larval skin) of another, as yet undetermined species of Heterotrissocladius (marcidus group) also known from elsewhere in the state. Female adults and a pharate female pupa collected at the blackwater stream site are noted but not included in the description or type series.

Translocation of the upper soil layer in multiple operations of seedbed preparation

Translocation of tracers incorporated into the upper layer of topsoil was evaluated in the course of seedbed preparation for winter wheat. Aluminium cubes with the edge length of 16 mm were used as tracers that were placed into the soil before its tillage into furrows perpendicular to the direction of passes. After the passes of the OPALL-AGRI combined cultivator, the tracers were searched and marked using a metal detector. The translocation of tracers was evaluated during multiple passes on flatland and on the slope. During the seedbed preparation on the slope, downslope and upslope passes in a fall line direction were chosen. Results of the tracers movement measuring that simulate the soil particle translocation indicate a pronounced movement of the upper layer of topsoil during multiple downslope passes of the combined cultivator. A significant translocation was also observed after passes on flatland. A significantly smaller lengthwise translocation of tracers was found out at upslope passes. The type of translocation on flatland and upslope was quite similar, on the other hand, downslope movement was much larger. The upslope passes were found to have a very limited function with regard to the correction of the undesirable downslope movement of soil particles that occurs in the course of tillage.