Determining the depositional pattern by resistivity-seismic inversion for the aquifer system of Maira area, Pakistan.

Velocity and density measured in a well are crucial for synthetic seismic generation which is, in turn, a key to interpreting real seismic amplitude in terms of lithology, porosity and fluid content. Investigations made in the water wells usually consist of spontaneous potential, resistivity long and short normal, point resistivity and gamma ray logs. The sonic logs are not available because these are usually run in the wells drilled for hydrocarbons. To generate the synthetic seismograms, sonic and density logs are required, which are useful to precisely mark the lithology contacts and formation tops. An attempt has been made to interpret the subsurface soil of the aquifer system by means of resistivity to seismic inversion. For this purpose, resistivity logs and surface resistivity sounding were used and the resistivity logs were converted to sonic logs whereas surface resistivity sounding data transformed into seismic curves. The converted sonic logs and the surface seismic curves were then used to generate synthetic seismograms. With the utilization of these synthetic seismograms, pseudo-seismic sections have been developed. Subsurface lithologies encountered in wells exhibit different velocities and densities. The reflection patterns were marked by using amplitude standout, character and coherence. These pseudo-seismic sections were later tied to well synthetics and lithologs. In this way, a lithology section was created for the alluvial fill. The cross-section suggested that the eastern portion of the studied area mainly consisted of sandy fill and the western portion constituted clayey part. This can be attributed to the depositional environment by the Indus and the Kabul Rivers.

Diversion Colitis.

Management of the patient with diversion colitis is dependent upon both patient and disease-related factors. Patients in whom diversion is not permanent, who desire stoma closure, and who have an acceptable surgical risk should undergo re-establishment of intestinal continuity. Asymptomatic, high-risk surgical candidates need only undergo periodic, regular endoscopic surveillance of both the functional and nonfunctional large bowel according to currently accepted screening guidelines. Most symptomatic patients in whom the diversion is permanent can be treated successfully with steroid enemas, 5-aminosalicylic acid enemas or suppositories, or short-chain fatty acid enemas. If diversion is permanent, medical treatment is unsuccessful, and symptoms persist, acceptable surgical candidates should undergo resection of the excluded bowel.

Anal Carcinoma.

Carcinoma of the anus is a rare malignancy that usually is diagnosed at an advanced stage, in spite of being easily visible and accessible. Its treatment has evolved from being mainly surgical to one consisting of chemotherapy (with fluorouracil and mitomycin) and radiation (megavoltage linear accelerator therapy delivering between 40 to 50 Gy). Local surgical excision is most often performed for either carcinoma in situ or microinvasive lesions of the anal margin. Radical resection is indicated for patients with residual disease following chemoradiation or for recurrent disease.